FLUID CO2 EXTRACTION AND HYDRODISTILLATION OF CERTAIN BIOCIDAL ESSENTIAL OILS AND THEIR CONSTITUENTS

Natural products, traditionally used as biocides in indigenous culture s,are being reevaluated for safer means of bacterial and pest control, as compared to the synthetics. While unequivocal identification of bi oactive components of plant extracts is difficult due to synergy and o ther type of interactions among the constituents, a variety of terpeno ids in the essential oils have been shown to be bioactive. The qualita tive and quantitative composition of the extracts vary depending upon the extraction conditions. In this article, studies on four common her bs Murraya koenigii, Lantana camara, Ocimum sanctum and Tagetes patula are presented.These herbs were extracted by liquid CO2 (subcritical l iquid extract; SLE), supercritical fluid CO2 (supercritical fluid extr act; SFE) and hydrodistillation. The components extracted were charact erized by TLC, GC and GC/MS.