Chinese Yam Research Articles

Streptomyces sp. 30702 composite chitosan alleviates continuous cropping obstacles in Chinese yam by improving rhizospheric soil microbial environment: A field study in Hainan

Yam is a vital medicinal plant, yet its cultivation faces increasing challenges, particularly due to pathogenic diseases linked to continuous cropping obstacles. This study examines the effects of Streptomyces sp. 30702 and Chitosan on anthracnose and soil microbial communities across four treatment groups: CK (control), SP (Streptomyces sp. 30702), CTS (chitosan), and SC (combined Streptomyces sp. 30702 and Chitosan) within a continuous yam cropping system. The yam was watered every 20 days with 0.25 g plant−1 of chitosan and 4.2 × 10⁵ CFU plant−1 of Streptomyces sp. 30702. Notably, the SC treatment significantly reduced the disease index by 41.31 %, cut root-knot nematode populations by 95.40 %, and boosted yield by 205.45 % compared to CK (P > 0.05). SC treatment also increased soil levels of available nitrogen, phosphorus, potassium, and urease activity. High-throughput sequencing highlighted the dominance of three bacterial phyla (Acidobacteriota, Proteobacteria, and Actinobacteriota) and three fungal phyla (Ascomycota, Basidiomycota, and unidentified Fungi) at harvest. At the bacterial genus level, Bacillus showed a significant increase in SC compared to CK, while LEfSe analysis identified five marker microorganisms in CTS (including Flavobacterium) and four in SC at the fungal genus level. Importantly, SC management reduced the relative abundance of Colletotrichum, the primary cause of anthracnose, by 42.27 % compared to CK. In the Hainan yam continuous cropping system, four Amplicon Sequence Variants (ASVs) were identified as bacterial connectors, two as module hubs, and two as fungal connectors, underscoring their roles in decomposition and environmental adaptability. The results of the Redundancy Analysis (RDA) indicate that available phosphorus in the soil significantly affects the composition of bacterial and fungal communities, with the greatest influence. Additionally, available potassium, available nitrogen, and root-knot nematodes significantly influence the bacterial community, while available nitrogen and root-knot nematodes significantly affect the fungal community (P < 0.05). Overall, the combination of Streptomyces sp. 30702 and chitosan proved to be an effective bio-agent duo, regulating soil microbial communities, reducing anthracnose, and providing a theoretical basis for addressing continuous cropping challenges in yam cultivation.

Carbon accumulation model for simulating 14C radioactivity in Chinese yam grown from a seed bulbil.

Modeling carbon accumulation in crop plants is key to evaluating the transfer of atmospheric 14C into the edible parts of the plants growing near nuclear facilities. Chinese yam 'Nagaimo' (Dioscorea polystachya Turcz.) is a major crop cultivated near a spent nuclear fuel reprocessing plant in Rokkasho, Aomori, Japan. We developed a dynamic compartment model for assessing carbon and 14C accumulation in Chinese yam grown from a seed bulbil in the field. Light and temperature dependence of leaf photosynthesis and temperature dependence of respiration in leaves, stems and belowground parts (tuber and root) were incorporated into the model. Estimated amounts of carbon in the leaves, stems and belowground parts were good agreement with the measured data from the field. Simulation results of 14C accumulation using this model indicated that the accumulation of 14C in belowground parts at the harvest depends on the rate of photosynthesis on the day of exposure.

Investigating the association between dry deposition of cesium and different growth stages of aboveground parts of Chinese yam.

Radiocesium released into the atmosphere from accidents at nuclear facilities, can be deposited on the surface of the surrounding crop fields as dry and wet deposits. Radiocesium deposition can occur at any time during the growth season. In this study, we used stable cesium (Cs) to investigate the changes in dry Cs deposits on surfaces of aboveground parts of Chinese yam (Dioscorea polystachya) during different growth stages. Chinese yam seedlings were grown for eight different lengths of time and were then simultaneously exposed to aerosol particles containing stable Cs in an aerosol exposure chamber for 5h. The deposition density of Cs on the aboveground parts of the seedlings decreased from 29 to 72d after transplantation (DAT) and did not change significantly after 72 DAT. The Cs deposition density on the seedlings on different DAT correlated with the leaf area available for the deposition of aerosol Cs particles.

Investigating Dioscorea polystachya Starch as a Pharmaceutical Excipient

Investigating Dioscorea polystachya Starch as a Pharmaceutical Excipient

Multi-omics analysis reveals the protective effects of Chinese yam polysaccharide against cisplatin-induced renal interstitial fibrosis

BackgroundChinese yam polysaccharide (SYDT) has been reported to protect renal function and mitigate renal fibrosis in mice with diabetic nephropathy. Based on a multi-omics analysis, the objectives of this study were to determine the effect of SYDT on cisplatin (CDDP)-induced chronic renal interstitial fibrosis (RIF) and the underlying molecular mechanisms using an in vivo model. MethodsRats were intraperitoneally injected with a single dose of CDDP and then treated with SYDT or amifostine (AMF). The levels of urinary N-acetyl-β-D-glucosaminidase (NAG), blood urea nitrogen (BUN) and serum creatinine (Scr) were detected to assess renal function. Renal tissue damage and fibrosis were evaluated using hematoxylin and eosin (H&E) and Masson's trichrome staining, respectively. In addition, this study applied transcriptomics and metabolomics to predict the possible mechanism of SYDT action, which was verified by several relevant examinations. ResultsSYDT significantly protected the renal function, alleviated renal tissue damage and fibrosis, as well as decreased the protein levels of vimentin, α-SMA and CTGF, whereas SYDT significantly increased MMP-1 protein level in renal tissues from rats treated with CDDP. There were 1130 differently expressed genes (DEGs) between the CDDP model and SYDT-M groups proved by transcriptome analysis, indicating that metabolic pathways were likely the primary targets of relevance. Consistent with the transcriptome analysis, metabolome analysis identified 276 differentially expressed metabolites (DEMs) between the SYDT-M and CDDP model groups, with predominant clustering within glycerophospholipid metabolism. Integrative analysis of the transcriptome and metabolome indicated that SYDT inhibited the glycerophospholipid metabolism pathway by regulating the target genes Gpd2, Gpam, Agpat3, Lcat, and Pla2g4b. Notably, integrative analysis showed that the Phospholipase D (PLD) signaling pathway may be the most relevant target. Moreover, related signaling pathway analysis confirmed that SYDT inhibited CDDP-induced RIF in rats by down-regulating the PLD pathway. ConclusionOur study showed that the alleviation of CDDP-induced RIF in vivo can be achieved through the inhibition of glycerophospholipid metabolism and PLD signaling pathways by SYDT.

Regulatory effects of yam (Dioscorea opposita Thunb.) glycoprotein on energy metabolism in C2C12 and 3T3-L1 cells and on crosstalk between these two cells

Ethnopharmacological relevanceControlling energy and regulating metabolism have been key strategies in the treatment of metabolic disorders such as obesity. Yam glycoprotein (Y-Gly) is a polysaccharide-protein complex extracted from Chinese yam that has beneficial effects on glucose and lipid metabolism. This study aimed to investigate the role of Y-Gly in regulating energy metabolism in C2C12 and 3T3-L1 cells. Materials and methodsY-Gly was subjected to extraction and chemo-profiling. Staining methods, assay kits, Western Blot and transcriptomics were mainly used to determine the role of Y-Gly. Additionally, the study sought to examine the impact of Y-Gly on white adipose browning in 3T3-L1 cells, employing a cell co-culture technique. ResultsY-Gly promoted myotube differentiation in C2C12 myoblasts, increased cellular glucose consumption, promoted ATP synthesis and mitochondrial biogenesis, and played an active role in energy expenditure and glycolipid metabolism related pathways such as AMPK and MAPK. The introduction of Y-Gly inhibited lipid accumulation after lipogenesis in 3T3-L1 cells, facilitated induction of white adipose browning related proteins such as PPARγ and UCP1 expression, and the effect was more significant after cell co-culture. ConclusionsY-Gly regulates glucose and lipid metabolism by activating the key proteins in the aforementioned pathways, and plays a role in energy metabolism regulation through crosstalk between muscle and adipose tissues. This suggests a possible role of Y-Gly in metabolism-related diseases.

Identification Of Pathogen Causing Wilt Disease Of Chinese Yam (Dioscorea Polystachya Turczaninow) In Hunan

This study aims to identify the pathogen causing wilt disease of Chinese yam (Dioscorea polystachya Turczaninow.) in Hunan Province. Diseased stems were collected from the fields in Loudi City in the Hunan Province. Tissue culture method was used for the isolation of the pathogen causing wilt disease of Chinese yam, and was identified as Fusarium asiaticum based on the morphological characteristics and molecular technology. Out of five fungicides, Difenoconazole· Azoxystrobin 40% SC, Hexaconazole 5% SC, and Difenoconazole 10% WDG, demonstrated inhibitory effects on the pathogen. Among them, hexonazole 5% SC had the lowest EC50 value and was the most sensitive to the pathogen of Chinese yam wilt, so it should be selected first for the control of Chinese yam wilt. Bangladesh J. Bot. 53(3): 857-863, 2024 (September) Special

Targeted and non-targeted metabolic characteristics of 6,7-dihydroxy-2,4- dimethoxyphenanthrene during simulated gastrointestinal digestion

6,7-dihydroxy-2,4-dimethoxyphenanthrene (PC4), isolated and identified from Chinese yam, was one of the important characteristic active ingredients. The present study established simulated gastrointestinal digestion and caco-2 intestinal epithelial models to investigate the digestive and metabolic characteristics of PC4. The results indicated that PC4 was mainly digested and metabolized in the intestine, with a digestion rate of 94 %, producing active characteristic metabolites including 2,6-dimethoxy-4-phenanthrenol (MC1) and 1-methoxyphenanthrene (MC2). Molecular docking indicated that the COX-2 enzyme inhibitory activity of MC1 might be superior to that of the prototype PC4. During 24 h co-incubation of PC4 with caco-2 monolayer epithelial, the signal pathway related to lipid decomposition was up-regulated within 0–12 h, while the diabetes complications AGE-RAGE was inhibited just in 0–6 h period significantly. The research database provided scientific basis for the digestion and metabolism of PC4, and laid theoretical foundation for the scientific development of Chinese yam functional foods.

Chinese yam polysaccharide-loaded aluminium hydroxide nanoparticles used as vaccine adjuvant to induce potent humoral and cellular immune responses

Due to their safety and efficacy, aluminium salts (Alum) are considered the most important adjuvants in human vaccines. However, Alum adjuvants are unable to elicit a cellular immune response, which is vital for the prevention of various chronic infectious diseases and cancers. Herein, we isolated and purified a water-soluble polysaccharide from Chinese yam, named CYP, which was primarily composed of →4)-α-D-Glcp-(1→, →4,6)-α-D-Glcp-(1→, and α-D-Glcp-(1→. Meanwhile, we prepared aluminium hydroxide nanoparticles (Al NPs) with a nanometer-scale size and thin stick-like shape. Being an immunostimulant, the CYP was then loaded onto the Al NPs to obtain a novel adjuvant delivery system (CYP-Al NPs) that enhances the immunostimulatory activity of CYP. Our findings showed that the CYP-Al NPs facilitated macrophages activation and promoted the antigen uptake by macrophages. The in vivo experiment showed that the CYP-Al NPs, as the adjuvant to ovalbumin, promoted the activation of dendritic cells and germinal center B cells in draining lymph nodes, induced a durable and strong antibody response, especially the Th1-type IgG2a antibody response, and improved the cytotoxic T lymphocytes response. These results demonstrated that the CYP-Al NPs could generate robust humoral and cellular responses, and has the great potential to serve as an adjuvant delivery system.

Sulfated Chinese yam polysaccharide exert anti-inflammatory potential via MAPK/NF-κB signaling pathways in a co-culture system and LPS-induced acute inflammatory mice model.

Our previous study has demonstrated that sulfated Chinese yam polysaccharide (SCYP) can improve immunomodulatory activity in Raw 264.7 cells. However, its anti-inflammatory is little known. In this study, the anti-inflammatory effects of SCYP were systematically investigated via the Lipopolysaccharides (LPS)-induced Raw264.7 cell model, Caco-2/Raw264.7 co-culture system, and acute inflammation mice model. The results suggested SCYP promoted the cell proliferation and have no toxicity in Raw264.7 and Caco-2 cells at the concentration of 200µg/mL. Moreover, when treated with SCYP, the production of pro-inflammatory cytokines (interleukin [IL]-1β, IL-6, and tumor necrosis factor-α) reduced significantly in Raw264.7 via the MAPK/NF-κB pathway. In the Caco-2/Raw264.7 co-cultured system, SCYP could regulate inflammation reaction by improving intestinal barrier, which might prevent systemic inflammation. Further, systemic inflammation was alleviated by SCYP in LPS-induced acute inflammation mice through MAPK/NF-κB pathway. PRACTICAL APPLICATION: These results supported that SCYP may be used as an anti-inflammation agent in the functional food field.

Whole Plant Extracts for Neurocognitive Disorders: A Narrative Review of Neuropsychological and Preclinical Studies.

The incidence of neurodegenerative disorders like Alzheimer's or Parkinson's Disease, characterized by a progressive cognitive decline, is rising worldwide. Despite the considerable efforts to unveil the neuropsychological bases of these diseases, there is still an unmet medical need for effective therapies against cognitive deficits. In recent years, increasing laboratory evidence indicates the potential of phytotherapy as an integrative aid to improve cognitive functions. In this review, we describe the data of plant whole extracts or single compounds' efficacy on validated preclinical models and neuropsychological tests, aiming to correlate brain mechanisms underlying rodent behavioral responses to human findings. After a search of the literature, the overview was limited to the following plants: Dioscorea batatas, Ginkgo biloba, Melissa officinalis, Nigella sativa, Olea europaea, Panax ginseng, Punica granatum, and Vitis vinifera. Results showed significant improvements in different cognitive functions, such as learning and memory or visuospatial abilities, in both humans and rodents. However, despite promising laboratory evidence, clinical translation has been dampened by a limited pharmacological characterization of the single bioactive components of the herbal products. Depicting the contribution of the single phytochemicals to the phytocomplex's pharmacological efficacy could enable the comprehension of their potential synergistic activity, leading to phytotherapy inclusion in the existing therapeutic package against cognitive decline.

Shenqi Pill alleviates acetaminophen-induced liver injury: a comprehensive strategy of network pharmacology and spectrum-effect relationship reveals mechanisms and active components

BackgroundAcetaminophen (APAP), commonly used for its antipyretic and analgesic properties, can cause severe liver injury or even acute liver failure when overdosed. However, the options for treating APAP-induced liver toxicity are limited. Shenqi Pill (SQP), a traditional Chinese herbal formula, has shown effectiveness in treating various liver ailments. SQP consists of cinnamon, aconite, rehmannia, cornus, peony bark, Chinese yam, poria, and alisma in a ratio of 1:1:8:4:3:4:3:3. However, the mechanisms and active components of SQP that counteract drug-induced liver injury (DILI) are not well understood. PurposeThis study aimed to explore the protective effects of SQP against APAP-induced liver injury in both laboratory and animal settings. It seeks to identify the active components and potential mechanisms by which SQP targets mitochondria to alleviate liver damage. MethodsA mouse model with APAP-induced liver injury was established to assess SQP's therapeutic impact. This study then analyzed the components of SQP using UPLC-Q-TOF-MS in both in vivo and in vitro environments. Network pharmacology and the GEO database helped predict potential pathways and targets. Potential active components were identified through spectrum-effect relationship analysis and validated their efficacy using Seahorse assays and molecular docking. ResultsTreatment with SQP significantly reduced liver dysfunction, tissue damage, lipid metabolic disruptions, and inflammation caused by APAP in mice. In cellular tests, SQP-treated serum notably enhanced mitochondrial function, maintained membrane potential, decreased ROS levels, and prevented mitochondrial permeability transition pore opening. Biochemically, SQP reversed the suppression of p-AMPK, p-ACC, CPT1, and ACADM expression caused by APAP overdose. This study identified 97 in vitro and 24 in vivo components of SQP, with eight showing significant mitochondrial benefits. Molecular docking studies suggest that fuziline and paeoniflorin could activate AMPK. ConclusionSQP effectively mitigates APAP-induced liver injury by enhancing mitochondrial function via the AMPK-ACC-CPT1-ACADM pathway. Moreover, this study introduces a novel strategy for analyzing the relationship between the chemical and pharmacological properties of drug-containing serum, successfully identifying compounds with mitochondrial activity. Fuziline and paeoniflorin, in particular, emerge as promising mitochondrial protectants and warrant further investigation. This research underpins the development of innovative treatments for DILI using SQP and its components.

The metabolic profiling of Chinese yam fermented by Saccharomyces boulardii and the biological activities of its ethanol extract in vitro

Chinese yam (Dioscorea opposita Thunb.), as one of the medicinal and edible homologous plants, is rich in various nutrients and functional factors. In this study, Chinese yam fermented by Saccharomyces boulardii was performed to investigate its bioactive components and metabolic profile. And then, the main bioactive components and biological activities of fermented Chinese yam ethanol extract (FCYE) were evaluated. Results showed that there were 49 up-regulated metabolites and 52 down-regulated metabolites in fermented Chinese yam compared to unfermented Chinese yam. Besides, corresponding metabolic pathways analysis initially revealed that the distribution of bioactive substances was concentrated on alcohol-soluble small molecular substances. Ulteriorly, the total polyphenol content and the total flavonoid content in FCYE were significantly increased, and the corresponding antioxidant and immunomodulatory activities in vitro were also significantly enhanced. Our study provided a new reference for the comprehensive utilization of Chinese yam and laid a theoretical foundation for the development and application of natural probiotic-fermented products.

Investigating the Discoloration of Leaves of Dioscorea polystachya Using Developed Atomic Absorption Spectrometry Methods for Manganese and Molybdenum.

The Chinese yam (Dioscorea polystachya, DP) is promising for the food and pharmaceutical industries due to its nutritional value and pharmaceutical potential. Its proper cultivation is therefore of interest. An insufficient supply of minerals necessary for plant growth can be manifested by discoloration of the leaves. In our earlier study, magnesium deficiency was excluded as a cause. As a follow-up, this work focused on manganese and molybdenum. To quantify both minerals in leaf extracts of DP, analytical methods based on atomic absorption spectrometry (AAS) using the graphite furnace sub-technique were devised. The development revealed that the quantification of manganese works best without using any of the investigated modifiers. The optimized pyrolysis and atomization temperatures were 1300 °C and 1800 °C, respectively. For the analysis of molybdenum, calcium proved to be advantageous as a modifier. The optimum temperatures were 1900 °C and 2800 °C, respectively. Both methods showed satisfactory linearity for analysis. Thus, they were applied to quantify extracts from normal and discolored leaves of DP concerning the two minerals. It was found that discolored leaves had higher manganese levels and a lower molybdenum content. With these results, a potential explanation for the discoloration could be found.

Diosgenin-rich Yam (rhizome of Dioscorea batatas) extract ameliorates cognitive functions and plasma biomarkers for mild cognitive impairment and mild Alzheimer's disease: A randomized controlled trial

IntroductionIn Alzheimer's disease (AD), neural circuit disconnection primarily causes memory dysfunction, which leads to the hypothesis that repairing neural networks may be an appropriate treatment strategy for AD. We previously found that diosgenin stimulated neurite regeneration and synapse formation in AD model mice, and diosgenin-rich Yam extract enhanced cognitive function in healthy people and normal mice. In this study, we investigated the efficacy and safety of Yam extract in patients with mild cognitive impairment (MCI) and mild AD. MethodsPatients were administered either diosgenin-rich Yam extract or placebo, respectively, for 24 weeks. The primary outcome was cognitive function, which was evaluated using the Mini Mental State Examination Japanese version (MMSE-J), Alzheimer's Disease Assessment Scale-Cognition (ADAS-Cog), and verbal fluency test; the secondary outcomes were plasma biomarker levels [neurofilament light chain (NfL); axonal marker, glial fibrillary acidic protein levels; reactive astrocyte marker, and the Aβ42/40 ratio; marker of brain Aβ]. ResultsDiosgenin-rich Yam extract improved the ADAS-Cog Praxis domain score and plasma NfL (12 to 24 weeks) in all patients. The number of patients with improved/maintained ADAS-Cog total, Praxis or Memory scores was high in the Yam extract group, but not in placebo group. Divided by severity of pathology, diosgenin-rich Yam extract also improved the total and Memory domain in ADAS-Cog, and plasma NfL levels in patients with MCI. In the Yam extract group, improvement of MMSE-J was related to plasma Aβ42/40 increase, and improvement of plasma NfL was related to better MMSE-J. ConclusionTreatment with diosgenin-rich Yam extract for 24 weeks resulted in modest cognitive improvement and a decrease in plasma NfL levels, which may suggest axonal protection in the brain.

First report of basal stem rot caused by three Fusarium species on Chinese yam in China.

The cultivated variety of Chinese yam (Dioscorea polystachya Turcz. cv. Tiegun) is an economically important plant, capable of producing tubers that are used as food and traditional Chinese medicine. The basal stem rot was found on approximately 65% of yam (tuber expansion stage) in a total of 10 ha field in Wuzhi, Wen, and Hua counties, Henan, China (Sep 2021). Dark brown fusiform lesions initially occurred at the stems basal, irregularly extending to join together and leading to loop-stem necrotic indentation. Three diseased samples from Wuzhi county were collected, cut into 5 × 5 mm pieces, surface sterilized in 75% ethanol (30 s) and 1% NaClO (1 min), washed in sterile water 3 times, and placed on PDA in the dark for 3 days at 28℃. A total of 44 isolates forming three groups of Fusarium colonies were obtained using monosporic isolation, of which 19, 8, and 17 isolates were identified as F. oxysporum, F. solani, and F. proliferatum based on colony morphology, respectively. Typical isolates SYJJ6, 9, and 10 for each group were further studied. The SYJJ6 colonies showed gray white abundant fluffy aerial mycelium with rough edges, formation of ellipsoid, unicellular microconidia without septa, 5.6 to 13.4 × 2.4 to 4.7 μm (n = 50), and sickle-shaped, slightly curved macroconidia with 2 to 4 septa, 14.0 to 23.9 × 3.4 to 5.1 μm (n = 50). Isolate SYJJ9 produced flocculent white colonies, grew in a circular pattern with a sharp edge, forming oval or oblong microconidia with zero or one septum, 11.2 to 18.8 × 3.4 to 6.2 μm (n = 50), and slightly curved macroconidia with 2 to 3 septa, 27.6 to 44.0 × 3.9 to 7.4 μm (n = 50). SYJJ10 produced whitish or pinkish white colonies with fluffy aerial mycelium and a red pigmentation, produced renal or oval microconidia with no septa, 5.1 to 11.8 × 1.8 to 4.2 μm (n = 50), and falcate, slightly curved macroconidia with 3 to 4 septa, 16.1 to 30.2 × 3.1 to 5.9 μm (n = 50). Additionally, TUB, EF-1α, and RPB2 genes were amplified with primers BT2a/BT2b, EF1/EF2, and 5f2/-7cr, respectively (Glass and Donaldson 1995; O'Donnell et al. 1998, 2010). BLASTn analysis on SYJJ6 (OR047663, OR047666, OR047669), SYJJ9 (OR047665, OR047667, OR047670), and SYJJ10 (OR047664, OR047668, OR047671) gene sequences were over 99% identical to those of F. oxysporum (100%, MK432917; 100%, MN417196; 99.61%, MN457531), F. solani (100%, MF662662; 100%, MN223440; 99.80%, CP104055), and F. proliferatum (100%, ON557521; 100%, ON458137; 99.90%, LT841266), respectively. Pathogenicity tests of three isolates were separately performed on 60-day-old yam seedlings. The basal stems were wounded using needle, and the wounds were wrapped with cotton balls soaked with conidial suspension (1 mL, 3×106 conidia/mL) or water (control). Each isolate treated three plants and repeated three times. All plants were grown at 28℃ under a 16/8-h light/dark cycle. Typical symptoms emerged on basal stems at 16, 13, and 17 days after inoculation with the conidia of isolates SYJJ6, 9, and 10, while the control basal stems appeared healthy. The re-isolated fungi were identical to the original three isolates. Fusarium species (F. oxysporum, F. commune, F. humuli, etc.)were previously reported to cause wilt or stem rot on different D. polystachya cultivars (Fang et al. 2020; Li et al. 2023; Zhao et al. 2013), or basal stem rot on Panax ginseng (Ma et al. 2020). This is the first report of Chinese yam basal stem rot caused by Fusarium species, which threatens the production of Chinese yam 'Tiegun' and should be further studied.

Effects of cold plasma pretreatment before different drying process on the structural and functional properties of starch in Chinese yam

This article compared the effects of hot air drying (HAD), infrared drying (IRD), and cold plasma (CP) as a pretreatment on the structure, quality, and digestive characteristics of starch extracted from yam. As the most commonly used drying method, HAD was used as a control. SEM and CLSM images showed that all treatments preserve the integrity of the yam starch. CP caused some cracks and breaks in the starch granules. IRD did not destroy the crystal structure of starch molecules, but made the spiral structure tighter and increased short-range orderliness. However, CP led to the depolymerization and dispersion of starch molecular chains, resulting in a decrease in average molecular weight and relative crystallinity. These molecular conformation changes caused by different processes led to differences in solubility, swelling power, pasting parameters, digestion characteristics, and functional characteristics. This study provided an important basis for the reasonable drying preparation and utilization of yam starch.

Effects of multiphase microwave drying on the microstructure of Chinese yam: A study based on X-ray micro-computed tomography technology

To address the issues of long drying time and high equipment costs present in freeze drying and freeze drying-microwave vacuum combined drying techniques, as well as to obtain higher-quality dried products, multiphase microwave drying (MMD) has been proposed. This study investigated the effects of MMD at different transition point moisture content levels (0.36, 0.59, and 0.79 g/g d.b.) on the microstructure and texture of dried Chinese yam. Using freeze drying (FD), microwave freeze drying (MFD), and microwave vacuum drying (MVD) as controls, X-ray micro-computed tomography (micro-CT) visualized and quantified Chinese yam’s structure across drying methods. The results indicated that as the transition point moisture content increased, the porosity and connected pore area and volume decreased, while non-connected pore area and volume increased. Chinese yam samples obtained from MMD scheme I (transition point moisture content of 0.36 g/g d.b.) exhibited a uniform and porous structure with a high total porosity (48.19 ± 0.32%), similar in hardness and shrinkage to freeze-dried yams, preserving microstructural integrity. MMD reduced drying time and maintained the quality of dried Chinese yam compared to FD, MVD, and MFD, highlighting its potential as a cost-effective method for producing premium dried Chinese yam products.

Protection effect of Dioscoreae Rhizoma against ethanol-induced gastric injury in vitro and in vivo: A phytochemical and pharmacological study

Ethnopharmacological relevanceDioscoreae Rhizoma, a kind of Chinese yam, is a medicinal and edible plant used in China for strengthening the spleen and stomach. However, there is a lack of modern pharmacology studies regarding its anti-gastric injury activity. Aim of the studyThis study aimed to investigate the phytochemical composition of Chinese yam aqueous extract (CYW) and evaluate its gastroprotective effects against ethanol-induced gastric injury in vitro and in vivo. Materials and methodsThe active components of CYW were identified using HPLC-QTOF-MS/MS in combination with the GNPS molecular networking and network pharmacology. In vitro studies were performed in the RAW264.7/GES-1 cell coculture system. In vivo study, mice were treated with CYW (0.31, 0.63, and 3.14 g/kg BW, orally) for 14 days, followed by a single oral dose of ethanol (10 mL/kg BW) to induce gastric injury. The biochemical, inflammation and oxidative stress markers were analyzed using commercial kits. Histopathology was used to assess the degree of gastric injury. Gene and protein expressions were studied using RT-qPCR and western blotting, respectively. ResultsCYW significantly restored the levels of SOD, GPx and CAT, and reduced the MDA content. Further analyses showed that CYW significantly alleviated the gastric oxidative stress by inhibiting the inflammation via decreasing p-NF-κB and p-IκB-α expression levels and inhibiting the generation of IL-6, TNF-α, and IL-1β. At the same time, the fraction remarkably upregulated Bcl-2, downregulated Bax and increased growth factor secretion, thereby prevented gastric mucous cell. Besides, The combination of HPLC-QTOF-MS/MS, GNPS molecular networking analysis, and network pharmacology demonstrated that linoleic acid, 3-acetyl-11-keto-beta-boswellic acid, adenosine, aminocaproic acid, tyramine, DL-tryptophan, cycloleucine, lactulose, melibiose, alpha-beta-trehalose, and sucrose would be the main active compounds of CYW against ethanol-induced gastric injury. ConclusionThis study showed that CYW is potentially rich source of anti-oxidant and anti-inflammatory bioactive compounds. It showed efficacy against ethanol-induced gastric injury by inhibiting inflammation, oxidative stress, and apoptosis in the stomach. The results of the current work indicate that Dioscoreae Rhizoma could be utilized as a type of natural resource for production of new medicine and functional foods to prevent and/or ameliorate ethanol-induced gastric injury.

An evaluation on the shrinkage deformation characteristics of Chinese yam during multiphase microwave drying based on digital image processing

The deformation characteristics of Chinese yam during multiphase microwave drying (MMD) was evaluated by image processing, and the effects of MMD on the drying characteristics, physical properties, shrinkage behavior, and microstructure of the samples were also investigated. The drying time was significantly reduced by increasing microwave power density. Compared with Scheme I, the time of Scheme V was shortened by 22.22%. The moisture content at the transition point from sublimation to evaporation drying stages (TPS-E) significantly affected the shrinkage of the samples. In Scheme I, the lowest moisture content at TPS-E of 0.354 g. g−1 was found, and the dried products with the shrinkage ratio and bulk density closest to those of FD. The deformation of Chinese yam mainly appeared in the evaporation drying stage. At this stage, the rate of change in cross-sectional area of dried samples ranged from 9.74% to 26.76% for Schemes II to Scheme V, compared to 2.03% for Scheme I. Similarly, the shrinkage ratio of the dried samples in Schemes II, III, IV, and V increased from 16.82% to 21.12% at TPS-E to 29.23% to 51.28% at the end of drying, respectively. Additionally, the shrinkage caused by the pores collapse of the samples because of the high moisture content at TPS-E (Scheme III, IV, and V) during the evaporation drying stage resulted in increases of bulk density. The present study can provide valuable insights for rational control of shrinkage and deformation of fruits and vegetables in MMD. Industrial relevanceChinese yam is a widely used food and medicinal resource in China due to its rich nutritional and medicinal values. Since the moisture content of Chinese yam can reach as high as 70–80%, drying serves as an effective method to broaden its application. However, shrinkage and deformation of materials during drying are common forms of appearance deterioration that can directly impact consumer acceptability. MMD has proven to be a promising drying technology. Nevertheless, improper drying parameter settings may lead to a deterioration of the appearance quality of MMD products. Therefore, comprehending the information of shrinkage and deformation of Chinese yam during MMD and effectively regulating these processes is essential. Mastering these aspects is critical for enhancing the economic value and consumer acceptance of dried Chinese yam products.