eng Oriental Scientific Publishing Company Biosciences Biotechnology Research Asia 0973-1245 2016-05-06 8 2 693 699 9508 article K.Sreenivasa Rao 1 P. Ellaiah 2 Karnakumar 1 RRKS,s College of Pharmacy, Bidar, Karnataka (India). College of Pharmaceutical Sciences, Andhra University, Visakhapatnam, Andhra Pradesh (India). The strains of Thermoactinomyces thalpophilus KS-05 was subjected to strain improvement program with a view to obtain increased amylase production. The most effective mutagens, Ultra Violet rays (UV) and Ethyl Methyl Sulphonate (EMS), were chosen for strain improvement. The results indicated that among UV mutants, KSR 14, KSR 17 & KSR 22 showed enzyme yields of 1924, 1986 and 1998 U/ml respectively .All these three mutants were further subjected to EMS treatment and a total of 21 mutants were selected and tested for their amylase producing capacities. The results indicated that the mutant KSV 17 derived from the parent culture KS-05 was the highest amylase yielding strain (2476.6 U/ml). The UV mutation resulted in a mutant KSR 22 with 1998 U/ml productivity which is 13.5% higher production than parent strain. The chemical mutagen (EMS) yielded a better amylase producing mutant KSV 17 with 2476.6 U/ml. Thus the strain improvement programme resulted in a mutant that produced 2.19 times higher titres of amylase over the parent wild strain (1128 U/ml), which is a significant increase of yield. https://www.biotech-asia.org/vol8no2/strain-improvement-studies-on-t-thalpophilus-strain-ks-05/ Thermoactinomyces thalpophilus; Ethyl Methyl Sulphonate (EMS); Ultra violet irradiation (UV)