The Effectiveness of Pseudomonas aeruginosa in Degrading BiochemicalOxygen Demand and Chemical Oxygen Demand inSmall Island Domestic Wastewater

Abstract

The high organic content of domestic wastewater on small islands increases the risk of environmental pollution and
the spread of disease. Limited resources and infrastructure exacerbate waste management challenges in these areas. This study aims to identify local bacteria from domestic wastewater and test the effectiveness of Pseudomonas aeruginosa in degrading BOD and COD. This study was conducted in the Spermonde Islands, Makassar City. Wastewater samples were collected from six locations and analyzed using the MALDI-TOF MS test. Effectivenesstests were carried out in a simple 5 L ex situ bioreactor using a completely randomized design (CRD) with two factors: bacterial inoculum concentration (0%, 5%, 10%, 15%) and incubation time (2, 4, 6, 8 days). Pseudomonas aeruginosa effectively reduced BOD by 64 - 77% and COD by 63 - 77%. Variations in inoculum concentration did not significantly affect BOD and COD reduction (p > 0.05), while incubation time had a significant effect (p < 0.05). The highest removal efficiency occurred on day 6. These findings suggest that optimizing incubation time is more critical than increasing inoculum concentration for successful bioremediation. Pseudomonas aeruginosa is a practical and economical option to support sustainable wastewater management on small islands and can be integrated into household-scale communal wastewater treatment plants (WWTPs) to improve treatment effectiveness.