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Journal : Microbiology Indonesia

Optimum Concentration of Glucose and Orange II for Growth and Decolorization of Orange II by Enterococcus faecalis ID6017 under Static Culture

Microbiology Indonesia Vol 2, No 2 (2008): August 2008
Publisher : Indonesian Society for microbiology

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Abstract

Growth and decolorization performance of bacterial grown on azodyes-containing-medium is influenced by various concentrations of carbon sources and azodyes. The optimum level of glucose and Orange II concentration for growth and Orange II decolorization by Enterococcus faecalis ID6017 are reported in this paper. The experiments were carried out in liquid static culture as batch experiments. Glucose and Orange II concentrations used in these experiments were 0.45, 0.90, 1.80 g l-1, and 40, 80, 120 mg l-1, respectively. The specific growth rate and decolorization rate of Orange II by E. faecalis were highest on the medium which contained at least 0.90 g l-1 glucose. It is necessary to note that glucose above 0.90 g l-1 gave no significant difference. On the medium containing 0.90 g l-1 glucose and 80 mg l-1 Orange II, E. faecalis grew with the highest specific growth rate (0.28 h-1) and Orange II decolorization rate (0.47 h-1). The maximum specific growth rate of biomass (μmax) and the halfsaturation coefficient (KS) under optimal conditions were 0.25 h-1 and 1.5 g.l-1, respectively. The kinetics of decolorization indicated that the process followed first order kinetics with respect to the initial concentration of Orange II. The inhibition constant (KI) was found to be 750 mg l-1 Orange II, indicating that Orange II concentration at e” 750 mg l-1 would inhibit bacterial growth to decolorize Orange II..

Products of Orange II Biodegradation by Enterococcus faecalis ID6017 and Chryseobacterium indologenes ID6016

Microbiology Indonesia Vol 1, No 2 (2007): August 2007
Publisher : Indonesian Society for microbiology

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Abstract

Chryseobacterium indologenes and Enterococcus faecalis were isolated from activated sludge of textile wastewater treatment plant. These bacteria had the ability to decolorize several azo-dyes. Degradation of azo dyes was initiated by decolorization (reduction of azo bond) which occurred in anaerobic condition. In this study, we focussed on biodegradation of Orange II by pure culture of C. indologenes ID6016 and E. faecalis ID6017, and to determine the metabolite products of Orange II degradation. The degradation of Orange II by both bacteria was carried out in batch experiments using liquid medium containing 80 mg/l Orange II, under sequential static agitated incubation. During the bacterial growth under static incubation (6 h), 66.1 mg/l Orange II were decolorized by 35.54 mg/l biomass of E. faecalis ID6017, but no decolorization found with C. indologenes ID6016. Based on HPLC results, the decolorized Orange II products were identified as sulfanilic acid and amino-naphthol. These metabolites were probably used or degraded by C. indologenes ID6016 under agitated incubation.