• Microbiology and Biotechnology Letters
• /
• v.21 no.4
• /
• pp.322-328
• /
• 1993

During the screening of antifungal compounds from microbial secondary metabolites to control phytophthora blight of red pepper caused by Phytophthora capsici, a soil isolate, strain 38D10 was selected. Based on taxonomic studies, this strain was identified as Streptomyces neyagawaensis. The antifungal compound was purified from culture broth by HP-20 column chromatography, ethyl acetate extraction, silica gel column chromatography, HPLC and identified as concanamycin B by UV. $^1H$-NMR, $^{13}C$-NMR, SIMS analysis. Concanamycin B has strong antifungal activity against some phytopathogenic fungi but not antivacterial activity and preventive value were 50% and 100% at 125ppm and 250ppm in pot assay.

• Microbiology and Biotechnology Letters
• /
• v.22 no.4
• /
• pp.368-372
• /
• 1994

Three more unusual macrolides in addition to concnamycin B were isolated from the mycelium of Streptomyces sp. strain Bal6. These four compounds showed a potent cytotoxity to hunian cancer cell lines, SNU-1 (stomach cancer cell line), SNU-354 (liver cancer cell line), MCF- 7 (breast cancer cell line) and KB-3-1 (oral epidermoid carcinoma cell line). Interestingly, these compounds confered slight differential cytotoxity on RHEK-1, a human epidermal keratinocyte cell line immotalized by AD12-SV40 hybrid virus and RHEK-1/pSV$_{2}$ ras which was resulted from H-ras transfomation of RHEK-1. These compounds were determined to be concanamycin A, conca- namycin E and 0-methyl concanamycin B by NMR and other spectral analysis.

• Microbiology and Biotechnology Letters
• /
• v.21 no.4
• /
• pp.316-321
• /
• 1993

MCH-201 was isolated from the mycelium of Streptomyces sp. Ba16 as a potent effector on proliferation and morphology of human breast tumor cell line, MCF-7. Morphological change could be observed at concentration between 2.5${\mu}$g/ml and 250pg/ml and showed cytotoxic effect at the concentration of more than 5${\mu}$g/ml. This compound also showed inhibitory effect on DNA synthesis of hepatoma cells, Hepa 1c1c7, and strong cytotoxic effect on proliferation of human tumor cell lines, A549 and XF498.