Immunoglobulin Y(Ig Y)is an effective orally administered antibody used to protect against various intestinal pathogens,but which cannot tolerate the acidic gastric environment.In this study,Ig Y was microencapsulated...Immunoglobulin Y(Ig Y)is an effective orally administered antibody used to protect against various intestinal pathogens,but which cannot tolerate the acidic gastric environment.In this study,Ig Y was microencapsulated by alginate(ALG)and coated with chitooligosaccharide(COS).A response surface methodology was used to optimize the formulation,and a simulated gastrointestinal(GI)digestion(SGID)system to evaluate the controlled release of microencapsulated Ig Y.The microcapsule formulation was optimized as an ALG concentration of 1.56%(15.6 g/L),COS level of 0.61%(6.1 g/L),and Ig Y/ALG ratio of 62.44%(mass ratio).The microcapsules prepared following this formulation had an encapsulation efficiency of 65.19%,a loading capacity of 33.75%,and an average particle size of 588.75μm.Under this optimum formulation,the coating of COS provided a less porous and more continuous microstructure by filling the cracks on the surface,and thus the GI release rate of encapsulated Ig Y was significantly reduced.The release of encapsulated Ig Y during simulated gastric and intestinal digestion well fitted the zero-order and first-order kinetics functions,respectively.The microcapsule also allowed the Ig Y to retain 84.37%immune-activity after 4 h simulated GI digestion,significantly higher than that for unprotected Ig Y(5.33%).This approach could provide an efficient way to preserve Ig Y and improve its performance in the GI tract.展开更多
Phytopathogenic fungi cause heavy negative impact on the agricultural economy,but most existing fungicides are toxic and pose a threat to both human health and environments.A green and efficient fungicide is urgently ...Phytopathogenic fungi cause heavy negative impact on the agricultural economy,but most existing fungicides are toxic and pose a threat to both human health and environments.A green and efficient fungicide is urgently needed.Chitooligosaccharides(COSs),the degradation products of natural polysaccharide chitosan,are nontoxic and biodegradable antifungal substances.In this study,a novel type of aminourea chitooligosaccharide derivatives(AUCOS)was synthesized by successively grafting a hydrazine group and an amine-carbonyl group onto a chitooligosaccharide backbone to enhance the antifungal capability of COSs.The structures of the target compounds were identified by FTIR,1H NMR,and 13C NMR,and the degree of substitution of each product was calculated from the results of the elemental analysis.The antifungal activities of the prepared chitooligosaccharide derivatives against Fusarium solani,Verticillium albo-atrum and Phytophthora capsici were tested in vitro.The AUCOSs had better inhibitory efficiencies against the three plant pathogen fungi than that of chitooligosaccharide,of which aminourea chitooligosaccharide 2(AUCOS2)was the most promising antifungal compound,whose highest inhibition rates were 60.12%,82.95%,and 85.23%against F.solani,V.albo-atrum and P.capsici,respectively.The synthesized derivatives have good application prospects in crop protection and deserve further research.展开更多
基金Project supported by the National Key Research and Development Program of China(No.2018YFD0400305)the Modern Agro-industry Technology Research System of China(No.CARS-40-K26)the“One Belt and One Road”International Science and Technology Cooperation Program of Zhejiang,China(No.2019C04022)。
文摘Immunoglobulin Y(Ig Y)is an effective orally administered antibody used to protect against various intestinal pathogens,but which cannot tolerate the acidic gastric environment.In this study,Ig Y was microencapsulated by alginate(ALG)and coated with chitooligosaccharide(COS).A response surface methodology was used to optimize the formulation,and a simulated gastrointestinal(GI)digestion(SGID)system to evaluate the controlled release of microencapsulated Ig Y.The microcapsule formulation was optimized as an ALG concentration of 1.56%(15.6 g/L),COS level of 0.61%(6.1 g/L),and Ig Y/ALG ratio of 62.44%(mass ratio).The microcapsules prepared following this formulation had an encapsulation efficiency of 65.19%,a loading capacity of 33.75%,and an average particle size of 588.75μm.Under this optimum formulation,the coating of COS provided a less porous and more continuous microstructure by filling the cracks on the surface,and thus the GI release rate of encapsulated Ig Y was significantly reduced.The release of encapsulated Ig Y during simulated gastric and intestinal digestion well fitted the zero-order and first-order kinetics functions,respectively.The microcapsule also allowed the Ig Y to retain 84.37%immune-activity after 4 h simulated GI digestion,significantly higher than that for unprotected Ig Y(5.33%).This approach could provide an efficient way to preserve Ig Y and improve its performance in the GI tract.
基金Supported by the Shandong Province Key Research and Development Project(No.2018GHY115008)the Qingdao Science and Technology Project(No.17-3-3-60-nsh)。
文摘Phytopathogenic fungi cause heavy negative impact on the agricultural economy,but most existing fungicides are toxic and pose a threat to both human health and environments.A green and efficient fungicide is urgently needed.Chitooligosaccharides(COSs),the degradation products of natural polysaccharide chitosan,are nontoxic and biodegradable antifungal substances.In this study,a novel type of aminourea chitooligosaccharide derivatives(AUCOS)was synthesized by successively grafting a hydrazine group and an amine-carbonyl group onto a chitooligosaccharide backbone to enhance the antifungal capability of COSs.The structures of the target compounds were identified by FTIR,1H NMR,and 13C NMR,and the degree of substitution of each product was calculated from the results of the elemental analysis.The antifungal activities of the prepared chitooligosaccharide derivatives against Fusarium solani,Verticillium albo-atrum and Phytophthora capsici were tested in vitro.The AUCOSs had better inhibitory efficiencies against the three plant pathogen fungi than that of chitooligosaccharide,of which aminourea chitooligosaccharide 2(AUCOS2)was the most promising antifungal compound,whose highest inhibition rates were 60.12%,82.95%,and 85.23%against F.solani,V.albo-atrum and P.capsici,respectively.The synthesized derivatives have good application prospects in crop protection and deserve further research.
