An improved bioassay for the detection of Bacillus thuringiensis beta-exotoxin.

Some Bacillus thuringiensis strains secrete beta-exotoxin, which is an insecticidal, thermostable adenine nucleotide analogue. Discrepancies between detection of beta-exotoxin by high-performance liquid chromatography and insect bioassays have shown the importance of bioassays in the determination of beta-exotoxin production. With the aim of improving the fly beta-exotoxin bioassay, a range of fly diets were evaluated and the best performing diet was incorporated into a novel beta-exotoxin bioassay.