ENZYME ACTIVITY OF CATECHOL 1, 2- DIOXYGENASE AND CATECHOL 2, 3-DIOXYGENASE PRODUCED BY Providencia vermicola STRAIN 13A_BEN AND Pseudomonads aeruginosa STRAIN 80A_BEN_NG

ABSTRACT

Polycyclic aromatic hydrocarbon is a natural compound consisting of carbon, hydrogen and other complexes. They are large organic compounds with 2 to 7 fused aromatic rings, low vapor pressure, high boiling point, high melting point and low aqueous solubility. This study was aimed at determining the enzymatic activity of catechol 1, 2-dioxygenase (C12O) and catechol 2, 3-dioxygenase (C23O) produced by Providencia vermicola strain 13A_Ben and Pseudomonas aeruginosa strain 80A_Ben_NG as a possible tool for PAHs degradation. The bacteria isolates were isolated from hydrocarbon polluted soil, characterized using molecular methods. Supernatant cell free extract of the bacteria isolates were obtained after growth on Tryptone Soya Broth (TSB) and Bushnell Haas broth (BHB) for 36 hours. Total protein were assayed using Randox kit and the formation of 2-hydroxymuconic semi-aldehyde was determined using meta cleavage results of catechol activity. Providencia vermicolar strain 13A_Ben and Pseudomonas aeruginosa strain 80A_Ben_NG produced catechol 1, 2-dioxygenase and catechol 2, 3-dioxygenase by the formation of cis, cis mucanonic acid and 2-hydroxymuconic semi-aldehyde. The medium used for the cultivation of these bacteria isolates were observed to influence the activity of C12O and C23O at pH 7.0 above 90% relative activity.The effect of temperature showed a relative decline on the activity of catechol 1, 2-dioxygenase and catechol 2, 3-dioxygenase produced by Providencia vermicola strain 13A_Ben. However, Pseudomonas aeruginosa strain 80A_Ben_NG showed potential to be utilize in degradation of PAHs as a result of the production of C12O and C23O.