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Studies in man and laboratory animals suggest that omega 3 polyunsaturated fatty acid constituents of fish oils have antiatherosclerotic properties. We have studied the effects of several such polyunsaturated fatty acids for ability to modify the in vitro release of mitogens from human platelets. Such mitogens may produce the fibro-proliferative component of atherosclerotic plaques. Both 5,8,11,14,17-eicosapentaenoic acid (20:5 omega 3) and 4,7,10,13,16,19-docosahexaenoic acid (22:6 omega 3), major constituents of fish oils, inhibited adenosine diphosphate-induced aggregation of platelets and the accompanying release of mitogens. These effects are dose dependent. Linolenic acid (18:3 omega 3), the biosynthetic precursor of eicosapentaenoic acid, also inhibited platelet aggregation and mitogen release. Eicosapentaenoic acid also inhibited mitogen release from human monocyte-derived macrophages, which, in vivo, are an additional source of mitogens during atherogenesis. Potent inhibition of human platelet aggregation and mitogen release was also seen with dihomo-gamma-linolenic acid (8,11,14-eicosatrienoic acid 20:3 omega 6), whose levels are reportedly elevated in Eskimos subsisting on marine diets. We conclude that diets that elevate plasma and/or tissue levels of eicosapentaenoic acid, docosahexaenoic acid and dihomo-gamma-linolenic acid precursor gamma-linolenic acid (18:3 omega 6) may exert antiatherosclerotic effects by inhibiting the release of mitogens from platelets and other cells.

Biocontrol offers an attractive alternative to the use of chemical pesticides in agricultural pest management. The development of high levels of resistance to chemical pesticides have forced researchers to find more alternative biological control agents. The aims of this study were to isolate Paecilomyces spp. with high virulence against diamondback moth (Plutella xylostella) and Oriental leafworm moth (Spodoptera litura), and to investigate suitable agro-industrial residues as a substrate used for solid state fermentation for sporulation of isolates. In this study, Paecilomyces spp. were isolated from soil and insects and identified by morphological and sequencing analyses. The pathogenicity of these isolates was evaluated on Pl. xylostella and S. litura to identify strains with the highest virulence. In addition, agro-industrial residues were used as a cheap substrate for investigating a suitable medium for sporulation on an industrial scale. Six strains of Paecilomyces spp. were isolated including one strain of P. lilacinus and five strain of P. javanicus. P. lilacinus PL01 showed the highest virulence against both Pl. xylostella and S. litura with respective LT 50 values of 2.51 and 7.09 days. The five isolated P. javanicus strains also strongly infected Pl. xylostella with LT 50 values of 2.52~6.59 days. For sporulation, brown rice alone or brown rice mixed with rice husks and wheat bran or rice bran was suitable for cultivating these isolates. Two newly isolated species of Paecilomyces, P. lilacinus and P. javanicus, can be used as biological control agents for controlling Pl. xylostella and S. litura.