| Autor: |
Niloy MS; Department of Biochemistry and Molecular Biology, Jahangirnagar University, Savar, Dhaka 1342, Bangladesh., Hossain MM; Department of Biotechnology and Genetic Engineering, Jahangirnagar University, Savar, Dhaka 1342, Bangladesh., Takikawa M; Department of Advanced Science and Engineering, Waseda University (TWIns), Shinjuku-ku, Tokyo 162-8480, Japan., Shakil MS; Department of Biochemistry and Molecular Biology, Jahangirnagar University, Savar, Dhaka 1342, Bangladesh., Polash SA; Department of Biotechnology and Genetic Engineering, Jahangirnagar University, Savar, Dhaka 1342, Bangladesh.; Nano Biotechnology Research Laboratory (NBRL), School of Science, RMIT University, Melbourne, Victoria 3001, Australia., Mahmud KM; Department of Biochemistry and Molecular Biology, Jahangirnagar University, Savar, Dhaka 1342, Bangladesh., Uddin MF; Department of Biochemistry and Molecular Biology, Jahangirnagar University, Savar, Dhaka 1342, Bangladesh., Alam M; Department of Biochemistry and Molecular Biology, Jahangirnagar University, Savar, Dhaka 1342, Bangladesh., Shubhra RD; Department of Biotechnology and Genetic Engineering, Jahangirnagar University, Savar, Dhaka 1342, Bangladesh., Shawan MMAK; Department of Biochemistry and Molecular Biology, Jahangirnagar University, Savar, Dhaka 1342, Bangladesh., Saha T; Department of Textile Engineering, Dhaka University of Engineering and Technology, Gazipur 1707, Bangladesh.; School of Engineering, RMIT University, Melbourne, Victoria 3001, Australia., Takeoka S; Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University (TWIns), Shinjuku-ku, Tokyo 162-8480, Japan., Hasan MA; Department of Biochemistry and Molecular Biology, Jahangirnagar University, Savar, Dhaka 1342, Bangladesh., Ranjan Sarker S; Department of Biotechnology and Genetic Engineering, Jahangirnagar University, Savar, Dhaka 1342, Bangladesh. |
| Abstrakt: |
Among metallic nanoparticles, silver nanoparticles (AgNPs) have a wide spectrum of medical applications. Herein, biogenic silver nanoparticles (bAgNPs) were prepared from extracts of Caesalpinia digyna leaf as a reducing agent at different pH values ( i.e ., 5, 7, 8, and 10). The as-synthesized bAgNPs were characterized using UV-vis and Fourier transform infrared (FTIR) spectroscopies, scanning transmission electron microscopy, powder X-ray diffraction analysis, dynamic light scattering, and ζ-potential analysis. The sizes of bAgNPs prepared at pH 5, 7, 8, and 10 were 45.4, 11.3, 11.4, and 40.8 nm, respectively, and all of the nanoparticles were negatively charged. The antimicrobial activity of the as-prepared bAgNPs was investigated against Bacillus subtilis , Escherichia coli DH5α, E. coli K12, enteropathogenic E. coli (EPEC), and Salmonella typhi . The bAgNPs prepared at pH 8 showed the highest antibacterial propensity against all of the bacterial strains as exhibited in the zone of inhibition (ZOI) as well as the CellTox green assay, which can be due to their relatively small size, stability, and higher surface area-to-volume ratio. The bAgNPs synthesized at pH 8 showed the highest ZOI against B. subtilis , which was ∼25 mm in diameter. The lipid peroxidation assay demonstrated the formation of the malondialdehyde-thiobarbituric acid (MDA-TBA) adduct while treating the bacteria with bAgNPs due to the oxidation of fatty acids present in the membrane. The highest amount of MDA-TBA adduct was observed when Gram-positive B. subtilis was exposed to bAgNPs. On the contrary, rats treated with bAgNPs demonstrated no significant toxicity in terms of hematological and biochemical parameters. The bAgNPs also showed excellent compatibility with human red blood cells. Overall, bAgNPs synthesized at pH 8 have superior antimicrobial activity and excellent biocompatibility and, therefore, can be used as potential antibacterial agents. |
