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1.
选取广西、湖南等地野生葡萄,与经典酿酒葡萄比较,研究抗氧化活性和活性物质,同时监测葡萄酒发酵过程中各指标的动态变化,并对不同品种葡萄酒的抗菌性进行研究。结果表明:赤霞珠的酚类含量和抗氧化活性高于野生葡萄和玫瑰香葡萄,但野生葡萄酒的抗菌性能显著优于赤霞珠和玫瑰香葡萄酒。葡萄酒在发酵过程中其抗氧化活性和酚类物质含量均随发酵过程的进行而升高;总抗氧化活性与总酚含量、氧自由基清除能力与原花青素含量成显著正相关,相关系数均大于0.989;总花色苷含量在发酵初期上升,后期下降,葡萄酒颜色变浅。  相似文献   

2.
葡萄籽中原花青素提取方法优化处理   总被引:7,自引:0,他引:7  
吕国红  傅星 《生态学杂志》2004,23(5):241-244
溶剂提取法是提取葡萄籽原花青素的常用方法 ,然而 ,在不同提取条件下 ,提取效果并不一致。利用水、甲醇、乙醇、丙酮及它们的水溶液提取葡萄籽中的原花青素 ,而后用铁盐催化比色法测原花青素含量 ,考察了提取剂的浓度、粉碎度对提取的影响。在优化处理的基础上 ,获得了有效的提取条件 :葡萄籽粉碎度 10 0目 ,提取剂 70 %甲醇水溶液。  相似文献   

3.
Atherosclerosis is a disease of the arteries in which fatty plaques develop on the inner arterial wall, which eventually obstructs blood flow. Identified risk factors for atherosclerosis include genetics, diet, lifestyle, smoking, circulating lipid and cholesterol levels, and molecular and circulating signals of chronic vascular inflammation. The link between flavonoids and atherosclerosis is based partly on the evidence that some flavonoids possess antioxidant properties and have been shown to be potent inhibitors of LDL oxidation in vitro. Hypercholesterolemia, a significant cardiovascular risk factor is prevalent in the American population. Grape seed proanthocyanidin extracts are known to exhibit a broad spectrum of chemopreventive and cardioprotective properties against oxidative stress. A recent study has shown that a combination of IH636 grape seed proanthocyanidin extract (GSPE) and a niacin-bound chromium (NBC) can decrease total cholesterol, LDL and oxidized LDL levels in hypercholesterolemic human subjects. In this study, we assessed the efficacy of GSPE supplementation in hamsters, singly and in combination with NBC, since these animals have a similar lipid profile to hypercholesterolemic humans when fed a hypercholesterolemic diet of 0.2% cholesterol and 10% coconut oil (HCD). After 10 weeks of feeding HCD, these animals developed foam cells, which is a biomarker of early stages of atherosclerosis. Atherosclerosis (% of aorta covered with foam cells) was reduced by approximately 50% and 63% following supplementation of these animals with 50 mg/kg and 100 mg/kg of GSPE, respectively, in conjunction with a HCD, while approximately 32% reduction was observed following supplementation of GSPE plus NBC. A minimum of 7–9 animals were used in each study group. GSPE alone and in combination with NBC exerted a pronounced effect on the cholesterol, and triglyceride levels, as well as oxidative lipid damage as demonstrated by the formation of thiobarbituric acid reactive substances (TBARS). This data demonstrates that GSPE and NBC may provide significant health benefits by dramatically ameliorating the incidence of atherosclerosis as demonstrated by reducing the formation of foam cells.  相似文献   

4.
鼠类对山杏(Prunus armeniaca)种子扩散及存活作用研究   总被引:15,自引:1,他引:15  
张知彬  王福生 《生态学报》2001,21(5):839-845
虽然有关鼠类搬运森林种子的证据已很清楚,但这些初移走种子的存活情况却知之甚少。提出了一个新的标记和跟踪种子的方法--标签法,即将种子拴一带有编码的细长金属片,研究了北京东灵山地区山杏(Prunus armeniaca)种子的扩散距离和存活率。于1998年6月19-20日,7月3日和10月23日共在24个样点释放1440粒山杏种子。几科所有释放的种子在10d内被鼠类取走,夏天释放的种子比秋天释放的种子消失的速度快。大多数种子的扩散距离在20m以内,小于鼠类的活动距离,鼠类吃掉种子的速度很快,但当种子变得稀少时,种子存活率有所提高。山杏种子6、7月份的每日存活率小于其它月份的每日存活率。  相似文献   

5.
Aims:  To search for antimicrobial compounds against pathogenic bacteria from grape vines ( Vitis spp.). To investigate the antimicrobial efficacy of active compounds towards methicillin-resistant Staphylococcus aureus (MRSA).
Methods and Results:  The root extracts of taiwanese wild grape ( Vitis thunbergii var. taiwaniana ) showed marked activities against Gram-positive bacteria using the disc diffusion method. After purification, the active compound 1 was confirmed as heyneanol A by mass spectroscopy and nuclear magnetic resonance. Heyneanol A showed an minimum inhibitory concentration (MIC) value of 2  μ g ml−1 towards MRSA and a value of 2 to 4  μ g ml−1 for Enterococcus faecium , S. aureus , Streptococcus agalactiae and Streptococcus pyogenes . In addition, the contents of heyneanol A were determined as 36 mg g−1 in roots of taiwanese wild grape.
Conclusions:  The root extracts of grapevines have good antimicrobial activities towards some strains of Gram-positive pathogens. Heyneanol A, the major antimicrobial compound, is especially active towards MRSA. In addition, the abundances of heyneanol A and other stilbenes in the roots of grapevines make it possible to produce natural antimicrobial compounds from this plant species.
Significance and Impact of the Study:  This study reports for the first time the antimicrobial compounds in the root extracts of grapevines. The results will have clinical significance owing to their activities against MRSA.  相似文献   

6.
野生人参种子的超低温保存   总被引:2,自引:0,他引:2  
人参(PanaxginsengC.A.Mey.)是珍贵的药用植物,由于长期过度采挖,资源枯竭,现存于我国东北地区的野生人参已处于濒临绝灭的边缘,被列为国家一级重点保护植物[1,2]。所以在加强其就地保护的同时,人参种质资源的迁地保存也是非常必要的。按...  相似文献   

7.
野生祁白术的营养成分分析   总被引:3,自引:0,他引:3  
对安徽野生祁白术根中的水分、灰分、粗蛋白、粗脂肪、粗纤维、总糖、Vc、矿质元素及氨基酸的组成和含量进行了分析。结果显示野生祁白术至少含有17种氨基酸,总糖含量为54.77%、Arg含量为16.1mg.g^-1干重,钙含量为9.90mg.g^-1干重。祁白术除可作为药用外,还能应用于功能性食品开发。  相似文献   

8.
Cell walls have been isolated from the mesocarp of mature grape (Vitis vinifera L.) berries. Tissue homogenates were suspended in 80% (v/v) ethanol to minimise the loss of water-soluble wall components and wet-sieved on nylon mesh to remove cytoplasmic material. The cell wall fragments retained on the sieve were subsequently treated with buffered phenol at pH 7.0, to inactivate any wall-bound enzymes and to dislodge small amounts of cytoplasmic proteins that adhered to the walls. Finally, the wall preparation was washed with chloroform/methanol (1:1, v/v) to remove lipids and dried by solvent exchange. Scanning electron microscopy showed that the wall preparation was essentially free of vascular tissue and adventitious protein of cytoplasmic origin. Compositional analysis showed that the walls consisted of approximately 90% by weight of polysaccharide and less than 10% protein. The protein component of the walls was shown to be rich in arginine and hydroxyproline residues. Cellulose and polygalacturonans were the major constituents, and each accounted for 30–40% by weight of the polysaccharide component of the walls. Substantial varietal differences were observed in the relative abundance of these two polysaccharides. Xyloglucans constituted approximately 10% of the polysaccharide fraction and the remainder was made up of smaller amounts of mannans, heteroxylans, arabinans and galactans. Received: 26 November 1996 / Accepted: 30 January 1997  相似文献   

9.
SYNOPSIS. Plasmodium (Huffia) hermani sp. n. is described from wild turkeys (Meleagris gallopavo Linnaeus) in Florida. It produces rounded schizonts with 6–14 nuclei arranged peripherally as a rosette and elongate, slender gametocytes with irregular margins. Asexual stages parasitize all cells in the erythrocyte series and, in heavy infections, predominantly occur in erythroblasts and their precursors. Presence and degree of pigmentation vary with maturity of the host cell. Gametocytes occupy erythrocytes only, with pigment dispersed in black granules throughout the cytoplasm. Cells containing schizonts are often rounded and enlarged and those parasitized by gametocytes may be somewhat distorted in shape by lateral hypertrophy. Host cell nuclei may be displaced, but are not distorted, except slightly by pressure from the parasite. Plasmodium hermani differs from P. (Giovannolaia) durae by producing low level (> 6%), nonlethal parasitemias in turkey poults, an absence of phanerozoites in capillary endothelium of the brain and viscera, and inability to infect chicks. Plasmodium hermani is more like P. (Huffia) elongatum in gametocyte morphology, schizogony in all types of erythrocyte precursors, with gametocytes occurring in erythrocytes only, and concentration of schizonts in heavy infections in bone marrow and spleen. It differs from P. elongatum by its lack of infectivity to passeriform and anseriform hosts and by a strong immune response which develops in infected birds.  相似文献   

10.
【目的】从东乡野生稻(Oryza rufipogon)中分离和鉴定内生放线菌,对其进行抗菌活性筛选,并分析高抗菌活性菌株S123的次级代谢产物。【方法】采用S培养基对东乡野生稻内生放线菌进行分离、纯化,并构建16S rRNA基因序列系统发育进化树进行菌株鉴定。以琼脂扩散法和菌丝生长速率法进行抗菌活性筛选,同时设计简并引物检测菌株I型聚酮合酶(PKS-I)基因。对具广谱抗菌活性的菌株S123进行分批大量发酵,运用多种色谱方法对发酵产物进行分离、纯化,利用MS和NMR分析鉴定化合物的结构。【结果】从东乡野生稻中共分离到11株内生放线菌,分别属于链霉菌属(8株)和假诺卡氏属(3株)。其中有8株具有抗菌活性,8株呈现I型PKS阳性。从高抑菌活性菌株S123中分离到化合物Nigericin和17-O-demethylgeldanamycin,其中Nigericin对金黄色葡萄球菌、枯草芽孢杆菌及水稻纹枯病菌均有抑制活性。【结论】对东乡野生稻内生放线菌进行了分离、鉴定和抗菌活性筛选,并从中分到两种与I型PKS基因相关活性的化合物Nigericin和17-O-demethylgeldanamycin,为研究东乡野生稻内生放线菌的多样性和次级代谢产物的分离提供依据。  相似文献   

11.
为了探讨不同抗性水平砧木及品种对根瘤蚜吸引及驱避效应以及鉴定挥发性物质组分,采用离体根段培养法测定葡萄根瘤蚜Phylloxera viticola Fitch对砧木5BB,140Ru及栽培品种巨峰的选择性,发现根瘤蚜对栽培品种巨峰的根段具有很强的选择性,至接种后3 d,67.13%的根瘤蚜优先选择巨峰;而对5BB和140Ru的选择性却很差,分别有15.29%和17.58%的根瘤蚜选择5BB及140Ru。根瘤蚜在不同品种根段上的生长发育和繁殖也存在明显差异。对砧木5BB和巨峰根系的挥发性组分进行测定,发现2个品种挥发物独有组分数量均较高,巨峰独有组分为23个,占总成分数的48.94%,5BB的独有组分为32个,占总成分数的57.14%。5BB和巨峰的共有组分为24个,主要成分均为亚油酸甲酯和反油酸甲酯,但含量有所不同,其中,5BB以倍半萜类的丁香醇及脂肪酸甲酯类的亚油酸甲酯,反油酸甲酯,棕榈油酸甲酯含量较高,高于巨峰中相应物质含量的4.23%~6.46%,而巨峰以邻苯二甲酸二丁酯及胆甾烷含量较高,分别高于5BB相应组分含量的6.81%和1.07%。结果说明葡萄根瘤蚜对不同抗性水平砧木及品种确实存在不同的选择性,并且不同抗性水平的砧木及品种的挥发性物质存在显著差异。  相似文献   

12.
野生扬子鳄种群及栖息地现状研究   总被引:24,自引:2,他引:24  
1999年7~8月及2000年8~9月,利用GPS、激光测距仪等,采用夜间灯光照射计数方法,对 有野生扬子鳄(Alligator sinensis)存在的安徽省宣州、泾县、广德、郎溪、南陵等5 县市的26个地点进行了调查,包括扬子鳄国家级自然保护区的13个指定保护点。结果发现: 目前野生扬子鳄主要生存在第一类栖息地(1999年50.7%、2000年40.0%),面积为17.38 hm2;其他两类栖息地的野生扬子鳄分布比率较小(各为1999年24.0%、2000年30.9%、1999 年25.3% 、2000年29.1%),面积分别为22.04hm2、19.03hm2。两年的平均生态密度分别为1.28条/hm2和1.79条/hm2,野生扬子鳄种群数量为145条。其种群已明显分为至少18个数 量不等且相互隔离的地方种群。建议恢复足够大的栖息地,并放饲养鳄于其中以重新 建立有效野生种群。  相似文献   

13.
Grape proanthocyanidins (GPCs) are a family of naturally derived polyphenols that have aroused interest in the poultry industry due to their versatile role in animal health. This study was conducted to investigate the potential benefits and appropriate dosages of GPCs on growth performance, jejunum morphology, plasma antioxidant capacity and the biochemical indices of broiler chicks. A total of 280 newly hatched male Cobb 500 broiler chicks were randomly allocated into four treatments of seven replicates each, and were fed a wheat–soybean meal-type diet with or without (control group), 7.5, 15 or 30 mg/kg of GPCs. Results show that dietary GPCs decrease the feed conversion ratio and average daily gain from day 21 to day 42, increase breast muscle yield by day 42 and improve jejunum morphology between day 21 and day 42. Chicks fed 7.5 and 15 mg/kg of GPCs show increased breast muscle yield and exhibit improved jejunum morphologies than birds in the control group. Dietary GPCs fed at a level of 15 mg/kg markedly increased total superoxide dismutase (T-SOD) activity between day 21 and day 42, whereas a supplement of GPCs at 7.5 mg/kg significantly increased T-SOD activity and decreased lipid peroxidation malondialdehyde content by day 42. A supplement of 30 mg/kg of GPCs has no effect on antioxidant status but adversely affects the blood biochemical indices, as evidenced by increased creatinine content, increased alkaline phosphatase by day 21 and increased alanine aminotransferase by day 42 in plasma. GPC levels caused quadratic effect on growth, jejunum morphology and plasma antioxidant capacity. The predicted optimal GPC levels for best plasma antioxidant capacity at 42 days was 13 to 15 mg/kg, for best feed efficiency during grower phase was 16 mg/kg, for best jejunum morphology at 42 days was 17 mg/kg. In conclusion, GPCs (fed at a level of 13 to 17 mg/kg) have the potential to be a promising feed additive for broiler chicks.  相似文献   

14.
Numerical taxonomy of the wild bananas (Musa)   总被引:2,自引:0,他引:2  
  相似文献   

15.
葡萄贮期脱落酸(ABA)变化的研究   总被引:5,自引:0,他引:5  
试验研究了葡萄贮期脱落酸 ( ABA)的变化 ,结果表明 :葡萄贮期 ABA含量呈抛物线形变化 ,有明显的高峰出现 ,低温 ( 0± 0 .5℃ )贮藏具有推迟 ABA峰期和降低峰值的作用 ,经用 9种植物生长调节剂和 2种化学药品对葡萄果穗处理试验 ,三碘苯甲酸 ( TIBA)对 ABA的形成有极强的抑制作用 ,吲哚 - 3-乙酸 ( IAA)、赤霉素 ( GA3)、萘乙酸 ( NAA)和 6-苄基氨基嘌呤 ( 6- BA)对 ABA的形成也具有拮抗作用 ,矮壮素 ( CCC)、比久 ( B9)、乙烯利 ( CEPA)和外源脱落酸对 ABA的形成有促进作用。  相似文献   

16.
伏牛山北坡野猪(Sus scrofa)泥浴场的生境特征   总被引:6,自引:0,他引:6  
邓天鹏  郑合勋  曾国仕 《生态学报》2009,29(2):1001-1008
2005年6月至8月,在伏牛山北坡对野猪的泥浴场特征进行了研究.野外设置了42个20×20m2样方和14个生态因子,以此为基准运用聚类分析和主成分分析的方法,对野猪泥浴场进行了分析,结果表明,野猪泥浴场的生境特征为:(1)安全舒适因子:无倒木、无树桩、隐蔽距离30m以下、黄泥土质、郁闭度80%以上;(2)植被地形因子:乔木距离适中、灌木距离小于1m、坡度小于30°;(3)植被类型因子:高度倾向阔叶林;(4)干扰因子:人为干扰距离大于500 m;(5)海拔因子:海拔高度大于1000 m.在水源距离和坡位两项上没有明显的偏向.  相似文献   

17.
海南主要普通野生稻的调查及利用RAPD技术进行鉴别分析   总被引:2,自引:0,他引:2  
通过对海南现存的主要普通野生稻资源进行考察,报道了海南主要普通野生稻的最新生存状况;并用RAPD技术对其进行分析。从供试材料中筛选出具有多态性的RAPD引物13条,共扩增出155条带,其中多态性条带120条,多态性条带比率(PPB)值为77.42%。UPGMA聚类结果表明:海南主要普通野生稻之间遗传关系较复杂、差异较明显,并将海南主要普通野生稻资源划分为5个小类群,可以很好地将海南本地野生稻与收集保存的野生稻鉴别开来,为海南普通野生稻资源的合理利用与有效保护提供了重要依据。  相似文献   

18.
Proteins that have homology with dehydrins have been identified immunologically in the desiccationsensitive (recalcitrant) seeds of English oak (Quercus robur L.), European chestnut (Castanea sativa L.), horse chestnut (Aesculus hippocastanum L.), sycamore (Acer psuedoplatanus L.) and silver maple (Acer saccharinum L.), and in the desiccation-tolerant seeds of Norway maple (Acer platanoides L.). The mRNA for a late embryogenesis abundant (LEA) protein (dehydrin) was also detected by Northern blotting, using a cDNA clone (D11) from cotton embryos, in the recalcitrant and orthodox seeds. Medium-stringency washing was required to detect this hybridization. InQ. robur the amount of dehydrin protein increased during seed development, andLEA mRNA was induced by limited desiccation and by abscisic acid. Confirmation of the presence of dehydrin mRNA in matureQ. robur andC. sativa seeds was obtained by in-vitro translation of the extracted polyadenylated RNA followed by analysis of the immunoprecipitation products. Thus the presence of dehydrin proteins is not sufficient to confer desiccation tolerance on truly recalcitrant seeds, nor can their presence or absence be used as clear criteria for identification of recalcitrant seeds.  相似文献   

19.
鲁长虎 《生态学杂志》2005,24(5):567-572
种子植物在果实(种子)成熟后需要防御食果实动物捕食种子,同时要传播种子至适宜萌发的生境。很多植物依赖食果实动物传播种子,称动物传播植物。果实(种子)化学防御是抵御种子捕食者的重要手段。果实(种子)中次生物质包括各种生物碱、生氰糖苷、萜类和酚类等,种类繁多;次生物质的含量随果实成熟过程而变化。次生物质可以抵御动物的捕食,其毒性对种子传播者和种子捕食者没有选择性,即具泛毒性。果肉中的次生物质也可以起到轻泻剂的作用,缩短种子在动物消化道的滞留时间,以影响传播效率。果实(种子)次生物质的产生不受植物环境条件的影响,其产生与果实质量有关。在温带地区,通常SS型果实次生物质含量低,而FL型果实含量高。食果实动物可通过调整捕食行为、摄取环境中特殊物质和获得丰富营养等3个方面适应次生物质。果实(种子)中次生物质的研究对动植物相互作用、协同进化理论具有重要的意义。  相似文献   

20.
The effect of sodium dodecyl sulphate, urea, guanidinium hydrochloride and heat on the oligomeric structure of the 11 S protein of sunflower has been determined. Sodium dodecyl sulphate directly dissociates the protein to 2 S subunits, whereas urea and guanidinium hydrochloride dissociate it through an intermediate 7 S protein. Heating the protein at 90‡C for 20 min caused dissociation of the 11 S protein, without any precipitation.  相似文献   

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