A facile green synthesis of manganese oxide nanoparticles using gum karaya polymer as a bioreductant for efficient photocatalytic degradation of organic dyes and antibacterial activity

• Published in: International journal of biological macromolecules 2024-07, Vol.273 (Pt 2), p.133123, Article 133123
• Main Authors: Nagaraja, Kasula, Arunpandian, Muthuraj, Tae Hwan, Oh
• Format: Article
• Language: English
• Subjects: Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - pharmacology; antibacterial properties; Antimicrobial activity; Azo Compounds - chemistry; Catalysis; Coloring Agents - chemistry; Congo red; Congo Red - chemistry; decolorization; Escherichia coli; Escherichia coli - drug effects; fabrics; Green Chemistry Technology; Green synthesis; gum karaya; Gum karaya polymer; irradiation; Karaya Gum - chemistry; Light; Manganese Compounds - chemistry; manganese monoxide; methyl orange; Nanoparticles; Nanoparticles - chemistry; Organic dyes; Oxides - chemistry; photocatalysis; Photocatalytic activity; Photolysis; polymers; remediation; Staphylococcus aureus; Staphylococcus aureus - drug effects; wastewater treatment; Water Pollutants, Chemical - chemistry; Water Purification - methods
• ISSN: 0141-8130; 1879-0003; 1879-0003
• DOI: 10.1016/j.ijbiomac.2024.133123

The release of organic dyes into water systems, mainly textile industries, poses a significant threat to human and animal health. This approach shows great potential for effectively removing harmful dyes and microorganisms from wastewater treatment for environmental remediation. This study utilized gum karaya polymer bio-reductant to synthesize manganese oxide (MnO2) nanoparticles through a green approach. The synthesized MnO2 nanoparticles were characterized and confirmed by various analytical techniques. These results revealed their nanoscale dimensions, morphology, chemical purity, crystal nature, decolorized intermediate, and band gap. The photocatalytic degradation of hazardous Congo red and methyl orange dyes using KRG-MnO2 nanoparticles under visible light irradiation. Furthermore, the results demonstrated that Congo red dye degradation efficiency of 93.34 % was achieved. The dye concentration (8 to 16 mg/L), pH concentration, and radical trapping were studied. This suggests that holes and hydroxyl radicals play a crucial role in degrading the Congo red dye and demonstrate superior recyclability after three successive cycles and good stability. The possible intermediates from the Congo red dye degradation were identified through LC-MS analysis. The polymer composite MnO2 NPs have displayed notable antibacterial activity against pathogenic bacteria such as Staphylococcus aureus and Escherichia coli. The research indicates that MnO2 nanoparticles functionalized with polymers can efficiently remove pathogens and organic dyes from diverse industrial water treatment processes. Schematic presentation of green synthesized MnO2 nanoparticles for photocatalytic degradation and antimicrobial activity. [Display omitted]