Fabricated loofah sponge supported indigenous tannery effluent Proteus mirabilis bacteria – A Strategy for Heavy Metal Removal

The widespread contamination of heavy metals caused by anthropogenically introduced acidic tannery effluent into the environment poses a threat to living organisms. This paper presents the first scientific study of chromium, copper and nickel detoxification using novel fabricated loofah sponges immobilized with indigenous organisms. The antibiotic susceptibility test revealed that the indigenous organism isolated was susceptible and intermediate to 30 tested antibiotics. The strains identified include Proteus mirabilis R10SANT [PQ069783], Proteus mirabilis MPE4069 [PQ069764.1], Proteus mirabilis  R4SANT [PQ069776.1] and Proteus mirabilis R8SANT [PQ069781.1], all demonstrating good heavy metal detoxification potential. Chromium, copper and nickel degradation reached 79.03%, 89% and 75.35% for free cells at a dose of 150 ppm and further increased to 85.40%, 91.2% and 80.90% at a dose of 200 ppm. Increased adsorption of chromium, copper and nickel was demonstrated by the immobilized strain in innovative modified loofah sponges, reaching levels of 175.1, 184.56 and 168.02 mg/g; at 200 ppm dose, this increased by 2.51%, 1.8% and 3.7%, respectively. This study confirms heavy metal detoxification by a novel modified loofah sponge supported by indigenous organisms, suggesting its potential application in tanneries and other heavy metal-contaminated sites.