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Determination of Total Polyphenols in Different Extraction Fractions of Pholidota chinensis Lindl.and Their Antioxidant Activity 被引量:1
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作者 Miao ZHANG Guini XIE +2 位作者 Jing LUO Long CHEN Hua ZHU 《Agricultural Biotechnology》 CAS 2022年第6期109-112,115,共5页
[Objectives]This study was conducted to study the total polyphenol content and antioxidant capacity of different extraction fractions of Pholidota chinensis.[Methods]Different polar fractions of P.chinensis were obtai... [Objectives]This study was conducted to study the total polyphenol content and antioxidant capacity of different extraction fractions of Pholidota chinensis.[Methods]Different polar fractions of P.chinensis were obtained by ultrasonic extraction method,and determined for polyphenol contents by UV spectrophotometry,and their antioxidant activity was evaluated by DPPH free radical scavenging and ferric ion reducing antioxidant power(FRAP).SPSS analysis software was used to analyze the correlation between total polyphenol contents and antioxidant activity of different extracts.[Results]The contents of total polyphenols in different polar fractions ranged from 1.52 to 6.41 mg/g,and the order from low to high was:water<petroleum ether<ethyl acetate<95%ethanol.The reduction capacity of the total antioxidant capacity method ranged from 12.54 to 22.45μmol/L,and the order was 95%ethanol>ethyl acetate>petroleum ether>water.The DPPH median inhibition concentration ranged from 0.35 to 2.65 mg/ml,and the order was water>petroleum ether>ethyl acetate>95%ethanol.The total polyphenol content of P.chinensis was best in the 95%ethanol extraction fraction,which showed the strongest total antioxidant capacity,so the total polyphenol content of the 95%ethanol fraction was positively correlated with its antioxidant capacity,while the DPPH free radical-scavenging capacity was better in the water fraction,indicating that the free radical-scavenging capacity of the water fraction was better.[Conclusions]This study provides a theoretical basis for the further study of the chemical components of P.chinensis and the development and utilization of natural antioxidants. 展开更多
关键词 Pholidota chinensis Lindl. EXTRACTION total polyphenol content Antioxidant activity
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Effects of Pulp Preconditioning on Total Polyphenols, O-diphenols and Anthocyanin Concentrations during Fermentation and Drying of Cocoa (Theobroma cacao) Beans 被引量:1
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作者 Emmanuel Ohene Afoakwa John Edem Kongor +2 位作者 Jemmy Felix Takrama Agnes Simpson Budu Henry Mensah-Brown 《Journal of Food Science and Engineering》 2013年第5期235-245,共11页
Changes in total polyphenols, O-diphenols and anthocyanin concentrations during fermentation and drying of pulp pre-conditioned cocoa (Theobroma cacao) beans were investigated using standard analytical methods. Incr... Changes in total polyphenols, O-diphenols and anthocyanin concentrations during fermentation and drying of pulp pre-conditioned cocoa (Theobroma cacao) beans were investigated using standard analytical methods. Increasing pod storage, fermentation and drying led to variable reductions in total polyphenols, O-diphenols and anthocyanins content of the beans. The rates of reduction were however more pronounced during fermentation than pod storage and drying. Storage of cocoa pods between 3-7 days with 6 and 7 days of fermentation and drying respectively retained 85%-90% of the total polyphenol and O-diphenols of the cocoa beans. Similarly, anthocyanin content of beans from the 10 days of pod storage decreased by 70% in the sixth day of fermentation. Pod storage decreased the anthocyanin content at all periods of fermentation. These suggest that the post-harvest treatments of pod storage, fermentation and drying all results in variable reductions in polyphenolic content (total polyphenols and O-diphenols) and anthocyanins content of cocoa beans. 展开更多
关键词 Theobroma cacao pod storage pulp pre-conditioning FERMENTATION DRYING total polyphenols O-diphenols anthocyanins.
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Preparation and Drug-Release Property of Polycaprolactone (PCL)/Polyglycolic Acid (PGA) Composite Masterbatch with Drug of Tea Polyphenols (TPs)
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作者 吴改红 刘淑强 +6 位作者 杨雅茹 莫易涵 李杰特 李静静 张菂 杨智超 陆东东 《Journal of Donghua University(English Edition)》 CAS 2023年第3期277-283,共7页
In order to effectively control the drug-release rate of medical textiles,biodegradable polycaprolactone(PCL) and polyglycolic acid(PGA) were blended at various mass ratios to prepare composite masterbatches for medic... In order to effectively control the drug-release rate of medical textiles,biodegradable polycaprolactone(PCL) and polyglycolic acid(PGA) were blended at various mass ratios to prepare composite masterbatches for medical textiles.The surface morphology and the chemical structure of the masterbatches were analyzed.The crystallization,mass losses,strengths and drug-release rates of the composite masterbatches at different PCL/PGA mass ratios were explored.The results show that the degradation rate of the PGA carrier is obvious higher than that of the PCL carrier,and PCL,PGA and the tea polyphenol(TP) drug just physically mix without chemical reaction.During the degradation,the strength of the composite masterbatches gradually decreases.In addition,the drug-release rates of composite masterbatches at different mass ratios are different,and the more the PGA in the composite masterbatches,the faster the drug release of the composite masterbatches.The drug-release rate of the composite masterbatches can be controlled by adjusting the contents of PCL and PGA. 展开更多
关键词 polycaprolactone(PCL) polyglycolic acid(PGA) tea polyphenol(tp) composite masterbatch drug release
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Tea Polyphenols Exerts Anti-hepatitis B Virus Effects in a Stably HBV-transfected Cell Line 被引量:4
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作者 叶翩 张淑玲 +4 位作者 赵雷 董继华 揭盛华 庞然 李淑莉 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2009年第2期169-172,共4页
In this study, the anti-HBV effects of tea polyphenols (TP) were examined. After cells were exposed to TP for 3, 6, 9 days, amounts of HBsAg, HBeAg and HBV-DNA released into the supernatant of the cultured HepG2 2.2... In this study, the anti-HBV effects of tea polyphenols (TP) were examined. After cells were exposed to TP for 3, 6, 9 days, amounts of HBsAg, HBeAg and HBV-DNA released into the supernatant of the cultured HepG2 2.2.15 cells were detected. TP, to some extent, inhibited the secretion of HBsAg and strongly suppressed the secretion of HBeAg in a dose-dependent (P〈0.01) and time-dependent manner, with 50% maximal inhibitory concentration (IC50) value being 7.34μg/mL on the 9th day, but the time-dependence was not significant (P=0.051). Expression of HBV-DNA in the supernatant of the cell culture also was significantly decreased in a dose-dependent fashion (P〈0.01). The ICS0 of TP in inhibiting HBV DNA was 2.54 pg/mL. It concluded that TP possessed potential anti-HBV effects and may be used as a treatment alternative for HBV infection. 展开更多
关键词 liver diseases hepatitis B virus anti-HBV effect tea polyphenols (tp HepG2 2.2.15
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Study on Polyphenol Oxidase Activity and Total Phenol Content of Docynia indica 被引量:1
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作者 Xiaobo QIN Xinyi XU +4 位作者 Bei NIU Xiaodong SHI Bingbing ZHANG Lijuan FAN Dongmei HU 《Medicinal Plant》 CAS 2019年第4期73-75,83,共4页
[Objectives] To study the polyphenol oxidase (PPO) activity and total phenol content of Docynia indica .[Methods] The tender branches and petioles of the medicinal and edible plant D. indica were used as experimental ... [Objectives] To study the polyphenol oxidase (PPO) activity and total phenol content of Docynia indica .[Methods] The tender branches and petioles of the medicinal and edible plant D. indica were used as experimental materials, and the annual changes of total phenol content and polyphenol oxidase (PPO) activity were analyzed.[Results] pH 7.0 was the optimum value of polyphenol oxidase activity in D. indica plants;the best substrate was catechol with the concentration of 0.15 mol/L;the optimum temperature was 25 ℃.[Conclusions] The total phenol content of D. indica plants was the lowest in April, May and September of each year. The polyphenol oxidase activity of D. indica plants at flowering and fruiting stage was significantly higher than that at pre-flowering stage. 展开更多
关键词 Docynia INDICA polyphenol OXIDASE (PPO) activity total PHENOL content
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Studies on Human Fetal Lens Crystallins Under Oxidative Stress and Protective Effects of Tea Polyphenols 被引量:2
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作者 Hui Xiang, Suhua Pan, Shaozhen LiGuangdong Provincial Corps Hospital, Chinese People’ s Armed Police Forces, Guangzhou 510010, China Zhongshan Ophthalmic Center, Sun Yat-sen University of Medical Sciences, Guangzhou 510060, China 《眼科学报》 1998年第3期170-175,共6页
Purpose: To investigate the oxidative modification of water-soluble crystallins of human fetal lens with H2O2 and fourteen metal ions with or without EDTA. Tea-polyphenols (TP) was added to above solutions in order to... Purpose: To investigate the oxidative modification of water-soluble crystallins of human fetal lens with H2O2 and fourteen metal ions with or without EDTA. Tea-polyphenols (TP) was added to above solutions in order to testing their antioxidative abilities. Methods: The experiments were performed at 37℃ with final concentration of 2.5mg/ml protein, 0.1 mM metal ions, 0.3 mM EDTA and 1.0 mM H2O2. Then the TP was added to the solution with CuSO4 and H2O2, after 5 or 24 hours, the crystallins were analysed with SDS-PAGE and IEF.Results : There were marked oxidative modifications of lens protein in H2O2 and copper without EDTA. In SDS-PAGE patterns, we found an increase in those species above of bands higher than 30 kD and some diffuse bands from 30 to 17 kD after 5 hours. In IEF patterns, there were a general increase on acidity with loss of the more basic species. When the TP was added, there was not any difference with control group.Conclusion: The results indicate that exposure of water-soluble 展开更多
关键词 胎儿 晶状体 晶体蛋白 氧化变性 抗氧化作用 多酚
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Polyphenols, Carotenoids, Vitamin C Content in Tropical Fruits and Vegetables and Impact of Processing Methods
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作者 Emy Njoh Ellong Corinne Billard +1 位作者 Sandra Adenet Katia Rochefort 《Food and Nutrition Sciences》 2015年第3期299-313,共15页
Thirty-five fruits and seventeen vegetables from Martinique were evaluated for total phenol content (TPC), Vitamin C and carotenoid content. TPC, Vitamin C and carotenoid contents ranged from 11.7 to 978.6 mg/100g, 0.... Thirty-five fruits and seventeen vegetables from Martinique were evaluated for total phenol content (TPC), Vitamin C and carotenoid content. TPC, Vitamin C and carotenoid contents ranged from 11.7 to 978.6 mg/100g, 0.1 to 2853.8 mg/100g and 9.7 to 9269.7 μg/100g respectively. Fruits and vegetables from Martinique have equivalent or higher TPC, Vitamin C and carotenoid contents than fruits and vegetables from temperate climates. Cashew apple had high values for all three parameters (55.8 mg/100g of Vitamin C, 603 mg/100g of TPC and 924 μg/100g of carotenoids). Bassignac mango and mamey apple had the highest carotenoid contents, with 3800.3 and 3199.7 μg/100g respectively. Acerola had the highest Vitamin C and polyphenol contents with 2853.8 μg/100g and 727.4 mg/100g respectively. Pigeon peas had high values for all three parameters (569.2 mg/100g of Vitamin C, 978.6 mg/100g of TPC and 364.3 μg/100g of carotenoids). Pumpkin and watercress had the highest carotenoid content, with 9269.7 and 4339 μg/100g respectively. TPC, Vitamin C and carotenoid content were significantly impacted by processing techniques. TPC, Vitamin C and carotenoid contents decreased by up to 75.78%, 100% and 70.18% respectively, depending on the processing technique used. 展开更多
关键词 MARTINIQUE Fruits and VEGETABLES total polyphenols VITAMIN C Carotenoids Technology Process FOOD Composition FOOD Analysis NUTRITIONAL Quality
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EFFECT OF TEA POLYPHENOLS AND EGCG ON NASOPHARYN-GEAL CARCINOMA CELL PROLIFERATION AND THE MECHANISMS INVOLVED
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作者 罗非君 胡智 +5 位作者 邓锡云 赵燕 曾亮 董子刚 易薇 曹亚 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2001年第4期235-242,共8页
Objective: Tea polyphenols present in green tea show cancer chemopreventive effects in many tumor models. Epidemiological studies have also suggested that green tea consumption might be effective in the prevention of ... Objective: Tea polyphenols present in green tea show cancer chemopreventive effects in many tumor models. Epidemiological studies have also suggested that green tea consumption might be effective in the prevention of certain human cancers. In the present study, we investigated the molecular mechanisms of the inhibition of cell proliferation by tea polyphenols in nasopharyngeal carcinoma (NPC) cell line CNE1-LMP1. Methods: CNE1-LMP1 cells were treated with tea polyphenols at various doses (0, 25, 50, 100, 200 μg/ml) for 24 hours, the morphology of cells was observed by light microscopy, and cell survival rate was determined by MTT assay. At the same time, cell cycle of CNE1-LMP1 was analyzed by flow cytometry. Cyclin D1 transcription was analyzed by cyclin D1 promoterluciferase reporter system and expression of cyclin D1 protein by Western blot analysis. Transactivities of NF-κB and AP-1 was analyzed by Dual-fluorescence reporter gene system. Results: After treatment of CNE1-LMP1 cells with tea polyphenols, the number of proliferating cells was obviously decreased as determined by light microscopy and MTT assay (from 100% to 89.4%, 83.3%, 74.8% and 38.1%). With the increase of tea polyphenols concentrations, the number of cells in S-phase was obviously decreased, and the number of cells in G1-phase from 22.20% to 13.16%, and the number of cells in G0/G1 phase was elevated from 68.5% to 74.08%. It suggests that tea polyphenols could arrest the cell cycle at both of the two checkpoints. Furthermore, transcription and were obviously declined 7–8 folds (100–200 μg/ml tea polyphenols or EGCG group) and expression of cyclin D1 protein also decreased in a dose-dependent manner. Transactivities of NF-κB and AP-1 were obviously down-regulated in CNE1-LMP1 cells. Conclusion: Green tea polyphenols could inhibit cell proliferation, by suppressing the activity of NF-κB and AP-1, and by down-regulation of the transcription of cyclin D1. 展开更多
关键词 Nasopharyngeal carcinoma (NPC) Tea polyphenols (tp) NF-κB AP-1 Epstein-Barr virus LMP1 Cyclin D1
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Characterization and Synthesis through Fast Phase-Transfer of Oil-Soluble Double-Coordinated Tea-Polyphenols Arsenic
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作者 Wenfu Zhou Yahong Chen Lin Zhang 《Journal of Biosciences and Medicines》 2014年第5期34-41,共8页
Fast phase-transferring was adopted in ethanol solution at the condition of n (oil-soluble tea pol-yphenol): N (As3﹢) = 2:1, 4:1, 6:1, pH = 4.0, temperature 40&deg;C - 45&deg;C, action period of 15 h to compo... Fast phase-transferring was adopted in ethanol solution at the condition of n (oil-soluble tea pol-yphenol): N (As3﹢) = 2:1, 4:1, 6:1, pH = 4.0, temperature 40&deg;C - 45&deg;C, action period of 15 h to compose the target, of which the productivity was 59%, UV was 267.50, 218.00, 220.50 nm, FTIR was 6291, 34158.6, 2850.2, 1708.2;1457.3;1370.4, 1224.2, 1144.0, 760.5 cm﹣1, fluorescence value λmax = 257, 591.1, 593.7, 590.3, 591.0, 591.5, XRD λ/nm is 3.6974, 4.186, 12.0762, 15.4747, 1H-NMRδ = 0.782, 1.193, 1.483 - 1.586, 1.959 - 2.184, 2.479, 3.116, 3.970 - 3.981, 5.231 - 5.753, 6.537 - 7.300. Finally it was ascertained through XRD as double-coordinated polycrystal compound. 展开更多
关键词 OIL-SOLUBLE Tea-polyphenols (tp) ARSENIC Compound FAST PHASE-TRANSFER Synthesis Characterization
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Optimization of extraction of polyphenols from pomegranate peel by orthogonal experiment design and antioxidant activity
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作者 Hanxin Zhang Junan Zhen +2 位作者 Jiajun Yin Caihong Shi Xiangrong Zhang 《Journal of Polyphenols》 2023年第2期51-59,共9页
The aim of this study was to investigate the extraction process and antioxidant activity of polyphenols from Yunnan Mengzi pomegranate peel.Single factor and orthogonal test were used as optimize the extract rate(ER)o... The aim of this study was to investigate the extraction process and antioxidant activity of polyphenols from Yunnan Mengzi pomegranate peel.Single factor and orthogonal test were used as optimize the extract rate(ER)of polyphenols from pomegranate peel(PGP).The polyphenols antioxidant activity was evaluated by DPPH·,·OH and total reducing ability,and compared with that of Vc.The optimum extraction conditions of polyphenols were as follows:ethanol concentration of 50%,liquid-solid ratio of 50:1,extraction temperature of 90°C,extraction for 4 h.Under these conditions,the ER of polyphenols from GPG was 8.15%.The results showed that the scavenging effects of polyphenols and Vc on DPPH·,·OH increased with increasing concentration,and the scavenging effect of polyphenols on DPPH·was higher than Vc in rang of 0.1-1.6µg/mL.When the concentration is greater than 0.6µg/mL,the scavenging effects of plyphenols on·OH is higher than Vc.The total reducing ability of polyphenols from PGP improved with the increase of concentration,and when the concentration was 8µg/mL,the total reducing ability was 114 U/mL. 展开更多
关键词 pomeranate peel total polyphenols extraction process orthogonal experiment antioxidant activity
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茶多酚(TP)对家禽免疫功能的研究 被引量:40
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作者 詹勇 李进昌 杨贤强 《浙江农业大学学报》 CSCD 1992年第4期74-76,共3页
选用14日龄健康的海佩科内用仔鸡48羽,随机分成试验(24羽)和对照(24羽)两组.试验组在饲粮中添加0.25%的茶多酚(TP),研究TP对鸡免疫功能的作用.试验结果表明,TP对自然感染法氏囊病鸡,有明显提高(p<0.05)鸡血液中红细胞C_(3b)受体和... 选用14日龄健康的海佩科内用仔鸡48羽,随机分成试验(24羽)和对照(24羽)两组.试验组在饲粮中添加0.25%的茶多酚(TP),研究TP对鸡免疫功能的作用.试验结果表明,TP对自然感染法氏囊病鸡,有明显提高(p<0.05)鸡血液中红细胞C_(3b)受体和免疫复合物的含量及保护鸡脾脏正常的免疫功能,同时也发现TP对公母鸡法氏囊的重量有不同影响.本试验表明,TP具有提高家禽免疫功能的作用. 展开更多
关键词 茶多酚 免疫功能 家禽
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浅水湖泊TP分布的迎风有限元数值模型研究 被引量:3
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作者 马生伟 蔡启铭 《环境科学研究》 EI CAS CSCD 北大核心 1999年第5期56-59,共4页
从控制方程出发,以Galerkin有限元法为基础,结合有限元法的较新改进,推导、建立了一个适合于浅水湖泊TP浓度分布计算的二维迎风有限元的数值模型,并将其应用于太湖。
关键词 总磷 数值模拟 迎风有限元法 太湖 湖泊污染
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榅桲总多酚的纯化工艺及PTP1B抑制作用研究 被引量:4
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作者 哈及尼沙 阿力木江.阿布力孜 +1 位作者 阿米娜 阿吉艾克拜尔.艾萨 《天然产物研究与开发》 CAS CSCD 北大核心 2015年第8期1448-1452,1384,共6页
通过采用11种大孔吸附树脂对榅桲多酚粗提物的静态吸附和解吸试验,筛选出适合分离纯化榅桲总多酚的最优树脂,并对其动态吸附特性和影响因素进行研究。结果表明:最佳纯化工艺条件为:AB-8大孔吸附树脂做吸附填料,上样液质量浓度0.04 g/m L... 通过采用11种大孔吸附树脂对榅桲多酚粗提物的静态吸附和解吸试验,筛选出适合分离纯化榅桲总多酚的最优树脂,并对其动态吸附特性和影响因素进行研究。结果表明:最佳纯化工艺条件为:AB-8大孔吸附树脂做吸附填料,上样液质量浓度0.04 g/m L,以2 BV/h的吸附速率进行吸附,上样量为11 BV,用3 BV蒸馏水除杂后,以50%乙醇溶液为洗脱剂,洗脱液用量为4 BV,洗脱流速控制在2 BV/h。经AB-8树脂吸附富集后,样品总多酚质量浓度达到了30.11 mg/g,是粗提物(9.55 mg/g)的3倍。对纯化前后的榅桲总多酚进行PTP1B的抑制作用研究,结果显示,榅桲总多酚对PTP1B有较强的抑制作用,即榅桲总多酚纯化前的IC50为78.14μg/m L,用AB-8树脂纯化后所得总多酚的IC50为16.12μg/m L。 展开更多
关键词 榅桲 AB-8大孔吸附树脂 总多酚 纯化 Ptp1B抑制作用
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LAS对人工快滤系统去除TP的影响
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作者 郭伟 李培军 +1 位作者 李建东 赵天宏 《环境科学与技术》 CAS CSCD 北大核心 2009年第8期31-33,共3页
文章运用人工土柱模拟的方法来研究LAS对人工快滤系统去除TP的影响。研究结果表明,随着污水中LAS浓度(≤100mg/L)的增加,人工快滤系统对TP的去除率表现为逐渐下降。TP的去除率大小为处理Ⅰ>处理Ⅱ>处理Ⅲ>处理Ⅳ。在延长干化... 文章运用人工土柱模拟的方法来研究LAS对人工快滤系统去除TP的影响。研究结果表明,随着污水中LAS浓度(≤100mg/L)的增加,人工快滤系统对TP的去除率表现为逐渐下降。TP的去除率大小为处理Ⅰ>处理Ⅱ>处理Ⅲ>处理Ⅳ。在延长干化时间条件下,TP的去除率增大,并且LAS浓度越大效果越明显。LAS对人工快滤系统中TP的去除有着显著的影响;但合理地控制工艺参数能够实现LAS和TP的有效去除。 展开更多
关键词 人工快速渗滤系统 直链烷基苯磺酸盐 总磷
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茶多酚(TP)与皮肤病治疗的研究进展 被引量:9
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作者 张双双 方芳 《复旦学报(医学版)》 CAS CSCD 北大核心 2015年第2期273-278,共6页
绿茶是一种日常饮料,其中的茶多酚(tea polyphenols,TP)为有效活性成分。TP取材于纯天然绿色植物,成本低廉且易得,不良反应小。研究发现,TP有抗衰老、抗辐射、抗氧化、抗肿瘤、美容保健等多方面作用,可显著改善皮肤病的病理损伤,因此认... 绿茶是一种日常饮料,其中的茶多酚(tea polyphenols,TP)为有效活性成分。TP取材于纯天然绿色植物,成本低廉且易得,不良反应小。研究发现,TP有抗衰老、抗辐射、抗氧化、抗肿瘤、美容保健等多方面作用,可显著改善皮肤病的病理损伤,因此认为TP在皮肤病治疗方面有广泛的应用前景和研究价值。 展开更多
关键词 绿茶 茶多酚(tp) 皮肤病 治疗
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Determination of Residual Catechins, Polyphenolic Contents and Antioxidant Activities of Developed Theaflavin-3,3’-Digallate Rich Black Teas 被引量:5
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作者 Samuel Kimutai John Wanyoko +3 位作者 Thomas Kinyanjui Stephen Karori Augustine Muthiani Francis Wachira 《Food and Nutrition Sciences》 2016年第3期180-191,共12页
This study was carried out to characterize total residual catechins and their fractions, polyphenolic contents and antioxidant activities of black teas enriched with high levels of theaflavin-3,3’-digallate. The made... This study was carried out to characterize total residual catechins and their fractions, polyphenolic contents and antioxidant activities of black teas enriched with high levels of theaflavin-3,3’-digallate. The made teas were processed from eleven selected cultivars. A comparative study was carried out between the processed teas and those from commercially grown Kenyan cultivars in relation to the above chemical parameters. A correlation matrix analysis was also conducted to find out whether a relationship existed between the antioxidant activities and the said chemical parameters. The total residual catechins were found to range between 3.10% and 8.08%. The total polyphenol levels varied between 19.00% and 28.90%, while the antioxidant activities of the teas ranged from 82.70% to 91.70%. There was a significant p < 0.001 correlation between the antioxidant activity and total polyphenols (r = 0.8948). There was also a high correlation p < 0.001 between the antioxidant activity and total catechins (r = 0.8878). Out of the four catechin fractions, the antioxidant activity correlated most with EGCG (r = 0.8774). The total polyphenolic contents and antioxidant activities for most of the cultivars were comparable to those of the green tea reference standard. From the figures obtained, it can be concluded that the most of the newly developed black teas of the selected cultivars have higher quality and enhanced antioxidant activities and that they can be recommended for commercial production. 展开更多
关键词 total polyphenols Antioxidant Activity Residual Catechins THEAFLAVINS
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TPS based on trilateration for the feed measurement of FAST 被引量:1
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作者 袁卉 Zhu Lichun 《High Technology Letters》 EI CAS 2018年第1期90-94,共5页
Five-hundred-meter Aperture Spherical radio Telescope( FAST) is the largest sensitive single dish radio telescope in the world,in which the control and measurement of the feed is one crucial section of the FAST contro... Five-hundred-meter Aperture Spherical radio Telescope( FAST) is the largest sensitive single dish radio telescope in the world,in which the control and measurement of the feed is one crucial section of the FAST control system. Trilateration is presented to obtain three-dimensional coordinate for tracking feed focus cabin. Every three total stations chase prism movement to be attached on feed focus cabin and the prism position is determined from the measured distances based on the principle of trilateration. Therefore,feed position is determined from three prisms on the focus cabin. This study is to assess the accuracy and reliability of trilateration calculation on tracking focus cabin of FAST. Different arrangement of total stations on trilateration is theoretically studied. Through experiment,the proposed method shows that the accuracy is better than that of the polar coordinate measurement. The average root mean square error is lower than 0. 6 mm,which is found to have high accuracy and reliability. 展开更多
关键词 Five-hundred-meter Aperture Spherical radio Telescope (FAST) TRILATERATION FEED measurement total STATION prism system(tpS) arrangement of total STATION
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Study on Colorimetric Method and Content Determination of Total Phenol in Homemade Plum Wine 被引量:2
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作者 Yun TENG Pei QUN +1 位作者 Xue ZHAI Yuan LIU 《Medicinal Plant》 2017年第1期22-26,共5页
[Objectives] To study on colorimetric method and content determination of total phenol in homemade plum wine. [Methods]The optimal determination condition of total polyphenols content in plum wine( commercially availa... [Objectives] To study on colorimetric method and content determination of total phenol in homemade plum wine. [Methods]The optimal determination condition of total polyphenols content in plum wine( commercially available and homemade) by Folin-Ciocalteu method was inspected,and commercially available and homemade plum wine was evaluated by the method. [Results]The optimal determination conditions of total polyphenols content: sample dose of 1. 0 m L,Folin-Ciocalteu reagent of 1 m L,4% Na_2CO_3 solution of 4. 0 m L,reaction temperature of 50 ℃,reaction time of 1. 5 h,and determination wavelength of 756 nm. Absorbance showed good linear relationship with total polyphenols content within the range of 17. 73-59. 12 μg/m L( y = 14. 878 x + 0. 0739,R^2= 0. 9998). Recovery rate of adding standard sample was between 98. 8% and 103. 5%,and relative standard deviation was 2. 0%( n = 5). [Conclusions]The method had high precision degree and good stability,which was suitable for measuring total polyphenols content in plum wine( commercially available and homemade). 展开更多
关键词 PLUM wine(commercially available and homemade) FOLIN-CIOCALTEU SPECTROPHOTOMETRIC method total polyphenols Content determination
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冠状动脉侧支循环及PCI治疗对CTO患者Tp-e间期、Tp-e/QT比值的影响 被引量:1
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作者 罗进 王延博 +1 位作者 刘鹏 贺琳 《岭南心血管病杂志》 CAS 2022年第5期397-402,共6页
目的探讨冠状动脉侧支循环(coronary collateral circulation,CCC)对冠状动脉慢性完全闭塞病变(chronic total coronary occlusion,CTO)患者Tp-e间期、Tp-e/QT比值的影响,以及经皮冠状动脉介入(percutane⁃ous coronary intervention,PCI... 目的探讨冠状动脉侧支循环(coronary collateral circulation,CCC)对冠状动脉慢性完全闭塞病变(chronic total coronary occlusion,CTO)患者Tp-e间期、Tp-e/QT比值的影响,以及经皮冠状动脉介入(percutane⁃ous coronary intervention,PCI)治疗对CTO患者Tp-e间期、Tp-e/QT比值的影响及临床意义。方法本研究选取邵阳市中心医院心内科2018年7月至2020年12月期间CTO患者共150例。CCC采用Rentrop评分进行分级,将入选患者分为CCC不良组(Rentrop 0级、1级组),CCC良好组(Rentrop 2级、3级组)。测量各组患者心电图中Tp-e间期、Tp-e/QT比值。另从以上研究对象中按是否成功行PCI治疗分为PCI治疗成功组及PCI治疗失败组。观察两组患者PCI治疗前及治疗后心电图中Tp-e间期、Tp-e/QT比值的情况。结果CCC良好组患者Tp-e间期、Tp-e/QT比值低于CCC不良组,差异有统计学意义(P<0.05)。PCI治疗成功组与PCI治疗失败组患者术前临床资料及Tp-e间期、Tp-e/QT比值比较,差异有统计学意义(P<0.05)。PCI治疗成功组患者术后Tp-e间期、Tp-e/QT比值较术前下降,差异有统计学意义(P<0.05)。PCI治疗成功组患者术后Tp-e间期、Tp-e/QT比值低于PCI治疗失败组,差异有统计学意义(P<0.05)。结论CTO患者中,良好的侧支循环形成有利于降低心室跨壁复极离散度指标Tp-e间期、Tp-e/QT比值,更好地恢复CTO患者心肌细胞电生理稳定性;成功的PCI治疗可以减少CTO患者心室复极离散度指标Tp-e间期、Tp-e/QT比值,从而降低室性心律失常发生的风险。 展开更多
关键词 冠状动脉侧支循环 冠状动脉慢性完全闭塞病变 经皮冠状动脉介入治疗 tp-E间期 tp-e/QT比值
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Measuring Quality of Economic Growth Incorporating Environment and Social Welfare:a Total Productivity Approach with an Application on China
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作者 SUN Yanyan DAI Changjun 《Journal of Donghua University(English Edition)》 EI CAS 2018年第5期411-417,共7页
By extending the traditional productivity theory,a new concept total productivity( TP) is introduced. Using a directional distance function approach,the concept is applied to measuring economic growth of 8 economic re... By extending the traditional productivity theory,a new concept total productivity( TP) is introduced. Using a directional distance function approach,the concept is applied to measuring economic growth of 8 economic regions of China covering an 18 years period( 1997—2014) and test its convergence. Results showed that TP grew at an average rate of 6. 6% per year led mainly by technical change( 6. 5%). When environmental undesirable outputs are included,the Middle Yellow River,Northwest and Southwest regions of China witnessed higher productivity changes. Results of the convergence analysis revealed that China had made progress in reducing regional imbalance in growth. Inclusion of undesirable output showed that the energy-saving emission reduction policies had speed up the convergence rate of TP and environment oriented productivity. However,China's welfare oriented productivity is still very low. 展开更多
关键词 undesirable OUtpUT directional DISTANCE function total productivity(tp) Malmquist-Luenberger PRODUCTIVITY index quality of ECONOMIC growth
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