Promising Bioactive Streptomyces Sp. Strains E2S7, A6B9 And C2K4 For Amylase Production Isolated From Arid And Semi-Arid Zones Of Algeria

This study aimed to isolate and characterize actinobacteria capable of producing amylase enzymes from soils in arid and semi-arid zones of Algeria, including the Oasis de Djanet, Tassili de Djanet, and Forêt d’Elouricia. From 42 isolates screened on starch agar, three strains—E2S7, A6B9, and C2K4—demonstrated strong amylolytic activity and were identified by 16S rRNA sequencing as Streptomyces hypolithicus, S. indoligenes, and S. candidus, respectively. Amylase production was induced with 1% starch at 37°C. The highest enzymatic activities were recorded at 8.36, 8.90, and 9.32 U/mL under optimal conditions of 30°C and pH 7.0. The enzyme activity showed a pH optimum of 8.0 and a temperature optimum of 45°C. These strains exhibit significant potential for industrial applications, particularly in biotechnology and agriculture.