硅酸盐细菌代谢产物对植物生长的促进作用

从根际微生物的角度研究了硅酸盐细菌对植物生长的促进作用。代谢产物对植物生长促进作用最好的是１３８＃菌,处理５０天,水稻株高比对照增加２７．７％,生物量比对照增加４０．２％,硅酸盐细菌的代谢产物对植物生长的刺激作用与浓度有关,低浓度的代谢产物对植物生长有明显的促进作用,高浓度的代谢产物则有一定的抑制作用,代谢产物的作用对根系生长的影响尤为明显。     

丁硫克百威在韭菜和土壤中的残留动态研究

通过大田试验及气相色谱分析,研究了丁硫克百威在韭菜和土壤中的残留动态。结果表明,丁硫克百威在韭菜中的残留半衰期为1.5d,在土壤中,未能检测出丁硫克百威残留。按推荐剂量750mL·hm-2和2倍剂量1500mL·hm-2施用丁硫克百威20%乳油,使用3次,采样距最后一次施药间隔期14d时,丁硫克百威及其代谢物在韭菜和土壤中的残留量分别为0.026mg·kg-1、未检出和0.097mg·kg-1、未检出。     

稀土在组织及细胞培养上的应用研究进展

概述了近10a来稀土在组织及细胞培养上的应用研究进展.稀土能促进试管苗的分化、生长、生根及发育;促进愈伤组织诱导、生长及细胞的生长;对体细胞胚的发生有一定促进作用;促进次生代谢物的合成及释放.并对稀土在此方面的作用机理作了初步的探讨.     

Synthesis of new compounds related to the commercial fungicide tricyclazole

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     

Fucoxanthin, a marine carotenoid present in brown seaweeds and diatoms: metabolism and bioactivities relevant to human health

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.     

狗舌草中毒猪血液中吡咯代谢物的测定

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     

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

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。     

一株银杏内生真菌的鉴定及其活性代谢产物研究

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。     

植物次生代谢物的自毒作用及其与连作障碍的关系

连作障碍问题的发现已有上千年的历史,但对其发生机理和克服措施还没有取得突破。本文分析了植物次生代谢物的种类及其产生机理、次生代谢物的自毒作用、植物对自产的次生代谢有毒物质的抗性机制及其形成时序等,认为次生代谢物对新生植物的自毒作用是连作障碍发生的关键因素之一,并在此基础上提出了克服连作障碍的几种途径。