BACILLUS THURINGIENSIS مقايسه چند روش مختلف براي رديابي و تعيين ميزان بتااگزو توكسين در فرآورده هاي باكتري

Comparison of several methods for detection and quantification of 0- exotoxin in commercial Bacillus thuringiensis products

The B- exotoxin (also called thuingiensin and therm() stable toxin) is toxic to human and other animals. Because of vertebrate toxicity, most commercial preparation of B. thuringiensis is composed of subspecies or isolates that do not produce B- exotoxin. As a condition for registration for pesticide use on food in USA, B. thuringiensis active ingredients must be tested to show the absccnse of B- exotoxin. In this study screening methods for the presence of B- exotoxin in a product of B. thuringiensis subsp. aizawai (BtH) were based on laboratory bioassay against lepidopteran larvae and High Perfonnance Liquid Chromatography (HPLC). The bioassay and HPLC assay results indicated that the B- exotoxin was presence in the product of B. thuringiensis subsp. aizawai (BtH). Bioassay was showed to be more sensitive than High Performance Liquid Chromatography (HPLC). Bioassay can he used to detect and qualify B. thuringiensis 13- exotoxin and can be a useful tool for quality control.