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Streptomyces sp. strain SB9 was isolated from perm frost soil samples in Spitsbergen, Arctic Ocean; it grows in a temperature range between 4 degrees C and 28 degrees C. During the survey of biologically active metabolites biosynthesized by this strain, significant amounts of alpha,alpha-trehalose (1) and glycerol (2) were detected. The compounds were isolated from the mycelium, were chromatographically separated, and the structures were elucidated on the basis of MS and NMR measurements. A possible role of trehalose in cold adaptation of the strain was examined. It was determined that the mycelium of the strain cultivated at 4 degrees C accumulated 5-fold higher amounts of trehalose in comparison with the cells cultivated at 28 degrees C. The mesofilic reference strains, Streptomyces spectabilis NRRL 2494 and Streptomyces lividans TK64, accumulated 100-fold less trahalose than the psychrotolerant Streptomyces sp. SB9. High amounts of trehalose in the cells could be a reason for adaptation of the strain to life at Arctic conditions.

A new sulphur-containing natural alkaloid named microbiaeratin (1a) was isolated, together with the known microbiaeratinin (2, bacillamide) from the culture filtrate of Microbispora aerata strain IMBAS-11A. The organism was isolated from penguin excrements collected on the Antarctic Livingston Island. The structure was elucidated by one- and two-dimensional NMR experiments and mass spectrometric investigations.

The fungus, Tritirachium sp. HKI 0317, was isolated from the Antarctic lichen Neuropogon sp. Fermentation of this strain, extraction of the culture broth, and preparative separation of produced compounds furnished 4-carboxy-5,5'-dihydroxy-3,3'-dimethyldiphenylether (1), macrosphelide A (2), and macrosphelide J (3). The structures were elucidated on the basis of MS and NMR measurements, and the previously published data for this compounds.

Sanionins A (1) and B (2) were isolated from the moss Sanionia georgico-uncinata, collected on the Antarctic Livingston Island. The compounds 1 and 2 were purified by solvent extraction, silica gel column chromatography, and preparative HPLC, consecutively. The structures of the both compounds were elucidated by 1D and 2D NMR experiments and mass spectrometric investigations. These compounds showed activity against important Gram-positive pathogens, such as mycobacteria, multiresistant staphylococci, and vancomycin resistant enterococci. This activity is combined with antiinflammatoric activity and low cytotoxicity.