山药的化学成分

Studies were conducted on the chemical composition, as well as the biochemical and textural changes, occurring during storage of two cultivars of Dioscorea dumetorum yam tubers. …

The nutrient components and functional properties of Discorea alata were determined. The average crude protein of D. alata was 6.7%. Carbohydrate (81.6- 87.6%) was the predominant fraction of the tuber dry mater. The mineral contents of the yam tuber varieties were also evaluated with values ranging from 240-400mg/100g, k; 190-380mg/100g, Na; 180-340mg/100, P; 20.2-80.2mg/100g, C and 24.3-97.2mg/100g, Mg. Vitamin C content of the yam tubers ranged from 16.7-28.4mg/100g, fresh weight. Significant differences in the crude protein and mineral contents were observed among the varieties. Functional property levels in the yam tubers were found to be in the range of 0.64-0.76g/cm3 (BD); 2.90-3.65g/g (WAC); 27.0-3.5 sec (wettability) and 30-50% w/v (gelation). Significant differences in the functional properties of the yam tuber varieties were also observed. The overall results are indication of good nutritional quality and functional properties of D. alata.

… The purpose of this study was to establish the chemical compositions, enzyme activity and nutritional values of four cultivars of yam tubers at different stages of their maturation, and …

Yams (Dioscorea spp.) are widely cultivated as edible resources and medical materials in China. Characterizing chemical compositions in yam germplasm is crucial to determine their diversity and suitability for food and medicine applications. In this study, a core germplasm containing 25 yam landraces was used to create an effective classification of usage by characterizing their nutritive and medicinal compositions. All studied landraces exhibited high contents of starch from 60.7% to 80.6% dry weight (DW), protein (6.3–12.2% DW), minerals (especially Mg 326.8–544.7 mg/kg DW), and essential amino acids. Allantoin and dioscin varied considerably, with values of 0.62–1.49% DW and 0.032–0.092% DW, respectively. The quality variability of 25 yam landraces was clearly separated in light of UPGMA clustering and principal component analysis (PCA). Using an eigenvalue ≥1 as the cutoff, the first three principal components accounted for most of the total variability (62.33%). Classification was achieved based on the results of the measured parameters and principal component analysis scores. The results are of great help in determining appropriate application strategies for yam germplasm in China.

Abstract Substantial studies have been conducted on the starches derived from various yam species. These studies have examined numerous extraction methods, including acid, alkali, ammonia, water and enzymatic techniques, each yielding between 10–20% starch. The physicochemical properties of yam starches have been extensively characterized, evaluating factors, such as granule size, amylose content (ranging from 0 to 40%), gelatinization behavior and rheological profiles. Notably, the yam species D. esculenta and D. dumoterum exhibit lower amylose levels, while D. trifida can present as a waxy starch with less than 2% amylose. Minimal variation has been observed in the composition, patterning and characteristics across D. cayenensis and D. rotundata starches. Yam tubers are composed of 60–80% starch by dry matter, playing a fundamental role in the quality of yam-based foods. Yam starches have demonstrated potential as thickeners, fat replacers and edible film formers due to their physicochemical attributes, particularly their gelling properties which enhance texture and functionality. However, the industrial utilization of yam starches remains limited due to a lack of systematic data and standardized isolation methods. Further research is needed to optimize extraction protocols and expand the food applications of this versatile starch.

The chemical composition, amylose content and physio-chemical properties of dioscorea starch (Dioscorea abyssinica, Fam. Dioscoreaceae) from Ethiopia have been investigated. The proximate composition of the starch on dry weight basis was found to be 0.1% ash, 0.5% protein, 1.0% fat and 98.4% starch. The amylose content was 29.7%. Scanning electron microscopy (SEM) showed rounded granules. Particle size analysis revealed granule size distribution with a mean particle size of 29.2 μm. X-ray diffraction study showed a pattern that is typical of B-type with a distinctive maximum peak at around 17° 2 T. The moisture sorption pattern, the swelling power and the solubility values were determined and found to be lower than potato starch. Brabender viscosity curves of 6% starch paste showed a peak viscosity of 781 BU. The breakdown and retrogradation of dioscorea starch were 25 and 501 BU, respectively. DSC parameters of starch-water mixture (1:2) exhibited an onset temperature (To) of 64.2°C, a peak temperature (Tp) of 68.2°C and an endset temperature (Te) of 74.8°C. The enthalpy of gelatinization (ΔH) was 19.2 mJmg−1.

… of Dioscorea esculenta (Lour.) Burkill (kukulala, java-ala, nattala) and Dioscorea alata L. (hingurala, raja-ala) tubers grown in Sri Lanka was isolated and its morphology, composition, …

Dioscorea, consisting of over 600 species, is the most important genus in the Dioscoreaceae family; however, the practically used plants, which are commonly called yam, are restricted to a remarkably smaller number of species. Numerous studies have reported the high nutritional value of yam, particularly as an alternative source of starch and some important micronutrients. Several Dioscorea species are widely used for various medicinal purposes as well. In many studies, the bioactivities and health benefits of Dioscorea extracts and other preparations have been related to the presence of phytochemicals, which possess antioxidant properties; they are related mainly to radical-scavenging capacity in chemical assays and positive effects on the endogenous antioxidant system in cell-based and in vivo assays. Considering the increasing number of publications on this topic and the absence of comprehensive and focused review papers on antioxidant potential, this article summarizes the results of studies on the antioxidant properties of Dioscorea spp. and their relation to phytochemicals and health benefits. A comprehensive survey of the published articles has revealed that the majority of studies have been performed with plant tubers (rhizomes, roots), while reports on leaves are rather scarce. In general, leaf extracts demonstrated stronger antioxidant potential than tuber preparations. This may be related to the differences in phytochemical composition: saponins, phenanthrenes and, for some pigment-rich species (purple yams), anthocyanins are important constituents in tubers, while phenolic acids and flavonoids are characteristic phytochemicals in the leaves. The review may assist in explaining ethnopharmacological knowledge on the health benefits of Dioscorea plants and their preparations; moreover, it may foster further studies of poorly investigated species, as well as their wider application in developing new functional foods and nutraceuticals.

… character of Dioscorea species. The … Dioscorea bulbifera was 3.1 ± 0.03 g/100 g, Dioscorea deltoidea was 1.6 ± 0.06 g/100 g, Dioscorea versicolor 1.7 ± 0.02 g/100 g and Dioscorea …

… High-yielding wild species of yam (Dioscorea spp.) play a … : Dioscorea pentaphylla (five-leaf yam), Dioscorea bulbifera (bitter yam), Dioscorea hispida (intoxicating yam), and Dioscorea …

… In this study, the thermal treatment yam (Dioscorea batatas DECNE.) was analyzed for its proximate and nutritional compositions including mineral, vitamin, amino acids and fatty acids. …

… Abstract: Dioscorea yam tubers of 11 cultivars from five common species grown in Jamaica … , vitamin C, total lipids, fatty acid composition and activity of the polyphenol oxidase enzyme. …

Yams are the edible subterranean rhizomes, or tubers, of plants from the genus Dioscorea. There are approximately 600 species of yam plants in the world, with more than 90 of these growing in East Asia. One particular species, Dioscorea opposita Thunb., is highly praised as “the Chinese yam”. This distinction arises from millennia of storied history, both as a nutritional food source and as a principal ingredient in traditional Chinese medicine. Among the many cultivars of Dioscorea opposita Thunb., Huai Shanyao has been widely regarded as the best. This review surveyed the historical background, physiochemical composition, applications as food and medicine, and research prospects for the Chinese yam. Modern science is finally beginning to confirm the remarkable health benefits of this yam plant, long-known to the Chinese people. Chinese yam promises anti-diabetic, anti-oxidative, anti-inflammatory, immunomodulatory, anti-hyperlipidemic, anti-hypertensive, anti-cancer, and combination treatment applications, both as a functional food and as medicine.

Abstract In the present study, we aimed to assess the effects of hot air drying (HAD), microwave drying (MD), far-infrared radiation drying (FIRD), vacuum drying (VD) and microwave vacuum drying (MVD) on the quality, bioactive components, pasting properties, antioxidant properties, in vitro digestibility and microstructure of Chinese yam. Results showed that these drying processes greatly affected the quality of yam (p<0.05). MVD yam had a good color and its bioactive components were maintained. VD and MVD samples had the lowest setback value and breakdown value, indicating that they had a better cold paste stability and hot paste stability. In addition, MVD samples had a uniform honeycomb microscopic pore structure, and thus the rehydration rate of MVD samples was significantly higher compared with the other drying approaches. When five differently dried samples were compared by principal component analysis (PCA), the MVD samples were found to have the highest comprehensive principal component values. Therefore, based on our results, MVD was an ideal approach to dry high-quality yam.

Starchy roots and tuber crops play a pivotal role in the human diet. There are number of roots and tubers which make an extensive biodiversity even within the same geographical location. Thus, they add variety to the diet in addition to offering numerous desirable nutritional and health benefits such as antioxidative, hypoglycemic, hypocholesterolemic, antimicrobial, and immunomodulatory activities. A number of bioactive constituents such as phenolic compounds, saponins, bioactive proteins, glycoalkaloids, and phytic acids are responsible for the observed effects. Many starchy tuber crops, except the common potatoes, sweet potatoes, and cassava, are not yet fully explored for their nutritional and health benefits. In Asian countries, some edible tubers are also used as traditional medicinal. A variety of foods can be prepared using tubers and they may also be used in industrial applications. Processing may affect the bioactivities of constituent compounds. Tubers have an immense potential as functional foods and nutraceutical ingredients to be explored in disease risk reduction and wellness.

… This study aimed to investigate the phytochemical composition of Chinese yam aqueous extract (CYW) and evaluate its gastroprotective effects against ethanol-induced gastric injury in …

… Dioscorea polystachya, commonly known as Chinese yam, was domesticated in China … the bioactivities of yam while discussing the therapeutic potential of its key phytochemicals. …

Abstract China is an important domestication center of yams, and two main yam species of Dioscorea opposita and D. alata are commonly cultivated in China. However, the differences of nutritional and medicinal characteristics between the two species and their subgroups remain unclear, which would greatly affect the resource conservation and commercial utilization of yams. In this study, typical yam resources including the species of D. opposita (wild and cultivated Ruichang yam from southern China, and Tiegun yam from northern China) and two landraces of D. alata (Longyan yam and Anyuan yam from southern China) were selected as materials. Nutritional traits and medicinal characteristics were determined and analyzed respectively. The results showed that there was no significant differences in the content of most nutrients between D. opposita and D. alata, but most cultivated Ruichang yam of D. opposita showed higher levels of starch, soluble sugar, sucrose, and ascorbate in tuber than that in yam from D. alata. Moreover, an UPLC-MS method was developed for identification and determination of medicinal characteristics in the two species. The results showed that allantoin can be detected in all selected samples. Cultivated Ruichang yam of D. opposita possessed the highest allantoin content among the tested materials, and was significantly different with that in Tiegun yam and D. alata. Dioscin was not detected in D. alata. Overall, there was little difference in nutritional composition between D. opposita and D. alata, but the medicinal quality of D. opposita was better than that of D. alata. Due to the outstanding comprehensive quality, the local variety of cultivated Ruichang yam can be further developed and utilized.

… Chinese yam, a group of vegetables belonging to the species Dioscorea opposita, has a … diverse components found in yam (Dioscorea spp.), including yam polysaccharides, dioscin, …

… Chinese yam (CY), derived from the root of Dioscorea … We identified 71 phytochemicals in CY and 40 UA-related target … led to the selection of five phytochemical-XDH complexes for …

… than Chinese yam flesh (CYF), whereas the bioactivity of yam … the antitumor effect of Chinese yam flesh and peel in tumor-… Phytochemical investigations of D. opposite have revealed …

The quest for a food secure and safe world has led to continuous effort toward improvements of global food and health systems. While the developed countries seem to have these systems stabilized, some parts of the world still face enormous challenges. Yam (Dioscorea species) is an orphan crop, widely distributed globally; and has contributed enormously to food security especially in sub-Saharan Africa because of its role in providing nutritional benefits and income. Additionally, yam has non-nutritional components called bioactive compounds, which offer numerous health benefits ranging from prevention to treatment of degenerative diseases. Pharmaceutical application of diosgenin and dioscorin, among other compounds isolated from yam, has shown more prospects recently. Despite the benefits embedded in yam, reports on the nutritional and therapeutic potentials of yam have been fragmented and the diversity within the genus has led to much confusion. An overview of the nutritional and health importance of yam will harness the crop to meet its potential towards combating hunger and malnutrition, while improving global health. This review makes a conscious attempt to provide an overview regarding the nutritional, bioactive compositions and therapeutic potentials of yam diversity. Insights on how to increase its utilization for a greater impact are elucidated.

… This study investigated the effect of diosgenin, a yam-derived phytochemical, on the growth of enteric lactic acid bacteria (LAB). The in vivo effect of diosgenin on the density of intestinal …

Graphical abstract

… China. Significant differences in allantoin contents were observed between interspecific and intraspecific yam … of Chinese yams and a reference for breeding high-quality yam varieties. …

… The fleshy underground stem of Dioscorea alata (Rajala and Hingurala) contains only a single large tuber per vine. Dioscorea are seasonal crops and generally planted in the end of …

… 5) are the major active constituent components of D. bulbifera. The most active constituents of tubers of D. bulbifera have been reported as flavonoids, which account for 39.6% (…

… The objective of this study was to evaluate and compare the nutritional and antinutritional profiles of the two tuber forms. The proximate and phytochemical constituents were determined …

This review will summarize some of the important reports on the chemistry and the biological activities of Dioscorea steroid saponins from the literature data of recent years (2000–2006) …

Abstract The tubers of Dioscorea persimilis have been widely consumed as a food and for the treatment of sonasthenia, intestinal disease, diarrhea, long-term dysentery, spermatorrhea, metritis, kidney failure, back pain, dizziness, and night sweats. The present study describes the isolation of 11 secondary metabolites, including three new phenanthrenes namely diospersimilosides A (1) and B (2) and diosbiphenanthrene (3), and eight known phenolic compounds: 2,4,6,7-tetrahydroxy-9,10-dihydrophenanthrene (4), aerosin (5), gastrodin (6), 2-phenylethyl-β- d -glucopyranoside (7), afzelechin (8), catechin (9), eucomic acid (10), and vanillic acid-4-O-β- d -glucopyranoside (11) from the tubers of D. persimilis. Their chemical structures were elucidated based on comprehensive analyses of the NMR and mass spectra. Evaluation of their cytotoxicity against three human cancer cell lines, including liver (HepG2), breast (MCF7), and melanoma (SK-Mel-2) revealed that the phenanthrene metabolites (3-5) possess cytotoxicity toward all the cell lines, with IC50 values ranging from 8.2–68.4 μM. Our results revealed that the free of the hydroxy groups plays an important role in cytotoxicity of the phenanthrenes and suggests that pohydroxylated dihydrophenanthrene and biphenanthrene metabolites could be considered as promising cytotoxic agents against human cancer cells.

The antibacterial activities and bioactive constituents of ethanolic and aqueous extract of parts of the tuber against ten (10) clinical pathogens were determined, using agar well diffusion and standard techniques respectively. The proximate profile of this tuber included moisture content, ash, crude protein, fat, fibre and carbohydrate with varying percentages. The tuber was recorded to contain higher amount of saponin with the average of 24 mg/g, followed by cardiac glycosides with 13.13 mg/g, terpenoid with 8.48 mg/g, flavonoids followed with 5.36 mg/g and tannin with 4.21 mg/g was the least among the bioactive ingredients. Except for Proteus vulgaris, Serratia liquefaciens, Micrococcus luteus, Bacillus cereus and Citrobacter freundii, other test isolates were susceptible to the effect of the ethanolic extract of the peel of D. bulbifera at 500 µg/ml. High inhibition zones (between 17 and 22 mm) were recorded against 80% of the test organisms at 1000 µg/ml, except for 15 mm zone recorded against Bacillus cereus. The MIC and MBC of extract of D. bulbifera ranged in respect to the parts from 125 µg/ml to 500 µg/ml; and 250 µg/ml to 1000 µg/ml for peels and bulbils respectively. Antibacterial activity of the ethanolic and aqueous extracts of the bulbils of D. bulbifera was however, not profound in this present study compared to that of the peel. This study therefore, affirmed that D. bulbifera is a novel source of bioactive compounds which do not only enhance the antibacterial properties, but also ascertain its health promoting qualities.

Abstract Eight yam species (Dioscorea spp.) represented by 522 accessions (landraces and hybrids) were analysed for the individual sugars, catechins, phenolic acids and saponins contents of their tuber flours. Maltose, sucrose, glucose and fructose were quantified. Reducing sugars mean values were highly variable within species and ranged from 0.16%dry weight (DW) (SD ± 0.12) in D. dumetorum to 3.15%DW (±2.49) in D. esculenta. Maltose was detected only in D. esculenta. Chlorogenic acid, gallic acid and other phenolic acids ranged from 4.33 mg/g DW in D. bulbifera to 4.87 mg/g in D. alata and 9.55 mg/g in D. nummularia but were not detected in other species. Catechins (epicatechin and catechin) were highest in D. bulbifera bulbils (25.18 mg/g) and tubers (6.96 mg/g), and lowest in D. esculenta (0.32 mg/g). Their content is significantly correlated with dark flour colour and they most likely contribute to the oxidation of tuber flesh. Saponins (dioscin and gracillin) were quantified in only two species: D. cayenensis (5.94 mg/g, SD ± 3.78) and D. esculenta (3.74 mg/g, SD ± 3.72). Varietal selection may tend to reduce sugars levels and increase secondary metabolites with bioactive properties. HP-TLC is a suitable technique for the rapid quantification of compounds related to yam tuber flour quality.

Yam is a versatile economic crop that serves both medicinal and dietary purposes. Dehua County, located in Fujian Province, China, is renowned as one of the major yam production areas, with a cultivation history spanning over 600 years. It has successfully cultivated Qingfeng yam and Ziyu yam, both of which have been recognized with China’s “Geographical Indications for Agricultural Products.” However, no comprehensive studies have been conducted to evaluate their quality. This study meticulously utilized the authentic medicinal material “Iron yam” as a benchmark, employing advanced techniques such as high-performance liquid chromatography (HPLC), ultraviolet spectrophotometry, and flame atomic absorption spectrometry to systematically analyze the nutritional and hypoglycemic active components of three distinct yam varieties. In order to interpret the data, descriptive statistics, correlation analysis, principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), cluster analysis and multiple linear regression analysis were systematically applied. The results revealed significant variations in the concentrations of various indicators across the three yam types. Correlation analysis identified 65 pairs of indicators with exceptionally strong correlations and 39 pairs with statistically significant associations. Additionally, the principal component analysis demonstrated that Iron yam exhibited the most favorable overall quality. Notably, Ziyu yam, characterized by its high concentration of hypoglycemic active compounds, emerged as a promising raw material for the production of hypoglycemic products, showcasing significant potential in this field.

… , sapogenins, saponins, starch, mucopolysaccharides, proteins, … polysaccharides and total flavonoids were higher in the Henan yams than in the Guangdong, Guizhou, and Hubei yams. …

Yam is used as common herbal remedy in traditional Chinese medicine and is grown all over Asia. According to previous research, one of the primary bioactive components of yam is yam polysaccharide. To shed light on the mechanism of yam polysaccharide in ulcerative colitis (UC), a yam heteropolysaccharide named CYP-3a was isolated and purified using ultrasonic extraction, the trichloroacetic acid technique, DEAE cellulose-52 and a Sephadex G75 column. CYP-3a comprises rhamnus: arabinose:galactose:mannose:galacturonic acid glucuronic acid, with a molar ratio of 2.25:4.17:3.30:0.09:0.13:0.26. CCK-8 and ELISA analysis results showed that CYP-3a increased the number of dextran sodium sulphate (DSS)-induced Caco-2 cells and could reduce and inhibit their inflammatory response by lowering the amounts of secreted TNF-α and IL-6. Western blot data demonstrated that CYP-3a at various doses could suppress the endoplasmic reticulum stress-mediated apoptotic pathway generated by DSS-induced UC and down-regulate the protein levels of GRP78, CHOP and NF-κB.

Korean yams are abundant in bioactive compounds with significant health-promoting properties. This study evaluated the anti-inflammatory potential of ethanol and water extracts from Dioscorea polystachya and Dioscorea bulbifera in RAW 264.7 macrophage cells. Among the extracts, the 95% ethanol extract exhibited the most potent inhibition of reactive oxygen species (ROS) and nitric oxide (NO) production, warranting further exploration of its mechanisms of action. Further analysis revealed that the ethanol extract modulated key inflammatory signaling pathways, including MAPK and NF-κB, contributing to its anti-inflammatory activity. Additionally, mucilage polysaccharides, a key bioactive component of Korean yams, were extracted and characterized for their structural and functional properties. These polysaccharides demonstrated immune-enhancing effects by reducing ROS and NO production while increasing phagocytic activity in the RAW 264.7 cells. Their prebiotic potential was also assessed through microbial growth assays, which showed an enhanced proliferation of beneficial bacteria such as Lactobacillus and Bifidobacterium. Furthermore, the adhesion assays using Caco-2 intestinal epithelial cells revealed that these polysaccharides promoted probiotic adhesion while inhibiting the adhesion of pathogenic bacteria. These findings highlight the bioactive potential of ethanol extracts and mucilage polysaccharides from Korean yams, emphasizing their promising applications as anti-inflammatory, immune-modulating, and prebiotic agents for functional food and nutraceutical development.

Yam (Dioscorea spp.), known as an edible and medicinal tuber crop in China, has been used historically for the treatment of diabetes, diarrhea, asthma, and other ailments in traditional Chinese medicine. Moreover, it has been consumed as starchy food for thousands of years in China. Modern phytochemistry and pharmacological experiments have been proved that non-starch polysaccharide is one of the main bioactive substances of yam. Many studies have been focused on the isolation and identification of polysaccharides and their bioactivities of Chinese yam. However, due to the difference in the variety of raw materials and the method of polysaccharides extracting, the structure and biological activity of the obtained polysaccharides also differ. It has been demonstrated that Chinese yam polysaccharide has various important biological activities, such as hypoglycemia, immunomodulatory, antioxidant, and antitumor activities. This paper is aimed at summarizing previous and current references of the isolation processes, structural features and bioactivities of yam polysaccharides. The review will serve as a useful reference material for further investigation and application of yam polysaccharides in functional foods and medicine fields.

… , polysaccharides, fatty acids, carbohydrates, trace minerals, proteins and beta-carotene in the Chinese yam. … The polysaccharides and beta carotene components also help restore the …

… There are abundant water-soluble polysaccharides in … [28] water -soluble polysaccharide extracted from yam tuber (D. … The use of plant extracts like saponin and flavonoids are better …

… Based on these findings, we suggest that water-soluble mucilaginous polysaccharides … rich in phytochemicals including phenolics, saponins, polysaccharides, and mucilages. Based on …

… were selected to extract saponins from purple yam root and the … highest extraction yield for saponins. The optimal extraction … The extraction rate (ER) of purple yam saponins was 0.935%…

Yam as a medicinal and edible resource plant, is abundant in bioactive compounds including polysaccharides, polyphenols, allantoin, and saponins, these constituents endow yam with diverse functional properties, such as antioxidant, anti-diabetic, anti-tumor, immunomodulatory and alleviating enteritis effects. The extraction methods, functional properties, and the primary mechanisms through which these compounds exert their effects in different varieties of yams from various regions are reviewed, and the future research priorities are proposed to offer valuable insights for the advanced processing of yams and to inform further investigations into their functional characteristics.

Foshou yam (Dioscorea opposita Thunb.), cultivated as a vegetable in the region of eastern Hubei Province, China, is a nutritious delicacy. Polysaccharides in the genus Dioscorea play important roles in health-promoting activities. Previous extraction methods used to obtain polysaccharides from Foshou yam (FYP) included water and enzymes, but not alkali conditions. The extraction methods greatly influenced the structure and biological properties of polysaccharides. Hence, in the present work, the alkali extraction of FYP was explored and optimised using the response surface method. The characterisation and antioxidant activity of FYP were also investigated. The results showed that the optimal extraction conditions were as follows: sodium hydroxide concentration, 1.0 mol/L; extraction time, 8 h; and solvent-to-material ratio, 10 mL/g. Under these conditions, the FYP extraction yield was 64.52 ± 0.23%. FYP contained 91.70% of the total sugar with a minimal amount of protein. FT-IR analysis revealed the presence of α-D-glucopyranose in FYP. Congo Red tests indicated that the triple helical conformation in FYP did not exist. In addition, in vitro antioxidant activity experiments revealed that FYP exhibited good scavenging capacity on DPPH and superoxide anion free radicals. These results indicated that the FYP can be used as a novel natural antioxidant in the functional food industries.

… yam tubers possessing bioactivities include saponin derivatives such as diosgenin and dioscin, flavonoids… Studies have shown that yam polysaccharides possess various biological …

… Allantoin was well preserved across all thermally processed yam flours. Saponins and … Steaming-refrigeration and extrusion-refrigeration effectively modulate starch digestibility of yam …

Abstract The air yam (Dioscorea bulbifera) is an unconventional vegetable that produces a reserve stem, which has polysaccharides in its composition. These biopolymers, in turn, have aroused industrial interest due to many of their properties and applications in several areas, such as agro-food, chemical, pharmaceutical, textile, metallurgical, oil, among others. The objective of this work is to characterize the polysaccharide present in the raw and pre-purified air yams, as well as to verify its potential antioxidant capacity. The FTIR analysis showed in the two samples, a characteristic OH band at approximately 3250 cm−1, which is characteristic of polysaccharides. Through the SEM it was possible to analyze the morphology of the samples and verify that they are composed of films or “sheets” without measurable format. Furthermore, by XRD the samples were found to be an amorphous material, with peaks of crystallinity being observed at approximately 21.54° and 23.62° 2θ. Thermal analysis indicates that the NDP sample presents three regions of mass loss, the first one running up to 100 °C and may be associated with water loss; the second occurs from 150 °C, and occurs in several steps that can be visualized by DTG, and the third from 550 °C. The organic matter present in the sample was about 84%. The DP (Dialysed Polysaccharide) sample, in turn, also presented three regions of mass loss, the first one occurring up to 150 °C, the second from 175 °C and the third, from 425 °C. All these mass losses occur in only one stage. The organic matter present in the sample was approximately 80%. The samples presented potential antioxidant activity when analyzed by DPPH, ABTS, FRAP, OH radical removal, H2O2 removal and reducing power. The obtained results are very important, as they reveal information about the chemical characteristics and potential bioactivity of the dialysed and non-dialysed polysaccharide of D. bulbifera.

The rhizoma of Dioscorea hemsleyi (DH) has been used as a treatment of diabetes in China for hundreds of years. Polysaccharides in DH were extracted by using ultrasonic-assisted …

The edible tubers from different species of Dioscorea are a major source of food and nutrition for millions of people. Some of the species are medicinally important but others are toxic. The genus consists of about 630 species of almost wholly dioecious plants, many of them poorly characterized. The taxonomy of Dioscorea is confusing and identification of the species is generally problematic. There are no adequate anatomical studies available for most of the species. This study is aimed to fill this gap and provides a detailed investigation of the anatomy and micro-morphology of the rhizomes and tubers of five different species of Dioscorea, namely D. balcanica, D. bulbifera, D. polystachya, D. rotundata and D. villosa. The primary features that can help in distinguishing the species include the nature of periderm, presence or absence of pericyclic sclereids, lignification in the phloem, types of calcium oxalate crystals and features of starch grains. The descriptions are supported with images of bright-field and scanning electron microscopy for better understanding of these species. The diagnostic key of anatomical features included in this paper can help distinguish the investigated species unambiguously. Additionally, HPTLC analyses of authentic and commercial samples of the five species are described.

The purpose of this study was to investigate the influence of particle size on  the  chemical properties  of yam flour  in five  cultivars, yellow/YY, orange/OY, light purple/LPY, purple/PY, and dark purple/DPY. With a mesh sieve, three  flour fractions  were separated according to particle size:  small (128.6-139.7 µm), medium (228.7-257.9 µm), and large (475.4-596.3 µm). The content of moisture (6.81-11.26 %db) and lipids (4.48-9.85 %db) decreased with the increase of particle size, while proteins (4.48-9.85 %db) and carbohydrates (78.12-83.76 %db) were not influenced by particle size. Folin-Ciocalteu reagent and chlorogenic acid were used as standard to investigate the total phenolic compounds  in  the  yam  flour,  and  high-performance liquid chromatography (HPLC) was used to investigate the anthocyanin and carotene contents. It was found that there was no size influence on the content of phenolics (0.27-2.82%db), anthocyanin (2.25-15.27  mg/100g db) in LPY, PY, DPY  or  carotene (23.75-132.12 mg/100g db) in YY, OY. The differences in chemical composition were due to differences in particle size and heat treatment, but may also have been caused by the different composition of the milling process.

… time from yam tubers (Dioscorea pseudojaponica Yamamoto) from Taiwan… Their structures were characterized as 26-O-β-d-… The methanol extract of yam tubers was fractionated by XAD-…

Ethnopharmacological relevance: Yam (Dioscorea sp.) extracts have been shown to possess a vast array of medicinal properties such as antihypocholesterolemic, antiatherogenic and antihypertensive bioactivity. However, the compounds conferring its antihypertensive bioactivity have not been fully explored. Aim of the study: The objective of this study was to identify extractable bioactive fractions and associated compounds in Jamaican Renta Yam (Dioscorea alata) that contributes to its antihypertensive properties, using an activity driven chemoinformatic profiling method. Materials and methods: A diethyl ether extract (DR2) of Dioscorea alata was obtained by sequential Solid-Liquid extraction (SLE) coupled to SPE-HPLC fractionation and its chemical composition was analyzed by GC-MS analysis. Its influence on hypertension was evaluated through a combination in vivo and in vitro ACE-Inhibitory activity assays and by molecular docking of the identified compounds to the ACE enzyme. Results: SLE revealed the presence of potent antihypertensive activity (ACE IC50 41.99 μg/mL) in the diethyl ether extract (DR2). GC-MS analysis of DR2 indicated the presence of small organic compounds (95.1 g/mol to 200 g/mol) with 2-Phenyl-1,3-oxazol-2-ine (2PO) being the most predominant small organic compound present in the bioactive extract. The binding affinity of 2PO was assessed using molecular docking of 2PO to the ACE enzyme and showed strong binding affinities forming two (2) hydrogen bonds with Tyr135 and Trp220 in the active site of the enzyme. The in vivo effect of DR2 using human umbilical vein endothelial cell lines (HUVECs) revealed; a significant dose-dependent ACE-Inhibitory activity, a stimulating of Nitric Oxide (NO) release and no toxicity towards HUVECs. Conclusion: Overall, this study identified Jamaican Renta Yam (Dioscorea alata) as an alternative source of antihypertensive compounds which may address the toxicity seen with known synthetic antihypertensives agents.

… MS n ) method was developed for the analyses and characterization of steroidal saponins in plant extract from the rhizome of Dioscorea nipponica Makino. The HPLC experiments were …

Abstract An alkali-extracted polysaccharide (HY-B) was isolated and purified from Dioscorea opposita Thunb. (Huai Yam). Its chemical structure was analyzed with FT-IR, GC-MS and 1 D, 2 D-NMR spectrometry. It was proved that HY-B is mainly composed of α-1,4-linked glucose, which is similar to starch, but the starch-iodine color test proved that it was not starch. The chain conformation of HY-B was analyzed by SEC-MALLS-RI and TEM, indicated that HY-B exists in a random coil conformation. Its molecular weight is 18.7 kDa, and the molecular size is about 100 nm. MTT assays indicated that HY-B was nontoxic to RAW 264.7 cells in vitro. The results of anti-inflammatory studies showed that HY-B could inhibit the production of NO and TNF-α in RAW 264.7 macrophage stimulated by lipopolysaccharides (LPSs). This work provided the important information about the anti-inflammatory active component of Huai Yam and its potential applications in the food and health industries. Graphical Abstract

Gadung (Dioscorea hispida Dennst) tuber contains dioscorin, an alkaloid with high angiotensin converting enzyme-inhibitory cap acity. In this research, dioscorin was extracted using microwave assisted extraction (MAE). The objectives of this research w ere to investigate the influence of ethanol concentration (75 % to 96 % w/w), solvent-material ratio (10 : 1 to 20 : 1) and m icrowave power (100 W to 400 W) on the extraction yield, and to develop a mathematic model to represent that process. The opt imum condition for this process was extraction using 85 % aqueous ethanol at solvent-material ratio of 12.5 : 1, and m icrowave power of 100 W for 20 min. The mathematic model agreed well with the experim ental data with average error of 2.96 %.

ABSTRACT The nutritional value and medicinal properties of highly edible Bulbils of Dioscorea bulbifera L are still unexplored. This study reported the nutritional and medicinal values by In vitro, and In silico studies along with chemical profiling using LC-MS. The proximate analysis was conducted by the AOAC method. The antioxidant and antidiabetic activities were assessed using DPPH and α- α-glucosidase enzyme inhibition assay. Molecular docking was used to do an In silico examination of the identified molecules, and ADMET analysis of the hit candidate was also performed. The result showed that bulbils of D. bulbifera were found to have a higher percentage of protein (8.83%), fat (0.96%), and fiber (5.40%). It exhibited significant levels of phenolic and flavonoid content 106.93 ± 0.02 mg GAE/g and 11.51 ± 0.02 mg QE/g, respectively. The ethyl acetate fraction of D. bulbifera showed potent antioxidants with an IC 50 = 13.75 ± 0.6 μg/mL. Furthermore, the methanol extract showed more than 50 % inhibition activity with IC 50 values of 26.29 ± 0.6 μg/mL and 191.2 ± 0.7 μg/mL against α-glucosidase and α-amylase, respectively. The ethyl acetate fraction showed higher α-glucosidase and α-amylase inhibitory activity with an IC 50 of 14.42 ± 0.4 μg/mL and 171.5 ± 0.4 μg/mL, respectively, compared to the standard acarbose (p < 0.05). Chemical profiling of most bio-active ethyl acetate fraction was done using LC-MS analysis, where eleven compounds were annotated. In conclusion, bulbils of D. bulbifera demonstrate promising anti-diabetic activity through In vitro and In silico studies.      

… production of diosgenin with genetic and phytochemical fidelity assessments. Murashige and … A phytochemical analysis by liquid chromatography-mass spectrometry (LC-MS) showed …

INTRODUCTION Dioscorea septemloba Thunb. (DST), the rhizome of Dioscorea spongiosa J. Q. Xi, M. Mizuno et W. L. Zhao or Fuzhou Dioscorea futschauensis Uline ex R. Kunth, has multiple biological activities. OBJECTIVES We aimed to comprehensively characterize the chemical composition of DST and develop a quality control method. METHODS Based on a UHPLC/Q-Orbitrap-MS platform, we developed an offline 2D LC-MS method (HILIC×RPLC) to characterize the chemical constituents in the 75% ethanol extract of DST at first. Secondly, a data-independent acquisition mode (DIA) was further established to conduct rapid qualitative analysis of compounds in DST from different habitats. Then, six differential compounds were screened out and selected as quantitative markers by UPLC-QQQ-MS to evaluate the content of DST from different habitats. RESULTS In total, 137 compounds were identified in DST by combining offline 2D LC-MS with LC-DIA-MS/MS. Then, simultaneous targeted/non-targeted scanning technology was established based on the precursor ion list. Finally, six compounds, including dioscin, gracillin, pseduoprotodioscin, pseudoprotogracillin, protodioscin, and protogracillin, were accurately determined. The method validation showed a good linear relationship in the concentration range investigated (R2 > 0.999). The average recovery ranged from 86% to 107.5%, and LOD and LOQ were between 0.01 and 0.40 μg·mL-1 . CONCLUSION Our strategy integrating offline 2D LC-MS and the DIA mode could effectively separate and identify compounds from DST, indicating it can be used in subsequent compounds characterization studies. At the same time, the quality of DST was comprehensively and systematically evaluated.

Yams (Dioscorea spp.) are a multispecies crop with production in over 50 countries generating ~50 MT of edible tubers annually. The long-term storage potential of these tubers is vital for food security in developing countries. Furthermore, many species are important sources of pharmaceutical precursors. Despite these attributes as staple food crops and sources of high-value chemicals, Dioscorea spp. remain largely neglected in comparison to other staple tuber crops of tropical agricultural systems such as cassava (Manihot esculenta) and sweet potato (Ipomoea batatas). To date, studies have focussed on the tubers or rhizomes of Dioscorea, neglecting the foliage as waste. In the present study metabolite profiling procedures, using GC-MS approaches, have been established to assess biochemical diversity across species. The robustness of the procedures was shown using material from the phylogenetic clades. The resultant data allowed separation of the genotypes into clades, species and morphological traits with a putative geographical origin. Additionally, we show the potential of foliage material as a renewable source of high-value compounds.

Yams (Dioscorea spp.) are cultivated and consumed as edible tubers, while their leaves are discarded as waste or burned with negative environmental impact. Herein, the metabolites of two yam species (Danma, DAN; Dunggeunma, DUN), harvested in June, July, and August, were profiled using GC-TOF-MS and UHPLC-LTQ-Orbitrap-MS/MS and the antioxidant activity of the extracts was evaluated to stimulate the utilization of yam leaves as a by-product. We observed that the relative levels of amino acids, organic acids, sugars, and saponins decreased linearly with prolonged harvest time, while fatty acid, phenanthrene, and flavonoid levels gradually increased. Furthermore, the leaf extracts obtained in August exhibited the highest antioxidant activity. To determine the antioxidant-contributing metabolites, OPLS-DA was performed for the leaf metabolites of DAN and DUN leaves harvested in August. Hydroxytyrosol-glucoside, apigenin-rhamnoside, and rutin were more abundant in DUN, while luteolin, phenanthrene derivatives, epicatechin, and kaempferide were relatively higher in DAN and their respective metabolites were positively correlated with the antioxidant activity. Moreover, secondary metabolites were more abundant in the leaves than in the roots, and consequently, the antioxidant activity of the former was also higher. Overall, the potential value of yam leaves as a renewable source of bioactive compounds is proposed.

Ninety-seven percent of yam (Dioscorea spp.) production takes place in low income food deficit countries (LIFDCs) and the crop provides 200 calories a day to approximately 300 million people. Therefore, yams are vital for food security. Yams have high-yield potential and high market value potential yet current breeding of yam is hindered by a lack of genomic information and genetic resources. New tools are needed to modernise breeding strategies and unlock the potential of yam to improve livelihood in LIFDCs. Metabolomic screening has been undertaken on a diverse panel of Dioscorea accessions to assess the utility of the approach for advancing breeding strategies in this understudied crop. Polar and lipophilic extracts from tubers of accessions from the global yam breeding program have been comprehensively profiled via gas chromatography-mass spectrometry. A visual pathway representation of the measured yam tuber metabolome has been delivered as a resource for biochemical evaluation of yam germplasm. Over 200 compounds were routinely measured in tubers, providing a major advance for the chemo-typing of this crop. Core biochemical redundancy concealed trends that were only elucidated following detailed mining of global metabolomics data. Combined analysis on leaf and tuber material identified a subset of metabolites which allow accurate species classification and highlighted the potential of predicting tuber composition from leaf profiles. Metabolic variation was accession-specific and often localised to compound classes, which will aid trait-targeting for metabolite markers. Metabolomics provides a standalone platform with potential to deliver near-future crop gains for yam. The approach compliments the genetic advancements currently underway and integration with other ‘–omics’ studies will deliver a significant advancement to yam breeding strategies.

The genus Dioscorea is traditional Chinese medicine producing a variety of pharmacological active substances especially saponins. In our study, the secondary metabolism of Dioscorea zingiberensis and D. opposita that have significantly different saponin contents were investigated. The saponin content was significantly different between two species. KEGG pathway enrichment analysis of transcriptomic data revealed significant differences between the two species in several metabolic pathways, including secondary metabolite biosynthesis, phenylpropanoid biosynthesis, starch and sucrose metabolism, photosynthesis, flavonoid biosynthesis, and steroid biosynthesis. Notably, 28 differentially expressed genes (DEGs) were linked to steroid biosynthesis. Through further metabolome analysis, we detected a total of 1 010 metabolites, and 212 (52 upregulated and 160 downregulated) differential metabolites (DAMs) were screened. The DAMs were mainly enriched in biosynthesis of secondary metabolites (32), amino acids (17), carbon metabolism (10), pentose phosphate (7), phenylalanine metabolism (6), and steroid (2). The combined analysis of transcriptome and metabolome found that terpenoid backbone biosynthesis, flavonoid biosynthesis and steroid biosynthesis were significantly enriched. In addition, we screened three candidate glycosyltransferase genes involved in dioscin biosynthesis. The integration of transcriptome and metabolome analyses revealed a strong correlation between metabolite contents and gene expression. Three genes, J5N97_024139 (sterol 3-beta-glucosyltransferase 1, UGT80A2), J5N97_022450 (sterol 3-beta-glucosyltransferase 2, UGT80B1) and J5N97_004795 (UDP-rhamnose transporter 1, URT1), were significantly positively correlated with dioscin biosynthesis. These results provide valuable data for the study of secondary metabolites, particularly saponins, and lay a solid foundation for breeding ideal Dioscorea plants.

Studies have revealed that Dioscorea hispida tubers contain a poisonous substance called alkaloid dioscorine. The method for removing alkaloid dioscorine in Dioscorea hispida is explored in this research through a soaking process. The tubers were peeled, washed, sliced, and soaked for 5 days in either 1.0 M sodium chloride (NaCl) or distilled water. The aim of this study was to firstly identify the amount of toxic dioscorine remaining after soaking for 5 days, and then determine the best solution for removing dioscorine compounds in the tubers that were obtained from a tropical area in Peninsular Malaysia. The liquid chromatography electrospray ionization mass spectrometric (LC-ESI-MS) systems were used to identify the presence of alkaloid dioscorine compounds within Dioscorea hispida tubers. The analysis showed that no dioscorine compounds were present in day 5 for samples soaked in the NaCl solution. However, the relative abundance in the distilled water solution at day 5 was 281000, indicating a 95% decrease of the relative abundance value of the dioscorine compounds. This work aimed to determine the minimum days needed to remove the poisonous element before Dioscorea hispida tubers could be used for food consumption or for any other applications.

The rhizome of Dioscorea bulbifera (RDB) has been used in folk and traditional Chinese medicine for the treatment of thyroid diseases and cancer. However, the chemical constituents are not fully clear. In this study, high-performance liquid chromatography coupled to electrospray ionization and quadrupole time-of-flight mass spectrometry was successfully used for the comprehensive characterization of chemical constituents in RDB. As a result, a total of 40 compounds were identified in RDB by comparison with the authentic standards or reported references, including 13 flavonoids, 2 diterpenoids, 2 stilbenoids, 12 steroidal saponins, and 11 phenolic derivatives. This study comprehensively elucidated the chemical basis of RDB and provided a robust foundation for the quality control and pharmacology research in the future.

Dioscorea caucasica Lipsky is a tertiary relict endemic plant naturally growing in the western part of the trans-Caucasus regions; it has adapted and successfully grows in the temperate region of the Baltic countries. Information about its phytochemical composition and bioactivities is rather scarce. This study reports the results of the identification of 41 compounds in D. caucasica leaf and tuber hydroethanolic extracts using UPLC-QTOF/MS. Organic acids were found in both extracts; hydroxycinnamates and flavonoids were the main phytochemicals in the leaves, while steroidal glycosides, fatty acids (mainly hydroxylated) and carbohydrates were found in the tubers. Leaf extracts inhibited enzymes in a dose-dependent manner and were remarkably stronger inhibitors of physiologically important enzymes, namely α-amylase (48.6% at 480 µg/mL), α-glucosidase (IC50 = 41.99 and 47.95 µg/mL with and without 0.1 M Na2CO3), acetylcholinesterase (45.85% at 100 µg/mL) and angiotensin-converting enzyme (IC50 = 829.7 µg/mL), most likely due to the presence of some quantified polyphenolic antioxidants. The mode of inhibition of α-glucosidase and acetylcholinesterase was assessed via kinetic studies based on Lineweaver–Burk inhibition plots. Leaf and tuber extracts acted as mixed-type and competitive inhibitors of α-glucosidase, respectively; the leaf extract demonstrated an uncompetitive inhibition mode of acetylcholinesterase. It is expected that this new knowledge of D. caucasica will serve for its valorization in developing new health beneficial ingredients for functional foods and nutraceuticals.

Dioscorea species, known as “Yams”, belong to the Dioscoreaceae family. Members of the Dioscoreaceae family are widely distributed across subtropical and tropical regions. They are notable for their high content of starch, dietary fiber, and various bioactive compounds. In addition to serving as a staple food source, these tubers possess significant medicinal value in traditional medicine, particularly for treating diabetes, diarrhea, and various inflammatory diseases. This study aimed to comprehensively summarize the active components and food development potential of Dioscorea species from research over the past decade by searching commonly used databases such as PubMed, Web of Science, Scopus, and Google Scholar. This review highlights the classification of bioactive compounds in Dioscorea spp. using the NPClassifier tool. We discuss 60 representative bioactive metabolites, including terpenoids, phenylpropanoids, carbohydrates, fatty acids, alkaloids, and amino acids. Additionally, we discuss the functional food applications and regulations of Dioscorea spp., which possess antioxidant, anti-inflammatory, anti-diabetic, and anticancer properties. This review is expected to provide scientific ideas for future research related to prioritizing the optimization of extraction technologies, the execution of rigorous clinical trials to confirm therapeutic effects, and the exploration of novel applications of Dioscorea spp. bioactives to fully harness their potential in improving human health.

Dioscorea deltoidea Wall. ex Griseb. is an endangered species of the Dioscoreaceae family. It is the most commonly consumed wild species as a vegetable due to its high protein, vital amino acid, vitamin, and mineral content. There are approximately 613 species in the genus Dioscorea Plum. ex L., which is found in temperate and tropical climates. Dioscorea deltoidea, a plant species widespread across tropical and sub-tropical regions, called by different names in different languages. In English, it is commonly referred to as “Wild yam” or “Elephant foot”. The Sanskrit name for this plant is “Varahikand,” while in Hindi, it is known as “Gun” or “Singly-mingly.” The Urdu language refers to it as “Qanis,” and in Nepali, it is called “Tarul,” “Bhyakur,” or “Ghunar.” Dioscorea deltoidea has been used to cure a wide range of human ailments for centuries. This plant has nutritional and therapeutic uses and also contains high amounts of steroidal saponins, allantoin, polyphenols, and most notably, polysaccharides and diosgenin. These bioactive chemicals have shown potential in providing protection against a wide spectrum of inflammatory conditions, including enteritis (inflammation of the intestines), arthritis (joint inflammation), dermatitis (skin inflammation), acute pancreatitis (inflammation of the pancreas), and neuro inflammation (inflammation in the nervous system). Furthermore, the valuable bioactive chemicals found in D. deltoidea have been associated with a range of beneficial biological activities, such as antibacterial, antioxidant, anti-inflammatory, immunomodulatory, hepatoprotective, and cytotoxic properties. Sapogenin steroidal chemicals are highly valued in the fields of medicine, manufacturing, and commerce. It has both expectorant and sedative properties. It is employed in the treatment of cardiovascular diseases, encompassing various ailments related to the heart and blood vessels, skin disease, cancer, immune deficiencies, and autoimmune diseases. Additionally, it finds application in managing disorders of the central nervous system and dysfunctional changes in the female reproductive system. Furthermore, it is valued for its role in treating bone and joint diseases. Metabolic disorders are also among the ailments for which D. deltoidea is employed. It has traditionally been used as a vermifuge, fish poison, and to kill lice. Diosgenin, a steroidal compound found in D. deltoidea, plays a crucial role as a precursor in the chemical synthesis of various hormones. Due to the presence of valuable bioactive molecule, like corticosterone and sigmasterol, D. deltoidea is cultivated specifically for the extraction of these beneficial phytochemicals. The current study aims to assess D. deltoidea's medicinal properties, ethnobotanical usage, phytochemicals, pharmacological properties, threats, and conservation techniques.

Steroidal saponins, which exhibit multiple pharmacological effects, are the major bioactive constituents in herbal medicines from Dioscoreae species. In this study, a sensitive method …

Dioscorea opposita Thunb. cv. Tiegun (DTT) is used daily as food and medicine. However, there is confusion in removing the red flesh of DTT (RF), as the nutrient phytochemicals of RF are unclear. This study aimed to reveal the phytochemicals and antioxidant capabilities of RF. An ultra-high-performance liquid chromatography-quadrupole Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) approach was employed to determine the comprehensive phytochemicals of RF, and the antioxidant activities (DPPH, ABTS, and FRAP) of the extracts were evaluated. A total of 249 phytochemicals were detected, including 150 primary metabolites, 68 secondary metabolites, and 31 other compounds. Notably, 166 differential metabolites (163 upregulated) were identified in RF relative to WF (white flesh). RF significantly increased the contents of primary metabolites (such as lipids, organic acids, and amino acids) and secondary metabolites (such as flavonoids and phenolic acids). RF showed higher antioxidant activity (DPPH, ABTS, and FRAP) than WF. The correlation analysis identified that most of the differential metabolites were significantly positively correlated with the antioxidant capacity. This is the first systematic and comprehensive qualitative analysis of the phytochemicals of RF. This study expands our knowledge of the bioactive constituents of RF and highlights the potential nutritional and medicinal values of DTT.

… The new hybrids of Dioscorea alata exhibited contrasted susceptibility to browning in relation to their total phenolic content (r = 0.91). The detailed polyphenol profiles of “INRA15”, …

… Sophisticated analytical methods such as HPLC and LC-MS could be utilized to overcome this and … Phytochemicals present in dioscorea bulbifera like diosbulbins and flavonoids show …

Abstract Wild yams (Dioscorea spp.) are medicinal plants rich in secondary metabolites of pharmacological interest, mostly allantoin and steroidal saponins. Their natural populations are overexploited and endangered. Cultivated yams could represent an alternative source of metabolites if interesting varieties could be selected. The objectives of the present study were to develop an HPTLC protocol for the simultaneous quantification of allantoin and steroidal saponins in dried yam powders, to compare species and varieties originating from distant geographical origins and to assess their potential as a source of secondary metabolites. Overall, 1151 accessions belonging to six cultivated species were analysed (1000 acc. from Nigeria, and 146 acc. from Vanuatu) and were compared to five commercial powders of wild yam (D. villosa). Allantoin, dioscin, gracillin, protodioscin, protogracillin and five unknown saponins were quantified. Dioscorea villosa powders varied in content and composition, with allantoin ranging from 0.23 to 22.35 mg/g (DW) and total saponins from 37.36 to 129.97 mg/g. Allantoin was present in the six species, with highest values in D. bulbifera bulbils (20.38 mg/g) and D. cayenensis tubers (17.12 mg/g). Steroidal saponins were quantified in three species, D. cayenensis, D. esculenta and D. rotundata, but were absent in D. alata, D. bulbifera and D. dumetorum. Mean total saponins contents were 42.15 mg/g in D. cayenensis, 17.65 mg/g in D. esculenta and 17/44 mg/g in D. rotundata, with accessions presenting very high values in D. cayenensis (78.31 mg/g) and D. rotundata (69.65 mg/g). For both allantoin and saponins, variation was observed within tubers and the tuber peel was richer than the flesh. Cultivated yam species represent a sustainable source of allantoin and steroidal saponins which could be further increased through conventional breeding.

With the aging process, a loss of skeletal muscle mass and dysfunction related to metabolic syndrome is observed in older people. Yams are commonly use in functional foods and medications with various effects. The present study was conducted to investigate the effects of rhizome extract of Dioscorea batatas (Dioscoreae Rhizoma, Chinese yam) and its bioactive compound, allantoin, on myoblast differentiation and mitochondrial biogenesis in skeletal muscle cells. Yams were extracted in water and allantoin was analyzed by high performance liquid chromatography (HPLC). The expression of myosin heavy chain (MyHC) and mitochondrial biogenesis-regulating factors, peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), sirtuin-1 (Sirt-1), nuclear respiratory factor-1 (NRF-1) and transcription factor A, mitochondrial (TFAM), and the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) were determined in C2C12 myotubes by reverse transcriptase (RT)-polymerase chain reaction (RT-PCR) or western blot. The glucose levels and total ATP contents were measured by glucose consumption, glucose uptake and ATP assays, respectively. Treatment with yam extract (1 mg/mL) and allantoin (0.2 and 0.5 mM) significantly increased MyHC expression compared with non-treated myotubes. Yam extract and allantoin significantly increased the expression of PGC-1α, Sirt-1, NRF-1 and TFAM, as well as the phosphorylation of AMPK and ACC in C2C12 myotubes. Furthermore, yam extract and allantoin significantly increased glucose uptake levels and ATP contents. Finally, HPLC analysis revealed that the yam water extract contained 1.53% of allantoin. Yam extract and allantoin stimulated myoblast differentiation into myotubes and increased energy production through the upregulation of mitochondrial biogenesis regulators. These findings indicate that yam extract and allantoin can help to prevent skeletal muscle dysfunction through the stimulation of the energy metabolism.

… The major component of the DRWE, allantoin, was measured using high-performance liquid … The HPLC analysis conducted in the present study confirmed the presence of allantoin in …

Bulbil germination is crucial to the survival of Chinese yam plants, the preservation of germplasm resources and the worldwide supply of food and natural medicine. There are still some unknowns regarding bulbil biochemical variations associated with germination. The metabolic changes during the germination of Chinese yam (Dioscorea polystachya Turczaninow) bulbils were studied using ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) at eight-time points covering all four phases of germination. It was determined that 27 metabolites, including organic acids, amino acids, sugars, lipid metabolites, phenolics and steroids, were responsible for the variation in the Chinese yam bulbil groups. A metabolomics pathway was proposed based on the identified metabolites. The main processes affected during germination were those related to carbohydrate metabolism, the TCA cycle, lipid metabolism, nitrogen metabolism, lipid metabolism and polyphenol metabolism. It is one of the earliest reports on the metabolite identification and profiling of Chinese yam bulbils at different germination stages.

Dioscorea spp. belongs to the Dioscoreaceae family, known as “yams”, and contains approximately 600 species with a wide distribution. It is a major food source for millions of people in tropical and subtropical regions. Dioscorea has great medicinal and therapeutic capabilities and is a potential source of bioactive substances for the prevention and treatment of many diseases. In recent years, increasing attention has been paid to the phytochemicals of Dioscorea, such as steroidal saponins, polyphenols, allantoin, and, in particular, polysaccharides and diosgenin. These bioactive compounds possess anti-inflammatory activity and are protective against a variety of inflammatory diseases, such as enteritis, arthritis, dermatitis, acute pancreatitis, and neuroinflammation. In addition, they play an important role in the prevention and treatment of metabolic diseases, including obesity, dyslipidemia, diabetes, and non-alcoholic fatty liver disease. Their mechanisms of action are related to the modulation of a number of key signaling pathways and molecular targets. This review mainly summarizes recent studies on the bioactive compounds of Dioscorea and its treatment of inflammatory and metabolic diseases, and highlights the underlying molecular mechanisms. In conclusion, Dioscorea is a promising source of bioactive components and has the potential to develop novel natural bioactive compounds for the prevention and treatment of inflammatory and metabolic diseases.

Yams (Discorea spp) are food security crops which serve as invaluable food sources of energy, micronutrients and phytochemicals with numerous health benefits. They show a lot of genetic and compositional diversity. New biologically active compounds are being identified from wild yams. This review focuses on the nutrients, and phytochemicals found in yam species and their health benefits. The B group of vitamins, vitamin C, pro-vitamin A; copper; manganese; isoflavones; steroidal saponins; alkaloids; terpenes; and anthocyanidins are found in different species of yams. Wild yams such as Discorea villosa and Discorea hispida are used in ethnomedicine because of their phytochemical content. Diosgenin, dioscorin, dioscin dihydrodiscorine protodioscin, methyprotodioscin, prosapogenin, epifzelechin, glucopyranoside, phytoestrogen and allantoin are bioactive phytochemicals that may be found in yams. They are valuable as anti-cancer, anti-mutagenic, anti-inflammatory, anti-diabetic, anti-ageing lipid lowering and hepatoprotective agents. Other claims based on traditional uses of yams have not been scientifically substantiated. Dioscorea species are likely to contain other unidentified secondary metabolites. Discorea species with other health promoting bioactive compounds should be identified; modern techniques should be used to extract yet unidentified compounds in Discorea and the food use and health benefits of yam species should be optimized.

Dioscorea polystachya, named Chinese yam, is widely cultivated as a functional food and natural medicine in China. There is currently little information about the chemical characteristics of Dioscorea polystachya in different organs (tuber cortex and tuber flesh) and at various ages. In this study, an ultra‐high‐performance liquid chromatography coupled to quadrupole time‐of‐flight mass spectrometry (UPLC‐QTOF/MS) was used to profile chemical compounds in Dioscorea polystachya. As a result, thirty‐eight compounds were detected in yam tuber cortex and tuber flesh. More compounds were detected in yam tuber cortex than in tuber flesh. Compounds such as dehydroepiandrosterone, allantoin and flavonoids were selected as biomarker candidates. Dehydroepiandrosterone was found more abundant in tuber flesh, while allantoin and flavonoids showed higher levels in tuber cortex. Furthermore, the levels of dioscin, malvalic acid and sucrose differed significantly among age groups and were highest in the tubers at 2 years. While the levels of allantoin, adenosine and glutamine increased with the growing years and were highest at 4 years. Thus, 2‐year old Dioscorea polystachya tubers could be harvested to prepare dioscin, malvalic acid and sucrose supplements. The 4‐year‐old Dioscorea polystachya tubers would be the best choice for obtaining a large amount of allantoin and adenosine in industrial production.

The Chinese yam (Dioscorea polystachya Turcz.) is an underutilized orphan tuber crop. However, in China it has been used in traditional medicine and food for centuries due to the presence of high starch, protein, fiber, and biologically active compounds. Knowledge on the metabolomic profiles of Chinese yam varieties is needed to explore the underutilized metabolites and variety specific uses. Here, the metabolome of eight Chinese yam varieties that are cultivated in different Chinese regions was profiled. A total of 431 metabolites belonging to different biochemical classes was detected. The majority of detected metabolites were classified as amino acids and derivatives. The different yam varieties offer unique uses; e.g., Hebei Ma Yam, Henan Huai Yam, and Henan Wild Yam were the most metabolically enriched and suitable as food and medicine. Yams from Hubei region had comparable nutritional profiles, which is most probably due to their geographical origin. Specifically, Henan Wild Yam had the highest concentrations of diosgenin, vitamins, and polysaccharides. Overall, this study presents a metabolome reference for D. polystachya varieties.

… –metabolite–microbe interactions are crucial for crop health and quality. Yam (Dioscorea spp.… However, the mechanisms by which different yam species regulate metabolite–microbiome …

… Dioscorea is as an emerging model … Dioscorea is rich in secondary metabolite content (eg, diosgenin). The first objective of this study was phylogenetic analysis of Indian Dioscorea. …

… (Dioscorea spp.) is … metabolomic, and transcriptomic analysis of yam tubers. The results showed that the tuber weight increased with the accumulation of starch, and sucrose metabolism …

Yams are economic and medicinal crops with a long growth cycle, spanning between 9–11 months due to their prolonged tuber dormancy. Tuber dormancy has constituted a major constraint in yam production and genetic improvement. In this study, we performed non-targeted comparative metabolomic profiling of tubers of two white yam genotypes, (Obiaoturugo and TDr1100873), to identify metabolites and associated pathways that regulate yam tuber dormancy using gas chromatography–mass spectrometry (GC–MS). Yam tubers were sampled between 42 days after physiological maturity (DAPM) till tuber sprouting. The sampling points include 42-DAPM, 56-DAPM, 87DAPM, 101-DAPM, 115-DAPM, and 143-DAPM. A total of 949 metabolites were annotated, 559 in TDr1100873 and 390 in Obiaoturugo. A total of 39 differentially accumulated metabolites (DAMs) were identified across the studied tuber dormancy stages in the two genotypes. A total of 27 DAMs were conserved between the two genotypes, whereas 5 DAMs were unique in the tubers of TDr1100873 and 7 DAMs were in the tubers of Obiaoturugo. The differentially accumulated metabolites (DAMs) spread across 14 major functional chemical groups. Amines and biogenic polyamines, amino acids and derivatives, alcohols, flavonoids, alkaloids, phenols, esters, coumarins, and phytohormone positively regulated yam tuber dormancy induction and maintenance, whereas fatty acids, lipids, nucleotides, carboxylic acids, sugars, terpenoids, benzoquinones, and benzene derivatives positively regulated dormancy breaking and sprouting in tubers of both yam genotypes. Metabolite set enrichment analysis (MSEA) revealed that 12 metabolisms were significantly enriched during yam tuber dormancy stages. Metabolic pathway topology analysis further revealed that six metabolic pathways (linoleic acid metabolic pathway, phenylalanine metabolic pathway, galactose metabolic pathway, starch and sucrose metabolic pathway, alanine-aspartate-glutamine metabolic pathways, and purine metabolic pathway) exerted significant impact on yam tuber dormancy regulation. This result provides vital insights into molecular mechanisms regulating yam tuber dormancy.

… Diosgenin is a plant-derived secondary metabolite mainly present in the members of the plant … studies and future direction of research on production of diosgenin from Dioscorea spp. …

… The objectives of the present study were to analyze saponins and … Dioscin and gracillin, the most documented Dioscorea … bioactive saponin found in wild Dioscorea spp. (Zhang et al. …

Breast cancer is among the most commonly diagnosed cancer and the leading cause of cancer-related death among women globally. Malaysia is a country that is rich in medicinal plant species. Hence, this research aims to explore the secondary metabolites, antioxidant, and antiproliferative activities of Dioscorea bulbifera leaf collected from Endau Rompin, Johor, Malaysia. Antioxidant activity was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) assays, while the cytotoxicity of D. bulbifera on MDA-MB-231 and MCF-7 breast cancer cell lines was tested using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Cell cycle analysis and apoptosis were assessed using flow cytometry analysis. Phytochemical profiling was conducted using gas chromatography-mass spectrometry (GC-MS). Results showed that methanol extract had the highest antioxidant activity in DPPH, FRAP, and ABTS assays, followed by ethyl acetate and hexane extracts. D. bulbifera tested against MDA-MB-231 and MCF-7 cell lines showed a pronounced cytotoxic effect with IC50 values of 8.96 μg/mL, 6.88 μg/mL, and 3.27 μg/mL in MCF-7 and 14.29 μg/mL, 11.86 μg/mL, and 7.23 μg/mL in MDA-MB-231, respectively. Cell cycle analysis also indicated that D. bulbifera prompted apoptosis at various stages, and a significant decrease in viable cells was detected within 24 h and substantially improved after 48 h and 72 h of treatment. Phytochemical profiling of methanol extract revealed the presence of 39 metabolites such as acetic acid, n-hexadecanoic acid, acetin, hexadecanoate, 7-tetradecenal, phytol, octadecanoic acid, cholesterol, palmitic acid, and linolenate. Hence, these findings concluded that D. bulbifera extract has promising anticancer and natural antioxidant agents. However, further study is needed to isolate the bioactive compounds and validate the effectiveness of this extract in the In in vivo model.