title: [Mechanism of polyene antibiotic inactivation. Possible ways for levorin stabilization].
abstract: Various means for levorin isolation were studied with the EPR method and approaches to stabilization of the antibiotic on storage under natural conditions were discussed. It was shown that formation of the radicals begins already at the first stage of the antibiotic isolation, i.e. during extraction from the mycelium. Treatment of the solvents with an inert gas or addition of antioxidants decreased the number of free radicals in a freshly isolated product. The antibiotic inactivation rate depended on the initial concentration of the free radicals and conditions of natural storage. The levorin stability increased when oxygen was thoroughly removed from the solvents at all isolation stages and the antibiotic was subsequently stored under conditions preventing any access of the air. The stabilizing effect was also observed when the oxidative effect of the amino sugar moiety on destruction of the polyenic chromophore during the antibiotic complex formation with respect to the amino group was decreased.
mesh_terms: D000900:Anti-Bacterial Agents / Q000037:antagonists & inhibitors*; D000935:Antifungal Agents / Q000494:pharmacology*; D002174:Candicidin / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D004355:Drug Stability; D004356:Drug Storage; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals; D011090:Polyenes / Q000037:antagonists & inhibitors*; D013696:Temperature
chemical_list: D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D005609:Free Radicals; D011090:Polyenes; D002174:Candicidin
vernacular_title: Izuchenie mekhanizma inaktivatsii polienovykh antibiotikov. Vozmozhnye puti stabilizatsii levorina.