Plastic waste disposal is a huge ecotechnological problem and one of the approaches to solving this problem is the development of biodegradable plastics. This review summarizes data on their use, biodegradability, commercial reliability and production from renewable resources. Some commercially successful biodegradable plastics are based on chemical synthesis (i.e. polyglycolic acid, polylactic acid, polycaprolactone, and polyvinyl alcohol). Others are products of microbial fermentations (i.e. polyesters and neutral polysaccharides) or are prepared from chemically modified natural products (e.g., starch, cellulose, chitin or soy protein).

Two ergopeptine alkaloids, alpha-ergocryptine (1) and its C(8) epimer alpha-ergocryptinine, have been isolated from the mycelium and fermentation broth of submerged cultures of Claviceps zizaniae CCM 8240. The structure of 1 was determined by HPLC/positive ion APCI MS and NMR analysis. Alkaloid concentrations of 10 microg/mL in 14-day-old fermentation broth and 1 mg/g of dry mycelium mass were found. These results are of considerable biotechnological interest since these were the only detectable alkaloids produced. Toxicity of naturally occurring sclerotia of C. zizaniae cannot be excluded.

Among 18 tested strains of Claviceps spp., 7 produced significant amounts of exocellular polysaccharide (EPS). The maximum production of EPS was found in fermentation broth of Claviceps viridis. The kinetics of growth, substrate consumption, and EPS production in the batch, aerobic, submerged culture of this fungus were investigated in detail. The experimental data were processed by a simple mathematical model describing mass balance of growth, substrate consumption, formation of intermediates, and production of EPS. The parameters of the model were estimated from data obtained in cultivation performed in flasks and two laboratory fermentors of different size. Physiological similarity was obtained during process scale-up in volumetric ratio 1:100. The sugar consumption efficiency (52%) and observed EPS productivity (1.9 kg/m3 per d) were comparable with literature data.