Philippine E-Journals

Screening and Identification of Alkaliphilic Bacteria Producing Cyclodextrin Glucanotransferase and Proteases from Manleluag Hyperalkaline Spring

Eula Francia M. Bosito | Aprill P. Manalang | Noel G. Sabino | Rose Ann G. Franco | Ma. Genaleen Q. Diaz | Andrew D. Montecillo | Nacita B. Nacita

 

Abstract:

Manleluag hyperalkaline spring is a unique spring in Pangasinan, Philippines. In this study, alkaliphilic bacteria were screened for the presence of industrially important enzymes – cyclodextrin glucanotransferase (CGTase) and proteases. From a total of 826 bacterial isolates, 54 isolates exhibited significant CGTase production evaluated using the Phenolphthalein Assay. The highest recorded CGTase activity is at 46.01 U/ml. Using two pH conditions (pH 7 and pH 10), 428 isolates showed protease activity when tested using Skim Milk Assay with an activity reaching up to a clearing zone ratio of 0.2056. Based on whole-genome sequence assemblies, the top CGTase producer was found to be a Bacillus lehensis isolate while the top protease producer was a putative Bacillus gibsonii isolate. Hence, this study showed that the Manleluag hyperalkaline spring served as a good source of alkaliphilic bacteria producing industrially important compounds.