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1.
用红外指纹光谱的聚类分析法对女贞属的植物来源进行生药学鉴定。此法利用红外指纹图谱确定贵州多个产地的苦丁茶的原植物来源是女贞属植物粗壮女贞。本方法具有方便、可靠,重复性好的特点,可用于苦丁茶的生药学鉴别。  相似文献   

2.
女贞苦丁茶挥发油成分分析   总被引:13,自引:0,他引:13  
苦丁茶是我国南方各民族长期饮用的茶代用品之一,其基原植物种类较多,据调查苦丁茶原植物有9科15种植物,其中木犀科(Oleaceae)女贞属(Ligustrum L.)有粗壮女贞[L. robustum (Roxb.) Bl.]、紫茎女贞(L. purpurascens Y.C.Yang)、序梗女贞(L. pedunculare Rehd)、日本毛女贞(L. japonicum Thunb. var. pubescens Koidz.)等[1~8].  相似文献   

3.
女贞子化学成分的研究   总被引:9,自引:0,他引:9  
从女贞属植物女贞(LigustrumlucidumAit.)的果实中分离鉴定了7个化合物,其中Ⅰ~Ⅵ系从该属植物中首次分离得到的已知化合物;化合物Ⅶ是新化合物,经光谱分析和化学定性反应确定了其结构,并命名为女贞酸。  相似文献   

4.
中国冬青属苦丁茶名实辨证   总被引:15,自引:0,他引:15  
通过对冬青科饮料植物苦丁茶的考证,将苦丁茶IlexkudingchaC.J.Tseng并入扣树I.kaushueS.Y.Hu中,对新种五棱苦丁茶I.pentagonaS.K.Chen,Y.X.FengetC.F.Liang作了描述,并提供了4个相近种的检索表  相似文献   

5.
采集自贵州的两个稀有虫草   总被引:3,自引:0,他引:3  
刘作易  梁宗琦 《菌物系统》1997,16(2):97-101
1994年6月采集自贵州梵净山和荔波茂兰保护区的虫草属真菌,中国新记录种-螳螂虫草(Cordycepsmantidaecolakob.etShim.)和属于蛇形虫草亚属头状组的一新种-贵州虫草(CordycepsguizhouensisLiu,LiangetLiusp.nov)贵州虫草寄生于刺蛾茧上,茧表面褐色,椭圆形,大小为4~6×5~9mm,在一个茧上可长1~2根子座,子座单生,不分枝,圆柱形  相似文献   

6.
王筱英 《植物研究》1994,14(4):353-357
贵州的石杉属植物王筱英摘要*本文介绍贵州产的9种石杉,内含1新种,即雷山石杉HuperzialeishanensisX.Y.Wang;同时还编有分种检索表、生境和地理分布。关键词石杉属,贵州NOTESONHUPERZIABERNH.INGUIZHOU...  相似文献   

7.
贵州苦丁茶——粗壮女贞罗军英在贵州有一种常绿灌木,用其幼芽、嫩叶、嫩枝制的茶叶,当地叫“苦丁茶”。它喝后爽口,解油腻,生津止渴,有较强的解暑、清热功能以及祛风、消炎等医疗保健作用,是贵州人喜欢的一种传统饮料。它还含有丰富的硒,是非常理想的天然药用保健...  相似文献   

8.
黄勃  樊美珍 《菌物系统》1998,17(3):193-194,198
本文报道采自贵州的中国新记录属层束梗孢属Hymenostilbe一新种刺孢层束梗孢(Hymenostilbespiculatasp.nov.Huan,FanetLi)该种寄生于蜘蛛,产孢细胞子实层状复被于孢梗束上,无瘤,多点芽茁产孢,分生孢子单生,光滑或具细刺,5.6~6.6×1.3~2.7μm。  相似文献   

9.
红豆杉科植物RAPD分析及其系统学意义   总被引:23,自引:2,他引:21  
王艇  黄超 《西北植物学报》2000,20(2):243-249
利用随机扩增多态性DNA(RAPD)技术分析了红豆杉科(Taxaceae)红豆杉属(Taxus)、白豆杉属(Pseudotaxus)、穗花杉属(Amentotaxus)和榧树属(Torreya)的6种植物:红豆杉(Taxus chinensis (Pilger)Rehd)、南方红豆杉(Taxus chinensis var.mairei(Lemee etLevl.)Cheng etMaireYew  相似文献   

10.
贵州凤冈兰多维列世晚期管状体及其古植物学意义   总被引:1,自引:1,他引:0  
贵州凤冈县硐卡拉韩家店组顶部保存有很好的管状体化石,经研究计有3属6种。依据生物地层学的综合证据,确认其时代为兰多维列世晚期。介于散生管的壁上出现了具缘纹孔这一重要特征,判断在早志留世已确有早期维管植物的存在;从内部结构方面,论证了Pinnatiramosus qianensis Geng属于早期维管植物。  相似文献   

11.
Tea catechins and other flavonoids have been shown to potentially protect against chronic cardiovascular diseases such as coronary heart disease and atherosclerosis. In this study, 6-month-old female Sprague-Dawley rats were fed green tea extract (50 mg/100 ml in drinking water) up to the age of 22 months, and the age-associated changes in Maillard-type fluorescence and carbonyl groups in the aortic and skin collagen were compared with those occurring in the water-fed control animals. Collagen-linked Maillard-type fluorescence was found to increase in both the aortic and skin tissues as animals aged. The age-associated increase in the fluorescence in the aortic collagen was remarkably inhibited by the green tea extract treatment, while that occurring in the skin collagen was not significantly inhibited by the treatment. The collagen carbonyl content also increased in both the aortic and skin tissues as animals aged. In contrast with the case of Maillard-type fluorescence, however, the age-associated increase in the carbonyl content was not inhibited by the green tea extract treatment either in the aortic or skin collagen. These results suggest that the inhibition of AGE formation in collagen is an important mechanism for the protective effects of tea catechins against cardiovascular diseases.  相似文献   

12.
Tea is one of the most widely consumed beverages, second only to water. Many experimental researches in laboratory animals demonstrated that tea components had an inhibitory effect on carcinogenesis at a number of organ sites. The inhibitory effects of tea against carcinogenesis have been attributed to the biologic activities of the polyphenol fraction in tea. This review summarizes experimental data on chemopreventive effects of tea polyphenols in various tumor bioassay systems. Many laboratory studies have demonstrated the inhibitory effects of green tea polyphenols, especially (-)-epigallocatechin-3-gallate (EGCG), on carcinogenesis in animals models. The majority of these studies have been conducted in mouse skin tumor models, where tea polyphenols were used either as oral feeding in drinking water or in direct local application. Most studies used 12-O-tetradecanoylphorbol-13-acetate (TPA) or ultraviolet (UV) radiation as the tumor promoter and found anticarcinogenic effects caused by green tea polyphenols. Black tea was also found to be effective, although the activity was weaker than that of green tea in some experiments. Other studies showed that black tea polyphenols-theaflavins exhibited stronger anticarcinogenic activity than did EGCG. Caffeine in tea was also important for tea to prevent tumorigenesis. The molecular mechanisms of the cancer chemopreventive effects of tea polyphenols are not completely understood. They are most likely related to the mechanisms of biochemical actions of tea polyphenols, which include antioxidative activities, modulation of xenobiotic metabolite enzymes and inhibition of tumor promotion. In addition, we have also proposed that tea polyphenols function as cancer chemopreventive agents through modulation of mitotic signal transduction. However, the molecular mechanisms involved in this modulation need further investigation.  相似文献   

13.
低农药残留量的乌龙茶种质资源筛选研究   总被引:2,自引:0,他引:2  
以福建省武夷山茶叶科学研究所鸟龙茶种质资源圃120份资源为试验材料,依外部形态特征初步筛选出31份比较有希望的品种(系)。将联苯菊酯、甲氰菊酯、氯氰菊酯和噻嗪酮4种农药喷施于这31份资源,7d后采摘鲜叶,烘干固样。用气相色谱法分析检测31份品种(系)鲜叶中4种农药的残留量,筛选出低联苯菊酯、低甲氰菊酯、低氯氰菊酯和低噻嗪酮残留量的乌龙茶特异资源各5、4、3和7份。  相似文献   

14.
Tea green leafhopper is one of the most damaging tea pests in main tea production regions of East Asia. For lack of recognized morphological characters, the dominant species of tea green leafhoppers in Mainland China, Taiwan and Japan have always been named as Empoasca vitis Göthe, Jacobiasca formosana Paoli and Empoasca onukii MATSUDA, respectively. Furthermore, nothing is known about the genetic relationships among them. In this study, we collected six populations from Mainland China, four populations from Japan and one population from Taiwan, and examined the genetic distances in the COI and 16sRNA regions of mtDNA among them. The results showed that the genetic distances based on single gene or the combined sequences among eleven leafhopper populations were 0.3–1.2%, which were all less than the species boundary of 2%. Moreover, there were at least two haplotypes shared by two distinct populations from different regions. The phylogenetic analysis based on single gene or combined sets also supported that tea green leafhoppers from Mainland China, Taiwan and Japan were closely related to each other, and there were at least two specimens from different regions clustered ahead of those from the same region. Therefore, we propose that the view of recognizing the dominant species of tea green leafhoppers in three adjacent tea production regions of East Asia as different species is unreliable or questionable and suggest that they are a single species.  相似文献   

15.
Tea is the most popular beverage, consumed by over two thirds of the world's population. Tea is processed differently in different parts of the world to give green (20%), black (78%) or oolong tea (2%). Green tea is consumed mostly in Japan and China. The antimutagenic and anticarcinogenic activities of green tea are extensively examined. The chemical components of green and black tea are polyphenols, which include EC, ECG, EGC, EGCG and TFs. This article reviews the epidemiological and experimental studies on the antimutagenicity and anticarcinogenicity of tea extracts and tea polyphenols. In Japan, an epidemiological study showed an inverse relationship between habitual green tea drinking and the standardized mortality rates for cancer. Some cohort studies on Chanoyu (Japanese tea ceremony) women teachers also showed that their mortality ratio including deaths caused by malignant neoplasms were surprisingly low. The antimutagenic activity against various mutagens of tea extracts and polyphenols including ECG and EGCG has been demonstrated in microbial systems (Salmonella typhimurium and Escherichia coli), mammalian cell systems and in vivo animal tests. The anticarcinogenic activity of tea phenols has been shown in experimental animals such as rats and mice, in transplantable tumors, carcinogen-induced tumors in digestive organs, mammary glands, hepatocarcinomas, lung cancers, skin tumors, leukemia, tumor promotion and metastasis. The mechanisms of antimutagenesis and anticarcinogenesis of tea polyphenols suggest that the inhibition of tumors may be due to both extracellular and intracellular mechanisms including the modulation of metabolism, blocking or suppression, modulation of DNA replication and repair effects, promotion, inhibition of invasion and metastasis, and induction of novel mechanisms.  相似文献   

16.
Residue levels of dimethoate and its oxon metabolite (omethoate) during tea planting, manufacturing, and brewing were investigated using a modified QuEChERS sample preparation and gas chromatography. Dissipation of dimethoate and its metabolite in tea plantation followed the first-order kinetic with a half-life of 1.08–1.27 d. Tea manufacturing has positive effects on dimethoate dissipation. Processing factors of dimethoate are in the range of 2.11–2.41 and 1.41–1.70 during green tea and black tea manufacturing, respectively. Omethoate underwent generation as well as dissipation during tea manufacturing. Sum of dimethoate and omethoate led to a large portion of 80.5–84.9% transferring into tea infusion. Results of safety evaluation indicated that omethoate could bring higher human health risk than dimethoate due to its higher hazard quotient by drinking tea. These results would provide information for the establishment of maximum residue limit and instruction for the application of dimethoate formulation on tea crop.  相似文献   

17.
The main goal of this study was to compare effects of ethanol-soluble fractions prepared from various types of teas on sucrose-induced hyperlipidemia in 5-week old male Sprague-Dawley rats. Rats (n = 6-8 per group) weighed approximately 200 g were randomly divided into control diet, sucrose-rich diet, green tea, oolong tea and black tea groups. Control-diet group was provided with modified AIN-93 diet while the others consumed sucrose-rich diet. Tea extracts (1% w/v) were supplied in the drink for green tea, oolong tea and black tea groups. Results indicated sucrose-rich diet induced hypertriglyceridemia and hypercholesterolemia. Food intake was reduced by oolong tea extract. Consuming oolong and black tea extracts also significantly decreased body weight gains and food efficiency. Hypertriglyceridemia was normalized by green and black tea drink on day 18 and by oolong tea extract on day 25, respectively. Hypercholesterolemia was normalized by green tea on day 18 and by oolong tea and black tea on day 25, respectively. Plasma HDL-cholesterol concentrations were not affected by any tea extract. The triglyeride content in the liver as well as the cholesterol content in the heart of rats fed sucrose-rich diet were elevated and were normalized by all types of tea drink tested. Although green and oolong tea extracts contained similar composition of catechin, our findings suggest green tea exerted greater antihyperlipidemic effect than oolong tea. Apparent fat absorption may be one of the mechanisms by which green tea reduced hyperlipidemia as well as fat storage in the liver and heart of rats consumed sucrose-rich diet.  相似文献   

18.
Tea is the second most commonly consumed beverage in the world. It is well recognized that the consumption of tea in high quantities can promote the development of fluorosis. The main objective of this study is to estimate the exposure to fluoride in the Azores through drinking tea prepared with water from different volcanic locations, by i) investigating the fluoride (F) content of various commercial brands of tea (Camellia sinensis) marketed in Azores and ii) comparing tea releasing rates of F according to brewing time, considering the fluoride concentration in the different types of water used for the infusion. Fluoride contents were determined by ion-selective electrode in 30 samples of drinking water from three different locations and in 450 samples of tea (black and green tea) from three different brands. Fluoride concentration in water ranged from 0.29 to 1.56 ppm (Porto Formoso and Sete Cidades village, respectively). Fluoride concentrations increased with brewing time, reaching the highest values in the Azorean black and green tea infusions. For all the studied brands, a negative correlation was found between tea fluoride contents and the pH of the water used to prepare the infusion. Fluoride concentration in infusions was significantly associated with the background fluoride concentration in drinking water. Since the fluoride concentration in groundwater varies accordingly to the geological conditions and tea consumption can contribute to fluoride intake, it is important to define the limits for tea consumption, particularly in fluoride-rich areas.
Graphical Abstract Fluoride concentrations in black and green tea for 3 minutes of brewing time and, association between fluoride concentration and pH with brewing time
  相似文献   

19.
茶叶是世界上最受人们欢迎的饮品之一,但茶叶中掺杂其他植物成分的现象时有发生。依靠传统的感官和理化检验方法难以准确判断茶叶中掺杂的植物种类。报道一种基于植物核酮糖-1,5-二磷酸羧化酶/加氧酶大亚基(rbc L)基因序列进行茶叶掺杂定性检测的方法,包括rbc L基因片段的扩增、测序和序列分析等步骤。利用所建立的方法对7份茶叶样品进行分析,发现岳阳黄茶(黄茶)和信阳毛尖(绿茶)未掺杂其他植物成分,而正山小种(红茶)、铁观音(乌龙茶)、太姥银针(白茶)、六堡茶和普洱茶(黑茶)均一定程度上混杂有其他植物成分。所建立的检测方法对样品的需求量小,操作简便,检测结果可靠性高,能定性检测各类茶叶中是否掺杂及掺杂了何种植物成分。  相似文献   

20.
崂山茶区茶树根围AM真菌多样性   总被引:5,自引:1,他引:4  
为调查崂山茶区土壤中丛枝菌根(AM)真菌资源的分布状况, 于2007年9月从青岛崂山茶区12个茶园采集茶树(Camellia sinensis)根围土样, 采用湿筛倾注–蔗糖离心法分离AM真菌, 测定其物种丰度、频度、孢子密度、相对多度、重要值、多样性指数等。共分离到AM真菌3属22种, 无梗囊霉属(Acaulospora)出现的频度最高, 其次是球囊霉属(Glomus)。AM真菌孢子密度以晓望村茶园最高, 高家村茶园最低; 种丰度以常家村茶园最高; 常家村茶园和万来客茶园的Shannon-Wiener指数显著高于其他茶园。光壁无梗囊霉(Acaulospora laevis)是北崂茶厂、万里江茶园、樱山春茶园、万里江有机茶园、常家村茶园和桑园村茶园的优势种; 波状无梗囊霉(Acaulospora undulata)为万里江有机茶园和万来客茶园的优势种; 隐球囊霉(Glomus occultum)为樱山春茶园、晓望村茶园和万来客茶园的优势种。应用典型相关分析(CCA)对环境因子与崂山茶区AM真菌群落组成的关系进行了分析, 各因子的影响大小依次为: 土壤速效磷含量>土壤有机质含量>种植年限>土壤碱解氮含量>土壤pH值>土壤速效钾含量。  相似文献   

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