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61.
62.
Balcer JL DeAmicis CV Johnson PL Klosin J Whiteker GT Rao CS Dai D 《Pest management science》2011,67(5):556-559
BACKGROUND: Tricyclazole is a commercial fungicide used to control rice blast. As part of re‐registration activities, samples of metabolites and process impurities are required. In addition, isotopically labeled tricyclazole samples are also required. RESULTS: Four new compounds related to tricyclazole are reported. An isotopically labeled sample of tricyclazole was prepared that contained two 15N atoms and one 13C atom. Radiolabeled tricyclazole with 14C at the triazole C3 position was also synthesized. A new process impurity in technical tricyclazole was identified and synthesized. A new metabolite of tricyclazole was identified, independently synthesized and characterized by X‐ray crystallography. CONCLUSION: A previously unreported metabolite of tricyclazole has been identified and structurally characterized. In addition, a new process impurity has been identified by independent synthesis. Identification of these new compounds has facilitated the continued registration of this important fungicide. Copyright © 2011 Society of Chemical Industry 相似文献
63.
The marine carotenoid fucoxanthin can be found in marine brown seaweeds, the macroalgae, and diatoms, the microalgae, and has remarkable biological properties. Numerous studies have shown that fucoxanthin has considerable potential and promising applications in human health. In this article, we review the current available scientific literature regarding the metabolism, safety, and bioactivities of fucoxanthin, including its antioxidant, anti-inflammatory, anticancer, anti-obese, antidiabetic, antiangiogenic and antimalarial activities, and its protective effects on the liver, blood vessels of the brain, bones, skin, and eyes. Although some studies have shown the bioavailability of fucoxanthin in brown seaweeds to be low in humans, many studies have suggested that a dietary combination of fucoxanthin and edible oil or lipid could increase the absorption rate of fucoxanthin, and thus it might be a promising marine drug. 相似文献
64.
狗舌草中毒猪血液中吡咯代谢物的测定 总被引:7,自引:1,他引:6
用含 10 %狗舌草的饲料喂猪 144d ,进行了血液S—吡咯测定。染毒后第 8~ 96d ,试验猪血液S—吡咯TLC呈现较为明显的淡紫色斑 ,Rf值在 0 5 6~ 0 78之间 ;在试验的第 8d ,试验猪血液S—吡咯光密度值达 0 0 89± 0 0 0 7OD单位 ,此后一直呈上升趋势 相似文献
65.
海洋放线菌M1D14代谢产物对几种重要植物寄生线虫的抑制作用 总被引:1,自引:0,他引:1
采用梯度稀释法室内测定了海洋放线菌M1D14发酵液代谢产物对南方根结线虫(Meloidogyne incognita)2龄幼虫及其卵、松材线虫(Bursaphelenchus xylophilus)、大豆孢囊线虫(Heterodera glycines)2龄幼虫的毒力,同时还测定了经过高温高压灭菌和0.22μm微孔滤膜过滤的M1D14发酵液对南方根结线虫的毒力。结果表明,海洋放线菌M1D14发酵液代谢产物对南方根结线虫卵的孵化无明显的抑制作用,对南方根结线虫幼虫毒力最强,对松材线虫幼虫毒力次之,对大豆孢囊线虫幼虫的毒力最弱。经过高温高压灭菌和微孔滤膜过滤的M1D14发酵液对南方根结线虫仍有毒力。M1D14杀线虫谱广、效果好、使用成本低,在生产上具有很好的应用前景。 相似文献
66.
药用植物内生真菌是一类重要的微生物资源,能代谢产生多种生物活性物质,本研究从浙江天目山自然保护区银杏Ginkgo biloba中分离获得1株活性菌株TMSF169。通过形态学和ITS rDNA序列分析,鉴定该菌株为团青霉Penicillium commune。发酵粗提物采用正相硅胶柱层析和Sephadex LH-20凝胶柱层析,以紫外光或碘蒸汽显迹,配合活性追踪,从菌株TMSF169发酵液中分离获得1个具抗真菌及除草活性的化合物TMSF169A,通过质谱和核磁共振波谱等技术将其结构鉴定为圆弧菌醛酸(cyclopaldic acid)。活性测试表明,该化合物具有抗菌活性,对鸭跖草Commelina communis,反枝苋Amaranthus retroflexus,马唐Digitaria sanguinalis、空心莲子草Alternanthera philoxeroides、水稻Oryza sativa等植物均具有致病毒性,对芝麻Sesamum indicum和大豆Glycine max不敏感。结果显示菌株TMSF169具有较好的开发应用价值。 相似文献
67.
68.
花椰菜主要生物活性物质及其抗氧化能力分析 总被引:3,自引:2,他引:1
分析了花椰菜不同器官(花球、茎、叶和根)中芥子油苷等主要生物活性物质及其抗氧化能力,发现烯丙基芥子油苷是花椰菜中主要的芥子油苷,不同器官中芥子油苷的组分与含量差异显著,根系中的总芥子油苷、总脂肪类、总芳香类以及烯丙基芥子油苷和4-甲氧基-吲哚-3-甲基芥子油苷的含量均显著高于其他器官,叶片中吲哚类芥子油苷的含量最高,花球中总芥子油苷、烯丙基芥子油苷和吲哚-3-甲基芥子油苷含量次之,茎中的总芥子油苷含量最低;叶片中的叶绿素、类胡萝卜素、维生素C和多酚含量及抗氧化能力显著高于其他器官。这些结果表明花椰菜的叶片和根系中生物活性物质含量丰富,具有进一步开发和综合利用潜力。 相似文献
69.
本试验研究了"双低"菜籽粕中添加植酸酶、木聚糖酶、β-葡聚糖酶、果胶酶、纤维素酶等非淀粉多糖酶对"双低"菜籽粕中矿物质和干物质、能量代谢率的影响,以及各种酶制剂的适宜添加水平.试验结果表明添加植酸酶、木聚糖酶、β-葡聚糖酶、果胶酶可以改善"双低"菜籽粕中钙、总磷、植酸磷、铁、锌、锰以及干物质和能量的代谢率,并且随着酶制剂的添加量增加,"双低"菜籽粕中干物质和矿物质的代谢率得到改善的幅度也越大. 相似文献
70.
Associations between different organisms have been extensively described in terrestrial and marine environments. These associations are involved in roles as diverse as nutrient exchanges, shelter or adaptation to adverse conditions. Ascidians are widely dispersed marine invertebrates associated to invasive behaviours. Studying their microbiomes has interested the scientific community, mainly due to its potential for bioactive compounds production—e.g., ET-73 (trabectedin, Yondelis), an anticancer drug. However, these symbiotic interactions embrace several environmental and biological functions with high ecological relevance, inspiring diverse biotechnological applications. We thoroughly reviewed microbiome studies (microscopic to metagenomic approaches) of around 171 hosts, worldwide dispersed, occurring at different domains of life (Archaea, Bacteria, Eukarya), to illuminate the functions and bioactive potential of associated organisms in ascidians. Associations with Bacteria are the most prevalent, namely with Cyanobacteria, Proteobacteria, Bacteroidetes, Actinobacteria and Planctomycetes phyla. The microbiomes of ascidians belonging to Aplousobranchia order have been the most studied. The integration of worldwide studies characterizing ascidians’ microbiome composition revealed several functions including UV protection, bioaccumulation of heavy metals and defense against fouling or predators through production of natural products, chemical signals or competition. The critical assessment and characterization of these communities is extremely valuable to comprehend their biological/ecological role and biotechnological potential. 相似文献