Biodegradation of 3-chlorobenzoate and 3-hydroxybenzoate by polyurethane foam immobilized cells of Bacillus sp. OS13. Issue 2 (June 2016)

• Record Type: Journal Article
• Authors: Mulla, Sikandar I.; Bangeppagari, Manjunatha; Mahadevan, Gurumurthy D.; Eqani, Syed Ali Musstjab Akber Shah; Sajjan, Dayanand B.; Tallur, Preeti N.; Megadi, Veena B.; Ninnekar, Harichandra Z.
• Is Part Of: Journal of environmental chemical engineering. Volume 4:Issue 2(2016:Jun.)
• Page Start: 1423
• Page End: 1431
• Publication Date: 2016-06
• Subjects: Biodegradation -- Bacillus sp. OS13 -- Response surface method (RSM) -- 3-Chlorobenzoate -- 3-Hydroxybenzoate -- Polyurethane foam (PUF); Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2016.02.027
• Languages: English
• ISSNs: 2213-2929

Abstract

Highlights: We proposed a pathway for the degradation of 3-CBA by B acillus sp. OS13. 3-CBA degradation occurs via 3-HBA to PCA with the release of chloride ions. PUF-immobilized organism degrades 3-CBA (4 mM and 10 mM) within 60 h. PUF-immobilized organism degrades 3-HBA (4 mM and 10 mM) within 60 h. Abstract: Due to widespread use, persistence and toxicity, 3-chlorobenzoate (3-CBA) is well-known as an environmental pollutant. Bacillus sp. OS13, isolated as a 2-nitrotoluene tolerant, has the ability to utilize 3-CBA (4 mM) as a sole source of carbon and energy. Nevertheless, this organism has also simultaneously utilized the 4-chlorophthalate, 3-hydroxybenzoate, protocatechuate and 2-chlorobenzoate as a growth substrate. In order to achieve our study objective, firstly we followed the response surface methodology (RSM), and assessed the optimal growth conditions of pH (7.20) and temperature (33 °C) for Bacillus sp. OS13 to degrade the 3-CBA. We also determined the two major degradation products (i.e., 3-hydoxybenzoate and protocatechuate) of 3-CBA by using HPLC and GC–MS. Additionally, the activities of 3-hydroxybenzoate-4-hydroxylase and protocatechuate 3, 4-dioxygenase enzymes in the cell-free extract were also observed. Thus, in Bacillus sp. OS13, 3-CBA was transformed into protocatechuate via 3-hydroxybenzoate with the release of chloride ions and thereby enter into the ortho -cleavage pathway. In addition, there was complete degradation of 3-CBA (4 mM) and 3-hydroxybenzoate (4 mM) by the polyurethane foam (PUF)-immobilized cells of Bacillus sp. within 60 h. Furthermore, when the initial concentrations of both substrates were increased to 10 mM, the same PUF-immobilized cells were degraded approximately 98% of both substrates within 60 h. Our findings would be very useful towards the environmental management of 3-CBA in the surrounding contaminated environment.