AIM： To investigate the hepatoprotective activity of tea polyphenols （TP） and its relation with cytochrome P450 （CYP450） expression in mice. METHODS： Hepatic CYP450 and CYPbs levels were measured by UV-spectroph...AIM： To investigate the hepatoprotective activity of tea polyphenols （TP） and its relation with cytochrome P450 （CYP450） expression in mice. METHODS： Hepatic CYP450 and CYPbs levels were measured by UV-spectrophotometry in mice 2 d after intraperitoneal TP （25, 50 and 100 mg/kg per day）. Then the mice were intragastricly pre-treated with TP （100, 200 and 400 mg/kg per day） for six days before paracetamol （1000 mg/kg） was given. Their acute mortality was compared with that of control mice. The mice were pre-treated with TP （100, 200, and 400 mg/kg per day） for five days before paracetamol （500 mg/kg） was given. Hepatic CYP2E1 and CYPIA2 protein and mRNA expression levels were evaluated by Western blotting, immunohistochemical staining and transcriptase-polymerase chain reaction. RESULTS： The hepatic CYP450 and CYPb5 levels in mice of TP-treated groups （100, 200 and 400 mg/kg per day） were decreased in a dose-dependent manner compared with those in the negative control mice.TP significantly attenuated the paracetamol-induced hepatic injury and dramatically reduced the mortality of paracetamol-treated mice. Furthermore, TP reduced CYP2E1 and CYPIA2 expression at both protein and mRNA levels in a dose-dependent manner. CONCLUSION： TP possess potential hepatoprotective properties and can suppress CYP450 expression.展开更多
As a potential source of fine chemicals, unripe apple polyphenols were extracted with Viscozyme L treatment. And then, a preparative moderate pressure liquid chromatography(MPLC) method for separation and purification...As a potential source of fine chemicals, unripe apple polyphenols were extracted with Viscozyme L treatment. And then, a preparative moderate pressure liquid chromatography(MPLC) method for separation and purification of polyphenols were successfully established by using silica gel column and octadesyl silane column. The structures of these compounds were identified by ~1H and ^(13)C NMR spectroscopy. The results indicated that Viscozyme L had the strongest effect on polyphenols extraction, the yield of apple crude polyphenols(ACP) was 7.08%, and the total phenolic content(TPC) of ACP was 0.95 g GAE/100 g, which were 2 times of that of control; 5 sub-fractions were obtained from ACP, which were A-1, A-2, and B-1, B-2, B-3; fractions A-2 and B-2 were identified as p-coumaric acid and caffeic acid and the yields were 111.54 and 161.70 mg/100 g ACP, respectively. In addition, p-coumaric acid and caffeic acid were the major components in Viscozyme L-aided polyphenols extraction, which could be explained by the result of degradation of lignin and chlorogenic acid by carbohydrate-hydrolyzing enzyme, Viscozyme L.展开更多
<span style="font-family:Verdana;">Phytochemical analysis shows that mahkota dewa fruit contains polyphenols. Mahkota dewa polyphenols have the ability to disrupt or reverse the stages of cancer or a c...<span style="font-family:Verdana;">Phytochemical analysis shows that mahkota dewa fruit contains polyphenols. Mahkota dewa polyphenols have the ability to disrupt or reverse the stages of cancer or a carcinogenesis process by affecting the intracellular signaling tissue molecules involved in an initiation and/or promotion. This chemopreventive potential is highly anticipating. The use, effectiveness, and benefits of the polyphenol have been empirically and pre-clinically proved without side effects. A multivariate analysis using Spearman’s test was conducted to examine the correlation between variables. Meanwhile, to determine which dependent variables played the strong role, a discriminant function analysis was performed with a significance level of p < 0.05 and a reliability level of 95%. The results showed that the mahkota dewa polyphenols acted as the suppressor agent by inducing apoptosis. This finding proved that polyphenols addition might result in death signal transduction through an apoptosis pathway which is either mediated by death receptor or mitochondria. The results of this study indicate that there is a relationship between apoptotic cell death mediated by death receptor and mitochondria through the administration of mahkota dewa polyphenols, it can be argued that mahkota dewa polyphenols can function in lung cancer chemoprevention in mice strain Balb/c.</span>展开更多
The Adsorption property of tea polyphenols(TP) by self-made macroporous crosslinked Poly(p-vinylbenzyl succinimide) resin(which can be abbreviated to PMVBS resin) were carried out through the static adsorption equilib...The Adsorption property of tea polyphenols(TP) by self-made macroporous crosslinked Poly(p-vinylbenzyl succinimide) resin(which can be abbreviated to PMVBS resin) were carried out through the static adsorption equilibrium and the dynamic column adsorption.The results suggested that the adsorption isotherms of the PMVBS resin for TP could be fitted to Langmuir adsorption equation with the coefficients larger than 0.99,the saturated adsorption capacities was 265 mg/g,the dynamic breakthrough capacity was 197 mg/g resin(dry),and 85 % ethanol solution was a good elution,elution rate was about 95%.The tea infusion was adsorbed and purified by the column of PMVBS resin,the purity of TP was above 96 %,and reusability of the resin was better.展开更多
Polyphenol oxidase （PPO） is the enzyme responsible for enzymatic browning during the growth of insects. It is also involved in defense reactions and is related with immunities in insects. PPO a metalloenzyme oxidase...Polyphenol oxidase （PPO） is the enzyme responsible for enzymatic browning during the growth of insects. It is also involved in defense reactions and is related with immunities in insects. PPO a metalloenzyme oxidase, catalyzes the oxidation of o-diphenol to o-quinone. The present paper describes the effects of benzaldehyde and its p-substituted derivatives on the activity of PPO from the fifth instar of Pieris rapae L. PPO from the fifth instar of Pieris rapae L. was purified using ammonium sulfate fractionation and chromatography on Sephadex G-100. The enzyme kinetics was characterized using L-3,4-dihydroxyphenylalanine （L-DOPA） as substrate. The results show that benzaldehyde, phydroxybenzaldehyde, p-chlorobenzaldehyde, and p-cyanobenzaldehyde can inhibit the PPO activity for the oxidation of L-DOPA. The inhibitor concentration leading to 50% activity lost, IC50, was estimated to be 5.90, 5.62, 2.83, and 2.91 mmol/L for the four tested inhibitors, respectively. Kinetic analyses show that the inhibitory effects of these compounds are reversible. Benzaldehyde, phydroxybenzaldehyde, and p-chlorobenzaldehyde are noncompetitive inhibitors while p-cyanobenzaldehyde is a mixed-type inhibitor. The inhibition constants were determined for all four inhibitors. p-chlorobenzaldehyde and p-cyanobenzaldehyde were more potent inhibitors than the other compounds. These results provide a basis for developing PPO inhibition-based pesticides.展开更多
This article aims to explain the inhibitory mechanism of thinned-young apple polyphenols(YAP)toward Fusobacterium nucleatum(F.nucleatum),Porphyromonas gingivalis(P.gingivalis)and Prevotella intermedia(P.intermedia).YA...This article aims to explain the inhibitory mechanism of thinned-young apple polyphenols(YAP)toward Fusobacterium nucleatum(F.nucleatum),Porphyromonas gingivalis(P.gingivalis)and Prevotella intermedia(P.intermedia).YAP has optimal antibacterial concentration against F.nucleatum(10.00 mg/mL),P.gingivalis(8.00 mg/mL)and P.intermedia(8.00 mg/mL),with viability of 47.97%,38.01%and 36.94%,respectively.Scanning electron microscopy(SEM)and confocal laser scanning microscopy(CLSM)observation revealed that YAP could cause the morphological changes of the halitosis-related bacterial cells and induce cell apoptosis.With the increase of YAP treatment concentrations,the permeability of the outer membranes(OM)and inner membranes(IM)of halitosis-related bacteria dramatically increased,resulting in the release of proteins and nucleic acids.In addition,bacterial cell membrane potential(MP)decreased after exposure to YAP.The results of this study provide new antibacterial agents for halitosis-related bacteria and find a new way for the development of thinned-young apples.展开更多
基金Grant from the Science Foundation of Educational Department of Liaoning Province,05L117Dalian Science&Technology Bureau,2007J22JH012
文摘AIM： To investigate the hepatoprotective activity of tea polyphenols （TP） and its relation with cytochrome P450 （CYP450） expression in mice. METHODS： Hepatic CYP450 and CYPbs levels were measured by UV-spectrophotometry in mice 2 d after intraperitoneal TP （25, 50 and 100 mg/kg per day）. Then the mice were intragastricly pre-treated with TP （100, 200 and 400 mg/kg per day） for six days before paracetamol （1000 mg/kg） was given. Their acute mortality was compared with that of control mice. The mice were pre-treated with TP （100, 200, and 400 mg/kg per day） for five days before paracetamol （500 mg/kg） was given. Hepatic CYP2E1 and CYPIA2 protein and mRNA expression levels were evaluated by Western blotting, immunohistochemical staining and transcriptase-polymerase chain reaction. RESULTS： The hepatic CYP450 and CYPb5 levels in mice of TP-treated groups （100, 200 and 400 mg/kg per day） were decreased in a dose-dependent manner compared with those in the negative control mice.TP significantly attenuated the paracetamol-induced hepatic injury and dramatically reduced the mortality of paracetamol-treated mice. Furthermore, TP reduced CYP2E1 and CYPIA2 expression at both protein and mRNA levels in a dose-dependent manner. CONCLUSION： TP possess potential hepatoprotective properties and can suppress CYP450 expression.
基金Supported by 333 Project in Jiangsu ProvinceQing Lan Project in Jiangsu Province
文摘As a potential source of fine chemicals, unripe apple polyphenols were extracted with Viscozyme L treatment. And then, a preparative moderate pressure liquid chromatography(MPLC) method for separation and purification of polyphenols were successfully established by using silica gel column and octadesyl silane column. The structures of these compounds were identified by ~1H and ^(13)C NMR spectroscopy. The results indicated that Viscozyme L had the strongest effect on polyphenols extraction, the yield of apple crude polyphenols(ACP) was 7.08%, and the total phenolic content(TPC) of ACP was 0.95 g GAE/100 g, which were 2 times of that of control; 5 sub-fractions were obtained from ACP, which were A-1, A-2, and B-1, B-2, B-3; fractions A-2 and B-2 were identified as p-coumaric acid and caffeic acid and the yields were 111.54 and 161.70 mg/100 g ACP, respectively. In addition, p-coumaric acid and caffeic acid were the major components in Viscozyme L-aided polyphenols extraction, which could be explained by the result of degradation of lignin and chlorogenic acid by carbohydrate-hydrolyzing enzyme, Viscozyme L.
文摘<span style="font-family:Verdana;">Phytochemical analysis shows that mahkota dewa fruit contains polyphenols. Mahkota dewa polyphenols have the ability to disrupt or reverse the stages of cancer or a carcinogenesis process by affecting the intracellular signaling tissue molecules involved in an initiation and/or promotion. This chemopreventive potential is highly anticipating. The use, effectiveness, and benefits of the polyphenol have been empirically and pre-clinically proved without side effects. A multivariate analysis using Spearman’s test was conducted to examine the correlation between variables. Meanwhile, to determine which dependent variables played the strong role, a discriminant function analysis was performed with a significance level of p < 0.05 and a reliability level of 95%. The results showed that the mahkota dewa polyphenols acted as the suppressor agent by inducing apoptosis. This finding proved that polyphenols addition might result in death signal transduction through an apoptosis pathway which is either mediated by death receptor or mitochondria. The results of this study indicate that there is a relationship between apoptotic cell death mediated by death receptor and mitochondria through the administration of mahkota dewa polyphenols, it can be argued that mahkota dewa polyphenols can function in lung cancer chemoprevention in mice strain Balb/c.</span>
文摘The Adsorption property of tea polyphenols(TP) by self-made macroporous crosslinked Poly(p-vinylbenzyl succinimide) resin(which can be abbreviated to PMVBS resin) were carried out through the static adsorption equilibrium and the dynamic column adsorption.The results suggested that the adsorption isotherms of the PMVBS resin for TP could be fitted to Langmuir adsorption equation with the coefficients larger than 0.99,the saturated adsorption capacities was 265 mg/g,the dynamic breakthrough capacity was 197 mg/g resin(dry),and 85 % ethanol solution was a good elution,elution rate was about 95%.The tea infusion was adsorbed and purified by the column of PMVBS resin,the purity of TP was above 96 %,and reusability of the resin was better.
基金Supported by the Science and Technology Foundation of Fujian Province (No. 2004N002)the National Natural Science Foundation of China (No. 30570408)
文摘Polyphenol oxidase （PPO） is the enzyme responsible for enzymatic browning during the growth of insects. It is also involved in defense reactions and is related with immunities in insects. PPO a metalloenzyme oxidase, catalyzes the oxidation of o-diphenol to o-quinone. The present paper describes the effects of benzaldehyde and its p-substituted derivatives on the activity of PPO from the fifth instar of Pieris rapae L. PPO from the fifth instar of Pieris rapae L. was purified using ammonium sulfate fractionation and chromatography on Sephadex G-100. The enzyme kinetics was characterized using L-3,4-dihydroxyphenylalanine （L-DOPA） as substrate. The results show that benzaldehyde, phydroxybenzaldehyde, p-chlorobenzaldehyde, and p-cyanobenzaldehyde can inhibit the PPO activity for the oxidation of L-DOPA. The inhibitor concentration leading to 50% activity lost, IC50, was estimated to be 5.90, 5.62, 2.83, and 2.91 mmol/L for the four tested inhibitors, respectively. Kinetic analyses show that the inhibitory effects of these compounds are reversible. Benzaldehyde, phydroxybenzaldehyde, and p-chlorobenzaldehyde are noncompetitive inhibitors while p-cyanobenzaldehyde is a mixed-type inhibitor. The inhibition constants were determined for all four inhibitors. p-chlorobenzaldehyde and p-cyanobenzaldehyde were more potent inhibitors than the other compounds. These results provide a basis for developing PPO inhibition-based pesticides.
基金supported by the National Natural Science Foundation of China(No.31701563)the Key Research and Development Program of Shaanxi Province(No.2019NY-124)+1 种基金Ministry of Education(XGZX 2021G08)the Fundamental Research Funds for the Central Universities at Shaanxi Normal University(1301031057).
文摘This article aims to explain the inhibitory mechanism of thinned-young apple polyphenols(YAP)toward Fusobacterium nucleatum(F.nucleatum),Porphyromonas gingivalis(P.gingivalis)and Prevotella intermedia(P.intermedia).YAP has optimal antibacterial concentration against F.nucleatum(10.00 mg/mL),P.gingivalis(8.00 mg/mL)and P.intermedia(8.00 mg/mL),with viability of 47.97%,38.01%and 36.94%,respectively.Scanning electron microscopy(SEM)and confocal laser scanning microscopy(CLSM)observation revealed that YAP could cause the morphological changes of the halitosis-related bacterial cells and induce cell apoptosis.With the increase of YAP treatment concentrations,the permeability of the outer membranes(OM)and inner membranes(IM)of halitosis-related bacteria dramatically increased,resulting in the release of proteins and nucleic acids.In addition,bacterial cell membrane potential(MP)decreased after exposure to YAP.The results of this study provide new antibacterial agents for halitosis-related bacteria and find a new way for the development of thinned-young apples.
