Characterization and optimization of abamectin-a powerful antiparasitic from a local Streptomyces avermitilis isolate

Abamectin (ABA) constitutes a big commodity for pharmaceutical companies because it generates about one billion dollar annual sale. Avermectins (AVMs) and their naturally occurring analogues, milbemycins (MILs), meilingmycins (MEIs), ivermectin (IVE), abamectin (ABA), and nemadectin (NEM), represent one of the most developed antiparasitic agents. Abamectin is a mixture of avermectin B1a and avermectin B1b. The production of abamectin by Streptomyces avermitilis is a complicated process and separation of two fractions is quite difficult; commercial product contains more than 80% of Bla and less than 20% of B1b components. The main goal of the study was the identification and optimization of fermentation conditions to raise the production of abamectin from Egyptian S. avermitilis. The qualitative and quantitative analysis of avermectins was carried out by thin layer chromatography (TLC) and 6538 Q-TOF with Agilent 1290 UHPLC. The process of identification was carried out by using production medium containing 30 g/L corn starch, and 0.725 g/L CaCO₃, pH 7, 8% inoculum size and incubated at 32.5 °C. The enhancement of the production of abamectin is a big challenge with commercial and industrial importance, as its output is insufficient for human consumption.