共查询到20条相似文献，搜索用时 15 毫秒
1.
朱砂根种子萌发过程中酶活性的动态变化 总被引：2，自引：0，他引：2
测定了50mg／L GA3和200mg／L 6-BA浸种后的朱砂根种子在萌发过程中酶活性的动态变化。结果表明：在萌发过程中,α-淀粉酶活性整体呈上升趋势,50mg／LGA3处理的活性最大;200mg／L 6-BA处理后的过氧化氢酶（CAT）和过氧化物酶（POD）活性最大,CAT活性是先上升后下降,露白到发芽阶段下降;POD活性一直呈上升趋势,在吸胀到露白阶段,其活性上升较平稳,而在种子露白后到发芽阶段开始迅速上升。 相似文献
2.
MuJun UeharaTohru LiJianzhang FurunoTakeshi 《中国林学(英文版)》2004,6(2):1-5
The antioxidant activity of solvent extracts from two main bamboo species, moso bamboo (Phyllostachys pubescens) and madake bamboo (P bambusoides) in Japan, was first evaluated by scavenging free radical of 1,1-diphenyl-2-picrylhydrazyl (DPPH), the inhibition activity for peroxidation of linoleic acid, and the reduction power. The methanol-extracts of moso bamboo culms and madake bamboo leaves presented stronger antioxidant activity compared with DPPH scavenging activity. Methanol-extract of moso bamboo culms was further fractionated by different solvents and n-butanol soluble fraction exhibited the most significant activity in the DPPH scavenging assay. The fractionation of n-butanol soluble extract was isolated by silica gel column with gradient mixture solvent of chloroform and methanol. The isolated fractions were directed by the antioxidant activity measured by scavenging the stable DPPH free radical. It was observed that most of the eluted fractions showed the antioxidative activity. Fractions acquired from elution with the mixture solvent of chloroform and methanol (10:1-5:1) showed stronger antioxidant activity than the other fractions. 相似文献
3.
以转Bt基因南林895杨树叶片饲喂杨扇舟蛾,研究 Bt 毒蛋白对害虫体内代谢酶的影响。结果表明: 酯酶和羧酸酯酶明显受到抑制。中肠酯酶活性在取食 4 ～ 48 h 内持续下降,羧酸酯酶活性在前期 4 h 有所上升但随后持续下降。多功能氧化酶活性从 24 h 起,受抑而下降,但不显著。谷胱甘肽 S - 转移酶活性在前 36 h 内波动不大,48 h 后显著受抑。乙酰胆碱酶的活性无明显受抑。超氧化物歧化酶活性 12 h 后略升高,然而在取食 12 ～ 48 h活性持续下降,与之相反,过氧化物酶活性在 4 ～ 48 h呈上升状态。过氧化氢酶活性在 4 ～ 12 h 呈下降状态,24 ～48 h呈上升状态。转 Bt 基因杨树主要通过抑制酯酶和羧酸酯酶并扰乱超氧化物歧化酶、过氧化氢酶、过氧化物酶的协调作用干扰害虫的正常生理代谢,起到杀虫作用。 相似文献
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水浴处理板栗MA贮藏期间抗氧化酶活性变化规律 总被引：1，自引：0，他引：1
以北京昌平的燕昌板栗为试验材料,研究经不同水浴处理后,板栗MA(Modify atmosphere)贮藏期间抗氧化酶活性的变化规律。结果表明:NaClO水浴处理对板栗内PPO、外PPO活性有抑制作用,除1 000 mg.L-1NaClO处理使板栗外PPO活性一直高于对照外,其余各处理的PPO活性在整个贮藏期间一直低于对照;POD活性的变化规律与PPO活性的变化规律类似,但在贮藏180 d时,NaClO处理的内POD活性高于对照,其中1 000 mg.L-1NaClO处理的内POD活性与对照存在显著差异;100 mg.L-1NaClO和500 mg.L-1NaClO处理使板栗SOD活性升高,而1 000 mg.L-1NaClO处理则使SOD活性降低;NaClO处理板栗提高了板栗的CAT活性,但CAT活性变化趋势与对照相同。 相似文献
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The ethanolic extracts of the leaves and flowers of Cleome viscosa and roots of Gmelina asiatica were tested for antimicrobial activity. The two plants exhibited a broad spectrum of antimicrobial activity, particularly significative against Escherichia coli , Proteus vulgaris and Pseudomonas aeruginosa. The leaf extract of C. viscosa showed moderate activity against pathogenic fungi. 相似文献
7.
为探究苏云金杆菌(Bacillus thuringiensis Bt)对蚜虫的生物活性影响及作用方式,以苏云金亚种(Bacillus thuringiensis subsp.thuringiensis)为目的菌株,以发酵产物为材料。利用5种不同浓度的菌液分别喷雾处理柳蚜,72h校正死亡率为29.74%～78.88%,其浓度与及死亡率呈正相关关系。苏云金杆菌亚种发酵液和发酵液滤液处理柳蚜后,12～24h柳蚜超氧化物歧化酶(SOD)比活力均被抑制,其抑制率分别为21.06%～38.11%和4.69%～36.79%,其中18h、24h对SOD比活力的抑制达显著水平(p<0.05)。发酵液和滤液处理组18h前对柳蚜过氧化氢酶(CAT)比活力的影响总体呈激活趋势,其中发酵液和滤液处理组分别在18h、12h对柳蚜CAT的激活率最高,其CAT比活力分别为对照的1.8890倍和2.9463倍。滤液处理组对柳蚜POD比活力总体呈激活作用,其激活率为14.78%～57.39%;发酵液处理组6h和18hPOD比活力显著高于对照,其他时间点POD比活力与对照无显著差异。 相似文献
8.
Zeen Huang Koh Hashida Rei Makino Fumio Kawamura Kuniyoshi Shimizu Ryuichiro Kondo Seiji Ohara 《Journal of Wood Science》2009,55(3):225-229
Heartwoods of 22 African tropical wood species were extracted with methanol and the contents of total phenolic compounds in
these extracts were measured. Three bioassays were conducted to evaluate the antioxidant activity, tyrosinase inhibitory activity,
and antifungal activity of the methanol extracts. The results indicated that the extracts from 13 species exhibited high antioxidant
potential, and their inhibitory concentrations that caused 50% scavenging of the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical
(IC50) were less than 10 μg/ml. The crude extract from Cylicodiscus gabunensis showed the highest antioxidant activity, and was even higher than that of (+)-catechin, which is known as a potent antioxidant.
There was a good correlation between the antioxidant activity and the content of total phenolic compounds, indicating that
phenolic compounds played a predominant role in the antioxidant property of the wood extracts. Among all 22 species, only
1 species, Milicia excelsa, contained extractives that showed very high tyrosinase inhibitory activity. The extracts from 9 species showed high antifungal
activity. No consistent relationship was observed between the tyrosinase inhibitory activity or antifungal activity and the
content of total phenolics in the extracts.
Part of this article was presented at the 56th Annual Meeting of the Japan Wood Research Society, Akita, August 2006 相似文献
9.
The Breynia cernua leaves, stem and root barks and heart-woods extracted with petrol, dichloromethane, ethyl acetate, butanol and methanol gave fractions with varied level of antimicrobial activity. The best activity was exhibited by the methanol extract of the root bark followed by its butanol fraction. These were the only fractions exhibiting a good level of antifungal activity as compared to the standard. The dichloromethane fraction of the stem bark also demonstrated good activity. 相似文献
10.
对华北地区主要经济树种仁用杏树各器官在不同生育期问四种不同处理下的多酚氧化酶(PPO)活性进行了测定，结果表明：(1)仁用杏树体各器官内的多酚氧化酶活性在整个年循环周期内呈规律性变化。叶中PPO活性整体水平在10月份最高；枝、干、主根、侧根中的PPO活性均以5月和3月极显著地高于7月和10月。(2)PPO活性与仁用杏树体的抗寒性、地上部分的生长发育有关，并可作为仁用杏树抗寒性的生化指标。(3)Cu、Zn两种营养元素通过影响PPO活性来影响仁用杏树生长。 相似文献
11.
The ethanolic extracts of the leaves and flowering tops of Acanthospermum hispidum showed varying degrees of activity against a wide range of pathogenic bacteria. The activity resided mostly in the polar fractions of the alcoholic extract, being only slight in the non-polar fractions. No activity was observed for the aqueous extract of the fresh plant material. 相似文献
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由于人工林面积的不断扩大和人类经营措施的不合理,致使世界范围内人工林地力衰退现象十分严重.我国主要造林树种杉木(Cunninghamia lanceolata(Lamb.) Hook)、落叶松(Larix spp.)、桉树(Eucalyptus spp.)等存在地力衰退现象[1-4],其中田大伦[5]、杨玉盛[6]、叶绍明[7]等分别对杉木、桉树连栽进行了较深入研究,得出连栽林地土壤理化性质、林下植物、枯落物生物量及养分循环等有下降趋势. 相似文献
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以红掌‘Dakota’为试材,研究硼及基质对植株SOD、POD比活性及MDA含量的影响。结果表明:3种不同基质间氮、磷、钾的各量和总量差异都很大,以进口泥炭最低、中药渣最高、国产泥炭介于中间;相反,有机质含量以进口泥炭最高、中药渣最低。同种基质处理中,不同硼浓度对叶片SOD、POD比活性及MDA含量的影响差异显著,SOD和POD比活性变化规律相似,而MDA含量与SOD和POD比活性变化规律相反;硼可以提高叶片SOD、POD比活性,试验中以B3处理值较高。相同硼浓度处理中,不同基质对叶片SOD、POD比活性及MDA含量的影响差异不显著;但碱性基质降低植株SOD、POD比活性,生产中不宜采用。试验范围内,以基质处理A5(进口泥炭:中药渣:珍珠岩=2∶1∶1)与硼处理B3(40μmol/l)组合为规模化生产首选配方。 相似文献
15.
八角林地土壤酶活性和养分的分布特点及其相关分析 总被引：8，自引：4，他引：8
研究了广西高峰林场和大明山自然保护区八角林地土壤酶活性(包括过氧化氢酶、转化酶、脲酶、蛋白酶和酸性磷酸酶)和养分的分布特点及土壤酶活性与土壤养分的关系。结果表明:(1)土壤养分含量和酶活性以表层土壤的最大,随土壤深度的增加逐渐下降;(2)坡位不同,土壤养分含量和主要酶活性也不同,呈现下坡>上坡的趋势;(3)土壤酶活性与土壤有机质、全氮、全磷、水解氮、速效磷和速效钾密切相关,不同的土壤酶活性之间存在极显著的相关性。因此,土壤酶活性可作为八角林地土壤肥力的指标之一。 相似文献
16.
为揭示河竹鞭根对淹水环境的生理响应机制,以在淹水环境中能长期生存的河竹为材料,测定了人工喷灌供水(对照)、淹水6个月的河竹1年生竹鞭上的一级根、二级根的根系活力、抗氧化酶活性和膜脂过氧化、渗透调节物质含量。研究结果表明:河竹根系活力、抗氧化酶活性、MDA含量、相对电导率和可溶性蛋白含量总体上一级根明显高于二级根。长期淹水环境下,河竹一级根、二级根的根系活力、抗氧化酶活性较对照均有显著降低,相对电导率、MDA含量显著升高,水中生长根的根系活力、CAT活性显著高于土中生长根,SOD、POD活性则相反,并能通过维持总体上较高水平的根系活力、抗氧化酶活性、可溶性蛋白含量来适应长期淹水环境的胁迫,尤其是一级根和水中生长根。河竹鞭根通过抗氧化系统的平衡调节作用来适应长期淹水环境,维持生存,其中一级根对淹水环境的响应明显强于二级根,水中生长根在适应淹水环境上起到重要作用。 相似文献
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分别以甲醇、丙酮、水为提取剂,提取山胡椒叶片的次生代谢产物,并测定3种不同提取液的次生代谢产物含量及体外抑菌效果,评价山胡椒的药用价值,为山胡椒的进一步开发利用提供理论依据。实验结果表明,不同提取液中次生代谢产物含量均是黄酮>鞣质>游离蒽醌>皂甙>生物碱;3种提取液的次生代谢产物含量及抑菌活性存在较大差异,不同提取液对枯草芽孢杆菌的抑菌活性要高于大肠杆菌、水可作为山胡椒叶片次生代谢产物的良好提取剂。通径分析表明,影响不同提取液对枯草芽孢杆菌的抑菌活性的次生代谢产物主要是总黄酮和总皂甙,影响提取液对大肠杆菌抑菌活性的次生代谢产物主要是总皂甙。 相似文献
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Antimicrobial activity of Cassia alata. 总被引：2，自引：0，他引：2
The methanol extracts of leaves, flowers, stem and root barks of Cassia alata showed a broad spectrum of antibacterial activity. The activity was increased on fractionation (petrol, dichloromethane, ethyl acetate), the dichloromethane fraction of the flower extract being the most effective. No activity was shown against tested moulds. 相似文献
19.
The antibacterial activity of the methylene chloride and methanol extracts of Chrysantemum coronarium fresh flower heads was investigated. The methylene chloride extract showed discrete antimicrobial activity. 相似文献
20.
对阜新低山缓丘区大扁杏、南国梨林农复合系统构建初期土壤酶活性演化动态进行研究。结果表明,每种林农复合系统土壤酶活性都显示土壤表层高于下层。在植物生长期,过氧化氢酶、脲酶和蔗糖酶活性呈现不同的变化特征：过氧化氢酶都呈“山脊”状变化且7月活性最高。在南国梨林农复合系统中,脲酶活性呈直线增长,在9月活性达到最高值;在大扁杏林农复合系统中,脲酶活性呈先升后降的变化特征。在各种林农复合系统中,蔗糖酶活性在6月较低,7-8月升高,9月开始逐渐降低。3种土壤酶活性间具有相关性,其中脲酶和蔗糖酶活性关系最为密切,相关系数在0．713以上。 相似文献