Quantitative Structure-Activity Relationship (2D-QSAR) models for binding affinity constants (log Ki) of 78 flavanoid ligands towards the benzodiazepine site of GABA (A) receptor complex were estimated using the PRECL...Quantitative Structure-Activity Relationship (2D-QSAR) models for binding affinity constants (log Ki) of 78 flavanoid ligands towards the benzodiazepine site of GABA (A) receptor complex were estimated using the PRECLAV (Property-Evaluation by Class Variables) program. The best MLR equation with nine PRECLAV descriptors has R2 = 0.843 and R2C = 0.782. Attempt is also made for obtaining 2D-QSAR model using NCSS software. The comparison of the results indicated that the PRECLAV method is very efficient in detecting structure-activity correlation with good predictive power.展开更多
Using naturally colored cotton(NCC)can eliminate dyeing,printing and industrial processing,and reduce sewage discharge and energy consumption.Proanthocyanidins(PAs),the primary coloration components in brown fibers,ar...Using naturally colored cotton(NCC)can eliminate dyeing,printing and industrial processing,and reduce sewage discharge and energy consumption.Proanthocyanidins(PAs),the primary coloration components in brown fibers,are polyphenols formed by oligomers or polymers of flavan-3-ol units derived from anthocyanidins.Three essential structural genes for flavanone and flavonoid hydroxylation encoding flavanone-3-hydroxylase(F3H),flavonoid 3’-hydroxylase(F3’H)and flavonoid 3’5’-hydroxylase(F3’5’H)are initially committed in the flavonoid biosynthesis pathway to produce common precursors.The three genes were all expressed predominantly in developing fibers of NCCs,and their expression patterns varied temporally and spatially among NCC varieties.In GhF3Hi,GhF3’Hi and GhF3’5’Hi silenced lines of NCC varieties XC20 and ZX1,the expression level of the three genes decreased in developing cotton fiber,negatively correlated with anthocyanidin content and fiber color depth.Fiber color depth and type in RNAi lines changed with endogenous gene silencing efficiency and expression pattern,the three hydroxylase genes functioned in fiber color formation.GhF3H showed functional differentiation among NCC varieties and GhF3’H acted in the accumulation of anthocyanin in fiber.Compared with GhF3’H,GhF3’5’H was expressed more highly in brown fiber with a longer duration of expression and caused lighter color of fibers in GhF3’5’H silenced lines.These three genes regulating fiber color depth and type could be used to improve these traits by genetic manipulation.展开更多
以牡丹叶为原料,采用酶法提取牡丹叶黄酮,以纤维素酶用量、p H值、酶解温度、酶解时间为单因素,以牡丹叶黄酮提取率为考察指标,通过正交试验确定酶法提取牡丹叶黄酮的最佳工艺参数为:纤维素酶用量12.5 U/m L、p H 4.5、酶解温度45℃、...以牡丹叶为原料,采用酶法提取牡丹叶黄酮,以纤维素酶用量、p H值、酶解温度、酶解时间为单因素,以牡丹叶黄酮提取率为考察指标,通过正交试验确定酶法提取牡丹叶黄酮的最佳工艺参数为:纤维素酶用量12.5 U/m L、p H 4.5、酶解温度45℃、酶解时间4 h。在此条件下牡丹叶黄酮提取率为2.43%。提取得到的牡丹叶黄酮浸提液可用于亚硝酸盐清除,通过正交试验优化得到牡丹叶黄酮清除亚硝酸盐的最佳反应条件为:反应温度70℃、p H 4.0、牡丹叶黄酮提取液添加量25 m L(10μg亚硝酸钠)、反应时间20 min。在此条件下牡丹叶黄酮对亚硝酸盐清除率可达62.15%。展开更多
文摘Quantitative Structure-Activity Relationship (2D-QSAR) models for binding affinity constants (log Ki) of 78 flavanoid ligands towards the benzodiazepine site of GABA (A) receptor complex were estimated using the PRECLAV (Property-Evaluation by Class Variables) program. The best MLR equation with nine PRECLAV descriptors has R2 = 0.843 and R2C = 0.782. Attempt is also made for obtaining 2D-QSAR model using NCSS software. The comparison of the results indicated that the PRECLAV method is very efficient in detecting structure-activity correlation with good predictive power.
基金supported by the Natural Science Foundation of Zhejiang Province(LZ21C130004)the National Natural Science Foundation of China(U1903204)he Fundamental Research Funds of Shaoxing Keqiao Research Institute of Zhejiang Sci-Tech University(KYY2021004S)。
文摘Using naturally colored cotton(NCC)can eliminate dyeing,printing and industrial processing,and reduce sewage discharge and energy consumption.Proanthocyanidins(PAs),the primary coloration components in brown fibers,are polyphenols formed by oligomers or polymers of flavan-3-ol units derived from anthocyanidins.Three essential structural genes for flavanone and flavonoid hydroxylation encoding flavanone-3-hydroxylase(F3H),flavonoid 3’-hydroxylase(F3’H)and flavonoid 3’5’-hydroxylase(F3’5’H)are initially committed in the flavonoid biosynthesis pathway to produce common precursors.The three genes were all expressed predominantly in developing fibers of NCCs,and their expression patterns varied temporally and spatially among NCC varieties.In GhF3Hi,GhF3’Hi and GhF3’5’Hi silenced lines of NCC varieties XC20 and ZX1,the expression level of the three genes decreased in developing cotton fiber,negatively correlated with anthocyanidin content and fiber color depth.Fiber color depth and type in RNAi lines changed with endogenous gene silencing efficiency and expression pattern,the three hydroxylase genes functioned in fiber color formation.GhF3H showed functional differentiation among NCC varieties and GhF3’H acted in the accumulation of anthocyanin in fiber.Compared with GhF3’H,GhF3’5’H was expressed more highly in brown fiber with a longer duration of expression and caused lighter color of fibers in GhF3’5’H silenced lines.These three genes regulating fiber color depth and type could be used to improve these traits by genetic manipulation.
文摘以牡丹叶为原料,采用酶法提取牡丹叶黄酮,以纤维素酶用量、p H值、酶解温度、酶解时间为单因素,以牡丹叶黄酮提取率为考察指标,通过正交试验确定酶法提取牡丹叶黄酮的最佳工艺参数为:纤维素酶用量12.5 U/m L、p H 4.5、酶解温度45℃、酶解时间4 h。在此条件下牡丹叶黄酮提取率为2.43%。提取得到的牡丹叶黄酮浸提液可用于亚硝酸盐清除,通过正交试验优化得到牡丹叶黄酮清除亚硝酸盐的最佳反应条件为:反应温度70℃、p H 4.0、牡丹叶黄酮提取液添加量25 m L(10μg亚硝酸钠)、反应时间20 min。在此条件下牡丹叶黄酮对亚硝酸盐清除率可达62.15%。