Main Article Content
Abstract
Silver nanoparticles (AgNPs) synthesized through biological methods have emerged as a difficult alternative to traditional chemical synthesis due to their increased biocompatibility and environmental attainability. In this study, we investigated the stability and various biological activities of AgNPs synthesized using Bacillus flexus B-AgNPs. The solidification of the nanoparticles was monitored for one month using UV-Vis spectroscopy, which revealed consistent surface plasmon resonance (SPR) peaks around 430-450 nm, indicating sustained nanoparticle integrity. The synthesized B-AgNPs proved significant antifungal, antibacterial, and antioxidant activities. The antifungal efficacy was evaluated against multiple strains of Alternaria solani with B-AgNPs showing superior inhibition compared to standard antifungal drugs. Even at low concentrations, the nanoparticles demonstrated powerful inhibitory effects on Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. Results indicate that B-AgNPs exhibit antioxidant activity also approximate to that of DPPH, particularly at higher concentrations (50 ppm), where the scavenging activity of B-AgNPs is nearly the same as that of DPPH. These findings indicate that B-AgNPs synthesized using B. flexus possess important potential uses in agriculture and biomedicine, with superior stability and biological activity compared to conventional methods.
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References
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- Ahmed, S., Ahmad, M., Swami, B. L., & Ikram, S. (2016). Green synthesis of silver nanoparticles using Azadirachta indica aqueous leaf extract. Journal of radiation research and applied sciences, 9(1), 1-7.
- Ahmed, S., Saifullah, Ahmad, M., Swami, B. L., & Ikram, S. (2016). Green synthesis of silver nanoparticles using Azadirachta indica aqueous leaf extract. Journal of Radiation Research and Applied Sciences, 9(1), 1-7. DOI: https://doi.org/10.1016/j.jrras.2015.06.006
- Alavi, M., & Karimi, N. (2020). Biosynthesis of Ag and Cu NPs by plant extracts and their biomedical applications: A review. Appl. Microbiol. Biotechnol., 104, 7741–7758.
- Al-Gburi, S. A. M. (2018). Green synthesis of silver nanoparticles.
- Ali, M. M., Kumar, A., & Ahmed, S. (2023). Evaluation of antifungal potential of biosynthesized silver nanoparticles against phytopathogenic fungi. Environmental Science and Pollution Research.
- Baker, C., Pradhan, A., Pakstis, L., Pochan, D. J., & Shah, S. I. (2014). Synthesis and antibacterial properties of silver nanoparticles. Journal of Nanoscience and Nanotechnology, 5(2), 244-249. DOI: https://doi.org/10.1166/jnn.2005.034
- Blois, M. S. (1958). Antioxidant determinations by the use of a stable free radical. Nature, 181(4617), 1199-1200. DOI: https://doi.org/10.1038/1811199a0
- Das, V. L., Thomas, R., Varghese, R. T., Soniya, E. V., Mathew, J., & Radhakrishnan, E. K. (2019). Extracellular synthesis of silver nanoparticles by the Bacillus strain CS 11 isolated from industrialized area. 3 Biotech, 4, 121-126. DOI: https://doi.org/10.1007/s13205-013-0130-8
- Dauthal, P., & Mukhopadhyay, M. (2016). In-vitro evaluation of antioxidant activity of synthesized silver nanoparticles using two cytotoxic drug compounds. Colloids and Surfaces B: Biointerfaces, 146, 599-607.
- El Sayed, M. T., & El-Sayed, A. S. (2020). Biocidal activity of metal nanoparticles synthesized by Fusarium solani against multidrug-resistant bacteria and mycotoxigenic fungi. Journal of Microbiology and Biotechnology, 30(2), 226. DOI: https://doi.org/10.4014/jmb.1906.06070
- Foldbjerg, R., Dang, D. A., & Autrup, H. (2011). Cytotoxicity and genotoxicity of silver nanoparticles in the human lung cancer cell line, A549. Archives of toxicology, 85, 743-750. DOI: https://doi.org/10.1007/s00204-010-0545-5
- Foldbjerg, R., Olesen, P., Hougaard, M., Dang, D. A., Hoffmann, H. J., & Autrup, H. (2011). PVP-coated silver nanoparticles and their influence on proinflammatory cytokines and chemokines in human monocyte cell line THP-1. Toxicology Letters, 208(3), 286-292.
- Gade, A., Gaikwad, S., Tiwari, V., Yadav, A., Ingle, A., & Rai, M. (2014). Biofabrication of silver nanoparticles using Aspergillus niger and its efficacy against human pathogenic fungi. Journal of Plant Biochemistry and Biotechnology, 23, 113-118.
- Ghorbani, H. R., Mehr, F. P., Pazoki, H., & Rahmani, B. M. (2011). Synthesis of silver nanoparticles using a simple and low-cost chemical reduction method. Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry, 41(10), 1054-1058.
- Gurunathan, S., Lee, K. J., Kalishwaralal, K., Sheikpranbabu, S., Vaidyanathan, R., & Eom, S. H. (2009). Antiangiogenic properties of silver nanoparticles. Biomaterials, 30(31), 6341-6350. DOI: https://doi.org/10.1016/j.biomaterials.2009.08.008
- Ibrahim, H. M. (2015). Green synthesis and characterization of silver nanoparticles using banana peel extract and their antimicrobial activity against representative microorganisms. Journal of radiation research and applied sciences, 8(3), 265-275.
- Ibrahim, H. M. (2015). Green synthesis and characterization of silver nanoparticles using banana peel extract and their antimicrobial activity against representative microorganisms. Journal of Radiation Research and Applied Sciences, 8(3), 265-275. DOI: https://doi.org/10.1016/j.jrras.2015.01.007
- Jo, Y. K., Kim, B. H., & Jung, G. (2009). Antifungal activity of silver ions and nanoparticles on phytopathogenic fungi. Plant disease, 93(10), 1037-1043. DOI: https://doi.org/10.1094/PDIS-93-10-1037
- Kalishwaralal, K., Deepak, V., Pandian, S. R., Kottaisamy, M., BarathManiKanth, S., & Kartikeyan, B. (2010). Biosynthesis of silver and gold nanoparticles using Bacillus licheniformis. Colloids and Surfaces B: Biointerfaces, 77(1), 257-262. DOI: https://doi.org/10.1016/j.colsurfb.2010.02.007
- Khalil, M. M., Ismail, E. H., El-Baghdady, K. Z., & Mohamed, D. (2014). Green synthesis of silver nanoparticles using olive leaf extract and its antibacterial activity. Arabian Journal of chemistry, 7(6), 1131-1139. DOI: https://doi.org/10.1016/j.arabjc.2013.04.007
- Kim, S. H., Lee, H. S., Ryu, D. S., Choi, S. J., & Lee, D. S. (2011). Antibacterial activity of silver-nanoparticles against Staphylococcus aureus and Escherichia coli. Korean Journal of Microbiology and Biotechnology, 39(1), 77-85.
- Kim, S. W., Jung, J. H., Lamsal, K., Kim, Y. S., Min, J. S., & Lee, Y. S. (2012). Antifungal effects of silver nanoparticles (AgNPs) against various plant pathogenic fungi. Mycobiology, 40(1), 53-58. DOI: https://doi.org/10.5941/MYCO.2012.40.1.053
- Kumar, A., Pathak, R. K., Sinha, R. P., & Anshu, A. (2021). Green synthesis of silver nanoparticles using leaf extract of Azadirachta indica and their antioxidant and antibacterial activities. Materials Today: Proceedings, 39, 1025-1029.
- Kumar, P., Sharma, V., & Singh, S. (2022). Biosynthesis and characterization of silver nanoparticles using Bacillus flexus. Materials Today: Proceedings, 47, 4072-4076.
- Lara, H. H., Romero-Urbina, D. G., Pierce, C., Lopez-Ribot, J. L., Arellano-Jiménez, M. J., & Jose-Yacaman, M. (2015). Effect of silver nanoparticles on Candida albicans biofilms: an ultrastructural study. Journal of nanobiotechnology, 13, 1-12. DOI: https://doi.org/10.1186/s12951-015-0147-8
- Ma, C., Borgatta, J., De La Torre-Roche, R., Zuverza-Mena, N., White, J. C., Hamers, R. J., & Elmer, W. H. (2019). Time-dependent transcriptional response of tomato (Solanum lycopersicum L.) to Cu nanoparticle exposure upon infection with Fusarium oxysporum f. sp. lycopersici. ACS Sustainable Chemistry & Engineering, 7(11), 10064-10074. DOI: https://doi.org/10.1021/acssuschemeng.9b01433
- Morones, J. R., Elechiguerra, J. L., Camacho, A., Holt, K., Kouri, J. B., Ramírez, J. T., & Yacaman, M. J. (2005). The bactericidal effect of silver nanoparticles. Nanotechnology, 16(10), 2346. DOI: https://doi.org/10.1088/0957-4484/16/10/059
- Prabhu, S., & Poulose, E. K. (2012). Silver nanoparticles: mechanism of antimicrobial action, synthesis, medical applications, and toxicity effects. International nano letters, 2, 1-10. DOI: https://doi.org/10.1186/2228-5326-2-32
- Priyadarshini, S., Gopinath, V., Priyadharsshini, N. M., MubarakAli, D., & Velusamy, P. (2013). Synthesis of anisotropic silver nanoparticles using novel strain, Bacillus flexus and its biomedical application. Colloids and Surfaces B: Biointerfaces, 102, 232-237. DOI: https://doi.org/10.1016/j.colsurfb.2012.08.018
- Rai, M. K., Deshmukh, S. D., Ingle, A. P., & Gade, A. K. (2012). Silver nanoparticles: the powerful nanoweapon against multidrug‐resistant bacteria. Journal of applied microbiology, 112(5), 841-852. DOI: https://doi.org/10.1111/j.1365-2672.2012.05253.x
- Singh, R., Shedbalkar, U. U., Wadhwani, S. A., & Chopade, B. A. (2015). Bacteriagenic silver nanoparticles: synthesis, mechanism, and applications. Applied microbiology and biotechnology, 99, 4579-4593. DOI: https://doi.org/10.1007/s00253-015-6622-1
- Sondi, I., & Salopek-Sondi, B. (2004). Silver nanoparticles as antimicrobial agent: a case study on E. coli as a model for Gram-negative bacteria. Journal of colloid and interface science, 275(1), 177-182. DOI: https://doi.org/10.1016/j.jcis.2004.02.012
References
Ahamed, M., AlSalhi, M. S., & Siddiqui, M. K. J. (2010). Silver nanoparticle applications and human health. Clinica Chimica Acta, 411(23-24), 1841-1848. DOI: https://doi.org/10.1016/j.cca.2010.08.016
Ahamed, M., Karns, M., Goodson, M., Rowe, J., Hussain, S. M., Schlager, J. J., & Hong, Y. (2011). DNA damage response to different surface chemistry of silver nanoparticles in mammalian cells. Toxicology and Applied Pharmacology, 233(3), 404-410. DOI: https://doi.org/10.1016/j.taap.2008.09.015
Ahmed, S., Ahmad, M., Swami, B. L., & Ikram, S. (2016). Green synthesis of silver nanoparticles using Azadirachta indica aqueous leaf extract. Journal of radiation research and applied sciences, 9(1), 1-7.
Ahmed, S., Saifullah, Ahmad, M., Swami, B. L., & Ikram, S. (2016). Green synthesis of silver nanoparticles using Azadirachta indica aqueous leaf extract. Journal of Radiation Research and Applied Sciences, 9(1), 1-7. DOI: https://doi.org/10.1016/j.jrras.2015.06.006
Alavi, M., & Karimi, N. (2020). Biosynthesis of Ag and Cu NPs by plant extracts and their biomedical applications: A review. Appl. Microbiol. Biotechnol., 104, 7741–7758.
Al-Gburi, S. A. M. (2018). Green synthesis of silver nanoparticles.
Ali, M. M., Kumar, A., & Ahmed, S. (2023). Evaluation of antifungal potential of biosynthesized silver nanoparticles against phytopathogenic fungi. Environmental Science and Pollution Research.
Baker, C., Pradhan, A., Pakstis, L., Pochan, D. J., & Shah, S. I. (2014). Synthesis and antibacterial properties of silver nanoparticles. Journal of Nanoscience and Nanotechnology, 5(2), 244-249. DOI: https://doi.org/10.1166/jnn.2005.034
Blois, M. S. (1958). Antioxidant determinations by the use of a stable free radical. Nature, 181(4617), 1199-1200. DOI: https://doi.org/10.1038/1811199a0
Das, V. L., Thomas, R., Varghese, R. T., Soniya, E. V., Mathew, J., & Radhakrishnan, E. K. (2019). Extracellular synthesis of silver nanoparticles by the Bacillus strain CS 11 isolated from industrialized area. 3 Biotech, 4, 121-126. DOI: https://doi.org/10.1007/s13205-013-0130-8
Dauthal, P., & Mukhopadhyay, M. (2016). In-vitro evaluation of antioxidant activity of synthesized silver nanoparticles using two cytotoxic drug compounds. Colloids and Surfaces B: Biointerfaces, 146, 599-607.
El Sayed, M. T., & El-Sayed, A. S. (2020). Biocidal activity of metal nanoparticles synthesized by Fusarium solani against multidrug-resistant bacteria and mycotoxigenic fungi. Journal of Microbiology and Biotechnology, 30(2), 226. DOI: https://doi.org/10.4014/jmb.1906.06070
Foldbjerg, R., Dang, D. A., & Autrup, H. (2011). Cytotoxicity and genotoxicity of silver nanoparticles in the human lung cancer cell line, A549. Archives of toxicology, 85, 743-750. DOI: https://doi.org/10.1007/s00204-010-0545-5
Foldbjerg, R., Olesen, P., Hougaard, M., Dang, D. A., Hoffmann, H. J., & Autrup, H. (2011). PVP-coated silver nanoparticles and their influence on proinflammatory cytokines and chemokines in human monocyte cell line THP-1. Toxicology Letters, 208(3), 286-292.
Gade, A., Gaikwad, S., Tiwari, V., Yadav, A., Ingle, A., & Rai, M. (2014). Biofabrication of silver nanoparticles using Aspergillus niger and its efficacy against human pathogenic fungi. Journal of Plant Biochemistry and Biotechnology, 23, 113-118.
Ghorbani, H. R., Mehr, F. P., Pazoki, H., & Rahmani, B. M. (2011). Synthesis of silver nanoparticles using a simple and low-cost chemical reduction method. Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry, 41(10), 1054-1058.
Gurunathan, S., Lee, K. J., Kalishwaralal, K., Sheikpranbabu, S., Vaidyanathan, R., & Eom, S. H. (2009). Antiangiogenic properties of silver nanoparticles. Biomaterials, 30(31), 6341-6350. DOI: https://doi.org/10.1016/j.biomaterials.2009.08.008
Ibrahim, H. M. (2015). Green synthesis and characterization of silver nanoparticles using banana peel extract and their antimicrobial activity against representative microorganisms. Journal of radiation research and applied sciences, 8(3), 265-275.
Ibrahim, H. M. (2015). Green synthesis and characterization of silver nanoparticles using banana peel extract and their antimicrobial activity against representative microorganisms. Journal of Radiation Research and Applied Sciences, 8(3), 265-275. DOI: https://doi.org/10.1016/j.jrras.2015.01.007
Jo, Y. K., Kim, B. H., & Jung, G. (2009). Antifungal activity of silver ions and nanoparticles on phytopathogenic fungi. Plant disease, 93(10), 1037-1043. DOI: https://doi.org/10.1094/PDIS-93-10-1037
Kalishwaralal, K., Deepak, V., Pandian, S. R., Kottaisamy, M., BarathManiKanth, S., & Kartikeyan, B. (2010). Biosynthesis of silver and gold nanoparticles using Bacillus licheniformis. Colloids and Surfaces B: Biointerfaces, 77(1), 257-262. DOI: https://doi.org/10.1016/j.colsurfb.2010.02.007
Khalil, M. M., Ismail, E. H., El-Baghdady, K. Z., & Mohamed, D. (2014). Green synthesis of silver nanoparticles using olive leaf extract and its antibacterial activity. Arabian Journal of chemistry, 7(6), 1131-1139. DOI: https://doi.org/10.1016/j.arabjc.2013.04.007
Kim, S. H., Lee, H. S., Ryu, D. S., Choi, S. J., & Lee, D. S. (2011). Antibacterial activity of silver-nanoparticles against Staphylococcus aureus and Escherichia coli. Korean Journal of Microbiology and Biotechnology, 39(1), 77-85.
Kim, S. W., Jung, J. H., Lamsal, K., Kim, Y. S., Min, J. S., & Lee, Y. S. (2012). Antifungal effects of silver nanoparticles (AgNPs) against various plant pathogenic fungi. Mycobiology, 40(1), 53-58. DOI: https://doi.org/10.5941/MYCO.2012.40.1.053
Kumar, A., Pathak, R. K., Sinha, R. P., & Anshu, A. (2021). Green synthesis of silver nanoparticles using leaf extract of Azadirachta indica and their antioxidant and antibacterial activities. Materials Today: Proceedings, 39, 1025-1029.
Kumar, P., Sharma, V., & Singh, S. (2022). Biosynthesis and characterization of silver nanoparticles using Bacillus flexus. Materials Today: Proceedings, 47, 4072-4076.
Lara, H. H., Romero-Urbina, D. G., Pierce, C., Lopez-Ribot, J. L., Arellano-Jiménez, M. J., & Jose-Yacaman, M. (2015). Effect of silver nanoparticles on Candida albicans biofilms: an ultrastructural study. Journal of nanobiotechnology, 13, 1-12. DOI: https://doi.org/10.1186/s12951-015-0147-8
Ma, C., Borgatta, J., De La Torre-Roche, R., Zuverza-Mena, N., White, J. C., Hamers, R. J., & Elmer, W. H. (2019). Time-dependent transcriptional response of tomato (Solanum lycopersicum L.) to Cu nanoparticle exposure upon infection with Fusarium oxysporum f. sp. lycopersici. ACS Sustainable Chemistry & Engineering, 7(11), 10064-10074. DOI: https://doi.org/10.1021/acssuschemeng.9b01433
Morones, J. R., Elechiguerra, J. L., Camacho, A., Holt, K., Kouri, J. B., Ramírez, J. T., & Yacaman, M. J. (2005). The bactericidal effect of silver nanoparticles. Nanotechnology, 16(10), 2346. DOI: https://doi.org/10.1088/0957-4484/16/10/059
Prabhu, S., & Poulose, E. K. (2012). Silver nanoparticles: mechanism of antimicrobial action, synthesis, medical applications, and toxicity effects. International nano letters, 2, 1-10. DOI: https://doi.org/10.1186/2228-5326-2-32
Priyadarshini, S., Gopinath, V., Priyadharsshini, N. M., MubarakAli, D., & Velusamy, P. (2013). Synthesis of anisotropic silver nanoparticles using novel strain, Bacillus flexus and its biomedical application. Colloids and Surfaces B: Biointerfaces, 102, 232-237. DOI: https://doi.org/10.1016/j.colsurfb.2012.08.018
Rai, M. K., Deshmukh, S. D., Ingle, A. P., & Gade, A. K. (2012). Silver nanoparticles: the powerful nanoweapon against multidrug‐resistant bacteria. Journal of applied microbiology, 112(5), 841-852. DOI: https://doi.org/10.1111/j.1365-2672.2012.05253.x
Singh, R., Shedbalkar, U. U., Wadhwani, S. A., & Chopade, B. A. (2015). Bacteriagenic silver nanoparticles: synthesis, mechanism, and applications. Applied microbiology and biotechnology, 99, 4579-4593. DOI: https://doi.org/10.1007/s00253-015-6622-1
Sondi, I., & Salopek-Sondi, B. (2004). Silver nanoparticles as antimicrobial agent: a case study on E. coli as a model for Gram-negative bacteria. Journal of colloid and interface science, 275(1), 177-182. DOI: https://doi.org/10.1016/j.jcis.2004.02.012