This study aimed to characterize and identify calcium-chelating peptides from rabbit bone collagen and explore the underlying chelating mechanism.Collagen peptides and calcium were extracted from rabbit bone by instan...This study aimed to characterize and identify calcium-chelating peptides from rabbit bone collagen and explore the underlying chelating mechanism.Collagen peptides and calcium were extracted from rabbit bone by instant ejection steam explosion(ICSE)combined with enzymatic hydrolysis,followed by chelation reaction to prepare rabbit bone peptide-calcium chelate(RBCP-Ca).The chelating sites were further analyzed by liquid chromatography-tandem mass(LC-MS/MS)spectrometry while the chelating mechanism and binding modes were investigated.The structural characterization revealed that RBCP successfully chelated with calcium ions.Furthermore,LC-MS/MS analysis indicated that the binding sites included both acidic amino acids(Asp and Glu)and basic amino acids(Lys and Arg),Interestingly,three binding modes,namely Inter-Linking,Loop-Linking and Mono-Linking were for the first time found,while Inter-Linking mode accounted for the highest proportion(75.1%),suggesting that chelation of calcium ions frequently occurred between two peptides.Overall,this study provides a theoretical basis for the elucidation of chelation mechanism of calcium-chelating peptides.展开更多
This experiment was conducted to investigate the effects of live yeast and yeast cell wall polysaccharides on growth performance,rumen function and plasma lipopolysaccharides(LPS) content and immunity parameters of be...This experiment was conducted to investigate the effects of live yeast and yeast cell wall polysaccharides on growth performance,rumen function and plasma lipopolysaccharides(LPS) content and immunity parameters of beef cattle.Forty Qinchuan cattle were randomly assigned to one of four treatments with 10 replicates in each treatment.The dietary treatments were: control diet(CTR),CTR supplemented with 1 g live yeast(2×10^10 live cell g^-1 per cattle per day(YST1),CTR supplemented with 2 g live yeast per cattle per day(YST2) and CTR supplemented with 20 g of yeast cell wall polysaccharides(30.0%≤β-glucan≤35.0%,and 28.0%≤mannanoligosaccharide≤32.0%) per cattle per day(YCW).The average daily gain was higher(P=0.023) and feed conversion ratio was lower(P=0.042) for the YST2 than the CTR.The digestibility of neutral detergent fiber(P=0.039) and acid detergent fiber(P=0.016) were higher in yeast supplemented groups.The acetic acid:propionic acid of the YST2 was lower compared with the CTR(P=0.033).Plasma LPS(P=0.032),acute phase protein haptoglobin(P=0.033),plasma amyloid A(P=0.015) and histamine(P=0.038) were lower in the YST2 compared with the CTR.The copies of fibrolytic microbial populations such as Fibrobacter succinogenes S85,Ruminococcus albus 7 and Ruminococcus flavefaciens FD-1 of the YST2 were higher(P<0.001),while the copies of typical lactate producing bacteria Streptococcus bovis JB1 was lower(P<0.001) compared with the CTR.Little differences were observed between the CTR,YST1 and YCW in growth performance,ruminal fermentation characteristics,microbial populations,immunity indices and total tract nutrient digestibility.It is concluded that the YST2 could promote fibrolytic microbial populations,decrease starch-utilizing bacteria,reduce LPS production in the rumen and LPS absorption into plasma and decrease inflammatory parameters,which can lead to an improvement in growth performance in beef cattle.展开更多
As a new type of sewage treatment technology,constructed wetland has high water purification ability and is receiving wider and wider attention. This paper comprehensively introduced the concept,building,classificatio...As a new type of sewage treatment technology,constructed wetland has high water purification ability and is receiving wider and wider attention. This paper comprehensively introduced the concept,building,classification,wastewater treatment mechanism of constructed wetland and its application in wastewater treatment of aquaculture.展开更多
为提高棕榈粕的饲用价值,本研究评估了12种不同甘露聚糖酶对棕榈粕中甘露聚糖的酶解效果,筛选酶的最适添加量,对比研究了直接发酵组(对照组)、甘露聚糖酶组、发酵菌剂组和甘露聚糖酶+发酵菌剂组的固态发酵效果及在禽和反刍上的体外仿生...为提高棕榈粕的饲用价值,本研究评估了12种不同甘露聚糖酶对棕榈粕中甘露聚糖的酶解效果,筛选酶的最适添加量,对比研究了直接发酵组(对照组)、甘露聚糖酶组、发酵菌剂组和甘露聚糖酶+发酵菌剂组的固态发酵效果及在禽和反刍上的体外仿生消化率。结果表明:在甘露聚糖酶添加量2‰时,8#酶的还原糖含量最高为6.46%(对照组1.9%),还原糖占甘露聚糖的比例由4%提升至14%;对0‰~10‰甘露聚糖酶添加量处理棕榈粕结果表明,在酶添加量8‰时,8#酶的还原糖含量最高为9.9%(对照组2.1%),还原糖占甘露聚糖的比例由4%提升到21%;四种方式处理棕榈粕发酵72 h,结果表明甘露聚糖酶+发酵菌剂组在pH、粗蛋白质(CP)、乳酸、还原糖、酸溶蛋白/粗蛋白质均显著高于其他各组(P<0.001);禽和反刍体外仿生消化结果表明,甘露聚糖酶+发酵菌剂组禽的干物质消化率(DDM)显著高于其他各组(P<0.001),反刍体外总产气量相比对照组从20 mL提升至70 m L左右,反刍体外发酵菌体蛋白(MCP)(P<0.001)、NH3-N(P=0.002)均显著高于对照组。综上,8#甘露聚糖酶在添加8‰,发酵菌剂添加2‰获得的发酵棕榈粕在气味和指标上较棕榈粕均有明显提升,同时在单胃动物和反刍动物仿生消化评估上均表现出明显优势。展开更多
Active dry yeast is dried by a certain way or retains most of its fermentation capacity,and it does not contain any grains or animal microbial preparations of other fillers.Its main components are active yeast thallus...Active dry yeast is dried by a certain way or retains most of its fermentation capacity,and it does not contain any grains or animal microbial preparations of other fillers.Its main components are active yeast thallus with content ≥90% and a small amount of emulsifier.In pig production,active dry yeast can enhance animal appetite,feed intake,animal growth,hindgut fermentation,breeding environment and anti-stress capability of animals,or reduce feed coefficient,animal constipation,incidence of swine and the number of pathogens in feces to prevent piglets from diarrhea.Studies have been proved that high active dry yeast has a very good application effect on sows,piglets and growing-finishing pigs.Active dry yeast in use should be noted that it should be used up within 3-6 months after being mixed with feed,while its dosage for pigs at different stages is as follows:nursery pigs of 500-1 000 g/t complete feed;sows of 500-800 g/t complete feed;fattening pigs of 250-500 g/t complete feed.Active dry yeast is very sensitive to the hot and humid,and is also not used in granulated feed and extruded feed.展开更多
[Objectives]To explore the influence of emulsifier on the fermentation performance of wine active dry yeast.[Methods]Angel active dry yeast RV002 was selected as the test strain,and the simulated grape juice was used ...[Objectives]To explore the influence of emulsifier on the fermentation performance of wine active dry yeast.[Methods]Angel active dry yeast RV002 was selected as the test strain,and the simulated grape juice was used as the fermentation medium to investigate the fermentation rate,the yeast cell number and morphology,and the physicochemical indexes of the produced wine.[Results]It was found that the viable cell rate of the active dry yeast without the emulsifier was significantly reduced,and the fermentation rate was significantly slowed down.However,the emulsifier had no significant effect on the morphology of yeast cells,the fermentation cycle,the final number of viable cells,and the quality of the produced wine.[Conclusions]The active dry wine yeast without emulsifier can reduce the formation of grape juice foam and reduce the risk of grape juice spillover.展开更多
基金granted by the National Key R&D Program of China (2021YFD21001005)National Natural Science Foundation of China (31972102,32101980)+1 种基金Special key project of Chongqing technology innovation and application development (cstc2021jscx-cylhX0014)Chongqing Technology Innovation and Application Development Special Project (cstc2021jscx-tpyzxX0014)。
文摘This study aimed to characterize and identify calcium-chelating peptides from rabbit bone collagen and explore the underlying chelating mechanism.Collagen peptides and calcium were extracted from rabbit bone by instant ejection steam explosion(ICSE)combined with enzymatic hydrolysis,followed by chelation reaction to prepare rabbit bone peptide-calcium chelate(RBCP-Ca).The chelating sites were further analyzed by liquid chromatography-tandem mass(LC-MS/MS)spectrometry while the chelating mechanism and binding modes were investigated.The structural characterization revealed that RBCP successfully chelated with calcium ions.Furthermore,LC-MS/MS analysis indicated that the binding sites included both acidic amino acids(Asp and Glu)and basic amino acids(Lys and Arg),Interestingly,three binding modes,namely Inter-Linking,Loop-Linking and Mono-Linking were for the first time found,while Inter-Linking mode accounted for the highest proportion(75.1%),suggesting that chelation of calcium ions frequently occurred between two peptides.Overall,this study provides a theoretical basis for the elucidation of chelation mechanism of calcium-chelating peptides.
基金the financial support from the National Key R&D Program of China (2017YFD0502005)the support of the Faculty of Veterinary and Agricultural Sciences Start-up Fund, The University of Melbourne, Australia
文摘This experiment was conducted to investigate the effects of live yeast and yeast cell wall polysaccharides on growth performance,rumen function and plasma lipopolysaccharides(LPS) content and immunity parameters of beef cattle.Forty Qinchuan cattle were randomly assigned to one of four treatments with 10 replicates in each treatment.The dietary treatments were: control diet(CTR),CTR supplemented with 1 g live yeast(2×10^10 live cell g^-1 per cattle per day(YST1),CTR supplemented with 2 g live yeast per cattle per day(YST2) and CTR supplemented with 20 g of yeast cell wall polysaccharides(30.0%≤β-glucan≤35.0%,and 28.0%≤mannanoligosaccharide≤32.0%) per cattle per day(YCW).The average daily gain was higher(P=0.023) and feed conversion ratio was lower(P=0.042) for the YST2 than the CTR.The digestibility of neutral detergent fiber(P=0.039) and acid detergent fiber(P=0.016) were higher in yeast supplemented groups.The acetic acid:propionic acid of the YST2 was lower compared with the CTR(P=0.033).Plasma LPS(P=0.032),acute phase protein haptoglobin(P=0.033),plasma amyloid A(P=0.015) and histamine(P=0.038) were lower in the YST2 compared with the CTR.The copies of fibrolytic microbial populations such as Fibrobacter succinogenes S85,Ruminococcus albus 7 and Ruminococcus flavefaciens FD-1 of the YST2 were higher(P<0.001),while the copies of typical lactate producing bacteria Streptococcus bovis JB1 was lower(P<0.001) compared with the CTR.Little differences were observed between the CTR,YST1 and YCW in growth performance,ruminal fermentation characteristics,microbial populations,immunity indices and total tract nutrient digestibility.It is concluded that the YST2 could promote fibrolytic microbial populations,decrease starch-utilizing bacteria,reduce LPS production in the rumen and LPS absorption into plasma and decrease inflammatory parameters,which can lead to an improvement in growth performance in beef cattle.
文摘As a new type of sewage treatment technology,constructed wetland has high water purification ability and is receiving wider and wider attention. This paper comprehensively introduced the concept,building,classification,wastewater treatment mechanism of constructed wetland and its application in wastewater treatment of aquaculture.
文摘为提高棕榈粕的饲用价值,本研究评估了12种不同甘露聚糖酶对棕榈粕中甘露聚糖的酶解效果,筛选酶的最适添加量,对比研究了直接发酵组(对照组)、甘露聚糖酶组、发酵菌剂组和甘露聚糖酶+发酵菌剂组的固态发酵效果及在禽和反刍上的体外仿生消化率。结果表明:在甘露聚糖酶添加量2‰时,8#酶的还原糖含量最高为6.46%(对照组1.9%),还原糖占甘露聚糖的比例由4%提升至14%;对0‰~10‰甘露聚糖酶添加量处理棕榈粕结果表明,在酶添加量8‰时,8#酶的还原糖含量最高为9.9%(对照组2.1%),还原糖占甘露聚糖的比例由4%提升到21%;四种方式处理棕榈粕发酵72 h,结果表明甘露聚糖酶+发酵菌剂组在pH、粗蛋白质(CP)、乳酸、还原糖、酸溶蛋白/粗蛋白质均显著高于其他各组(P<0.001);禽和反刍体外仿生消化结果表明,甘露聚糖酶+发酵菌剂组禽的干物质消化率(DDM)显著高于其他各组(P<0.001),反刍体外总产气量相比对照组从20 mL提升至70 m L左右,反刍体外发酵菌体蛋白(MCP)(P<0.001)、NH3-N(P=0.002)均显著高于对照组。综上,8#甘露聚糖酶在添加8‰,发酵菌剂添加2‰获得的发酵棕榈粕在气味和指标上较棕榈粕均有明显提升,同时在单胃动物和反刍动物仿生消化评估上均表现出明显优势。
文摘Active dry yeast is dried by a certain way or retains most of its fermentation capacity,and it does not contain any grains or animal microbial preparations of other fillers.Its main components are active yeast thallus with content ≥90% and a small amount of emulsifier.In pig production,active dry yeast can enhance animal appetite,feed intake,animal growth,hindgut fermentation,breeding environment and anti-stress capability of animals,or reduce feed coefficient,animal constipation,incidence of swine and the number of pathogens in feces to prevent piglets from diarrhea.Studies have been proved that high active dry yeast has a very good application effect on sows,piglets and growing-finishing pigs.Active dry yeast in use should be noted that it should be used up within 3-6 months after being mixed with feed,while its dosage for pigs at different stages is as follows:nursery pigs of 500-1 000 g/t complete feed;sows of 500-800 g/t complete feed;fattening pigs of 250-500 g/t complete feed.Active dry yeast is very sensitive to the hot and humid,and is also not used in granulated feed and extruded feed.
文摘[Objectives]To explore the influence of emulsifier on the fermentation performance of wine active dry yeast.[Methods]Angel active dry yeast RV002 was selected as the test strain,and the simulated grape juice was used as the fermentation medium to investigate the fermentation rate,the yeast cell number and morphology,and the physicochemical indexes of the produced wine.[Results]It was found that the viable cell rate of the active dry yeast without the emulsifier was significantly reduced,and the fermentation rate was significantly slowed down.However,the emulsifier had no significant effect on the morphology of yeast cells,the fermentation cycle,the final number of viable cells,and the quality of the produced wine.[Conclusions]The active dry wine yeast without emulsifier can reduce the formation of grape juice foam and reduce the risk of grape juice spillover.
