Isolation of Dalmatian chamomile extracts - environmentally friendly natural compounds with insecticidal action

Abstract

Abstract Extracts of Dalmatian chamomile (Pyrethrum cinerariaefolium Trev) grown in the greenhouse complex of the Institute of Phytopathology were obtained. The resulting extracts were isolated from the dried inflorescences of this plant, by an initial stepwise extraction of lipid fractions with a mixture of dichloroethane / petroleum ether, methanol and a mixture of methanol / petroleum ether, followed by purification on activated carbon. By further separation of the obtained extracts by preparative column chromatography, biologically active fractions with different contents of natural insecticides from the pyrethrin group were isolated. The content of biologically active components in various fractions was determined by the methods of chromatomass-spectrometry. It was found that low-polarity eluents (hexane / chloroform) recover pyrethrin I, cinerin I, and jasmolin I most fully, and the maximum recovery of pyrethrin II and cinerin II is observed when using relatively polar eluents (hexane / acetone). The insecticidal effect of the end products on the great cereal aphid (Sitobion avenae) was studied. It was found that the maximum insecticidal effect (100% mortality of insects) was exhibited by the pyrethrine fraction isolated during extraction with low-polarity eluents (hexane / chloroform). It was found that the pyrethrine fraction isolated during extraction with relatively polar eluents (hexane / acetone) exhibited a moderate insecticidal effect (77–81% of insect mortality). It has been shown that Dalmatian chamomile extracts have a high insecticidal effect against such a pest of cereal crops as the large cereal aphid and can be successfully used as effective, environmentally friendly natural insecticides, including in the form of biologically active additives to commercial insecticidal preparations.