Effects of the new antifungal antibiotic mucidin

The antibiotic activity of the antifungal substance mucidin was compared with the activity of nystatin and pimaricin. The antibiotics were tested by the plate method using 19 fungal species, mainly phytopathogenic ones. Toward 14 species, mucidin was ten times more active than nystatin and pimaricin, toward 5 species the activities were roughly the same. The antibiotics differed also in the sharpness of the inhibition zone boundaries.     

Effects of the new antifungal antibiotic mucidin

The morphological changes in 19 fungal species (16 filamentous fungi and 3 yeasts) caused by the antifungal antibiotic mucidin (trade mark Mucidermin Spofa) were examined. The filamentous fungi showed an undulation and ramification of hyphae and thickening of cells. The yeastCandida pseudotropicalis changes the shape and size of cells and the structure of cytoplasm.     

A new antifungal antibiotic produced byStreptomyces galbus

A streptomycete producing an antibiotic having antifungal and antibacterial activity was isolated from a soil sample of West Bengal. It was characterized and identified as Streptomyces galbus. The antibiotic was isolated from the fermented broth by treatment with activated charcoal and purified by chromatography on alumina and paper. It is a colourless, odourless, hygroscopic, amorphous compound. Although homogeneous by paper and thin-layer chromatography, the possibility of the presence of two components was indicated by gel filtration. Its physico-chemical characteristics and UV-absorption spectrum suggest a non-polyenic nature. It is active against a wide variety of fungi and bacteria. It has some phytotoxic effect, but is relatively non-toxic to rats.     

HM17, a new polyene antifungal antibiotic produced by a new strain of Spirillospora

H. HACÈNE, K. KEBIR, D. SID OTHMANE AND G. LEFEBVRE. 1994. An antifungal antibiotic (HM17) was obtained from a new isolate classified to the genus Spirillospora on the basis of its chemical and morphological properties. On solid media this antibiotic strongly inhibited the growth of strians of Fusarium oxysporum formae speciales albedinis, Botrytis cinerea, Gaeumaniomyces graminis and several other fungi known to be plant and human pathogens. Antifungal activity in culture collection strains of Spirillospora has not so far been reported. The u.v. absorption spectrum and physico-chemical characteristics place HM17 in the methylpentaene sub-group of polyene macrolides. HM17 is different from other known methylpentaenes. This is the first report of polyene production by a Spirillospora.     

AH7, a non-polyenic antifungal antibiotic produced by a new strain of Streptosporangium roseum

An antibiotic (AH7) produced by Streptosporangium roseum strain 214 was investigated. This compound was extracted with chloroform from the filtrate culture and purified using thin-layer chromatography and high pressure liquid chromatography procedures. The antibiotic strongly inhibited the growth of several strains of fungi and bacteria known to be plant and human pathogens. This compound differed from all other antibiotics known to be synthesized by Streptosporangium spp. Some of its chemical and physical properties resembled those of maytansines produced by Nocardia but the antibiotic AH7 has only antibacterial and antitumoral activities.     

Lysis of growing fissin-yeast cells induced by aculeacin A,a new antifungal antibiotic

Cells of Schizosaccharomyces pombe grown in the presence of aculeacin A, a peptide antibiotic, were lysed resulting the death of cells. Under high osmolarity, the cellular lysis induced by aculeacin A was considerably reduced. The use of synchronous-culture systems distinguished cell elongation from cell division revealed that the sites of aculeacin A-induced lysis on the fission yeast were the end(s) and the cell plate region, corresponded to the regions of the cell wall synthesis. Aculeacin A-resistant survivors exhibited morphological alterations which were swollen at one or both ends of the cell and appeared drumstick or dumbbel like; the wall of the bulge region was observed to be stained with a fluorescent brightener, as well as that of the cell plate region. These effects of aculeacin A are discussed as compared with effects of 2-deoxy-D-glucose.     

Isolation and structure elucidation of a new antifungal and antibacterial antibiotic produced by Streptomyces sp. 201

An antibacterial and antifungal antibiotic was isolated from the culture filtrate of Streptomyces sp. 201, and its structure was determined as 2-methyl-heptyl isonicotinate by extensive use of NMR spectroscopy. The compound exhibited marked antimicrobial activity against Bacillus subtilis, Shigella sp., Klebsiella sp., E. coli, Proteus mirabilis, and the pathogenic fungi, Fusarium moniliforme, F. semitectum, F. oxysporum, F. solani and Rhizoctonia solani.