Methoxyl methyl ether isoamylene quercetin （MIAQ） is one of the newly synthesized quercetin derivatives. The present study investigated the effect of MIAQ on rat aorta endothelial cells （RAECs） injured by hydrogen...Methoxyl methyl ether isoamylene quercetin （MIAQ） is one of the newly synthesized quercetin derivatives. The present study investigated the effect of MIAQ on rat aorta endothelial cells （RAECs） injured by hydrogen peroxide （H2O2）, as well as the potential mechanisms. We observed that MIAQ at 2.5-10μmol/L significantly enhanced the viability of injured RAECs, and the effect was more potent than quercetin and ct-tocopherol. However, M1AQ at the same concentration failed to show anti-oxidant activity in a cell-free system. In H2O2-injured endothelial cells treated with MIAQ （5-10μmol/L）, the level of nitric oxide （NO） and malondialdehyde was decreased, and the activities of superoxide dismutase and glutathione peroxidase was enhanced. In addition, RAECs treated with MIAQ （2.5-10 μmol/L） exhibited significant inhibiting apoptosis. In conclusion, MIAQ had protective effect on RAECs, possibly through increasing NO production and antioxidases activities, as well as inhibiting apoptosis. These findings suggest that MIAQ is possibly beneficial in the prevention of atherosclerosis and other diseases related to endothelial injury.展开更多
Decabromodiphenyl ether （BDE209） is the primary component in a commonly used flame retardant. Previous studies had proved that BDE209 itself was not toxic, while its metabolites including debrominated diphenyl ethe...Decabromodiphenyl ether （BDE209） is the primary component in a commonly used flame retardant. Previous studies had proved that BDE209 itself was not toxic, while its metabolites including debrominated diphenyl ethers （De-BDEs） and methoxylated brominated diphenyl ethers （MeO-BDEs） posed a potential threat to organisms. Many studies had indicated that BDE209 could metabolize quickly in mammals, but lacking in the basic data about the metabolism of BDE209 in fish. In the present study, two replicate treatment groups of rainbow trout （Oncorhynchus rnykiss） were exposed to BDE209 via a single intraperitoneal injection approximately 100 and 500 ng/g, respectively. Muscle, liver and blood samples were collected to analyze the specific metabolites on day 1 and day 28 post injection. The highest concentration of BDE209 was detected in muscle tissues, from 796.1 ng/g wet weight （day 1） to 687.1 ng/g wet weight （day 28） in high dose group, suggesting that BDE209 could accumulate slightly in muscle tissues. However, BDE209 was not detected in the blood for all treatments. Most congeners of De-BDEs were found in muscle and liver tissues, with the highest concentration in the liver. The main De-BDEs were nona-, octa-, hepta- and penta-De-BDEs. A total of seven MeO-BDE metabolites were observed among different fish tissues. Blood had the highest contribution of the MeO-BDE metabolites. Each MeO-BDE congener increased over the 28 days. These results in contrast to other studies suggested possible species-specific differences in metabolic abilities.展开更多
The influence of different alcohol modifiers in mobile phase on the chiral separation of 4-methoxyl flavanone, 5-methoxyl flavanone and 6-methoxyl flavanone on cellulose tris (3, 5-dimethylphenylcarbamate) (CDMPC) col...The influence of different alcohol modifiers in mobile phase on the chiral separation of 4-methoxyl flavanone, 5-methoxyl flavanone and 6-methoxyl flavanone on cellulose tris (3, 5-dimethylphenylcarbamate) (CDMPC) column was studied and the chiral recognition mechanism was discussed. Using hexane-tert-butanol (1.31 mol L-1) as the mobile phase, those three methoxyl flavanones were excellently separated on CDMPC chiral column.展开更多
Two new metal-organic frameworks, [Co3L2（NO2）2（H2O）2],, （1） and{[Ni（L）（H2O）5] （H2O）2.DMF}, （2, H2L = 5-（4-pyridyl）-methoxyl isophthalic acid）, have been synthesized by the hydrothermal method and chara...Two new metal-organic frameworks, [Co3L2（NO2）2（H2O）2],, （1） and{[Ni（L）（H2O）5] （H2O）2.DMF}, （2, H2L = 5-（4-pyridyl）-methoxyl isophthalic acid）, have been synthesized by the hydrothermal method and characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis （TGA） and X-ray crystallography. Compound 1 crystallizes in the monoclinic system with space group P2/c and adopts a slightly distorted octahedral configuration. In compound 1, the 2D bilayered structures are linked by O-H...O and O-H...N hydrogen bonds to form a 3D framework. Compound 2 crystallizes in the monoclinic system with space group P2/n, and the central nickel atoms are octa-coordinated with five O atoms from coordinated water molecules and one N atom from one H2L ligand. The abundant O-H…O hydrogen bonds and π…π interactions link the molecules into a 3D framework. In addition, compounds 1 and 2 exhibit strong ultraviolet absorption in the solid state at room temperature.展开更多
Methoxylated flavonoids isolated from cold acetone leaf wash of Polygonum senegalense;5-hydroxy-7-methoxyflavanone 1 and 5-hydroxy-6,7-dimethoxy-flavanone 3, were tested for their ability to enhance thermal stability ...Methoxylated flavonoids isolated from cold acetone leaf wash of Polygonum senegalense;5-hydroxy-7-methoxyflavanone 1 and 5-hydroxy-6,7-dimethoxy-flavanone 3, were tested for their ability to enhance thermal stability of vegetable oils. Determination of the peroxide value (P.V.) and the p-Anisidine value (p-A.V.) was done according to the standard methods of analysis. The compounds were tested for in vitro cytotoxicity against a mammalian cell-line, Chinese Hamster Ovarian (CHO) using the 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazoliumbromide (MTT)-assay. Studies on changes in peroxide and p-Anisidine values for the oils heated to temperatures between 180°C and 200°C recorded better stability enhancement at 100 ppm concentration with these flavonoids than the commercial antioxidant, butylated hydroxytoluene (BHT). The plant-based flavonoids had no significant cytotoxic effect against the CHO cell-line and may serve as alternative antioxidants to synthetic ones which have previously raised great concern over the health of consumers.展开更多
In recent years,the trifluoromethoxy(OCF3)functional group has received extensive attention in phar-maceuticals,agrochemicals and material sciences.However,the methods for the enantioselective syn-thesis of trifluorom...In recent years,the trifluoromethoxy(OCF3)functional group has received extensive attention in phar-maceuticals,agrochemicals and material sciences.However,the methods for the enantioselective syn-thesis of trifluoromethoxylated stereogenic carbon centers are rare owing to the nature of easy decom-position of OCF3 anion and limited OCF3 reagent.And the asymmetric trifluoromethoxylation will be a hot research topic in near future due to the unique biological properties of a single isomer.This article mainly focuses on the recent advances in the enantioselectiveconstruction of trifluoromethoxylated stereogenic carbon centers.展开更多
We have reported H-Mordenite-catalyzed alkoxylation of camphene and tricyclene with C<sub>1</sub>--C<sub>4</sub> alcohols, and discussed the relationship of the structure to the odor of a serie...We have reported H-Mordenite-catalyzed alkoxylation of camphene and tricyclene with C<sub>1</sub>--C<sub>4</sub> alcohols, and discussed the relationship of the structure to the odor of a series of major products. Alkoxylation of α-pinene （3） and β-pinene （5）, which are catalyzed by strongly acidic cation exchange resin, boron-trifluoride ether-展开更多
A novel continuous flow method for the methoxylation of chloronitrobenzenes was developed. The reaction went smoothly and high yields were achieved under the optimized conditions. Furthermore, up to 76% yield of azoxy...A novel continuous flow method for the methoxylation of chloronitrobenzenes was developed. The reaction went smoothly and high yields were achieved under the optimized conditions. Furthermore, up to 76% yield of azoxybenzenes were obtained from the corresponding nitrobenzenes in the presence of NaOH in continuous flow. Compared to batch conditions, the reaction time was significantly shortened, and the chemical waste was reduced obviously.展开更多
Quercetin(Que)is a popular polyphenol with various activities.However,its application was limited due to its poor water solubility,stability,and low bioavailability.In this study,pea protein isolate(PPI)and high metho...Quercetin(Que)is a popular polyphenol with various activities.However,its application was limited due to its poor water solubility,stability,and low bioavailability.In this study,pea protein isolate(PPI)and high methoxyl pectin(HMP)complexes were fabricated to encapsulate and protect Que.Soluble PPI-HMP complexes at pH 5 and pH 6 were selected based on phase diagram of the two biopolymers during acidification.Fluorescence quenching experiments indicated that complex at pH 5 showed higher binding affinity towards Que than that at pH 6.Complexes at pH 5 displayed considerably higher encapsulation efficiency and loading ability with Que than those at pH 6.XRD results indicated that Que may be transformed from crystalloid to amorphous state after encapsulation.Photochemical and thermal stabilities of Que were improved by complexing with PPI-HMP nanocomplexes at both pH values.Encapsulation improved the 2,2-diphenyl-1-picrylhydrazyl(DPPH)and 2,2′-azinobis(2-ethylbenzothiazoline-6-sulfonate)(ABTS)free radical scavenging ability of Que and complex at pH 6 had higher antioxidative ability.The in vitro release study showed that Que displayed initial burst release followed by sustained release in simulated intestinal fluid and higher percentage of Que was released in complex at pH 6 than at pH 5.Data obtained may provide useful information for fabricating pea protein based effective delivery system for Que.展开更多
Voltammetric behavior of sodium 7-methoxyl-4'-hydroxylisoflavone-3'-sulfonate (SMHS) in the aqueous solu-tion from pH 1 to 5 was studied by linear sweep voltammetry, cyclic voltammetry and normal pulse voltamm...Voltammetric behavior of sodium 7-methoxyl-4'-hydroxylisoflavone-3'-sulfonate (SMHS) in the aqueous solu-tion from pH 1 to 5 was studied by linear sweep voltammetry, cyclic voltammetry and normal pulse voltammetry. Experimental results showed that in 0.2 molL-1 sodium citrate-hydrochloric acid buffer solution (pH=4.65), SMHS caused only one reduction wave at -1.34 V (vs. saturated calomel electrode, SCE), which was an irreversi-ble adsorptive wave of SMHS protonized involving one electron and one proton. The peak current of SMHS on lin-ear sweep voltammogram was proportional to its concentration in the range of 8.0×10-6—8.0×10-5 molL-1 (r=0.995), and the detection limit was 5.0×10-6 mol昄-1. The method was applied to determination of SMHS in syn-thetic samples. In addition, its scavenging effect on superoxide anion radical was studied by the auto-oxidation of pyrogallol in HCl-tris buffer solution (pH=8.2) in order to explain its peculiar biological effects. The experimental results proved that SMHS has antioxidant quality, and it is an efficient free radical scavenger of superoxide anion radical.展开更多
针对油脂蛋白多糖多重乳液体系在热力杀菌过程中因发生乳清蛋白变性团聚而引起的乳液不稳定现象,通过精氨酸(Arg)和低酯果胶(LMP)对蛋白胶束表面电荷和胶束结构的修饰作用,形成相应的精氨酸乳清蛋白复合物(Arg-whey protein complex,AW...针对油脂蛋白多糖多重乳液体系在热力杀菌过程中因发生乳清蛋白变性团聚而引起的乳液不稳定现象,通过精氨酸(Arg)和低酯果胶(LMP)对蛋白胶束表面电荷和胶束结构的修饰作用,形成相应的精氨酸乳清蛋白复合物(Arg-whey protein complex,AWPC)和精氨酸乳清蛋白低酯果胶复合物(Arg-whey protein-low methoxyl pectin complex,AWPPC)。研究结果表明:通过Arg复合修饰、热力杀菌(121℃,15 min)后油脂蛋白多糖多重乳液体系的平均粒径减小39.1%,Zeta电位绝对值增加17.6%,乳化活性指数(EAI)提高18.7%,冻融和杀菌处理的冷热稳定性显著提高。当Arg和LMP的最佳质量比为0.15∶0.70时,AWPPC溶液的EAI达到最大值6.10 m 2/g。展开更多
基金National Natural Science Foundation of China (Grant No. 61071002)
文摘Methoxyl methyl ether isoamylene quercetin （MIAQ） is one of the newly synthesized quercetin derivatives. The present study investigated the effect of MIAQ on rat aorta endothelial cells （RAECs） injured by hydrogen peroxide （H2O2）, as well as the potential mechanisms. We observed that MIAQ at 2.5-10μmol/L significantly enhanced the viability of injured RAECs, and the effect was more potent than quercetin and ct-tocopherol. However, M1AQ at the same concentration failed to show anti-oxidant activity in a cell-free system. In H2O2-injured endothelial cells treated with MIAQ （5-10μmol/L）, the level of nitric oxide （NO） and malondialdehyde was decreased, and the activities of superoxide dismutase and glutathione peroxidase was enhanced. In addition, RAECs treated with MIAQ （2.5-10 μmol/L） exhibited significant inhibiting apoptosis. In conclusion, MIAQ had protective effect on RAECs, possibly through increasing NO production and antioxidases activities, as well as inhibiting apoptosis. These findings suggest that MIAQ is possibly beneficial in the prevention of atherosclerosis and other diseases related to endothelial injury.
基金supported by the National Basic Research Program (973) of China (No. 2009CB421605)the National Natural Science Foundation of China (No.20877089,20737003)
文摘Decabromodiphenyl ether （BDE209） is the primary component in a commonly used flame retardant. Previous studies had proved that BDE209 itself was not toxic, while its metabolites including debrominated diphenyl ethers （De-BDEs） and methoxylated brominated diphenyl ethers （MeO-BDEs） posed a potential threat to organisms. Many studies had indicated that BDE209 could metabolize quickly in mammals, but lacking in the basic data about the metabolism of BDE209 in fish. In the present study, two replicate treatment groups of rainbow trout （Oncorhynchus rnykiss） were exposed to BDE209 via a single intraperitoneal injection approximately 100 and 500 ng/g, respectively. Muscle, liver and blood samples were collected to analyze the specific metabolites on day 1 and day 28 post injection. The highest concentration of BDE209 was detected in muscle tissues, from 796.1 ng/g wet weight （day 1） to 687.1 ng/g wet weight （day 28） in high dose group, suggesting that BDE209 could accumulate slightly in muscle tissues. However, BDE209 was not detected in the blood for all treatments. Most congeners of De-BDEs were found in muscle and liver tissues, with the highest concentration in the liver. The main De-BDEs were nona-, octa-, hepta- and penta-De-BDEs. A total of seven MeO-BDE metabolites were observed among different fish tissues. Blood had the highest contribution of the MeO-BDE metabolites. Each MeO-BDE congener increased over the 28 days. These results in contrast to other studies suggested possible species-specific differences in metabolic abilities.
文摘The influence of different alcohol modifiers in mobile phase on the chiral separation of 4-methoxyl flavanone, 5-methoxyl flavanone and 6-methoxyl flavanone on cellulose tris (3, 5-dimethylphenylcarbamate) (CDMPC) column was studied and the chiral recognition mechanism was discussed. Using hexane-tert-butanol (1.31 mol L-1) as the mobile phase, those three methoxyl flavanones were excellently separated on CDMPC chiral column.
基金supported by the National Natural Science Foundation of China (No.20971065)the National Basic Research Program of China (No.2010CB923303)
文摘Two new metal-organic frameworks, [Co3L2（NO2）2（H2O）2],, （1） and{[Ni（L）（H2O）5] （H2O）2.DMF}, （2, H2L = 5-（4-pyridyl）-methoxyl isophthalic acid）, have been synthesized by the hydrothermal method and characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis （TGA） and X-ray crystallography. Compound 1 crystallizes in the monoclinic system with space group P2/c and adopts a slightly distorted octahedral configuration. In compound 1, the 2D bilayered structures are linked by O-H...O and O-H...N hydrogen bonds to form a 3D framework. Compound 2 crystallizes in the monoclinic system with space group P2/n, and the central nickel atoms are octa-coordinated with five O atoms from coordinated water molecules and one N atom from one H2L ligand. The abundant O-H…O hydrogen bonds and π…π interactions link the molecules into a 3D framework. In addition, compounds 1 and 2 exhibit strong ultraviolet absorption in the solid state at room temperature.
文摘Methoxylated flavonoids isolated from cold acetone leaf wash of Polygonum senegalense;5-hydroxy-7-methoxyflavanone 1 and 5-hydroxy-6,7-dimethoxy-flavanone 3, were tested for their ability to enhance thermal stability of vegetable oils. Determination of the peroxide value (P.V.) and the p-Anisidine value (p-A.V.) was done according to the standard methods of analysis. The compounds were tested for in vitro cytotoxicity against a mammalian cell-line, Chinese Hamster Ovarian (CHO) using the 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazoliumbromide (MTT)-assay. Studies on changes in peroxide and p-Anisidine values for the oils heated to temperatures between 180°C and 200°C recorded better stability enhancement at 100 ppm concentration with these flavonoids than the commercial antioxidant, butylated hydroxytoluene (BHT). The plant-based flavonoids had no significant cytotoxic effect against the CHO cell-line and may serve as alternative antioxidants to synthetic ones which have previously raised great concern over the health of consumers.
文摘In recent years,the trifluoromethoxy(OCF3)functional group has received extensive attention in phar-maceuticals,agrochemicals and material sciences.However,the methods for the enantioselective syn-thesis of trifluoromethoxylated stereogenic carbon centers are rare owing to the nature of easy decom-position of OCF3 anion and limited OCF3 reagent.And the asymmetric trifluoromethoxylation will be a hot research topic in near future due to the unique biological properties of a single isomer.This article mainly focuses on the recent advances in the enantioselectiveconstruction of trifluoromethoxylated stereogenic carbon centers.
基金Project supported by the National Natural Science Foundation of China.
文摘We have reported H-Mordenite-catalyzed alkoxylation of camphene and tricyclene with C<sub>1</sub>--C<sub>4</sub> alcohols, and discussed the relationship of the structure to the odor of a series of major products. Alkoxylation of α-pinene （3） and β-pinene （5）, which are catalyzed by strongly acidic cation exchange resin, boron-trifluoride ether-
基金This Science work was supported by the National Natural Foundation of China （Nos. 21502090, 21522604）, Natural Science Foundation of Jiangsu Province （Nos. BK20150942, BK20150031） and the National Key Basic Research Program of China （No. 2012CB725204）. We also thank the financial support from Top-notch Academic Programs Project of Jiangsu Higher Education Institutions （TAPP）.
文摘A novel continuous flow method for the methoxylation of chloronitrobenzenes was developed. The reaction went smoothly and high yields were achieved under the optimized conditions. Furthermore, up to 76% yield of azoxybenzenes were obtained from the corresponding nitrobenzenes in the presence of NaOH in continuous flow. Compared to batch conditions, the reaction time was significantly shortened, and the chemical waste was reduced obviously.
基金supported by Key Scientific&Technological Projects of Jilin Provincial Science and Technology Department(Project no.20210204036YY).
文摘Quercetin(Que)is a popular polyphenol with various activities.However,its application was limited due to its poor water solubility,stability,and low bioavailability.In this study,pea protein isolate(PPI)and high methoxyl pectin(HMP)complexes were fabricated to encapsulate and protect Que.Soluble PPI-HMP complexes at pH 5 and pH 6 were selected based on phase diagram of the two biopolymers during acidification.Fluorescence quenching experiments indicated that complex at pH 5 showed higher binding affinity towards Que than that at pH 6.Complexes at pH 5 displayed considerably higher encapsulation efficiency and loading ability with Que than those at pH 6.XRD results indicated that Que may be transformed from crystalloid to amorphous state after encapsulation.Photochemical and thermal stabilities of Que were improved by complexing with PPI-HMP nanocomplexes at both pH values.Encapsulation improved the 2,2-diphenyl-1-picrylhydrazyl(DPPH)and 2,2′-azinobis(2-ethylbenzothiazoline-6-sulfonate)(ABTS)free radical scavenging ability of Que and complex at pH 6 had higher antioxidative ability.The in vitro release study showed that Que displayed initial burst release followed by sustained release in simulated intestinal fluid and higher percentage of Que was released in complex at pH 6 than at pH 5.Data obtained may provide useful information for fabricating pea protein based effective delivery system for Que.
基金the National Natural Science Foundation of China (No. 20275030) the Key Item of Science and Technique by the Ministry of Education (No. 02187) the Foundation for University Key Teacher by the Ministry of Education (No. GG-150-71006-2
文摘Voltammetric behavior of sodium 7-methoxyl-4'-hydroxylisoflavone-3'-sulfonate (SMHS) in the aqueous solu-tion from pH 1 to 5 was studied by linear sweep voltammetry, cyclic voltammetry and normal pulse voltammetry. Experimental results showed that in 0.2 molL-1 sodium citrate-hydrochloric acid buffer solution (pH=4.65), SMHS caused only one reduction wave at -1.34 V (vs. saturated calomel electrode, SCE), which was an irreversi-ble adsorptive wave of SMHS protonized involving one electron and one proton. The peak current of SMHS on lin-ear sweep voltammogram was proportional to its concentration in the range of 8.0×10-6—8.0×10-5 molL-1 (r=0.995), and the detection limit was 5.0×10-6 mol昄-1. The method was applied to determination of SMHS in syn-thetic samples. In addition, its scavenging effect on superoxide anion radical was studied by the auto-oxidation of pyrogallol in HCl-tris buffer solution (pH=8.2) in order to explain its peculiar biological effects. The experimental results proved that SMHS has antioxidant quality, and it is an efficient free radical scavenger of superoxide anion radical.
文摘针对油脂蛋白多糖多重乳液体系在热力杀菌过程中因发生乳清蛋白变性团聚而引起的乳液不稳定现象,通过精氨酸(Arg)和低酯果胶(LMP)对蛋白胶束表面电荷和胶束结构的修饰作用,形成相应的精氨酸乳清蛋白复合物(Arg-whey protein complex,AWPC)和精氨酸乳清蛋白低酯果胶复合物(Arg-whey protein-low methoxyl pectin complex,AWPPC)。研究结果表明:通过Arg复合修饰、热力杀菌(121℃,15 min)后油脂蛋白多糖多重乳液体系的平均粒径减小39.1%,Zeta电位绝对值增加17.6%,乳化活性指数(EAI)提高18.7%,冻融和杀菌处理的冷热稳定性显著提高。当Arg和LMP的最佳质量比为0.15∶0.70时,AWPPC溶液的EAI达到最大值6.10 m 2/g。
