Table of Contents
International Scholarly Research Notices
Volume 2014, Article ID 762070, 8 pages
http://dx.doi.org/10.1155/2014/762070
Research Article

Treatment of Palm Oil Mill Effluent by a Microbial Consortium Developed from Compost Soils

1Department of Microbiology, University of Nigeria, Nsukka 410001, Nigeria
2Department of Bioscience and Bioengineering, Graduate School of Life and Environmental Sciences, University of Tsukuba, Tennodai 1-1-1, Tsukuba-shi, Ibaraki 305-8572, Japan

Received 21 August 2014; Accepted 7 October 2014; Published 29 October 2014

Academic Editor: David Rodríguez-Lázaro

Copyright © 2014 Charles O. Nwuche et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

A method for the aerobic treatment of palm oil mill effluent (POME) was investigated in shake-flask experiments using a consortium developed from POME compost. POME was initially centrifuged at 4,000 g for 15 min and the supernatant was enriched with (NH4)2SO4 (0.5%) and yeast extract (0.25%) to boost its nitrogen content. At optimum pH (pH 4) and temperature (40°C) conditions, the chemical oxygen demand (COD) of the effluent decreased from 10,350 to 1,000 mg/L (90.3%) after 7 days. The total bacterial population determined by plate count enumeration was 2.4 × 106 CFU/mL, while the fungal count was 1.8 × 103 colonies/mL. Bacteria of the genera Pseudomonas, Flavobacterium, Micrococcus, and Bacillus were isolated, while the fungal genera included Aspergillus, Penicillium, Trichoderma, and Mucor. When the isolated species were each inoculated into separate batches of the raw effluent, both pH and COD were unchanged. However, at 75 and 50% POME dilutions, the COD dropped by 52 and 44%, respectively, while the pH increased from 4 to 7.53. POME treatment by aerobic method is sustainable and holds promising prospects for cushioning the environment from the problems associated with the use of anaerobic systems.