Evaluation of Antibacterial Activity and Characterization of Synthesized Biodegradable Copolymers.

Green copolymer Poly(MA-CA) was developed by the thermal condensation polymerization of monomers such as DL-Malic acid (MA) and Citric acid (CA). The copolymer of Poly(MA-CA) was synthesized by varying the ratio of MA and CA monomers with 1:0, 1:3, 1:1, 3:1 and 0:1, and their antibacterial properties were studied with respect to their activity onGram-positiveandGram-negativebacteria by the bacterial count method. Furthermore, the biocidal activity of the plain monomers was also investigated and compared to those of the copolymers. Synthesized copolymers show good antibacterial effects towards bothGram-positiveandGram-negativebacteria. The antimicrobial properties of the copolymers and the monomers were studied by varying the ratio of polymers, effect of polymer concentration and effect of pH. Results indicated that the antibacterial activity of the copolymers increased with MA content and polymer dose. At low content of MA (wt.%), the copolymers poly(MA-CA)(1:3) possessed a higher effect onGram-positivebacteriaBacillus cereus and Micrococcus luteusthanGram-negativebacteriaSalmonella and Shigella. The other copolymers with the ratio of 1:1 and 3:1 including MA homopolymer possesses 100% inhibition of both Gram-positive and Gram-negative bacteria under the conditions studied. The developed polymers were extensively characterized by Fourier transform infrared spectroscopy analysis, thermal gravimetric analysis, X-ray diffraction analysis and scanning electron microscope-energy dispersive spectroscopy to understand their physicochemical properties. [ABSTRACT FROM AUTHOR]