吸水链霉菌、放线菌Sp.253和金色毛壳菌的次生代谢产物研究

链霉菌是十分重要的一类放线菌，绝大多数的抗生素都由该类细菌产生。毛壳属真菌是一类重要的丝状真菌，从中也发现有很多结构新颖、活性独特的活性物质。因此本论文对两株链霉菌的活性成分及一株金毛壳菌的次生代谢产物进行了研究。 1．从吸水链霉菌（Streptomyces hygroscopicus 1.358）液态发酵产物（乙酸乙酯提取物）中分离得到3个化合物，通过波谱方法鉴定为RK955A (1)、Nigericin（2）、Elaiophylin（3）。以青霉素耐药-金黄色葡萄球菌作为指示菌的抗菌活性测定表明，三者均具有较强抗菌活性。 2．通过抗肿瘤体外活性筛选模型筛选得到得到一株链霉属土壤放线菌，从中分离得到六个化合物：苯乙酰胺（4）、苯丙酰胺（5）、肉桂酰胺（6）、3-（N-（甲酰胺基）乙酰基）吲哚（7）、鸟苷磷酸（8）、鸟苷（9）。 3．从金色毛壳菌（Chaetomium aureus）的固态培养物中分离得到13个化合物，利用波谱方法将其鉴定为：金毛壳菌素A（10）、金毛壳菌素B（11）、Eugenetin（12）、Eugenitol（13）、Chaetoquadrin A（14）、Chaetoquadrin B（15）、Chaetoquadrin G（16）、Chaetoquadrin H（17）、Chaetochromin A（18）、Sterigmatocystin（19）、O-methylsterigmatocystin（20）、3β-羟基-麦角甾-5，7，22-三烯（21）和过氧麦角甾醇（22）。 4．综述了聚醚类抗生素的结构、生物合成、生物活性及作用机理。 The genus Streptomyces (Actinomycetes) is an important group of microbe. Most antibiotics known nowdays are discovered from species of Streptomyces. The fungi of the genus Chaetomium have attracted much attention because various kinds of secondary metabolites with diverse bioactivities have been found from them. Thus, the bioactive compounds from two strains of Streptomyces and the secondary metabolites of Chaetomium aureus were investigated. 1. Three compounds were isolated from the ethyl acetate extract of the fermentation broth of Streptomyces hygroscopicus. They are identified to be elaiophylin (1), nigericin (2), and antibiotic RK955A (3) on the basis of their spectroscopic data. Compounds 1-3 possess antibacterial activities against Staphyloccocus aureus. 2. It was found that the extract of the fermented broth of a strain of Actinomycetes could inhibit some tumor cel lines. Separation of the bioactive fraction led to the isolation of six compounds. They were characterized to be phenylacetamide (4), phenylpropylamide (5), trans-cinnamamide (6), 3- (N- (formylmethyl) acetamide) indole (7), guanylicacid (8), and guanosine (9). 3. From the fermented broth of Chaetomium aureus, 13 compounds were isolated for the first time. They were determined to be chaetomiumycin A (10), chaetomiumycin B (11), eugenetin (12), eugenitol (13), chaetoquadrin A (14), chaetoquadrin B (15), chaetoquadrin G (16), chaetoquadrin H (17), chaetochromin A (18), sterigmatocystin (19), O-methylsterigmatocystin (20), 3β-hydroxyergosta-5, 7, 22-triene (21) and peroxy-ergosterol (22). Compounds 10 and 11 are new ones. 4. Structure, biosynthesis, biological activity, and mechanisms of polyether antibiotics were reviewed.

固定化微生物降解土壤中菲和芘的研究

Immobilized with PVA,sodium alginate and activated carbon,both Zoogloea sp. and Fusarium sp.strains could degrade phenanthrene and pyrene efficiently.The optimal carrier was made of 100ρ·g -1 L PVA,5 sodium alginateρ·g -1 L and 50 activated carbon ρ·g -1 L.The degradation rates of phenanthrene and pyrene in 10 days were 87.48% and 75.34% by the immobilized bacterium,37.04% and 20.85% higher than those by the free bacterium,and the rates in 15 days were 84.36% and 74.87% by the immobilized fungus,5.35% and 11.23% higher than those by the free fungus.

莲藕状固定化真菌(镰刀菌)对土壤中菲、芘的降解

采用莲藕状聚乙烯醇复合载体对镰刀菌(Fusarium sp.)固定化包埋,分别进行了不同接种量的固定化真菌对菲、芘的降解,固定化真菌对不同系列浓度菲、芘的降解试验,以及对固定化真菌在自然土壤中对菲、芘降解的各项参数作了测定,结果表明,固定化真菌具有较好的降解效果,同时用电镜观察研究了镰刀菌在固定化载体中的分布形态.自然土壤中固定化真菌在360h时,对菲、芘的降解效率分别为76.96%和20.69%,而土著菌仅达到33.37%和15.28%.

杉木连栽根际土壤致害Fusariumoxysporum拮抗菌的筛选

尖孢镰刀菌萎蔫专化型(Fusarium oxysporumf.sp.vasinfectum,SF2)及其分泌的毒素是造成杉木连栽土壤中毒的重要因素之一,基于此,笔者从106株海洋微生物中筛选到23株具有拮抗SF2特性的菌株,在湖南会同杉木中心产区进行的室外盆栽试验结果表明,其中海洋细菌3728菌株能够在杉木根际土壤中定殖,抑制杉木致害菌的生长繁殖,促进了杉木幼苗生长,经鉴定为枯草芽孢杆菌(Bacillus subtilis)。该研究对杉木人工林生产具有重要的理论与实践意义。

Methyleneimidazoline Complexes of Iridium, Rhodium, and Palladium from Selective C(sp(3))-H Bond Activation

Palladium, iridium, and rhodium complexes of 2-methyleneimidazolines have been synthesized by selective phosphine-assisted activation of the 2-methyl C-H bonds in 2-methylimidazolium compounds. Metallacycles of various sizes were obtained in the reaction of phosphine-tethered 2-methylimidazolium compounds and [{M(cod)X}(2)] (M = Rh or Ir cod = 1,5-cyclooctadiene: X = alkoxyl or Cl). representative complexes were characterized by X-ray crystallography. The selectivity for aliphatic C(sp(3))H versus aromatic C(sp(2))H activation could be adjusted by means of the steric bulk of the OR ligand, whereby a bulky, OR group favors activation of the 2-methyl C(sp(3))-H bond. Experimental results confirmed that a methyl C-H activation product (a seven-membered iridacycle) is the kinetic product, while the aryl C-H activation product (a six-membered iridacycle) is the thermodynamic product.

High resolution mass spectrometric alveolar proteomics: Identification of surfactant protein SP-A and SP-D modifications in proteinosis and cystic fibrosis patients

In the present study, one- and two-dimensional gel electrophoresis combined with high resolution Fourier transform-ion cyclotron resonance mass spectrometry (FT-ICR MS) have been applied as powerful approaches for the proteome analysis of surfactant proteins SP-A and SP-D, including identification of structurally modified and truncation forms, in bronchoalveolar lavage fluid from patients with cystic fibrosis, chronic bronchitis and pulmonary alveolar proteinosis. Highly sensitive micro preparation techniques were developed for matrix-assisted laser desorption/ionization (MALDI) FT-ICR MS analysis which provided the identification of surfactant proteins at very low levels. Owing to the high resolution, FT-ICR MS was found to provide substantial advantages for the structural identification of surfactant proteins from complex biological matrices with high mass determination accuracy. Several protein bands corresponding to SP-A and SP-D were identified by MALDI-FT-ICR MS after electrophoretic separation by one- and two-dimensional gel electrophoresis, and provided the identification of structural modifications (hydroxy-proline) and degradation products.