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 alcoholsoluble 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.

Chinese yam(Dioscorea opposita Thunb.) Notillage Ecological Cultivation Technique

For traditional cultivation of Chinese yam, it is necessary to dig a deep trench duringsowing and harvest, wasting labor and time, and Chinese yam requires good quality of cultivated land, causing serious impact on the development of yam industry due to the competition with food production. Yam no-tillage ecological cul- ture techniques, combined with advantage of yam directional tuberization, could en- able the cultivation of yam inlow-production field, barren hills and sloping field, forest land and other non-staple food land and thus could promote farmers＇ income as well as improving the ecological environment.

Identification of Polysaccharides from Chinese Yam(Dioscoreae opposite “Qi”) by Infrared Spectroscopy

In this study, the structure of polysaccharides from Chinese yam （Dioscoreae opposite ＂Qi＂） was analyzed and identified by infrared spectroscopy within an infrared spectral range of 400-4 000 cm^-1, Characteristic absorption peaks were observed at 840 cm^-1 （α-glucosidic bond）, 759.21 cm^-1 （xylose）, 830.87 cm^-1 （rhamnose）, 812.81 cm^-1, 876.60 cm^-1 （mannose） and 842.64 cm^-1 （arabinose） in infrared spectra of polysaccharides from D. opposite ＂Qi＂, indicating that D. opposite ＂Qi＂ polysaccharides exist mainly in the form of α-glucosidic bonds, including xylose, rhamnose, mannose and arabinose. The experimental results could provide the basis for quantitative analysis, development and application of polysaccharides from D. opposite ＂Qi＂.

Stewed Chinese Yam, Gorgon Fruits with Duck

Draw the duck, clean, and scald, together with the lean pork. Remove and drain. Rinse in cold water.Pour away the hot water from the pot,

Chinese yam yield is affected by soil nutrient levels and interactions among N, P, and K fertilizers

Objective: The current fertilization methods for Chinese yam are uneconomic and unfriend to environment. A rational one is very important to achieve desired balance of high yield of Chinese yam, economic and friend to environment. Here, we studied the effects of nitrogen(N), phosphorus(P), and potassium(K) fertilizers on the yield of ’Qinfeng’ Chinese yam in shallow-groove directional cultivation.Methods: The experiments were conducted in Dehua County, Fujian Province, China using a "3414" optimal design. Overall, three fertilizer factors(N, P, and K) were evaluated at the following four levels: 0, no fertilizer;1, 0.5-fold the typical rate;2, typical fertilization rate;and 3, 1.5-fold the typical rate. There were 14 different fertilization treatments.Results: Treatment 6(N2P2K2) produced the longest(75.6 cm) and thickest tubers(4.9 cm) with the highest tuber fresh weight(1311.9 g) and yield(41 015.9 kg/hm2), whereas, treatment 1 produced the shortest(65.6 cm) and thinnest tubers(3.9 cm) with the lowest fresh weight(953.4 g) and yield(28 532.8 kg/hm2) among the 14 fertilizer combinations. The experimental data could be fitted to single-variable quadratic and binary quadratic models but not to a ternary quadratic polynomial model. Appropriate N, P, and K fertilizer application rates increased Chinese yam yield. However, excessive fertilization lowered the yield. Chinese yam yield was significantly and strongly correlated with the amounts of N, P, and K fertilizer applied.Conclusion: Based on the single variable quadratic and binary quadratic models, we propose that the quantities of N, P, and K fertilizer used to grow 1 hm^(2)’Qinfeng’ Chinese yam should be 360–388.3,90–100.95, and 416.3–675 kg, respectively.

Effects of different pretreatments on the pore structure of Chinese yam during microwave freeze drying

In order to explore the effects of different pretreatments on the pore structure of Chinese yam during Microwave Freeze Drying(MFD),the samples were treated by typical drying pretreatments including osmosis,blanching and ultrasound,and compared with the untreated samples.The results showed that the pretreatment had significant impacts on the porosity of MFD Chinese yam.Ultrasonic pretreatment could obtain the highest open porosity,and the internal pore network structure of the material showed a uniform sponge shape.The shape of pores obtained by blanching pretreatment was the most irregular.The pore network structure obtained by different pretreatments could result in various product texture and rehydration,which implied that pretreatment methods should be carefully selected according to actual requirements.All these pretreatments could improve the open porosity of MFD Chinese yam,which result in a better rehydration capability.Among them,ultrasonic treatment is worth further investigating.