The aerobic dechlorination activities of two bacterial species isolated from a refuse dumpsite in Nigeria Authors Ademola O. Olaniran Department of Microbiology, Obafemi Awolowo University, Ile-Ife, Nigeria Anthony I. Okoh Department of Microbiology, Obafemi Awolowo University, Ile-Ife, Nigeria Stella Ajisebutu Department of Microbiology, Obafemi Awolowo University, Ile-Ife, Nigeria Peter Golyshin Molecular Microbial Ecology Laboratory, Division of Microbiology, National Research Center for Biotechnology (GBF), Braunschweig, Germany Gbolahan O. Babalola Department of Microbiology, Obafemi Awolowo University, Ile-Ife, Nigeria Keywords: dechlorination, bioremediation, dehalogenation, dumpsite Abstract Two bacterial species isolated using enrichment culture techniquesfrom the topsoil of a main refuse dumpsite in Nigeria were assessed for their dehalogenation potentials. The bacterial isolates were identified asbelo nging to the Bacillus and Pseudomonas genera. Axenic culturesof the isolates utilized monochloroacetic acid (MCA), trichloroacetic acid (TCA), trichloromethane (CHCl3) and tetrachloromethane (CCl4) as the sole source of carbon for growth up to a final substrate concentration of 0.1% (w/v). The mean generation timesof the isolatesin all the growth media ranged significantly (P < 0.05) from 2.41 to 10.04 h and were generally higher than that observed in glucose medium (1.46—1.51 h). The numbers of the chloride atoms in the different organochlorides were negatively correlated with the ability of the organisms to degrade the compounds. Dehalogenase specific activities of the cell-mediated culturesranged from 0.1 to 0.96 μg ml-1 chloride release (mg protein)-1 h-1 and were significantly (P < 0.05) higher than that of the cell-free extract [0.09—0.8 μg ml-1 chloride release (mg protein)-1 h-1]. The optimal pH of the dehalogenase activity was found to be 8.0, and the optimal temperature was between 30 and 35°C. Downloads PDF Published 2010-03-10 Issue Vol. 5 No. 1 (2002) Section Research Articles License Submission of a manuscript to International Microbiology implies: that the work described has not been published before, including publication in the World Wide Web (except in the form of an Abstract or as part of a published lecture, review, or thesis); that it is not under consideration for publication elsewhere; that all the coauthors have agreed to its publication. The corresponding author signs for and accepts responsability for releasing this material and will act on behalf of any and all coauthors regarding the editorial review and publication process.If an article is accepted for publication in International Microbiology, the authors (or other copyright holder) must transfer to the journal the right–not exclusive–to reproduce and distribute the article including reprints, translations, photographic reproductions, microform, electronic form (offline, online) or any other reproductions of similar nature. Nevertheless, all article in International Microbiology will be available on the Internet to any reader at no cost. The journal allows users to freely download, copy, print, distribute, search, and link to the full text of any article, provided the authorship and source of the published article is cited. The copyright owner's consent does not include copying for new works, or resale. In these cases, the specific written permission of International Microbiology must first be obtained.Authors are requested to create a link to the published article on the journal's website. The link must be accompanied by the following text: "The original publication is available on LINK at <http://www.im.microbios.org>. Please use the appropiate URL for the article in LINK. Articles disseminated via LINK are indexed, abstracted, and referenced by many abstracting and information services, bibliographic networks, subscription agencies, library networks, and consortia.