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为寻找新型微生物农药,对分离自牛蒡茎的一株共生真菌NJ-1菌丝体和发酵液粗提物分别进行杀虫活性研究。采用组织块法从健康牛蒡植物的茎中进行菌株分离;采用卤虫作为生物模型进行杀虫活性物质的筛选。通过PCR扩增鉴定真菌NJ-1为四孢脉孢菌(Neurospora tetrasperma);该真菌菌丝体和发酵液粗提物对卤虫的半数致死量(LD50)分别是0.84 mg/mL和0.27 mg/mL;经与三种常见化学农药氯氰菊酯、敌敌畏和氧乐果对卤虫半数致死量对比,该真菌发酵液粗提物LD50是对照组活性最好的敌敌畏LD50的2.3倍。牛蒡共生真菌NJ-1粗提代谢物具有很强的杀虫活性,可为新型微生物农药开发提供生物来源。 相似文献
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从大叶醉鱼草的叶子中分离得到一株内生真菌LL3026,以卤虫模型测稀释后发酵液的杀虫活性,结果表明LL3026发酵液杀虫活性较强,且温度、光照及紫外照射对LL3026发酵液杀虫活性影响不显著;采用分子生物学方法对LL3026菌株rDNA的ITS基因(ITS-5.8S rDNA)进行PCR扩增、测序,构建系统发育树。ITS基因显示其属于刺盘孢属真菌。 相似文献
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为进一步开发牛蒡在生物抗虫农药方面的应用价值,对牛蒡提取物进行了抗卤虫活性测试,并对抗虫活性较强的组分进行GC-MS分析.将健康新鲜的牛蒡的乙醇粗提取物经水分散,分别用石油醚、乙酸乙酯和正丁醇萃取,对石油醚、乙酸乙酯、正丁醇和水四相提取物分别进行活性检测,结果表明它们对卤虫的半致死浓度IC50分别为0.13、0.17、1.25、0.19 mg·mL-1,其中石油醚相杀虫效果最好.对石油醚相的化学成分进行分析,共检测出51种成分,鉴定了其中39个化合物并测定了其相对含量,其中主要成分为棕榈酸乙酯(27.791%)、萜类化合物(21.311%)、饱和烃类(19.637%),这三类物质相对含量之和占总提取物的68.739%. 相似文献
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有毒亚历山大藻对卤虫存活率和摄食率的影响 总被引:1,自引:0,他引:1
研究了有毒亚历山大藻对卤虫存活率和摄食率两方面的影响,得出以下结论:在卤虫存活率实验中,有毒亚历山大藻在2000cells/ml的密度下,对卤虫具有致死效应,卤虫在24-168h内全部死亡;在摄食实验中,有毒亚历山大藻对卤虫的摄食产生明显的抑制作用,卤虫对有毒藻的平均摄食率明显低于无毒藻组和混合实验组。在加入无毒藻东海原甲藻的混合培养状态下。卤虫存活率上升,30-60min摄食率增加,东海原甲藻在一定程度上可以减轻塔玛亚历山大藻对卤虫的毒害作用。有毒藻产生的PSP毒素并非导致卤虫死亡的主要原因,毒害作用可能与出现在卤虫体外的黏附物质有关。通过对3个不同生长期卤虫的研究发现,后无节幼体卤虫对有毒亚历山大藻的毒害作用最为敏感。 相似文献
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研究了东海原甲藻的基本营养组成,并就赤潮密度下的东海原甲藻(Prorocentrum donghaiense)和链状亚历山大藻(Alexandrium catenella)在单一和混合情况下对赤潮藻→卤虫模拟食物链物质传递的影响进行了探讨。结果表明:与其它饵料微藻相比,东海原甲藻必需氨基酸中的苯丙氨酸、赖氨酸和组氨酸含量明显偏低。东海原甲藻单独投喂时,卤虫对其的总物质转化效率随着藻密度的增加呈现先逐渐增加再逐渐降低的趋势。而当不同密度的东海原甲藻分别与一种硅藻小新月菱形藻(Nitzschia closterium)混合投喂时,随东海原甲藻密度的增加,卤虫选择性地增加对东海原甲藻的摄食,而降低对小新月菱形藻的摄食,并且其总物质转化效率逐渐降低。暴露于链状亚历山大藻藻液,卤虫体重减轻,且在其体内未检测到叶绿素a,表明卤虫未摄食该藻。当链状亚历山大藻藻细胞重悬液和去藻过滤液分别与小新月菱形藻或东海原甲藻混合时,卤虫对后两株藻的摄食量和总物质转化效率均有所降低。因此,在大规模赤潮发生时,东海原甲藻和链状亚历山大藻可能分别对浮游动物的营养和存活带来不利影响,并影响物质沿食物链的传递。 相似文献
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研究了东海原甲藻的基本营养组成,并就赤潮密度下的东海原甲藻(Prorocentrum donghaiense)和链状亚历山大藻(Alexandrium catenella)在单一和混合情况下对赤潮藻→卤虫模拟食物链物质传递的影响进行了探讨。结果表明:与其它饵料微藻相比,东海原甲藻必需氨基酸中的苯丙氨酸、赖氨酸和组氨酸含量明显偏低。东海原甲藻单独投喂时,卤虫对其的总物质转化效率随着藻密度的增加呈现先逐渐增加再逐渐降低的趋势。而当不同密度的东海原甲藻分别与一种硅藻小新月菱形藻(Nitzschia closterium)混合投喂时,随东海原甲藻密度的增加,卤虫选择性地增加对东海原甲藻的摄食,而降低对小新月菱形藻的摄食,并且其总物质转化效率逐渐降低。暴露于链状亚历山大藻藻液,卤虫体重减轻,且在其体内未检测到叶绿素a,表明卤虫未摄食该藻。当链状亚历山大藻藻细胞重悬液和去藻过滤液分别与小新月菱形藻或东海原甲藻混合时,卤虫对后两株藻的摄食量和总物质转化效率均有所降低。因此,在大规模赤潮发生时,东海原甲藻和链状亚历山大藻可能分别对浮游动物的营养和存活带来不利影响,并影响物质沿食物链的传递。 相似文献
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It is of interest to document the cytotoxicity and anti microbial analysis of silver and graphene oxide nanoparticles. The plant extracts from Andrographis paniculata and Ocimum sanctum Linn were used as reducing agent. The nanoparticles were characterized using UV-visible spectroscopy, FT-IR, XRD and TEM. The antimicrobial activity was completed for oral pathogens. Brine Shrimp Lethality assay was conducted for cytotoxicity. Thus, we show that silver and graphene oxide bio based nanoparticles have antimicrobial activity with minimum cytotoxic effects. 相似文献
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Avupati VR Yejella RP Guntuku G Gunta P 《Bioorganic & medicinal chemistry letters》2012,22(2):1031-1035
A series of novel diarylsulfonylureas (1-28) have been synthesized and characterized by FTIR, (1)H NMR, (13)C NMR and LC mass spectral analysis. All the synthesized compounds were evaluated for their in vitro cytotoxicity and antimicrobial activities. Among the tested compounds for cytotoxicity using Brine Shrimp Lethality assay, compounds 18 and 22 exhibited significant cytotoxicity at ED(50) values 3.96±0.21 and 4.02±0.19μg/mL, respectively. This level of activity was found comparable to that of the reference drug podophyllotoxin with ED(50) value 3.61±0.17μg/mL and it could be a remarkable starting point to develop new lead molecules with major cytotoxicity. Antimicrobial activity was screened using agar well diffusion assay method against selected Gram-positive, Gram-negative and fungal strains. Most of the compounds showed promising antibacterial and antifungal activity and the activity expressed as the minimum inhibitory concentration (MIC) in μg/mL. 相似文献
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Ajmeri Sultana Shimu Masum Miah Mutasim Billah Sumon Karmakar Sumon Chandro Mohanto Ratna Khatun Md. Abu Reza Kazi Md. Faisal Hoque 《Saudi Journal of Biological Sciences》2021,28(3):2014-2022
Medicinal plant-derived bioactive compounds have recently gained more interest in biological research as an important source of novel drug candidates. Phyllanthus acidus (L.) is a widely distributed herbal medicinal plant naturally used in Ayurvedic medicine in Bangladesh. The present study focused on exploring the biological potential as well as the inhibitory effect of EAC cell growth with a comparative analysis between Phyllanthus acidus fruit pulp and seed. Crude methanol extract of P. acidus (MEPA) fruit pulp and seed was assessed as DPPH and NO free radical scavengers. While Brine Shrimp lethality bioassay, the standard protocol of phytochemical screening and hemagglutination assay were performed successively to determine the toxic effect on normal cells, the identification of some crucial phytochemicals, and the existence of lectin protein. EAC (Ehrlich’s Ascites Carcinoma) cell growth inhibition was determined by hemocytometer and morphological changes of EAC cells were observed by a fluorescence microscope using Swiss albino mice. The IC50 value of MEPA fruit pulp and seed was obtained as 57.159 µg/ml and 288.743 µg/ml respectively where minimal toxic effects on Brine Shrimp nauplii demonstrates that it is a good source of natural antioxidant compounds. Again, MEPA fruit pulp and seed-mediated effective agglutination of mouse blood erythrocyte strongly support the presence of lectin protein. Furthermore, MEPA fruit pulp and seed extract-treated EAC cells showed 65.71% and 28.57% growth inhibition respectively. The fluorescent microscopic examination of EAC cells treated with MEPA fruit pulp has shown more remarkable structural changes in the nucleus than that of seed. Based on the above findings, the present study reveals that MEPA fruit pulp can be considered as a novel biological candidate for the treatment of fatal diseases shortly. 相似文献
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Pharmacological and toxicological activity of Heterophyllaea pustulata anthraquinone extracts 总被引:1,自引:0,他引:1
S.C. Nuez Montoya A.M. Agnese C. Prez I.N. Tiraboschi J.L. Cabrera 《Phytomedicine》2003,10(6-7):569-574
Benzenic extracts from both stems and leaves of Heterophyllaea pustulata showed the most significant activity in vivo in the Brine Shrimp Lethally Test (BST), relative to others of different polarity. They were therefore selected for in vitro antimicrobial activity studies. Bacteriostatic activity against Micrococcus luteus ATCC 9341 was detected, selectively inhibiting both oxacillin-sensitive and -resistant Staphylococcus aureus, among several gram-positive and gram-negative bacterial species tested. Antifungal activity against important opportunist microorganisms and against those involved in superficial mycosis, all from nosocomial origin was also detected. A chemical screening revealed the presence of anthraquinones as major compounds. Among them, we identified damnacanthal, rubiadin, 2-hydroxy-3-methyl anthraquinone, soranjidiol, rubiadin-1-methyl ether, and damnacanthol in the benzenic stem extract. The benzenic leaf extract shows a similar chemical composition, except for damnacanthal, damnacanthol, soranjidiol-1-methyl ether, and 3 anthraquinones whose structures have not yet been elucidated. Acute toxicity studies revealed a low toxicity in mice for the anthraquinonic extracts, as measured in the LD50 value (123 mg/kg body wt. i.v.), and death was not observed at doses of up to 4000 mg/kg body wt. s.c. 相似文献
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Najmus-Saqib Q Alam F Ahmad M 《Journal of enzyme inhibition and medicinal chemistry》2009,24(3):697-701
Primula macrophylla (Primulaceae) is reported as to be useful in asthma, restlessness, insomnia and fish poisoning. Antifungal and toxic activities of crude extract, fractions and a pure isolated compound exhibited statistically significant activities. Excellent antifungal activity was found in the crude extract, benzene and ethyl acetate fractions against T. longifusis and against M. canis with different MIC values. Antileishmanial activity (IC(50) = 50ug/mL) was observed as compared to standard drug Amphotericin B, and cytotoxic activity (LD(50) = 47.919microg/mL) was also found in the chloroform fraction. While pure compound 2-phenylchromone (Flavone) isolated from the chloroform fraction showed good activity (IC(50) = 25microg/mL) against Leishmania and cytotoxicity (LD(50) = 2.0116 microg/mL) in Brine Shrimp experiments. From antileishmanial and cytotoxic activity it can be concluded that 2-phenylchromone is the major compound responsible for these activities. 相似文献
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Preparative RP-HPLC analysis of a methanol extract of the seeds of Centaurea cyanus afforded four indole alkaloids: moschamine, cis-moschamine, centcyamine and cis-centcyamine, the latter two being new natural products. Structures of these compounds were elucidated by comprehensive spectroscopic analyses. General toxicity of the isolates was determined by Brine Shrimp Lethality bioassay. 相似文献
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It is of particular intrigue to synthesize, analyze anti-bacterial, anti-inflammatory activity, cytotoxicity effect of clove and cardamom reinforced zirconium oxide nanoparticles to coat the orthodontic archwires and study its ramifications. Characterization of nanoparticles was done using Transmission electron microscopic analysis (TEM). Antimicrobial activity was assessed using agar well diffusion method. Cytotoxic effect was assessed using Brine Shrimp Assay. Anti-inflammatory activity was completed using Bovine Serum Albumin (BSA). A Digital magnetic stirrer with a hot plate was used to coat orthodontic arch wires such as NiTi and SS. TEM spherical shape was of size 5 -20 nm. Minimal cytotoxicity was observed at 50 µL. Anti-inflammatory property was fair. Antimicrobial activity against Lactobacillus species, streptococcus mutans staphylococcus aureus and Candida albicans was recorded. NiTi and SS showed a colour shift from silver to orange red with a uniform surface coating on wires. Thus, green synthesized zirconium oxide nanoparticles have potent antimicrobial, anti-inflammatory properties with minimal cytotoxicity for further consideration as nano-coatings on orthodontic archwires such as NiTi and Stainless Steel. 相似文献
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Qazi Najmus-Saqib Fiaz Alam Mansoor Ahmad 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):697-701
Primula macrophylla (Primulaceae) is reported as to be useful in asthma, restlessness, insomnia and fish poisoning. Antifungal and toxic activities of crude extract, fractions and a pure isolated compound exhibited statistically significant activities. Excellent antifungal activity was found in the crude extract, benzene and ethyl acetate fractions against T. longifusis and against M. canis with different MIC values. Antileishmanial activity (IC50 = 50ug/mL) was observed as compared to standard drug Amphotericin B, and cytotoxic activity (LD50 = 47.919μg/mL) was also found in the chloroform fraction. While pure compound 2-phenylchromone (Flavone) isolated from the chloroform fraction showed good activity (IC50 = 25μg/mL) against Leishmania and cytotoxicity (LD50 = 2.0116 μg/mL) in Brine Shrimp experiments. From antileishmanial and cytotoxic activity it can be concluded that 2-phenylchromone is the major compound responsible for these activities. 相似文献
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斜纹夜蛾蜕皮激素受体与超气门蛋白的原核表达及活性检测 总被引:1,自引:0,他引:1
双酰基肼类杀虫剂模拟天然蜕皮激素作用影响幼虫蜕皮。昆虫蜕皮激素受体的高度敏感性和专一性要求必须建立新的杀虫活性检测技术, 以适应快速准确和大批量筛选的要求。本研究采用RT-PCR技术, 获取斜纹夜蛾Spodoptera litura蜕皮激素受体(EcR)与超气门蛋白(USP)功能域目的基因, 构建EcR、 USP功能区基因原核表达载体(pEHISEGFPTEV-EcRcde和pEHISEGFPTEV-USPcde)。载体经诱导表达和蛋白纯化, 获得EcR和USP功能区纯化蛋白。在蛋白浓度l mg/mL, 3H-PonA终浓度8 nmol/L的条件下, 采用放射性配基受体结合分析测定了4种药剂(虫酰肼、 呋喃虫酰肼、 抑食肼和灭幼脲)不同浓度下的放射性比活的变化。结果显示: 随着药剂浓度的逐渐增大, 前3种药剂的放射性比活都有不同程度的降低, 其中虫酰肼的放射性比活降低程度最大, 其次是呋喃虫酰肼和抑食肼, 灭幼脲的放射性比活基本无变化。这些结果表明相同条件下虫酰肼比呋喃虫酰肼和抑食肼有更高的杀虫活力, 本研究的方法可对双酰基肼类杀虫剂或者先导化合物进行初步筛选。 相似文献