Long-Chain Alkylphenol Biodegradation Potential of Soil Ascomycota.

A total of 11 ascomycete strains destructing technical nonylphenol (NP) and 4-tert-octylphenol (4-t-OP) were isolated from NP-contaminated soddy-podzolic loamy soil (Leningrad Region, Russia). The isolates proved capable of degrading NP and 4-t-OP at a high load (300 mg/L). The most efficient Fusarium solani strain 8F degraded alkylphenols (APs) both in cometabolic conditions and in the absence of additional carbon and energy sources. A decrease in APs was due to biodegradation or biotransformation by the strain and, to a minor extent, absorption by fungal cells. NP and 4-t-OP half-lives were, respectively, 3.5 and 6.4 h in cometabolic conditions and 9 and 19.7 h in the absence of additional carbon and energy sources. Amounts of the lipid peroxidation product malondialdehyde (MDA) and reduced glutathione (GSH) increased during NP and 4-t-OP biodegradation in cometabolic conditions by 1.7 and 2 times, respectively, as compared with a control. A high GSH level in F. solani 8F cells potentially implicated the metabolite in both AP biodegradation and strain resistance to oxidative stress. The study is the first to report on the NP and 4-t-OP degradation by the ascomycete F. solani in cometabolic conditions and in the absence of additional carbon and energy sources. The high AP degradation potential of soil ascomycetes was assumed to provide a basis for new environmentally safe bioremediation technologies for purification of soils and natural and waste waters contaminated with endocrine disruptors.

[Destruction of mustard gas hydrolysis products by marine and soil bacteria].

Destruction of mustard gas hydrolysis products by bacterial cultures isolated from soils and bottom waters at the sites of chemical weapons disposal has been studied. Among the tested microorganisms, the soil bacteria Pseudomonas putida Y-21 and Rhodococcus erythropolis 8D and the marine bacteria Achromobacter sp. 75-1, Arthrobacter sp. 23-3, and Pseudomonas sp. 93-2 show the highest activity. Thiodiglycol is utilized by two pathways; one of them, with formation of [(2-hydroxyethyl)thio]acetic and thiodiglycolic and thioglycolic acids, is a common pathway for all bacteria under study. The results demonstrate both the possibility of self-purification of natural objects by natural communities of microorganisms and the prospects for application of microorganisms--destructors in bioremediation of polluted territories.

[Biological abilities and identification of the polyene antifungal antibiotic, perspective for protection from fungi biodeterioration].

The producer of the antifungal polyene antibiotic, aimed to protect against fungial biodeterioration, has been isolated from the soil due to a target search. Based on the morphological, cultural, and biochemical abilities, the producer is related to the Streptomyces genus. It has been shown by chromatographic, spectral, physical, and chemical methods that the antibiotic synthesized by the isolated culture consists of two main components--the polyene hexaene antibiotic with a high antifungal activity and a non-polyene antibiotic with antibacterial activity. The antifungal activity of the low purified hexaene antibiotic is comparable with the antifungal activity of the well-known highly purified antibiotics--amphotericin B, clotrimazole, and itrakonazol. This antibiotic inhibits the synthesis of the biodeterioration factors in fungi, i.e., pigments and organic acids.

[Acitivity of the oxidoreductases of Actinomyces levoris strain No. 28 cultured on a medium with varying redox potential values]. / Aktivnost' nekotorykh okislitel'no-vosstanovitel'nykh fermentov Actinomyces levoris shtamm No. 28 pri kul'tivirovanii na srede s razlichnymi znacheniiami redokspotentsiala.

When the levorin-producing organism Actinomyces levoris, strain 28 was cultivated on fermentation media under conditions of decreased oxidative-reduction values, a significant decrease in the processes of the culture multiplication and antibiotic production was observed. It was shown that the marked decrease in the catalase activity accompanied by a simultaneous increase in the dehydrogenase activity was one of the causes of the decrease in the processes of the culture multiplication and levorin synthesis. Addition of potassium chloride (0.2 per cent) stimulated the catalase activity and promoted the biomass increase and to some extent the antibiotic production.