Neutral lipids of the fungus Zoophthora (Erynia) ovispora (NOWAKOWSKI) BATKO

Abstract

The main components of the neutral lipid fractions, isolated from Zoophthora (Erjmia) ovispora, were determined. Triglycerides constitute 56% of total lipids. among them dilaurinostearate glyceride constitutes 43.3%. The major fatty acid -lauric acid (32.3%) is related mainly to tri-and diglycerides. The level of stearic acid is slightly lower (29.8%) but distinctly predominates in free acid fraction. Diglycerides and steroids were present in smaller amounts -1.2% and 4.8%, respectively. Cholesterol exceeds considerably ergosterol.Small differences in morphology and specificity of fungi belonging to the Zoophthera genus cause many problems in their taxonomy (BALAZY 1986). In previous publication we described our attempts to utilize an enzymatic activity of selected fungi of the Z. Zoophthora, Z. Erjwia and Z. Neoparidora subgenus as criteria in their taxonomy. However, observed lipolytic, chitinolytic, proteolytic and amylolytic activities were not enough specific to be crucial argument in their classification (URBANCZYK et al. 1992). Therefore, we decided to perform analysis of the neutral lipid fraction isolated from one fungus species of Zoophthora genus and to compare it with lipids isolated from other fungi of the Entomophthoraceae family. The compositions of fatty acids were often utilized in the chemotaxonomy of microorganisms by many authors (TYRREL 1967, LATGE and DE BIEVRE 1980, MUMMA and In this paper we describe the components of the neutral lipid fractions isolated from the Zoophthora (Erynia) ouisporu (NOWAKOWSKI) BATKO. This microorganism has been deposited (under no 1854) in the mycological collection of the Research Institute of Agricultural and Forest Environment of the Polish Academy of Sciences in Poznan. The Z. (Erynia) ovispora (NOWAKOWSKI) BATKO shows the ability to infect nomatocerous, brachycerous and calyptrate flies (hitherto found on insects belonging to families : Culicidae, Linioniidae, Psychodidae, Tendipedidue, Tipulidae, Syrphidae, Sarcophagidue and Calliphoridae). Therefore, this fungus should be considered as a widely oligophagous species. Because its laboratory cultivation is not too difficult (URBANCZYK et a/. 1992). This microorganism could be considered as a potential biolgical insecticide.Contribution of particular components in the lipid fraction depends on time of microorganism cultivation. In separate experiments we found that the greater increase of mycelium mass was observed between 6 and 7 day (Fig. 1). On the other hand, the greatest amounts of the neutral lipid fractions were extracted from the cultures of 10 days old. We have also found that at this time the composition of lipids was also the most diversified (Fig. 2). Therefore, we decided to take to our studies the lipid fractions produced by this microorganism in 10th day of culturing.