Congo Red Decolorization by Two Bacterial Isolates from Cal-Sag Channel Under Static Incubation and Intermittent Aeration

This study investigated the decolorization of Congo Red, an azo dye, by two bacterial isolates (CS-1 and CS-2) from the Cal-Sag Channel under static incubation and intermittent aeration. The objective was to evaluate whether intermittent aeration enhances decolorization efficiency with the hypothesis that intermittent aeration would enhance decolorization activity by promoting sequential microaerophilic-aerobic condition. This sequential treatment was hypothesized to prevent the accumulation of toxic byproducts of azo dye biodegradation, thus promoting growth and continued decolorization activity by the bacteria. Results showed that CS-1 was the most effective at reducing dye concentration, with no significant impact of intermittent aeration on decolorization or bacterial growth across all strains, thus rejecting the hypothesis. Findings suggest that CS-1 has potential for bioremediation applications, and its effective decolorization under static conditions may simplify treatment processes for azo dye polluted waters.