Malus hupehensis was used as experiment materials.This experiments were conducted to explore the effects of benzoic acid on the productivity of superoxide（O2 ·）,the contents of malondialdehvde（MDA）and sulfhyd...Malus hupehensis was used as experiment materials.This experiments were conducted to explore the effects of benzoic acid on the productivity of superoxide（O2 ·）,the contents of malondialdehvde（MDA）and sulfhydryl group activity（—SH）,antioxidant enzyme activity and mineral elements in roots of M.hupehensis seedlings.The results showed that there was no significant difference between the treatment of 5 mg·kg-1（soil）benzoic acid and CK in above parameters.With 25 mg·kg-1（soil）and 125 mg·kg-1（soil）benzoic acid treatments,O2 · and MDA contents increased in the early period and then declined;—SH content decreased during the treatment time;activities of SOD and POD increased firstly,then decreased,CAT activity decreased firstly and then slightly reversed,but lower than that of CK;SOD,POD and CAT had a similar trend,activities of roots increased under 5 mg·kg-1（soil）benzoic acid,while they were inhibited by 25 mg·kg-1（soil）and 125 mg·kg-1（soil）benzoic acid;mineral elements were decreased.Benzoic acid in low concentration promoted antioxidant enzyme activity,—SH content,and uptake of mineral elements,reduced O2 · and MDA contents.In conclusion,benzoic acid of 5 mg·kg-1（soil）had no effects on Membrance Lipid Peroxidation and Antioxidant enzymes in roots of M.hupehensis seedlings;at 25 mg·kg-1（soil）and 125 mg·kg-1（soil）,benzoic acid increased Membrance Lipid Peroxidationd,decreased activity of antioxidant enzymes of roots,and damaged integrity and stability of cell membrane in M.hupehensis seedlings,meanwhile,contents of mineral elements were decreased.展开更多
Fifteen isomers of [Si,N,C,O]2+ system are obtained at UB3LYP/6-311G(d) and UCCSD(T)/6-311+G(2df) (single-point) levels. The analyses are made for predicting the structures of optimized isomers, while ionic fragments ...Fifteen isomers of [Si,N,C,O]2+ system are obtained at UB3LYP/6-311G(d) and UCCSD(T)/6-311+G(2df) (single-point) levels. The analyses are made for predicting the structures of optimized isomers, while ionic fragments with lower energies are suggested. The calculated results indicate that linear isomer SiNCO2+(2Π) is thermodynamically the most stable species in [Si,N,C,O]2+ system, followed by linear SiOCN2+ (2Π), SiCNO2+ (2Π), and SiC(NO) (2A) with NCO three-membered ring. The order of stability of several kinetically stable isomers is SiNCO2> SiCNO2+ (2Π)>SiOCN2+>SiC(NO)2+>OSiNC2+ (2Π). The obtained results by analyzing the isomerizations and ionic fragment patterns show that the signal peaks of [Si,N,C,O]2+ are attributed to the contribution of linear SiNCO2+ species, which is metastable and can dissociate to the ionic fragments in the mass spectrometry experiments.展开更多
以壳寡糖、2,4-二氯苯氧乙酸为原料,经壳寡糖氨基保护、2,4-二氯苯氧乙酸的羧基酰氯化、酰氯化后的2,4-二氯苯氧乙酸与壳寡糖羟基反应、脱除壳寡糖氨基保护最终得到2,4-二氯苯氧乙酸壳寡糖酯(Dcpo- O -COS)。通过傅里叶红外、紫外可见...以壳寡糖、2,4-二氯苯氧乙酸为原料,经壳寡糖氨基保护、2,4-二氯苯氧乙酸的羧基酰氯化、酰氯化后的2,4-二氯苯氧乙酸与壳寡糖羟基反应、脱除壳寡糖氨基保护最终得到2,4-二氯苯氧乙酸壳寡糖酯(Dcpo- O -COS)。通过傅里叶红外、紫外可见吸收、 1 H核磁共振对2,4-二氯苯氧乙酸壳寡糖酯进行了结构表征,证明成功合成终产物。经X射线衍射仪、热分析仪、抗菌性研究测定,终产物的热稳定性、对大肠杆菌及金黄色葡萄球菌的抗菌性较原料壳寡糖有所提高。展开更多
文摘Malus hupehensis was used as experiment materials.This experiments were conducted to explore the effects of benzoic acid on the productivity of superoxide（O2 ·）,the contents of malondialdehvde（MDA）and sulfhydryl group activity（—SH）,antioxidant enzyme activity and mineral elements in roots of M.hupehensis seedlings.The results showed that there was no significant difference between the treatment of 5 mg·kg-1（soil）benzoic acid and CK in above parameters.With 25 mg·kg-1（soil）and 125 mg·kg-1（soil）benzoic acid treatments,O2 · and MDA contents increased in the early period and then declined;—SH content decreased during the treatment time;activities of SOD and POD increased firstly,then decreased,CAT activity decreased firstly and then slightly reversed,but lower than that of CK;SOD,POD and CAT had a similar trend,activities of roots increased under 5 mg·kg-1（soil）benzoic acid,while they were inhibited by 25 mg·kg-1（soil）and 125 mg·kg-1（soil）benzoic acid;mineral elements were decreased.Benzoic acid in low concentration promoted antioxidant enzyme activity,—SH content,and uptake of mineral elements,reduced O2 · and MDA contents.In conclusion,benzoic acid of 5 mg·kg-1（soil）had no effects on Membrance Lipid Peroxidation and Antioxidant enzymes in roots of M.hupehensis seedlings;at 25 mg·kg-1（soil）and 125 mg·kg-1（soil）,benzoic acid increased Membrance Lipid Peroxidationd,decreased activity of antioxidant enzymes of roots,and damaged integrity and stability of cell membrane in M.hupehensis seedlings,meanwhile,contents of mineral elements were decreased.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.20171015,20171016)Science Foundation for Excellent Youths of Heilongjiang University(2002) and the Natural Science Foundation of Heilongjiang Province(Grant No.E0
文摘Fifteen isomers of [Si,N,C,O]2+ system are obtained at UB3LYP/6-311G(d) and UCCSD(T)/6-311+G(2df) (single-point) levels. The analyses are made for predicting the structures of optimized isomers, while ionic fragments with lower energies are suggested. The calculated results indicate that linear isomer SiNCO2+(2Π) is thermodynamically the most stable species in [Si,N,C,O]2+ system, followed by linear SiOCN2+ (2Π), SiCNO2+ (2Π), and SiC(NO) (2A) with NCO three-membered ring. The order of stability of several kinetically stable isomers is SiNCO2> SiCNO2+ (2Π)>SiOCN2+>SiC(NO)2+>OSiNC2+ (2Π). The obtained results by analyzing the isomerizations and ionic fragment patterns show that the signal peaks of [Si,N,C,O]2+ are attributed to the contribution of linear SiNCO2+ species, which is metastable and can dissociate to the ionic fragments in the mass spectrometry experiments.
文摘以壳寡糖、2,4-二氯苯氧乙酸为原料,经壳寡糖氨基保护、2,4-二氯苯氧乙酸的羧基酰氯化、酰氯化后的2,4-二氯苯氧乙酸与壳寡糖羟基反应、脱除壳寡糖氨基保护最终得到2,4-二氯苯氧乙酸壳寡糖酯(Dcpo- O -COS)。通过傅里叶红外、紫外可见吸收、 1 H核磁共振对2,4-二氯苯氧乙酸壳寡糖酯进行了结构表征,证明成功合成终产物。经X射线衍射仪、热分析仪、抗菌性研究测定,终产物的热稳定性、对大肠杆菌及金黄色葡萄球菌的抗菌性较原料壳寡糖有所提高。
