The Dioscorea Genus (Yam)-An Appraisal of Nutritional and Therapeutic Potentials

Medicinal and edible plants in the treatment of dyslipidemia: advances and prospects

Dyslipidemia is an independent risk factor of cardiovascular diseases (CVDs), which lead to the high mortality, disability, and medical expenses in the worldwide. Based on the previous researches, the improvement of dyslipidemia could efficiently prevent the occurrence and progress of cardiovascular diseases. Medicinal and edible plants (MEPs) are the characteristics of Chinese medicine, and could be employed for the disease treatment and health care mostly due to their homology of medicine and food. Compared to the lipid-lowering drugs with many adverse effects, such as rhabdomyolysis and impaired liver function, MEPs exhibit the great potential in the treatment of dyslipidemia with high efficiency, good tolerance and commercial value. In this review, we would like to introduce 20 kinds of MEPs with lipid-lowering effect in the following aspects, including the source, function, active component, target and underlying mechanism, which may provide inspiration for the development of new prescription, functional food and complementary therapy for dyslipidemia.

Zygo-Albuside A: New Saponin from Zygophyllum album L. with Significant Antioxidant, Anti-Inflammatory and Antiapoptotic Effects against Methotrexate-Induced Testicular Damage

Chemical investigation of the crude extract of the aerial part of Zygophyllum album L. (Z. album) led to the isolation of a new saponin, Zygo-albuside A (7), together with seven known compounds, one of them (caffeic acid, compound 4) is reported in the genus for the first time. NMR (1D and 2D) and mass spectrometric analysis, including high-resolution mass spectrometry (HRMS), were utilized to set up the chemical structures of these compounds. The present biological study aimed to investigate the protective antioxidant, anti-inflammatory, and antiapoptotic activities of the crude extract from the aerial part of Z. album and two of its isolated compounds, rutin and the new saponin zygo-albuside A, against methotrexate (MTX)-induced testicular injury, considering the role of miRNA-29a. In all groups except for the normal control group, which received a mixture of distilled water and DMSO (2:1) as vehicle orally every day for ten days, testicular damage was induced on the fifth day by intraperitoneal administration of MTX at a single dose of 20 mg/kg. Histopathological examination showed that pre-treatment with the crude extract of Z. album, zygo-albuside A, or rutin reversed the testicular damage induced by MTX. In addition, biochemical analysis in the protected groups showed a decrease in malondialdehyde (MDA), interleukin-6 (IL-6) and IL-1β, Bcl-2-associated-protein (Bax), and an increase in B-cell lymphoma 2 (Bcl-2) protein, catalase (CAT), superoxide dismutase (SOD) in the testis, along with an increase in serum testosterone levels compared with the unprotected (positive control) group. The mRNA expression levels of nuclear factor-kappa B (NF-κB), tumor necrosis factor-α (TNF-α), p53, and miRNA-29a were downregulated in the testicular tissues of the protected groups compared with the unprotected group. In conclusion, the study provides sufficient evidence that Z. album extract, and its isolated compounds, zygo-albuside A and rutin, could alleviate testicular damage caused by the chemotherapeutic agent MTX.

Development and Validation of Quantitative Analysis Method for Phenanthrenes in Peels of the Dioscorea Genus

Phenanthrenes are bioactive phenolic compounds found in genus Dioscorea, in which they are distributed more in peel than in flesh. Recent studies on phenanthrenes from Dioscorea sp. peels have revealed the potential for valuable biomaterials. Herein, an analytical method using high-performance liquid chromatography (HPLC) for quantitation of bioactive phenanthrenes was developed and validated. The calibration curves were obtained using the phenanthrenes (1-3) previously isolated from Dioscorea batatas concentrations in the range of 0.625-20.00 μg/ml with a satisfactory coefficient of determination (R2) of 0.999. The limit of detection (LOD) and the limit of quantification (LOQ) values of the isolated phenanthrenes ranged from 0.78-0.89 and 2.38-2.71 μg/ml, respectively. The intraday and interday precision ranged from 0.25-7.58%. The recoveries of the isolated phenanthrenes were from 95 to 100% at concentrations of 1.25, 2.5, and 5.0 μg/ml. Additionally, phenanthrenes (1-3) were found in all investigated peel extracts. Hence, the developed method was encouraging for the quantitative analysis of phenanthrenes in genus Dioscorea.

Could consumption of yam (Dioscorea) or its extract be beneficial in controlling glycaemia: a systematic review

Yam (Dioscorea spp.) and its associated extracts have been shown to possess a variety of biological activities and identified as beneficial in the control of glycaemia in patients with type II diabetes mellitus (T2DM). The objective was to conduct a systematic search of the literature to investigate whether yam and its extract can improve glycaemia and whether the consumption of yam could be beneficial for managing T2DM. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and the Population, Invention, Comparison and Outcome framework, three databases (PubMed, Scopus and Web of Science) were searched using a key term strategy. Strict inclusion criteria were employed to identify all relevant and available studies. The quality of these studies was assessed using SYRCLE's Risk of Bias tool. Ten studies were included, and all studies consisted of findings from rodent models of diabetes, including animals consuming high fat diets or genetic models of diabetes. All ten studies showed that the consumption of yam and/or its extracts (containing dioscin, dioscorin, diosgenin, DA-9801/02 or Chinese yam polysaccharides) improved glycaemia. These included improvements in fasting blood glucose and reductions in glucose and increase in insulin levels following a glucose tolerance test. Furthermore, significant changes in body weight and adiposity were observed in nine studies, these included improvements in lipid biomarkers in four and reductions in inflammatory markers in one. The current work indicates that the consumption of yam or its extracts can be beneficial for improving blood glucose; however, the molecular mechanism for these effects remains largely unknown. Future trials on human subjects are warranted.

Viruses of Yams (Dioscorea spp.): Current Gaps in Knowledge and Future Research Directions to Improve Disease Management

Viruses are a major constraint for yam production worldwide. They hamper the conservation, movement, and exchange of yam germplasm and are a threat to food security in tropical and subtropical areas of Africa and the Pacific where yam is a staple food and a source of income. However, the biology and impact of yam viruses remains largely unknown. This review summarizes current knowledge on yam viruses and emphasizes gaps that exist in the knowledge of the biology of these viruses, their diagnosis, and their impact on production. It provides essential information to inform the implementation of more effective virus control strategies.

Response of Yam (Dioscorea alata) to the Application of Rhizophagus irregularis and Potassium Silicate under Salinity Stress

Yam (Dioscorea alata) is a tropical plant that is considered critical for food security. The use of high fertilizer, low soil fertility, and insect pest infestation reduce yam tuber yield and quality. The present study was performed to determine the effect of potassium silicate and arbuscular mycorrhizal fungi (AMF) on yam cultivated under salinity stress. This study revealed that the combination of Rhizophagus irregularis (AMF) and Potassium silicate was more effective than their individual application on yam and were beneficial for overall analyzed characters. We observed the days to emergence and the average days to first leaf emergence decreased by 33.46% and 26.78%, respectively, the number of leaves increased by 45.23%, number of sprouts per seed tuber by 50%, vine length by 60.8%, vine length at harvest by 40.53%, the average leaf width by 53.79%, petiole length by 31.74%, tuber length by 43.84%, average diameter of tuber by 56.58%, and average number of tuber per vine by 46.15% in T5 treated plants. We also recorded that starch content increased by 21.89%, ascorbic acid by 61.51%, average moisture by 8.36%, TSS by 50%, and total sugar by 69.53% in T5 treated plants. The total phenol was found to be 1.53% higher in T3 applied plants, while the dry matter was 36.37% higher in T5 treatment. Furthermore, the enzymatic evaluation of MDA in leaves was found to be enhanced by 142% in T2. The enzyme 8-OHdG from the leaves sample was reported to be increased after T5 by 621.15%. Moreover, the amount of CAT was higher by 53.46% in T2 treated plants. Likewise, the amount of enzyme SOD and POX in leaves of D. alata enhanced by 30.91% and 51.15% T2 treatments respectively.

Genome Editing for Sustainable Agriculture in Africa

Sustainable intensification of agriculture in Africa is essential for accomplishing food and nutritional security and addressing the rising concerns of climate change. There is an urgent need to close the yield gap in staple crops and enhance food production to feed the growing population. In order to meet the increasing demand for food, more efficient approaches to produce food are needed. All the tools available in the toolbox, including modern biotechnology and traditional, need to be applied for crop improvement. The full potential of new breeding tools such as genome editing needs to be exploited in addition to conventional technologies. Clustered regularly interspaced short palindromic repeats/CRISPR-associated protein (CRISPR/Cas)-based genome editing has rapidly become the most prevalent genetic engineering approach for developing improved crop varieties because of its simplicity, efficiency, specificity, and easy to use. Genome editing improves crop variety by modifying its endogenous genome free of any foreign gene. Hence, genome-edited crops with no foreign gene integration are not regulated as genetically modified organisms (GMOs) in several countries. Researchers are using CRISPR/Cas-based genome editing for improving African staple crops for biotic and abiotic stress resistance and improved nutritional quality. Many products, such as disease-resistant banana, maize resistant to lethal necrosis, and sorghum resistant to the parasitic plant Striga and enhanced quality, are under development for African farmers. There is a need for creating an enabling environment in Africa with science-based regulatory guidelines for the release and adoption of the products developed using CRISPR/Cas9-mediated genome editing. Some progress has been made in this regard. Nigeria and Kenya have recently published the national biosafety guidelines for the regulation of gene editing. This article summarizes recent advances in developments of tools, potential applications of genome editing for improving staple crops, and regulatory policies in Africa.

Dioscorea spp.: Comprehensive Review of Antioxidant Properties and Their Relation to Phytochemicals and Health Benefits

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.

Chromosome evolution and the genetic basis of agronomically important traits in greater yam

The nutrient-rich tubers of the greater yam, Dioscorea alata L., provide food and income security for millions of people around the world. Despite its global importance, however, greater yam remains an orphan crop. Here, we address this resource gap by presenting a highly contiguous chromosome-scale genome assembly of D. alata combined with a dense genetic map derived from African breeding populations. The genome sequence reveals an ancient allotetraploidization in the Dioscorea lineage, followed by extensive genome-wide reorganization. Using the genomic tools, we find quantitative trait loci for resistance to anthracnose, a damaging fungal pathogen of yam, and several tuber quality traits. Genomic analysis of breeding lines reveals both extensive inbreeding as well as regions of extensive heterozygosity that may represent interspecific introgression during domestication. These tools and insights will enable yam breeders to unlock the potential of this staple crop and take full advantage of its adaptability to varied environments.

Clinical Efficacy of Yiqi Yangyin Decoction Combined with Docetaxel on Advanced Ovarian Cancer and the Effect on the Levels of Serum Markers VEGF, HE4, and CA125

Objective

The study is designed to investigate the therapeutic effect of Yiqi Yangyin Decoction combined with docetaxel on advanced ovarian cancer (OC) patients and the effects on serum markers VEGF, HE4, and CA125.

Methods

92 patients with advanced OC were grouped into the study group and control group. The control group was given the treatment of basic chemotherapy combined with docetaxel. The study group was added the treatment of Yiqi Yangyin Decoction on the basis of the control group. The short-term efficacy, adverse reactions, tumor markers, quality of life, 3-year survival, and T cell subsets of the two groups were observed.

Results

Compared to the control group, the study group's incidence of adverse reactions was lower. VEGF, HE4, and CA125 in the study group were decreased more obviously. The levels of CD3⁺, CD4⁺, and CD4⁺/CD8⁺ were sharply higher in the study group, while CD8⁺ was notably reduced. After treatment, the scores of physical health, social function, and mental health in the study group were notably higher than those in the control group. Compared with the control group, the 3-year survival rate of the study group was notably higher, and the therapeutic effect of the study group was obviously better.

Conclusion

The combination of Yiqi Yangyin Decoction and docetaxel can improve the body immunity and the therapeutic effect of advanced OC, decrease the incidence of adverse reactions, and prolong the survival time, with good safety and effectiveness.

Neglected and Underutilised Crops: A Systematic Review of Their Potential as Food and Herbal Medicinal Crops in South Africa

The African continent harbours many native species with nutraceutical and pharmaceutical potential. This study reviewed underutilised crops in South Africa to determine their potential as food and herbal medicinal crops. Over 5,000 species have been identified and earmarked for their medical attributes in formal and informal setups. Researchers, plant breeders and policymakers have mostly ignored the development potential of these crops. Consequently, their value chains are poorly developed. In South Africa, there is a wide range of neglected and underutilised crops, which were historically popular and used by communities; however, over the years, they have lost their status within farming systems and been relegated to the status of neglected and underutilised. Recently, driven by the need to transition to more sustainable and resilient food systems, there has been renewed interest in their potential as food and herbal medicinal crops to establish new value chains that include vulnerable groups. They are now gaining global attention, and their conservation and sustainable utilisation are now being prioritized. The review confirmed that several of these crops possess nutraceutical and pharmaceutical properties, highlighting their potential for development as food and herbal medicines. However, current production levels are too low to meet the requirements for industrial development; research and development should focus on all aspects of their value chain, from crop improvement to utilisation. A transdisciplinary approach involving a wide range of actors is needed to develop the identified neglected and underutilised crops' potential as food and herbal medicinal crops and support the development of new and inclusive value chains.

Anti-neuroinflammatory activity of 6,7-dihydroxy-2,4-dimethoxy phenanthrene isolated from Dioscorea batatas Decne partly through suppressing the p38 MAPK/NF-κB pathway in BV2 microglial cells

ETHNOPHARMACOLOGICAL RELEVANCE

The rhizome of Dioscorea batatas Decne (called Chinses yam) widely distributed in East Asian countries including China, Japan, Korea and Taiwan has long been used in oriental folk medicine owing to its tonic, antitussive, expectorant and anti-ulcerative effects. It has been reported to have anti-inflammatory, antioxidative, cholesterol-lowering, anticholinesterase, growth hormone-releasing, antifungal and immune cell-stimulating activities.

AIM OF THE STUDY

Neuroinflammation caused by activated microglia contributes to neuronal dysfunction and neurodegeneration. In the present study, the anti-neuroinflammatory activity of 6,7-dihydroxy-2,4-dimethoxy phenanthrene (DHDMP), a phenanthrene compound isolated from Dioscorea batatas Decne, was examined in microglial and neuronal cells.

MATERIALS AND METHODS

A natural phenanthrene compound, DHDMP, was isolated from the peel of Dioscorea batatas Decne. The anti-neuroinflammatory capability of the compound was examined using the co-culture system of BV2 murine microglial and HT22 murine neuronal cell lines. The expression levels of inflammatory mediators and cytoprotective proteins in the cells were quantified by enzyme-linked immunosorbent assay and Western blot analysis.

RESULTS

DHDMP at the concentrations of ≤1 μg/mL did not exhibit a cytotoxic effect for BV2 and HT22 cells. Rather DHDMP effectively restored the growth rate of HT22 cells, which was reduced by co-culture with lipopolysaccharide (LPS)-treated BV2 cells. DHDMP significantly decreased the production of proinflammatory mediators, such as nitric oxide, tumor necrosis factor-α, interleukin-6, inducible nitric oxide synthase, and cyclooxygenase-2 in BV2 cells. Moreover, DHDMP strongly inhibited the nuclear translocation of nuclear factor κB (NF-κB) and phosphorylation of p38 mitogen-activated protein kinase (MAPK) in BV2 cells. The compound did not affect the levels and phosphorylation of ERK and JNK. Concurrently, DHDMP increased the expression of heme oxygenase-1 (HO-1), an inducible cytoprotective enzyme, in HT22 cells.

CONCLUSIONS

Our findings indicate that DHDMP effectively dampened LPS-mediated inflammatory responses in BV2 microglial cells by suppressing transcriptional activity of NF-κB and its downstream mediators and contributed to HT22 neuronal cell survival. This study provides insight into the therapeutic potential of DHDMP for inflammation-related neurological diseases.

Clinical Effects of Integrated Traditional Chinese and Western Medicine in Treating Severe Preeclampsia and Its Influence on Maternal and Infant Outcomes after Cesarean Section under Combined Lumbar and Epidural Anesthesia

Objective

This study is aimed to observe the clinical effects of integrated traditional Chinese and Western medicine in treating severe preeclampsia (SPE) and its effects on maternal and infant outcomes after cesarean section under combined lumbar and epidural anesthesia.

Method

One hundred and sixty-six pregnant women with SPE were randomly divided into an experimental group and control group, with 83 cases in each group. The control group was given conventional treatments such as magnesium sulfate, and the experimental group received self-made traditional Chinese medicine decoction for oral administration.

Results

The total clinical effective rate of treatment in the experimental group was significantly higher than that in the control group. After treatment, the systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and 24 h proteinuria (24 h PRO) levels of the experimental group were significantly lower than those of the control group. After cesarean section (c-section) under combined lumbar and epidural anesthesia, there were statistically significant differences in placental abruption, uterine weakness, fetal intrauterine distress, and neonatal asphyxia in the experimental group, while there were no significant differences in oligohydramnios. After treatment, the contents of inflammatory factors in both groups decreased, and the decrease was more prominent in the experimental group. After treatment, the levels of blood urea nitrogen (BUN), serum creatinine (Scr), and albumin (Alb) and β2 microglobulin (β2-MG) of the two groups of patients decreased, and the levels of them in the experimental group decreased. After treatment, the levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in the two groups increased. However, the levels of malondialdehyde (MDA), lipid peroxide (LPO), and advanced oxidation protein products (AOPP) all reduced, and the increase or decrease in the experimental group was more prominent.

Conclusion

The combination of traditional Chinese and Western medicine can reduce the blood pressure of a patient with SPE. After the combined spinal-epidural anesthesia and cesarean section, it can significantly improve the maternal and infant outcomes and renal function, reduce inflammatory factors levels and body oxidative stress, and increase the activities of antioxidant enzymes.

Zanzibar yam (Dioscorea sansibarensis Pax) isolates exhibit cyclooxygenase enzyme and lipid peroxidation inhibitory activities

Several phenanthrenes (1-5), phenolics (6-8) and steroidal sapogenins (9-11) were isolated for the first time from the aqueous and methanolic extracts of Dioscorea sansibarensis Pax yam collected from Tanzania. Chemical structures of all the isolates (1-11) were determined by using 1D and 2D nuclear magnetic resonance spectral methods. All pure isolates were evaluated for anti-inflammatory activity using in vitro cyclooxygenase enzyme (COX-1 and -2) inhibitory assays. Among the isolates tested, phenanthrenes 3-5 showed the highest COX-1 and -2 enzyme inhibitory activity whereas phenolics (6-8) and steroidal sapogenins (9-11) exhibited moderate inhibition when compared to non-steroidal anti-inflammatory drugs aspirin, ibuprofen and naproxen. Compounds 6-11 were evaluated for antioxidant activity using lipid peroxidation inhibitory (LPO) assay for the first time and exhibited moderate LPO inhibition.

Dihydroisocoumarins and Dihydroisoflavones from the Rhizomes of Dioscorea collettii with Cytotoxic Activity and Structural Revision of 2,2'-Oxybis(1,4-di-tert-butylbenzene)

The investigation of the constituents of the rhizomes of Dioscorea collettii afforded one new dihydroisocoumarin, named (−)-montroumarin (1a), along with five known compounds—montroumarin (1b), 1,1′-oxybis(2,4-di-tert-butylbenzene) (2), (3R)-3′-O-methylviolanone (3a), (3S)-3′-O-methylviolanone (3b), and (RS)-sativanone (4). Their structures were elucidated using extensive spectroscopic methods. To the best of our knowledge, compound 1a is a new enantiomer of compound 1b. The NMR data of compound 2 had been reported but its structure was erroneous. The structure of compound 2 was revised on the basis of a reinterpretation of its NMR data (1D and 2D) and the assignment of the ¹H and ¹³C NMR data was given rightly for the first time. Compounds 3a–4, three dihydroisoflavones, were reported from the Dioscoreaceae family for the first time. The cytotoxic activities of all the compounds were tested against the NCI-H460 cell line. Two dihydroisocoumarins, compounds 1a and 1b, displayed moderate cytotoxic activities, while the other compounds showed no cytotoxicity.

Metabolite Profiling of Dioscorea (Yam) Leaves to Identify Bioactive Compounds Reveals Their Potential as Renewable Resources

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.

Metabolome Profiling of Eight Chinese Yam (Dioscorea polystachya Turcz.) Varieties Reveals Metabolite Diversity and Variety Specific Uses

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.

Effects of different household cooking methods on the biological properties of Chinese yam

Yam (Dioscorea opposite Thunb) is used as a staple food and a traditional medicine in China. This study investigated the effects of different household cooking methods on the bioactive components (phenolic compounds, diosgenin and allantoin) and their bioaccessibility as well as the biological properties (antioxidant activity, hypoglycemic activity, anti-angiotensin I-converting enzyme (ACE) or anti-acetylcholinesterase (AChE)) of Chinese yam using an in vitro simulated digestion model. The results demonstrated that cooking caused significant losses of total soluble phenolic compounds (lowest loss of 20% for boiling at atmospheric pressure) and diosgenin content (lowest loss of 27.37% for microwaving) but no changes in the allantoin content. The cooking methods affected the bioaccessibility of the bioactive components differently. Normal steaming resulted in the highest amount of bioaccessible phenolic compounds (71.21%) and allantoin (79.07%), whereas high-pressure boiling in the highest content of diosgenin (75.58%). The concentration of bioactive components in the digesta fluid was correlated with the antioxidant activity and enzymatic inhibitory activities. Overall, household cooking processes allow the biological activity of yam to be retained by changing the profile of bioactive components potentially available for intestinal absorption. Thus, a household cooking method such as normal pressure steaming appeared to be most suitable for achieving the expected health benefits of yam.