ABSTRACT
Using herbs as an insecticide or pesticide is well known in traditional agriculture. They are biodegradable and also friendly to environment. However, developing of commercial product from herbal plants was limited due to degradation of active ingredients, the variation of active content and there is no standard procedure for quality control. In this research, crude extracts of tobacco leaves (Nicotiana tabacum Linn., Solanaceae) containing nicotine as an active ingredient were studied for developing as concentrated emulsion preparation. Crude tobacco extracts from 95% ethanol were obtained as a brown syrupy mass with strong odors and 19.55% yield. One of the active ingredients, nicotine was selected to be used as a marker in suitable high performance liquid chromatography (HPLC) system in this study. The tobacco extract was stable under acid, base and heat conditions. Therefore, it was selected for further development as a concentrated emulsion formulation. The concentrated emulsion of tobacco extract composed of 10% w/w nicotine was prepared by combining fixed oil (palm oil), emulsifiers (Tween and Span), giving a more physically stable product. Under room temperature and 70 % RH for 6 month, the overall of % amount of nicotine in the product still remained in acceptable level. In the next step, the product was studied in the field with various dilution ratios of water to find out a suitable concentration of product using in agriculture field. It showed that all of the exhausted died and the plants trials are still green and not burned when the dilution is 100 time of its product.