Ida Bagus Wayan Gunam, I Made Febriana, Anak Agung Made Dewi Anggreni, I Gede Arya Sujana, I M. Mahaputra Wijaya and A. A. S. A. Sukmaningsih

​

PHYSIOLOGICAL CHARACTERIZATION OF Klebsiella variicola R5I4 FOR AMYLASE PRODUCTION UNDER VARIABLE pH AND CULTURE MEDIA

​

Abstract 

​

A novel bacteria Klebsiella variicola R5I4 which capable of converting starch into sugar was previously found suggesting it is an amylase producing bacteria; however its characteristics is not yet clearly elucidated. One of which is optimal media requirement. Optimal media is required for the growth of microorganisms such as bacteria, yeasts, and molds. Some types of microbes can live well on very simple media, which only contain inorganic salts plus organic carbon sources such as sugar. However, microbes that require complex medium that not only contains carbon and nitrogen sources but also needs the addition of other complex ingredients also exist. This research was aimed to characterize the physiology of Klebsiella variicola R5I4 for amylase production at various pH levels and culture media. The types of media which are tested in this work are: nutrient broth, starch broth, and yeast extract-peptone-glucose, meanwhile the pH value tested are pH 6, 7, and 8. The optimal media found in this study is starch broth media at pH 6 which was able to produce an OD660 value of 1.925 ± 0.11 and corresponding to total microbial count of 8.76 x 106 CFU/mL, and produced amylase enzyme activity of 2.720 ± 0.036 IU/mL with total reduction sugar produced of 4.896 ± 0.065 mg/mL and final total soluble solids of 6.5 ± 0.14 °Brix.

​

Full text​​

​​​