Screening and primary identification of lipid degradation microorganism from local bioextracts

Abstract

Bioextract is a solution of fermented organic matters which mainly are agricultural leftover containing living microorganisms. Studies have shown that bioextract may be applied to agriculture, livestock, gardening and landscaping, composting, and bioremediation. Latterly, bioextract was introduced for wastewater treatment, due to bioextract characteristic and environmentally friendly. From previous studies (Nitsuwat et al., 2013), addition of bioextract was capable to reduce total solid, grease and oil in domestic wastewater. The grease and oil component in wastewater can create problem in sewage system and hard to lose from the wastewater. The aim of this research is to find and identify microorganism contained inside the bioextract that can degrade grease and oil. In the future increasing of these microorganisms in bioextract may improve the ability of bioextract for pretreating domestic wastewater containing grease and oil.

In this research, lipid degradation microorganisms were isolated from the local bioextract sample. The bioextract biodivesity was found contained total aerobic bacteria 1.07x104 CFU.ml-1, actinomycetes 4.53x104 CFU.ml-1, yeast 2.67x104 CFU.ml-1, lactic acid bacteria 3.04 x 103 CFU.ml-1, and mold 1.98x103 CFU.ml-1. The screening methods used media added with tributyrin. Colonies that created clear zone were isolated and tested using tributyrin and vegetable oil. Total of 55 microorganisms were screened for their ability to degrade tributyrin. Ten strains were further selected from the second screening using vegetable oil. Then these ten isolates were primarily identified using morphological and biochemical characteristics. Majority of the selected isolates were in family Bacillaceae.