Article info.

ABSTRACT

Received 26 Aug 2016
Revised 17 Nov 2016

Accepted 31 Oct 2017

High lipid (fats and oils) concentration contained in wastewater from restaurants and canteens released into environment directly, leads to polluted water and lock drainpipe systems. The lipid-degradation capability of lipid-degrading yeast was investigated for possible application in treatment of lipids-contaminated wastewater. Twenty-eight yeast isolates were isolated from 11 lipid-contaminated wastewater samples from many restaurants and canteens in Ninh Kieu district of Can Tho city, Vietnam. Fifteen isolates produced halo zones on Tween 20 agar medium and were determined to have ability of lipid-degradation, whereas three of them (B1, ST, Da2a isolates) were found to have the high ability of lipid-degradation by measuring development of halo zone diameter during 72 hours and identified by ITS-PCR (Internal transcribed spacer- Polymerase chain reaction) technique and DNA sequencing. After 7 days of cultivation, the rates of the degradation of lipid contaminated in wastewater by strain B1, ST, Da2a were 74.14%, 83.03% and 80.7%, respectively. The results of DNA sequencing were compared with GenBank database of NCBI by BLAST N software. The sequences from selected isolates showed high degrees of similarity to those of the GenBank references (between 97% and 99%). Isolates of B1 and ST were 99% of similarity with Candida palmioleophila and Meyerozyma quilliermondii, respectively. Da2a isolate was 97% of similarity with Candida tropicalis.

Keywords

Candida, canteens and restaurants, lipid-contaminated wastewater, lipid-degradation yeast, lipid degradation, vegetable oil

Cited as: Tan, N.N. and Diep, C.N., 2017. Isolation and identification of lipid-degrading yeast from wastewater of canteens and restaurants in Ninh Kieu district, Can Tho city. Can Tho University Journal of Science. 7: 27-32.