The repression of alkaline protease synthesis from alkaliphilic actinomycete was studied by using glucose, peptone, yeast extract, KH2PO4 and amino acids; tyrosine, tryptophan, lysine, and arginine. There was a critical limit of stimulation of enzyme production by these components. Crude components such as molasses, wheat flour, and wheat bran were found to be effective for growth and enzyme production. The high level of enzyme production using agro-industrial by-products is commercially significant due to cheap nature of these sources. The findings are quite attractive, as only few actinomycetes, particularly alkaliphilic ones, have so far been explored for their enzymatic potential and regulation of enzyme synthesis. (c) 2005 Elsevier Ltd. All rights reserved.