TITLE:
Investigation on the insecticidal limonoid content of commercial biopesticides and neem extract using solid phase extraction
AUTHORS:
Ji-Won Lee, Cho-Long Jin, Ki Chang Jang, Geun-Hyoung Choi, Hee-Dong Lee, Jin Hyo Kim
KEYWORDS:
Solid Phase Extraction; Azadirachitn; Salannin; Quantitative Analysis; Biopesticide
JOURNAL NAME:
Journal of Agricultural Chemistry and Environment,
Vol.2 No.4,
November
5,
2013
ABSTRACT: Neem extract is an alternative insecticide for organic farming and is an allowed component for commercial biopesticide in Korea. However, crop protection properties are not consistent in commercial products. In this report, quantitative analysis of commercial biopesticides for the four insecticidal limonoids of neem extract-azadirachtin A, azadirachtin B, deacetylsalannin and salannin, was conducted through solid phase extraction method with lipophilic-hydrophilic balanced material. The recoveries of the four limonoids ranged from 80.5% to 105%, and their limit of quantitation ranged from 0.028 mg/L to 0.356 mg/L. On the five imported neem extracts, the total contents of the four bioactive limonoids extracted were from 321 mg/L to 5810 mg/L, but there were big variations in the relative composition of the limonoids. The total limonoidal concentrations in 23 commercial bio-pesticides made from neem showed from below LOQ to 7190 mg/L with significant differences in the relative composition. These differences determine the biopesticide’s efficacy on pests, therefore, tracking the active ingredients is necessary for the quality control of commercial bio-pesticides.