Amylase enzyme is one of the potential enzymes in industrial processes. Some food and beverage industries require amylase enzymes which are resistant to high temperature and acidity to hydrolyze starch. Amylase enzymes with such characteristics can be obtained from bacteria inhabited hot and acidic regions. Bacterial amylase production is economical because the enzyme production rate is higher in bacteria compared to other microorganisms. South Kalimantan has potential wetland areas such as swamps, peatlands, and hot springs that require to explore for its microbes, especially thermophilic and acidophilic amylolytic bacteria. The research aimed to isolate thermophilic and acidophilic amylolytic bacteria from South Kalimantan wetlands, and to measure their amylase activity. The isolation was done by serial dilution and plating method in specific media. Total of seven bacterial colonies was isolated from the soil samples of South Kalimantan peatlands and swamps. All isolates were tested for amylolytic activity, and the enzyme activity unit was calculated. Five out of seven bacterial isolates demonstrated amylolytic activities. They were three isolates of thermostable and acidophilic amylolytic potential bacteria (M2S2, M1S2, and G2S4) and one isolate capable of producing thermostable amylase enzyme (M2S1). The highest amylolytic index was in M1S2 isolates reaching 2.37. Coarse amylase derived from M1S2 isolates showed the highest activity of 0.178 unit/ml with a glucose concentration of 413.44 µg/ml. The isolates are being identified molecularly using 16S-rRNA gene.

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