Comparison of total chitinase production in Lecanicillium lecanii. A study between Mexican native and ARSEF strains
Comparação da produção total de quitinase em Lecanicillium lecanii. Um estudo entre estirpes nativas mexicanas e ARSEF
Keywords:chitinase production, Lecanicillium Lecanii, entomopathogenic fungi, mycoparasite, biological control
A comparison of total chitinase activity in 12 Mexican native and 7 ARSEF strains from the entomopathogen and mycoparasite Lecanicillium lecanii was performed. For the determination of the enzymatic activity, a water-based medium was used as substrate and carbon source, supplemented with colloidal chitin stained with Remazol brilliant blue. Chitinolytic activity was determined by measuring the amount of dye released; the supernatant from the cultures was analyzed by spectrophotometry. One chitinase unit was defined as the amount of enzyme needed to elevate absorbance by 0.01 at 595 nm. Native strains EH-458 (2), EH-472, EH-572 (2); as well as reference strains EH-628 and EH-634 showed chitinolytic activity since the moment of inoculation. Higher activities were evident after 288 h in EH-348 (2) and reference EH 628 with 25.1 and 20 ChU/mL, respectively. While strains EH-627 and EH-459 showed their highest activity after 312 h with 15.7 and 36 ChU/mL. The assay allowed the detection of the response to the culture media, as well as the comparison of the total chitinase secreted during the analysis by the 19 strains. We suggest that Mexican native strains EH-348 (2) and EH-459 are highly chitinolytic organisms that could be used as Biocontrol Agents.