Chitin and chitosan were extracted from mycelial biomass of Cunninghamella elegans and the performance for copper, lead and iron biosorption in aqueous solution was evaluated. The growth curve of C. elegans was accomplished by determination of biomass, pH, glucose and nitrogen consumption. Chitin and chitosan were extracted by alkali-acid treatment and the yields were 23.8 and 7.8%, respectively. For the adsorption analysis, the process of heavy uptake metal sorption was evaluated using polysaccharides solutions (1% w/v). The rate of metallic biosorption was dependent upon the concentration and pH of metal solutions, and the best results were observed with pH 4.0. Chitosan showed the highest affinity for copper and chitin for iron adsorption. The results suggest that C. elegans (IFM 46109) is an attractive source of production of chitin and chitosan, with a great potential of heavy metals bioremediation in polluted environments.
A new antibiotic, leucinostatin, was isolated from the culture filtrate of Fenicillium lilacinum. The antibiotic was obtained in the form of white prisms, decomposing at 131~136°C, and showing optical rotation [^]d2+644°(c 0.5, methanol). The ultraviolet absorption spectrum showed only an inflection at 220nm in methanol. The antibiotic gave a positive reaction to biuret and negative to ninhydrin. Upon hydrolysis, it gave a positive reaction to ninhydrin, yielded leucine predominantly, and the peptide nature of the antibiotic was assumed. Leucinostatin was found to be active against some gram-positive bacteria and a wide range of fungi. It was also cytotoxic to HeLa cell culture and showed some inhibitory effect on Ehrlich subcutaneous solid tumor. The
Three new coupling compounds derived from citrinin (9) and 2,3,4-trimethyl-5,7-dihydroxy-2,3-dihydrobenzofuran (8) -penicitrinone A (1), penicitrinol A (2) and penicitrinone B (3) -and a new citrinin derivative -decarboxydihydrocitrinin (4) -were isolated along with 3-methoxy-1-methyl-4(1H)-quinolone (5), quinolactacin A2 (6), dihydrocitrinone (7), 2,3,4-trimethyl-5,7-dihydroxy-2,3-dihydrobenzofuran (8), citrinin (9), quinocitrinin A or B (10), and decarboxydihydrocitrinone (11) from the extract of Penicillium citrinum IFM 53298. The relative structures of compounds 1-4 were confirmed on the basis of spectroscopic investigations and chemical correlations. Citrinin (9) and quinolactacin A2 (6) both showed antifungal activity.
The nucleotide sequences of the D1/D2 domains of large subunit (26S) ribosomal DNA for 76 strains of 46 species of pathogenic dematiaceous fungi and related taxa were determined. Intra-species sequence diversity of medically important dematiaceous fungi including Phialophora verrucosa, Fonsecaea pedrosoi, Fonsecaea compacta, Cladophialophora carrionii, Cladophialophora bantiana, Exophiala dermatitidis, Exophiala jeanselmei, Exophiala spinifera, Exophiala moniliae, and Hortaea werneckii were extremely small; as few as 0 changes were detected in C. bantiana, Fonsecaea and Exophiala species, 1 bp in C. carrionii and H. werneckii, and 2 bp in P. verrucosa. Inter-species nucleotide diversity between most species was higher. These data suggested that the D1/D2 domain is sufficiently variable for identification of pathogenic dematiaceous fungi and relevant species. The phylogenetic trees constructed from the sequence data revealed that most human pathogenic species formed a single cluster and that Cladosporium and Phialophora species were distributed polyphyletically into several clusters.
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