Two oligosaccharide fractions(MLO 2-1 and 2-2)were purified from enzymatic hydrolysate of mulberry leaf polysaccharide.The results of simulated digestion showed that MLO 2-2 was a digestible oligosaccharide,which coul...Two oligosaccharide fractions(MLO 2-1 and 2-2)were purified from enzymatic hydrolysate of mulberry leaf polysaccharide.The results of simulated digestion showed that MLO 2-2 was a digestible oligosaccharide,which could be degraded by human digestive juice;while MLO 2-1 possessed the non-digestible property in the upper gastrointestinal tract and performed the function by regulating the gut microbiota.Hence,MLO 2-1 was selected for the further analysis.The structure of MLO 2-1 was elucidated as follow:α-T-Glcp-(1→3)-β-Glcp-(1→5)-α-Araf-(1→5)-α-Araf-1→5)-α-Araf-(1→3)-α-(2-OAc)-Glcp-1.The in vitro fecal fermentation results showed that MLO 2-1 could modulate the composition of gut microbiota.Meanwhile,MLO 2-1 was effectively metabolized by fecal bacteria to produce lactate and short chain fatty acids,especially acetate and butyrate.The specific metabolic pathways of MLO 2-1 by gut microbiota were further illuminated.Gut microbiota analysis revealed that MLO 2-1 selectively promoted the growth of Ligilactobacillus murinus,a commensal bacterium presented a reduced level in T2DM mice.Animal experiments indicated that MLO 2-1 and L.murinus exhibited hypoglycemic activities.These results demonstrated that MLO 2-1 might alleviate T2DM by selectively accelerating the proliferation of L.murinus.展开更多
An isotope dilution ultra-performance liquid chromatography-triple quadrupole mass spectrometry method was developed to simultaneously detect two typical kinds ofα,β-unsaturated aldehydes,namely 4-hydroxy-2-hexenal(...An isotope dilution ultra-performance liquid chromatography-triple quadrupole mass spectrometry method was developed to simultaneously detect two typical kinds ofα,β-unsaturated aldehydes,namely 4-hydroxy-2-hexenal(4-HHE)and 4-hydroxy-2-nonenal(4-HNE),in foods.The proposed method exhibited a linear range of 10-1000 ng/mL with a limit of detection of 0.1-2.0 ng/g and a limit of quantification of 0.3-5.0 ng/g.The recovery rates of these typical toxic aldehydes(i.e.,4-HHE,4-HNE)and their d3-labeled analogues were 91.54%-105.12%with a low matrix effect.Furthermore,this proposed method was successfully applied to a real frying system and a simulated digestion system,wherein the contents of 4-HHE and 4-HNE were determined for both.Overall,the obtained results provide strong support for further research into the production of 4-HHE and 4-HNE resulting from foods during oil digestion and frying.展开更多
Juice drinks are an important commercialization alternative for lychee, a tropical and subtropical fruit. Although the lychee juice content is important when assessing the quality of a drink, there are no published me...Juice drinks are an important commercialization alternative for lychee, a tropical and subtropical fruit. Although the lychee juice content is important when assessing the quality of a drink, there are no published methods to determine it, particularly simple ones for the routine inspection of juice drinks. Lychee juice drinks contain ingredients with buffering capacity including proteins and ions such as phosphate, citrate, lactate, carbonate, acetate and propionate. The relationship between their buffering capacity and lychee juice content was studied. Citric acid was added to pure lychee dilutions in distilled water containing 100%, 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20% and 10% lychee juice. The pH of the dilutions was measured to obtain a linear model for the molar H+ concentration as a function of the added citric acid (g/L) amount LC = (BC-494.2)/12,031, where LC was the lychee juice content and BC was defined as the juice buffering coefficient.展开更多
基金the Key Research and Development Program of Yunnan Province(No.202202AE090023)Key Research and Development Program of Guangdong Province(No.2022B0202040002+8 种基金2022B0202050001)the Key Laboratory of Green Processing and Intelligent Manufacturing of Lingnan Specialty Food,Ministry of Agriculturethe Heyuan Branch,Guangdong Laboratory for Lingnan Modern Agriculture Project(No.DT20220026)Talent Introduction Program of Guangdong Academy of Agricultural Sciences(No.R2022YJ-YB3004)the Basic and Applied Basic Research Project of Guangdong Province(No.2022A15151102272023A1515012386)the Science and Technology Planning Project of Guangzhou(No.2023A04J0828)the Guangdong Provincial Special Fund for Modern Agriculture Industry Technology Innovation Teams(No.202109TD)the Special Fund Project for Teachers’Scientific and Technological Achievements Transformation in Shunde Innovation Park,National University Science Park,South China University of Technology(No.KJYS2021KZ05)for their financial support。
文摘Two oligosaccharide fractions(MLO 2-1 and 2-2)were purified from enzymatic hydrolysate of mulberry leaf polysaccharide.The results of simulated digestion showed that MLO 2-2 was a digestible oligosaccharide,which could be degraded by human digestive juice;while MLO 2-1 possessed the non-digestible property in the upper gastrointestinal tract and performed the function by regulating the gut microbiota.Hence,MLO 2-1 was selected for the further analysis.The structure of MLO 2-1 was elucidated as follow:α-T-Glcp-(1→3)-β-Glcp-(1→5)-α-Araf-(1→5)-α-Araf-1→5)-α-Araf-(1→3)-α-(2-OAc)-Glcp-1.The in vitro fecal fermentation results showed that MLO 2-1 could modulate the composition of gut microbiota.Meanwhile,MLO 2-1 was effectively metabolized by fecal bacteria to produce lactate and short chain fatty acids,especially acetate and butyrate.The specific metabolic pathways of MLO 2-1 by gut microbiota were further illuminated.Gut microbiota analysis revealed that MLO 2-1 selectively promoted the growth of Ligilactobacillus murinus,a commensal bacterium presented a reduced level in T2DM mice.Animal experiments indicated that MLO 2-1 and L.murinus exhibited hypoglycemic activities.These results demonstrated that MLO 2-1 might alleviate T2DM by selectively accelerating the proliferation of L.murinus.
基金This work was supported by the National Natural Science Fund of China(32001622)the Guangdong Basic and Applied Research Foundation(2021A1515011060)+1 种基金the Fundamental and Applied Basic Research Fund for Young Scholars of Guangdong Province(2019A1515110823)the Guangdong Key Laboratory of Science and Technology of Lingnan Specialty Foods(2021B1212040013).
文摘An isotope dilution ultra-performance liquid chromatography-triple quadrupole mass spectrometry method was developed to simultaneously detect two typical kinds ofα,β-unsaturated aldehydes,namely 4-hydroxy-2-hexenal(4-HHE)and 4-hydroxy-2-nonenal(4-HNE),in foods.The proposed method exhibited a linear range of 10-1000 ng/mL with a limit of detection of 0.1-2.0 ng/g and a limit of quantification of 0.3-5.0 ng/g.The recovery rates of these typical toxic aldehydes(i.e.,4-HHE,4-HNE)and their d3-labeled analogues were 91.54%-105.12%with a low matrix effect.Furthermore,this proposed method was successfully applied to a real frying system and a simulated digestion system,wherein the contents of 4-HHE and 4-HNE were determined for both.Overall,the obtained results provide strong support for further research into the production of 4-HHE and 4-HNE resulting from foods during oil digestion and frying.
文摘Juice drinks are an important commercialization alternative for lychee, a tropical and subtropical fruit. Although the lychee juice content is important when assessing the quality of a drink, there are no published methods to determine it, particularly simple ones for the routine inspection of juice drinks. Lychee juice drinks contain ingredients with buffering capacity including proteins and ions such as phosphate, citrate, lactate, carbonate, acetate and propionate. The relationship between their buffering capacity and lychee juice content was studied. Citric acid was added to pure lychee dilutions in distilled water containing 100%, 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20% and 10% lychee juice. The pH of the dilutions was measured to obtain a linear model for the molar H+ concentration as a function of the added citric acid (g/L) amount LC = (BC-494.2)/12,031, where LC was the lychee juice content and BC was defined as the juice buffering coefficient.