广西买麻藤属两新种

广西买麻藤属两新种邵宏（北京医科大学生物遗传教研室,北京１０００８３）关键词球子买麻藤;巨子买麻藤;新种ＴＷＯＮＥＷＳＰＥＣＩＥＳＯＦＧＮＥＴＵＭＬ．ＦＲＯＭＧＵＡＮＧＸＩ￥ＳｈａｏＨｏｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＢｉｏｌｏｇｙａｎｄＧｅｎｅｔｉｃ...     

Nucleotide status and protein synthesis in vivo in the apices of juvenile and mature Sequoiadendron giganteum during budbreak

Adenine and guanine nucleotide contents of isolated apices collected from a juvenile and a mature clone of Sequoiadendron giganteum (Lindl.) Buchholz during budbreak were determined. GDP and GTP contents were significantly higher in the juvenile clone apex than in the mature ones, whereas there was no difference in ATP concentration between the two materials. In vivo, induction of protein synthesis was similar in the two clones after 10 min of [³⁵S]-methionine labeling. The increase of [³⁵S]-methionine-tRNAs and labeled proteins continued up to 30 min for the juvenile clone. They markedly declined for the mature clone after 10 min. Only the diminution of this in vivo protein synthesis was well correlated with a decrease in GTP content.     

暖地大叶藓化学成分的研究

从真藓科大叶藓属植物暖地大叶藓Rhodobryum giganteum(schwaegr.)Par.的乙醇提取物中分离得到9个化合物,通过波谱分析鉴定其分别为麦角甾-7,22-双烯-3β,5α,6β-三醇(1),乌苏酸(2),琥珀酸(3),尿嘧啶(4),棕榈酸(5),槲皮素(6),碳二十九烷(7),β-谷甾醇(8),胡萝卜苷(9).化合物1～9均为首次从该植物中分离得到.     

松茸组织分离物的rDNA-ITS序列鉴定

以采自云南丽江的松茸子实体为材料,进行组织分离后,利用一对ITS引物(ITS1-ITS4)对子实体(SR176B,SR172B)和分离物(SR176H,SR172H)进行了PCR扩增、琼脂糖凝胶电泳分析,得到了700bp左右的扩增条带,进一步对ITS序列进行同源性检索比对,结果表明SR176H与SR176B,SR172H与SR172B序列同源性均为100%,鉴定出该分离物就是松茸的纯培养物。     

Metabolism of Aromatic Amino Acids in Microorganisms

It was found that when Rhodotorula rubra IFO 0911 was grown in a phenylalanine medium, benzoic acid and p-hydroxybenzoic acid besides cinnamic acid were formed in the cultured both. The conversions of cinnamic acid into benzoic acid and of benzoic acid into p-hydroxybenzoic acid, and the degradation of p-hydroxybenzoic acid were demonstrated in intact cells of Rhodotorula rubra. These activities were observed in the cells grown on various media, including the medium containing no phenylalanine, and were found to be distributed widely in Rhodotorula. The cells of Rhodotorula rubra were also able to degrade p-coumaric acid, 3,4-dihydroxybenzoic acid (protocatechuic acid), p-hydroxyphenyl-acetic acid, 3-methoxy-4-hydroxycinnamic acid (ferulic acid) and 3-methoxy-4-hydroxybenzoic acid (vanillic acid). From these results, the metabolic pathways for phenylalanine and tyrosine in Rhodotorula were discussed.     

独角莲超临界萃取物的GC-MS分析及体外抑瘤活性

为了寻找独角莲抗肿瘤的活性物质基础和合理开发利用独角莲,本研究采用超临界CO₂萃取方法提取独角莲块茎粉,通过气相色谱—质谱技术对提取物进行成分鉴定。并采用噻氮唑蓝比色法（MTT）测试萃取物的体外抑瘤活性。结果：从独角莲的超临界CO₂萃取物中检出37种物质,含量最丰富的4种化合物为：β-谷甾醇（β-Sitosterol）,占40.22%;菜油甾醇（Campesterol）,占18.45%;棕榈酸（n-Hexadecanoic acid）,占9.52%;亚油酸（9,12-Octadecadienoic acid (Z,Z)-）,占8.15%。MTT实验证明萃取物对结肠癌HCT-8、卵巢癌HO-8910、胃癌SGC-7901、肝癌SMMC-7721均有显著的抑制作用,其中肝癌SMMC-7721细胞对萃取物最为敏感。独角莲块茎超临界CO₂萃取物有显著抑瘤活性,针对该萃取物的进一步分离分析对其活性物质基础的寻找具有重要意义。     

Genetic relationship of Tricholoma matsutake and T. nauseosum from the Northern Hemisphere based on analyses of ribosomal DNA spacer regions

The genetic relationship among Tricholoma matsutake and T. nauseosum strains collected from various parts of the Northern Hemisphere was investigated using sequence analysis of the rDNA ITS region and PCR-RFLP analysis of the rDNA IGS-1 region. ITS sequence similarity between T. matsutake and T. nauseosum ranged between 98.1% and 100%. The strains of T. matsutake from coniferous forests and those from broad-leaved forests showed more than 99.8% similarity in their ITS sequences. Three distinct RFLP types were detected when IGS-1 regions were digested with Cfr13I. RFLP patterns showed no variability among the strains of T. nauseosum and those of T. matsutake from broad-leaved forests. This pattern corresponded to the dominant RFLP type in the Japanese population of T. matsutake. Thus, strains belonging to this RFLP type are widely distributed throughout East Asia and Europe and associated with many tree species of Pinaceae and Fagaceae. The result suggests that T. matsutake in coniferous and broad-leaved forests and T. nauseosum should be treated as the same species genetically.     

Plant growth regulators from the fruiting bodies of Tricholoma flavovirens

A novel indole derivative (1) and three known compounds (2–4) were isolated from the fruiting bodies of Tricholoma flavovirens. Their structures were determined or identified by the interpretation of spectroscopic data. Compounds 1 and 2 promoted root growth of lettuce and inhibited hypocotyl growth at 1 μmol/paper. Compound 3 inhibited hypocotyl and root growth at 100 nmol/paper.     

Purification and some properties of Α-amylase from an ectomycorrhizal fungus, <Emphasis Type="Italic">Tricholoma matsutake</Emphasis>

-Amylase from a still culture filtrate of Tricholoma matsutake, an ectomycorrhizal fungus, was isolated and characterized. The enzyme was purified to a homogeneous preparation with Toyopearl-DEAE, gel filtration, and Mono Q column chromatography. The -amylase was highly purified (3580 fold) with a recovery of 10.5% and showed a single protein band by SDS-PAGE. The enzyme was most active at pH 5.0–6.0 toward soluble starch and stable within the broad pH range 4.0–10.0. This -amylase was a relatively thermostable enzyme (optimum temperature, 60°C; thermal stability, 50°C). The molecular mass was 34kDa by size-exclusion chromatography and 46kDa by SDS-PAGE. This enzyme was not inhibited by the Hg²⁺ ion. Measurement of viscosity and TLC and HPLC analysis of the hydrolysates obtained from amylose showed that the amylase from T. matsutake is an endo-type (-amylase). Substrate specificity was tested using amylose with different polysaccharides. This -amylase readily hydrolyzed the -1,4 glucoside bond in soluble starch and amylose A (MW, 2900), but did not hydrolyze the -1,6 bond and cyclic polysaccharides such as - and -cyclodextrin.