By-product hydrosol of Eucalyptus globulus essential oil distillation as source of botanical insecticides: wealth from waste

Abstract

Worldwide use of chemical pesticides is on rise which is creating a big problem to environment and human health. Hence great interest has been generated to find out botanical leads having anti-pest properties from medicinal plants. The objective of this work was to evaluate the insecticidal potential of Eucalyptus globulus waste hydrosol obtained after essential oil distillation. Samples of Eucalyptus globulus genus were collected from near-by areas of study, and were hydro-distilled and their by-product ‘hydrosol was analyzed for phenolics and tannin determination. UV-VIS, FT-IR and fluorescent study was also conducted of by-product hydrosol. In addition, insecticidal activity of by-product hydrosol was also monitored against mealy bug. Substantial amount of phenolics and tannins were detected in the by-product hydrosol. UV and fluorescent spectroscopy revealed the presence of secondary metabolites. Significantly higher insecticidal activity was observed of by-product hydrosol against mealy bug. The results suggested that by-product hydrosol from Eucalyptus globulus essential oil distillation can be considered as potential candidates for bio-control of pests.

Keywords

• botanicals; insecticide; plant allelochemicals; plant protection; toxicity