Secondary metabolites of the genus Penicillium from undisturbed and anthropogenically altered Antarctic habitats.

From undisturbed Antarctic habitats (permafrost sediments 30-150 thousand years of age, water of Radok Lake) and superficial deposits contaminated with petroleum products, we isolated 14 and 9 strains of Penicillium fungi, respectively. Comparison of the fungal complexes showed them to differ by species composition; only two species-P. palitans and P. solitum-were in the species lists of both groups. The identified secondary metabolites in the investigated strains belonged to diketopiperazine (group of roquefortines, rugulosuvin B), benzodiazepine (anacin, cyclopenins), quinoline alkaloids (viridicatins), clavine ergot alkaloids (α-cyclopiazonic acid, festuclavine, fumigaclavines), polycyclic indole alkaloids (communesin B, chaetoglobosin A), amino acid derivatives (N-acetyltryptamine, chrysogins, penicillin G), polyketides (citreoviridin A, mycophenolic acid), and terpenes (andrastins, phomenone). Strains isolated from anthropogenically altered habitats produced a more complete and characteristic profile of exometabolites, as compared with strains isolated from undisturbed habitats. It is only from contaminated soils there were isolated fungi that produced more structurally diverse secondary metabolites pertaining to polycyclic indole alkaloids and terpenoids. The fungi isolated from contaminated samples can be used in biodegradation of oil spills and bioremediation of the environment, and also as producers of promising biologically active compounds.

Exo-metabolites of mycelial fungi isolated in production premises of cheese-making and meat-processing plants.

Data were obtained on the species composition of mycelial fungi isolated from the air of workrooms and production premises in cheese-making and meat-processing plants. The strains studied were shown to be capable of producing various low molecular weight compounds. Many of them are mycotoxins such as α-cyclopiazonic acid (CPA), mycophenolic acid (MPA), citrinin, cladosporin, roquefortine and ergot alkaloids. The profiles of the secondary metabolites were used to elucidate the species' names of the isolated strains.

New diketopiperazine alkaloids from Penicillium fellutanum.

Four new diketopiperazine alkaloids (1-4) were isolated from cultures of Penicillium fellutanum, and their structures were determined by MS and NMR measurements.

Study of the alkaloid composition of the food-infecting penicilles.

Over 30 strains of various Penicillium sp. isolated from food have been screened for the ability to synthesize mycotoxins of an alkaloid nature. The most productive were P. expansum, P. raciborskii, P. puberulum, P. commune, P. viridicatum, P. chrysogenum, P. palitans, P. purpurescens and P. cyclopium. The separate components of the alkaloid mixtures have been isolated and identified. The range of metabolites synthesized by different strains of the same species was considerably expanded. New producers of aurantioclavine, meleagrin, roquefortine, rugulovasine, clavine alkaloids and some other compounds have been found. It was shown that the alkaloid composition and content were dependent on the medium, culture age and method of cultivation.

Synthesis and metabolism of roquefortine in Penicillium species.

The uptake of exogeneous 14C-roquefortine by Penicillium farinosum cells and its metabolism was followed. Growth and roquefortine biosynthesis of three Penicillium species during a cultivation period of 14 d were investigated. Furthermore, the effect of cultivation conditions viz. various culture media on roquefortine uptake and biosynthesis as well as biomass production were studied. Some general problems of physiology and metabolic regulation of alkaloid formation in Penicillium species were discussed.