Fractionation and partial characterization of neem (Azadirachta indica A. Juss) leaf extracts with insecticidal activity

Date

3-1998

Degree

Bachelor of Science in Agricultural Chemistry

College

College of Arts and Sciences (CAS)

Adviser/Committee Chair

Amelia W. Tejada

Abstract

ABSTRACT

MOJICA, ELMER RICO E. University of the Philippines, Los Banos, March 1998. Fractionation and Partial Characterization of Neem (Azadirachta indica A. Juss) Leaf Extracts With Insecticidal Activity

Thesis Adviser: DR. AMELIA W. TEJADA

Neem leaves were serially extracted in a Soxhlet apparatus using the following solvents: petroleum ether, chloroform and methanol. Petroleum ether and methanol extracts showed high mortality when bioassayed against household pests (houseflies and mosquitoes). These extracts were further fractionated using different solvents to obtain the active fraction. IR, UV, GC analyses and solubility tests were done on active fractions to partially identify the components responsible for insecticidal activity. Among the partially purified fractions, the benzene fraction and toluene fraction from petroleum ether extract, showed strong insecticidal activity. IR spectra showed that both fractions contain similar compounds as indicated in the peaks present except for a peak at 2361, which is present in the benzene fraction but absent in the toluene fraction. UV spectra, on the other hand, showed a peak which is present in both toluene and benzene fraction. Other peaks present were not similar for the two fractions. However, GC analysis showed that the benzene fraction is made up of at least four components while the toluene fraction had at least nine components. Both fractions were readily soluble in non-polar solvents. Various formulations of neem mosquito repellant were done at different concentrations. The effectivity of the product increases with increasing concentration. At 1.5% formulation, the results obtained was comparable to that of commercial mosquito coils.

Language

English

Location

UPLB Main Library Special Collections Section (USCS)

Call Number

Thesis

Document Type

Thesis

This document is currently not available here.

Share

COinS