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101.
DusaneeThanaboripat KowitNontabenjawan KwanruenLeesin DetchpolTeerapiannont OrataiSukcharoen RararatRuangrattanamatee 《林业研究》1997,(1)
INTRoDUCTIONANatoxinsarctoxicsccondarymctabolitCspro-ducedbyAsPergillus~s,A.parastticusandA.nomius(Kurbzmanetal,l987).ThescfUngicangrowreadilyonawidevarictyofagriculturalconunoditicsandPoschealthhazardtobothhumanandanimals.ANa-toxinsareacutClytoxic,carcin… 相似文献
102.
103.
104.
105.
Zhanping Sun Yushan Li Da-qing Jin Ping Guo Haibin Song Jing Xu Yuanqiang Guo Lei Zhang 《Fitoterapia》2012
A phytochemical investigation of the whole plants of Ajuga decumbens led to the isolation of three new (1, 2a, and 2b) and three known (3a−3c) neo-clerodane diterpenes. Their structures were elucidated by spectroscopic data analysis (IR, ESIMS, HR-ESIMS, 1D and 2D NMR), and the structure of 1 was confirmed by X-ray crystallography. The inhibitory activities on LPS-induced NO production of the six diterpenes were evaluated and compounds 2a, 2b, and 3a showed inhibitory effects. 相似文献
106.
Antimicrobial peptides expressed on different epithelial lining are major components of the innate immune system. Based on
the deduced amino acid sequence of Bubalus bubalis lingual antimicrobial peptide (LAP) cDNA (Accession No. DQ458768), five overlapping peptides LAP23–55, LAP42–64, LAP21–64, LAP1–26 and LAP1–64 were synthesized using solid phase fluorenylmethoxycarbonyl (Fmoc) chemistry. Circular Dichroism spectroscopy of synthesized
peptides revealed predominantly β-structure for LAP23–55, LAP42−64 and LAP21–64 with less α-helix in different solutions. Quantitation of secondary structure indicated the highest β-structure for all these
three peptides in membrane mimetic SDS solution. The helicogenic solvent TFE could not induce helix in LAP23–55 however TFE induced helical propensity was observed in LAP42–64 and LAP21–64. The quantitation of secondary structure indicated the highest ordered structure for LAP23–55 followed by LAP42–64 and LAP21–64. The antibacterial activity of LAP23–55 was found to be more potent against Staphylococcus aureus, Listeria monocytogens, Escherichia coli and Salmonella typhimurium followed by LAP42–64 and LAP21–64. Minimum inhibitory concentration (MIC) also showed similar trend with lowest value for LAP23–55 followed by LAP42–64 and LAP21–64. Haemolysis and cytotoxicity was observed above 3 fold for LAP21–64, above six fold for LAP23–55 and LAP42–64 of their MIC. The LAP1–26 and LAP1–64 could not produce any characteristic CD spectra and did not show any antimicrobial activity, indicating that N- terminal
of the peptide negates the antimicrobial activity. 相似文献
107.
本研究采用平板对峙法和菌丝块法测定分离自广西北部湾的3株海洋真菌MF-3、MF-6和MF-13的抗荔枝和水稻病原菌抗菌活性,并通过形态学观察结合分子生物学方法鉴定其分类地位。结果表明,当采用平板对峙法时,3株海洋真菌对荔枝霜疫霉、炭疽病菌、水稻纹枯病菌和水稻稻瘟病菌等4种指示菌的菌丝生长均有强的抑制作用;菌丝块法试验结果发现3株真菌的发酵液均对荔枝霜疫霉菌有很好的抑制效果,菌丝相对生长抑制率分别达到94.29%、98.16%和86.37%,对水稻纹枯病病原菌抑制效果次之,其菌丝相对生长抑制率达到80%左右;其中,MF-3菌株对荔枝霜疫霉、炭疽菌、水稻纹枯病菌和水稻稻瘟病菌都有较好的抑制作用,MF-6对霜疫霉、水稻纹枯病菌和水稻稻瘟病菌也有较好的抑菌效果和广谱性。结合形态学观察和ITS rDNA序列比对分析,初步将MF-3鉴定为布雷正青霉(Eupenicillium brefeldianum),MF-6为微紫青霉(Penicillium janthinellum),MF-13为短棒曲霉(Aspergillus clavatonanicus)。耐盐度试验结果表明这3株真菌是适应海洋环境的兼性海洋真菌。该3株海洋真菌表现的抗真菌活性,对应用于荔枝或水稻病害的生物防治和新型农药的研发有潜在的应用价值。 相似文献
108.
本文通过对人工制备的不同盐浓度的盐渍土的抗剪强度及其指标进行研究发现:随着土样中可溶性盐浓度的增加,土的粘聚力约呈线性下降的趋势,内摩擦角近似呈线性上升趋势.土样中的可溶性盐浓度在不同范围内变化时,其抗剪强度的变化趋势分别由粘聚力或内摩擦角决定.土祥的可溶性盐浓度与土样的抗剪强度、粘聚力、内摩擦角之间存在非常强的函数关系. 相似文献
109.
Li-Ben JiangKei-Fei Zhao Dong-Ju WangJin-Cai Wu 《Pesticide biochemistry and physiology》2012,102(1):51-55
Jinggangmycin is an antibiotic fungicide against the rice sheath blight, Rhizoctonia solani, in China. Previous investigations have shown that jinggangmycin leaf spray stimulated the fecundity of Nilaparvata lugens Stål (Hemiptera:Delphacidae), but the effects of different application methods and concentrations of jinggangmycin on the reproduction of N. lugens have not been investigated. Here, we investigated three treatment methods (foliar and stem sprays and topical treatment) and four concentrations (100, 200, 400 and 800 ppm) of jinggangmycin on the reproduction of adult female N. lugens. The results showed that leaf spray significantly stimulated the fecundity of N. lugens and increased the vitellin content in female ovaries and the gene expression level of vitellogenin (Nlvg), but there was no significant effect on reproduction found for stem spray. In four concentrations of jinggangmycin, leaf sprays at concentrations of 100, 200 and 400 ppm and topical treatments of 100 and 200 ppm significantly increased the number of eggs laid, the vitellin content and the gene expression level of Nlvg compared to the control. Therefore, we suggest that stem spray at high concentration should be applied (if possible) when jinggangmycin is used against rice sheath blight to facilitate harmonious control of rice pests. 相似文献
110.
在一定范围内,使用高浓度噻苯隆,会直接导致莴笋的功能叶、幼叶受害,同时会因为代谢导致新生叶片受害。在摘除死亡叶片后,正常管理下,莴笋植株可恢复生长,最终成熟;使用高浓度(〉0.10%)噻苯隆,会使成熟莴笋植株的株高、茎粗、叶片质量、叶中脉质量、叶片长宽比、根部质量、产量下降,而叶面积指数、品质提高;使用低浓度(0.05%)噻苯隆,可提高莴笋植株的叶片质量、叶中脉质量、茎部质量、株高、茎粗、产量。 相似文献