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以绿茶为研究对象,采用复合酶(纤维素酶和果胶酶质量比1︰1)辅助提取绿茶中茶多酚,在单因素的基础上,选择酶添加量、酶解温度、pH、乙醇浓度为影响因子,运用响应面法进行四因素三水平试验设计,研究各因素对绿茶茶多酚得率的影响,以及绿茶茶多酚的抑菌性。结果表明:响应面试验绿茶茶多酚提取的最佳工艺参数为酶添加量2.0mL,酶解温度48℃,pH4.8,乙醇浓度50%,在该条件下绿茶茶多酚得率为24.59%,接近预测值24.68%。绿茶茶多酚浓度与抑菌效果成正相关,当绿茶茶多酚浓度为1×10^-2mg/mL时,绿茶茶多酚对枯草芽孢杆菌和大肠杆菌效果较显著,抑菌率分别为46.01%和45.77%,而对金黄色葡萄球菌抑制效果不显著。 相似文献
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研究了漆树酶水溶液、生漆丙酮粉末和两种固定化漆树酶(聚丙烯酰胺包埋漆树酶和ABSE-交联琼脂共价偶联漆树酶)对绿茶中茶多酚的催化氧化反应。它们都能催化部分茶多酚氧化。但在固定化漆树酶催化下茶多酚的氧化初速度和最终转化率最高。固定化漆树酶在催化茶多酚氧化时可以重复使用。 相似文献
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超声波辅助提取竹叶茶多酚工艺研究 总被引：1，自引：0，他引：1
以竹叶为原料，采用超声波辅助提取茶多酚，通过单因素实验和正交试验优化提取条件。结果表明，从竹叶中提取茶多酚的最佳条件为：乙醇浓度60％、料液比1：10、温度65℃、提取时间30min、超声波功率320W，此条件下茶多酚得率为1．78％。 相似文献
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《林产化学与工业》2017,(5)
以红茶茶多酚和绿茶茶多酚为原料,利用同步热分析(TGA/DSC)、红外光谱分析(FT-IR)和质谱分析(MS)联用技术观测其热解过程中质量变化及产生的气相产物,同时对不同热处理温度下固相残留物的化学组成进行表征,分析茶多酚热解反应机理。结果表明:茶多酚为富含侧链结构的芳香族化合物,主要由C、H、O和微量N元素构成。温度低于200℃时,茶多酚的热失重基本源于所含自由水和结合水的蒸发;热解反应起于200℃附近,取决于其侧链结构的稳定性;在200~350℃间发生剧烈热分解反应,侧链结构出现断裂和重组,生成H2O和CO2为主的气相产物;在350~800℃温度区间,热解反应变得缓慢而持久,反映了残留物向稳定的稠环芳烃结构转变的机制。建立起的认识为茶多酚有效利用和开拓防火领域应用前景提供指南。 相似文献
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《Fitoterapia》2013
Pistachio (Pistacia vera L.) nuts are a rich source of phenolic compounds, known for their high antioxidant activity, and contained not only in the seeds but also in the skin. A pistachio cultivar of high quality is typical of Bronte, Sicily, Italy. The purpose of our study was to investigate the chemical composition and antioxidant properties of two polyphenol-rich extracts from skins (TP) and decorticated seeds (SP) of Bronte pistachios, and to verify the potential use of these extracts for topical photoprotective products.Chemical analysis showed that the TP and SP extracts contain high levels of phenolic compounds, but the TP extract is about ten times richer in phenols than the SP extract, being anthocyanins the most abundant compounds found in the TP extract. Both these extracts, and especially the TP extract, possess good radical scavenger/antioxidant properties, as shown in a series of in vitro assays carried out using homogenous and non-homogenous chemical environment. Furthermore both the TP extract and, although at a lower degree, the SP extract reduce, when topically applied, UV-B-induced skin erythema in human volunteers. These findings suggest that extracts from Bronte TP and SP could be successfully employed as photoprotective ingredients in topical cosmetic and pharmaceutical formulations. 相似文献
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To assess the impact of conversion of native forests to monocultural larch plantations on soil chemical properties, we compared the total and various fractions of soil phosphorus (P) and acid phosphatase activity (APA) between natural secondary forests (NSF) and Larix olgensis plantations (LOP) on a montane forest site in eastern Liaoning Province, Northeast China. We found that the concentrations of total P (TP), inorganic P, and iron-bound P (Fe-P) were significantly higher, and the concentrations of microbial biomass P (MBP), sodium bicarbonate-extractable organic P (NaHCO3-Po), and APA were significantly lower, in the LOP stands than in the NSF stands; whilst organic P, sodium bicarbonate-extractable inorganic P (NaHCO3-Pi), aluminum-bound P (Al-P) and calcium-bound P (Ca-P) were comparable between the two forest types. Our study also showed that the ratios of MBP/TP, NaHCO3-Pi/TP, NaHCO3-Po/TP, and APA significantly varied with time during the growing season. Moreover, the concentrations of NaHCO3-Pi, NaHCO3-Po, and MBP had significant (P < 0.01) and positive linear relationships with APA. Overall, results from this study suggest that conversion of native forests to larch plantations in the region is more likely to cause compositional change in soil P than to result in reduction in overall P availability. 相似文献
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《林业研究》2020,31(5)
In this study, we investigated the effects of environmental factors on plant phenolic variability, seasonal dynamics of total phenolic content(TP),extractable condensed tannins(ECT), protein-bound condensed tannins(PBCT), fiber-bound condensed tannins(FBCT), total condensed tannins(TCT), protein precipitation capacity(PPC) and nutrient content in the branchlets and fine roots of Casuarina equisetifolia. TP and TCT concentrations in branchlets were lowest in the spring, then increased in summer and autumn, similar to the seasonal dynamics in air temperature. TP and TCT concentrations in fine roots were highest in summer, coinciding with heavy precipitation. In general, TP and TCT concentrations were higher in branchlets than in fine roots. No significant difference was found in C concentration among various seasons for either branchlets or fine roots. Branchlets had significantly higher N and P concentrations than fine roots in most seasons. The C/N and N/P ratios in branchlets were significantly lower than in fine roots in all seasons, except summer. The relationship between branchlets and fine roots was significant for C, P and FBCT, but no significant relationships were found for N, TP, ECT, PBCT and TCT.Additionally, TP and TCT content were each significantly correlated with PPC in branchlets and in fine roots. Both TP/N and TCT/N ratios were highest in the autumn for the branchlets and in the summer for fine roots. The results indicate that high temperatures lead to increased tannin production in branchlets, but that the tannin content in fine roots is mainly affected by precipitation. Tannin content was greater in branchlets than in fine roots, which may indicate that selective pressure is greater on branchlets than on fine roots. 相似文献
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在野外调查的基础上,选取小黑三棱+杉叶藻+荇菜、水葱+睡菜+荇菜、菰+荸荠+荇菜和香蒲+睡菜+眼子菜等4种云南高原常见湖滨湿地植物群落作为试验材料在净化槽中进行水质净化模拟研究。结果表明,4种湿地植物群落对生活污水TP(总磷)和COD(化学需氧量)都有较好的净化效果,各植物群落对TP和COD的去除率均显著高于无植物对照组(P<0.05);但不同群落之间净化效果存在较大的差异性,水葱+睡菜+荇菜群落对TP去除效果显著优于其他3种群落(P<0.05),去除率达到94.72%,与该群落挺水植物水葱的生长特性密切相关;植物群落能有效促进湿地对污染物的去除效果,各群落对TP和COD去除的贡献率分别为32.73%～49.63%和14.76%～20.46%;湿地运行过程中,COD的去除效果存在不稳性和波动性。在湖滨带的恢复与重建过程中,适当增加挺水植物的比例,能有效促进湿地对TP和COD的净化效果。 相似文献
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Mei Xue Zhen-zhou Jiang Ji-ping Liu Lu-Yong Zhang Tao Wang Hao Wang Li Liu Zhi-xing Zhou 《Fitoterapia》2010,81(8):1109-1112
Tripterygium Glycosides (TG) is effective in the treatment of patients with a variety of inflammatory and autoimmune diseases, especially rheumatoid arthritis (RA) in clinical. Wilforlide A (T1) serves as a quality control standard of TG that be listed in Drug Standard of Ministry of Public Health of the People's Republic of China. The pharmacologic actions of T1 remain to be unidentified. In this paper, we studied the anti-inflammatory and immune suppressive effect of T1, and compared it with Triptolide (TP), which believed to be the major active component of TG. Carrageenan-induced rat pedal swelling, tampon-induced rat granulation, and mice ear inhibition rate of swelling trail results show that high-dose T1 has obvious anti-inflammatory effect. Colorimetric detection contents of hemolysin, carbon elimination from plasma of mice, mice delayed hypersensitivity immune, and organ index were measured. The results show that T1 has no significant immune suppressive activity, and there has a significant difference with TP and TG. Therefore, we think the content of TP also should be controlled as a supplement standard in order to ensure safe and effective medication. 相似文献
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Mature leaves of trees and shrubs from sub-humid tropical regions of Benin (Acioa barteri, Cassia sieberiana, Dialium guineense, Dichrostachys cinerea, Guiera senegalensis, Milletia thonningii, Piliostigma reticulatum) and arid and semiarid regions of Zimbabwe and Niger (Acacia holosericea, A. nilotica, Dichrostachys cinerea, Securidaca longepedunculata, Parinari cuvetelio, Ziziphus mucronata) in Africa, and from sub-tropical region in foot-hills of North-West Humid Himalayan range (Albizia stipulata, Bauhenia variegata, Cedrela toona, Celtis australis, Dendrocalamus hamiltonii, Grewia optiva, Leucocephala leucocephala, Morus alba, Papulus ciliata, Quercus incana, Q. semecarpifolia, Q. glauca, Q. serrata, Q. ilex, Robinia pseudoacacia, Salix tetrasperma) were analysed for crude protein, total phenols (TP), protein precipitation capacity (PPC) and operational activity of tannins (values are as mean ± SE). There was no significant difference in the crude protein values of forages obtained from the Himalayan and African region (15.2 ± 1.16 and 14.1 ± 1.19%, respectively), however the levels of TP and biological value of tannins as PPC were significantly higher for the African forages (TP 15.7 ± 4.27 vs 6.0 ± 1.0%; PPC 327.2 ± 113.6 vs 56 ± 15.9 mg bovine serum albumin precipitated/g). The operational activity of tannins expressed as mg protein precipitated per unit of phenols was also significantly higher in forages from the African regions (1.97 ± 0.47 vs 0.66 ± 0.17). For a small set of leaves from arid and semiarid zones of Middle East (Syria, A. cyanophylla; Israel, A. saligna) and India (Eugenia jambolana, Eucalyptus punctata, Prosopis cineraria and Shorea robusta) TP, PPC and tannin activity were closer to those for the African forages.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
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选择4种人工林,包括3个乡土树种(阔叶合欢(Albizia lebbeck)、黄豆树(A.procera)、柚木(Tectona grandis))和一个乡土草种(印度实竹(Dendrocalamus strictus))的高密度人工幼林,研究了人工林发育早期阶段对印度Singrauli煤矿废弃地土壤养分的影响。在4种人工林4年生和5年生阶段,采集0-10、10-20cm层土壤,分析其总有机碳、全氮和全磷含量。结果表明,林龄、树种和土层对土壤总有机碳、全氮和全磷含量的影响存在显著差异;各林分10-20cm土层中的全总有机碳、全氮和全磷含量较低;4个不同林分对土壤养分的改良效果表现为:阔叶合欢>印度实竹>黄豆树>柚木。说明人工林对煤矿废弃地土壤的改良效果因树种而异。 相似文献
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在大兴安岭选择典型的干旱阳坡草丛和灌草丛植被,采用样线法研究植被类型间和地形部位间土壤水分、养分的空间分异特征。结果表明,草丛、灌草丛和山脊林地间土壤水分（SM）和养分（全碳（TC）、全磷（TP）、碱解氮（AN）、速效磷（AP）、速效钾（AK）、碳氮比（C/N））差异显著,均表现为山脊林地〉灌草丛〉草丛的格局;草丛和灌草丛不同地形部位土壤水分和养分（SM、TC、TP、AP、AK、和C/N）最大值均出现在山脊林地,但是在草丛坡下土壤水分和养分（SM、TC、TP、全钾（TK）和AP）高于坡上和坡中,而在灌草丛坡上土壤养分（TC、全氮（TN）、TP、AN、AP、AK和C/N）高于坡下和坡中。通过本研究得知,草丛和灌草丛土壤水分与磷素的缺乏是植被恢复的重要限制,地形和人为干扰改变了不同地形部位间土壤的水分和养分特征。 相似文献
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The protective effects of Ginkgoselect Phytosome((R)) (GBP) on Rifampicin (RMP) induced hepatotoxicity and the probable mechanism(s) involved in this protection were investigated in rats. Liver damage was induced in Wistar rats by administering rifampicin (500 mg/kg, p.o.) daily for 30 days. Simultaneously, GBP at 25 mg/kg and 50 mg/kg, and the reference drug silymarin (100 mg/kg) were administered orally for 30 days/daily to RMP treated rats. Levels of marker enzymes (SGOT, SGPT and SALP), albaumin (Alb) and total proteins (TP) were assessed in serum. The effects of GBP on lipid peroxidation (LPO), reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione reductase (GR) were assayed in liver homogenates to evaluate antioxidant activity. GBP (25 and 50 mg/kg) and silymarin elicited a significant hepatoprotective activity by lowering the levels of serum marker enzymes and lipid peroxidation and elevated the levels of GSH, SOD, CAT, GPX, GR, Alb and TP in a dose dependant manner. The present findings suggest that the hepatoprotective effect of GBP in RMP induced oxidative damage may be related to its antioxidant and free radical scavenging activity. 相似文献