Optimisation of composition of media for the production of amylolytic enzymes by Thermomyces lanuginosus ATCC 34626

The composition of media for the production of amylolytic enzymes by Thermomyces lanuginosus was optimised in different ways. Effects of various carbon and nitrogen sources were investigated. Thermomyces lanuginosus grown on starch, maltodextrin, dextrin, maltose, amylopectin, glucose and dextran substrates showed good alpha-amylase (92-125 U/mL) and glucoamylase (6-13 U/mL) activities. Among the tested nitrogen sources L-asparagine was the best one. The optimum pH of fermentation medium was found and fixed to 4.9 by using 100 mM citrate buffer for the production of amylolytic enzymes. Response Surface Method (RSM) was applied for searching the optimum concentration of components of media for amylolytic enzyme production. A second-order polynomial model was fitted at significance level 95 % (P<0.05) for both a-amylase and glucoamylase. The developed composition of media was checked in respect of the production of amylolytic enzymes. The concentration of L-asparagine was adjusted to 0.75 %. The concentration of starch was set at 6.5 % for alpha-amylase and 2 % for glucoamylase.