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Conjugated linoleic acids (CLA) are a mixture of positional and geometric isomers of linoleic acid (cis-9, cis-12 octadecadienoic acid) with conjugated double bounds. Their principal dietary sources include ruminant and dairy fats, and CLA are shown to possess health beneficial effects on human health. Dairy cultures may biologically convert linoleic acid to CLA, but their capability is affected by several factors such as the source and amount of linoleic acid in medium and fermentation conditions. The objective of this study is to determine the ability of lactic cultures isolated from different cheeses to produce CLA from sunflower oil as a natural source of linoleic acid. Results indicated that three strains of Lactobacillus and two strains of Enterococcus were able to increase CLA concentration more than 30% based on the weight of sunflower oil added to model medium. It is recommended that the bioconversion capability of linoleic acid into CLA by these strains should be determined in actual dairy products.

Malassezia species which are lipophilic exobasidiomycetes fungi, have been accepted as members of normal cutaneous flora as well as causative agent of certain skin diseases. In routine microbiology laboratory, species identification based on phenotypic characters may not yield identical results with taxonomic studies. Lipophilic and lipid-dependent Malassezia yeasts require lipid-enriched complex media. For this reason, Fourier transform infrared (FT-IR) spectroscopy analysis focused on lipid window may be useful for identification of Malassezia species. In this study, 10 different standard Malassezia species (M.dermatis CBS 9145, M.furfur CBS 7019, M.japonica CBS 9432, M.globosa CBS 7966, M.nana CBS 9561, M.obtusa CBS 7876, M.pachydermatis CBS 1879, M.slooffiae CBS 7956, M.sympodialis CBS 7222 and M.yamatoensis CBS 9725) which are human pathogens, have been analyzed by FT-IR spectroscopy following standard cultivation onto modified Dixon agar medium. Results showed that two main groups (M1; M.globosa, M.obtusa, M.sympodialis, M.dermatis, M.pachydermatis vs, M2; M.furfur, M.japonica, M.nana, M.slooffiae, M.yamatoensis) were discriminated by whole spectra analysis. M.obtusa in M1 by 1686-1606 cm-1 wavenumber ranges and M.japonicum in M2 by 2993-2812 cm-1 wavenumber ranges were identified with low level discrimination power. Discriminatory areas for species differentiation of M1 members as M.sympodialis, M.globosa and M.pachydermatis and M2 members as M.furfur and M.yamatoensis could not be identified. Several spectral windows analysis results revealed that FT-IR spectroscopy was not sufficient for species identification of culture grown Malassezia species.