Fermentation of the succulent bamboo shoots of Bambusa balcooa Roxb. resulted in an enrichment of phytosterols from 0.12% to 0.62% dry weight as compared to that of the fresh unfermented samples. The bacterial strains...Fermentation of the succulent bamboo shoots of Bambusa balcooa Roxb. resulted in an enrichment of phytosterols from 0.12% to 0.62% dry weight as compared to that of the fresh unfermented samples. The bacterial strains responsible for higher accumulation of phytosterols during fermentation of the bamboo shoots have been isolated and further extraction and purification of the crude phytosterols (isolated from the fermented samples) were done by TLC, UV, NMR, IR and Mass spectral analysis. The isolated phytosterols (β-sitos-terols) were then subjected to microbial transformation which yielded a considerable amount of androsta-1, 4-diene-3,17-dione (ADD) in the incubation mixture in presence of metabolic inhibitors (α, α＇-dipyridyl and sodium arsenate).展开更多
Giant reed is a suitable pioneer plant for metal-contaminated soil phytoremediation,however,it is imperative to dispose the metal-contaminated biomass after harvesting.The liquefaction of metal-contaminated giant reed...Giant reed is a suitable pioneer plant for metal-contaminated soil phytoremediation,however,it is imperative to dispose the metal-contaminated biomass after harvesting.The liquefaction of metal-contaminated giant reed biomass in ethylene glycol system with sulfuric acid as catalyst for the precursors of polyurethane compounds was studied.The results show that giant reed biomass from metal-contaminated soil is potentially liquefied and significantly affected by solvent/solid ratio,liquefaction temperature and liquefaction time （P〈0.05）.The liquefaction rate of biomass in acidified ethylene glycol system can reach 85.2% with optimized conditions of 60 min,170 ℃,3% sulfuric acid and solvent/biomass ratio of 5：1.The hydroxyl value of liquefied products is of 481 mg KOH/g while reactive hydroxyl groups of them are abundant,which is promised as potential precursors for polyurethane compounds.The solvent liquefaction is a potential method to dispose the metal-contaminated biomass,however,the containing-metal liquefied products should be studied deeply in order to get the suitable precursors in future.展开更多
Forest thinning and ground cover plant management play crucial roles in habitat enhancement,yet their effects on soil microbiota remain poorly understood.This study examines their impact on soil properties and bacteri...Forest thinning and ground cover plant management play crucial roles in habitat enhancement,yet their effects on soil microbiota remain poorly understood.This study examines their impact on soil properties and bacterial communities in artifcial spruce forests(Picea asperata)within China’s Huangtuliang ecological corridor,a crucial habitat for giant pandas.Thinning signifcantly alters soil pH and total phosphorus(TP)levels,with minimal changes observed in total nitrogen(TN),microbial biomass carbon(MBC)and nitrogen(MBN).The combined effect of thinning and ground cover presence increases soil organic carbon(SOC)to 65.47 g/kg,contrasting with its absence.Thinning enhances the abundance of Proteobacteria,Acidobacteria and Chlorofexi while reducing Actinobacteria.Conversely,ground cover removal decreases Proteobacteria and Bacteroidetes but increases Chlorofexi,Verrucomicrobia and Rokubacteria.These changes lead to reduced bacterial community diversity,as indicated by a lower Shannon diversity index and distinct community composition differences demonstrated through beta-diversity analysis.Soil pH,TP and MBN are crucial in maintaining bacterial community structure,with pH and TP exhibiting the strongest correlations.Network analysis confrms the signifcant infuence of TP and pH on bacterial genera across various phyla.This study reveals the role of stochastic processes in highelevation,low-temperature ecological corridors(R^(2)=0.817),with thinning’s impact varying depending on the ground cover presence,thus enhancing effects post-removal by reducing dispersal limitation(migration rate,m=0.96).These fndings highlight the ecological implications of habitat management in sensitive ecosystems and advance our understanding of microbial dynamics in critical habitats.展开更多
文摘Fermentation of the succulent bamboo shoots of Bambusa balcooa Roxb. resulted in an enrichment of phytosterols from 0.12% to 0.62% dry weight as compared to that of the fresh unfermented samples. The bacterial strains responsible for higher accumulation of phytosterols during fermentation of the bamboo shoots have been isolated and further extraction and purification of the crude phytosterols (isolated from the fermented samples) were done by TLC, UV, NMR, IR and Mass spectral analysis. The isolated phytosterols (β-sitos-terols) were then subjected to microbial transformation which yielded a considerable amount of androsta-1, 4-diene-3,17-dione (ADD) in the incubation mixture in presence of metabolic inhibitors (α, α＇-dipyridyl and sodium arsenate).
基金Project(41271330)supported by the National Natural Science Foundation of ChinaProject(2012BAC09B04)supported by the National Key Technology Research and Development Program of the Ministry of Science and Technology of ChinaProject(2012FJ1010)supported by the Science and Technology Major Program of Hunan Province,China
文摘Giant reed is a suitable pioneer plant for metal-contaminated soil phytoremediation,however,it is imperative to dispose the metal-contaminated biomass after harvesting.The liquefaction of metal-contaminated giant reed biomass in ethylene glycol system with sulfuric acid as catalyst for the precursors of polyurethane compounds was studied.The results show that giant reed biomass from metal-contaminated soil is potentially liquefied and significantly affected by solvent/solid ratio,liquefaction temperature and liquefaction time （P〈0.05）.The liquefaction rate of biomass in acidified ethylene glycol system can reach 85.2% with optimized conditions of 60 min,170 ℃,3% sulfuric acid and solvent/biomass ratio of 5：1.The hydroxyl value of liquefied products is of 481 mg KOH/g while reactive hydroxyl groups of them are abundant,which is promised as potential precursors for polyurethane compounds.The solvent liquefaction is a potential method to dispose the metal-contaminated biomass,however,the containing-metal liquefied products should be studied deeply in order to get the suitable precursors in future.
基金supported by the Sichuan Science and Technology Program,China(Grant No.2023YFS0372).
文摘Forest thinning and ground cover plant management play crucial roles in habitat enhancement,yet their effects on soil microbiota remain poorly understood.This study examines their impact on soil properties and bacterial communities in artifcial spruce forests(Picea asperata)within China’s Huangtuliang ecological corridor,a crucial habitat for giant pandas.Thinning signifcantly alters soil pH and total phosphorus(TP)levels,with minimal changes observed in total nitrogen(TN),microbial biomass carbon(MBC)and nitrogen(MBN).The combined effect of thinning and ground cover presence increases soil organic carbon(SOC)to 65.47 g/kg,contrasting with its absence.Thinning enhances the abundance of Proteobacteria,Acidobacteria and Chlorofexi while reducing Actinobacteria.Conversely,ground cover removal decreases Proteobacteria and Bacteroidetes but increases Chlorofexi,Verrucomicrobia and Rokubacteria.These changes lead to reduced bacterial community diversity,as indicated by a lower Shannon diversity index and distinct community composition differences demonstrated through beta-diversity analysis.Soil pH,TP and MBN are crucial in maintaining bacterial community structure,with pH and TP exhibiting the strongest correlations.Network analysis confrms the signifcant infuence of TP and pH on bacterial genera across various phyla.This study reveals the role of stochastic processes in highelevation,low-temperature ecological corridors(R^(2)=0.817),with thinning’s impact varying depending on the ground cover presence,thus enhancing effects post-removal by reducing dispersal limitation(migration rate,m=0.96).These fndings highlight the ecological implications of habitat management in sensitive ecosystems and advance our understanding of microbial dynamics in critical habitats.
