Assessing the Antibacterial and Antioxidant Potentials of Nickel Nanoparticles Fabricated via C. Procera Leaf Extraction
Main Article Content
Abstract
The green synthesis of nanoparticles using plant-based biomolecules provides an eco-friendly and sustainable alternative to conventional chemical methods, while also addressing pressing global concerns such as antimicrobial resistance and oxidative stress–related diseases. In this study, nickel nanoparticles (NiNPs) were synthesized using aqueous leaf extract of Calotropis procera, and their physicochemical properties, antibacterial potential, and antioxidant activities were evaluated. UV–Vis spectroscopy confirmed nanoparticle formation with a red-shifted absorption band at ~360 nm compared to the leaf extract control (276 nm). FTIR spectra revealed hydroxyl, carbonyl, and phenolic groups as key reducing and stabilizing agents, while XRD analysis indicated a structural transition from semi-crystalline plant constituents to highly crystalline nickel-based nanostructures. Antibacterial assays against six clinically relevant pathogens (Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi, and Clostridium spp.) demonstrated dose-dependent inhibition, with NiNPs consistently outperforming the crude extract. Minimum inhibitory and bactericidal concentration values for NiNPs (12.5 and 25 mg/mL, respectively) confirmed broad-spectrum bactericidal activity. Antioxidant analysis using the DPPH assay further showed that NiNPs exhibited strong radical scavenging capacity (IC₅₀ = 3.78 mg/mL), surpassing the crude extract (IC₅₀ = 8.81 mg/mL). These results highlight the synergistic effects of phytochemicals and nanoscale nickel, yielding enhanced antibacterial and antioxidant properties. Overall, C. procera-mediated NiNPs represent promising eco-friendly nanomaterials with potential applications in biomedical, pharmaceutical, and environmental fields. Future studies should focus on in vivo validation, toxicity profiling, and synergistic interactions with conventional therapeutics.
Article Details

This work is licensed under a Creative Commons Attribution 4.0 International License.
Adekunle, B., and Fayemi, O. (2024). Spectroscopic and antibacterial activities of cobalt and nickel nanoparticles: A comparative analysis. Journal of Analytical Science and Technology. Advance online publication. https://doi.org/
Agrawal, K. K., and Murti, Y. (2024). Characterization by LC-MS/MS and antioxidant activity of fractions of Calotropis procera leaves. International Journal of Pharmaceutical Sciences and Nanotechnology, 17(1), 7130–7152. DOI: https://doi.org/10.37285/ijpsn.2024.17.1.4
Ahmad Nejhad, A., Farhadi, N., and Shokri, D. (2023). Identification of phytochemical constituents and antimicrobial activities of Calotropis procera. Scientific Reports, 13, 15123. https://doi.org/10.1038/s41598-023-41825-0 DOI: https://doi.org/10.1038/s41598-023-42086-1
Al-Rowaily, S. L., Abd-ElGawad, A. M., Alqahtani, A. S., Assaeed, A. M., El-Amier, Y. A., Abd-ElGawad, A. M., and Elshamy, A. I. (2020). Polyphenol profiling and antimicrobial activity of Calotropis procera leaf essential oil. Plants, 9(4), 451. https://doi.org/10.3390/plants9040451 DOI: https://doi.org/10.3390/plants9040451
Amini, M., Farsi, M., and Karimi, M. (2022). Phytochemical profiling, salt-impurity removal, and in vitro antimicrobial activity of Calotropis procera. South African Journal of Botany, 147, 925–935. https://doi.org/10.1016/j.sajb.2022.01.028 DOI: https://doi.org/10.1016/j.sajb.2022.01.028
Amini, M., Shakeri, A., Karami, A., and Moradkhani, S. (2022). Phytochemical profiling and in vitro antimicrobial and antioxidant activity of Calotropis procera. South African Journal of Botany, 146, 399–408. https://doi.org/10.1016/j.sajb.2021.11.021 DOI: https://doi.org/10.1016/j.sajb.2021.11.021
Arekemase, M. O., Oyeyi, T. I., and Bala, A. S. (2013). Assessment of bitter leaf (Vernonia amygdalina) and Calotropis procera on some pathogenic microorganisms. Journal of Microbiology Research, 3(1), 37–40. https://doi.org/10.5923/j.microbiology.20130301.07
Balouiri, M., Sadiki, M., and Ibnsouda, S. K. (2016). Methods for in vitro evaluating antimicrobial and antioxidant activity: A review. Journal of Pharmaceutical Analysis, 6(2), 71–79. https://doi.org/10.1016/j.jpha.2015.11.005 DOI: https://doi.org/10.1016/j.jpha.2015.11.005
Bao, Y., He, J., Song, K., Guo, J., and Zhou, J. (2021). Plant-extract-mediated synthesis of metal nanoparticles. Journal of Renewable Materials, 9(12), 2109–2132. https://doi.org/10.32604/jrm.2021.015454 DOI: https://doi.org/10.1155/2021/6562687
Brand-Williams, W., Cuvelier, M. E., and Berset, C. (1995). Use of a free radical method to evaluate antioxidant activity. LWT - Food Science and Technology, 28(1), 25–30. https://doi.org/10.1016/S0023-6438(95)80008-5 DOI: https://doi.org/10.1016/S0023-6438(95)80008-5
Cureus. (2024). Calotropis procera and the pharmacological properties of its aqueous leaf extract: A review. Cureus, 16(5), e60311. https://doi.org/10.7759/cureus.60311 DOI: https://doi.org/10.7759/cureus.60311
Din, M. I., Nabi, A. G., Rani, A., Aihetasham, A., and Mukhtar, M. (2018). Single-step green synthesis of stable nickel and nickel oxide nanoparticles from Calotropis gigantea: Catalytic and antimicrobial potentials. Environmental Nanotechnology, Monitoring and Management, 9, 29–36. https://doi.org/10.1016/j.enmm.2017.11.005 DOI: https://doi.org/10.1016/j.enmm.2017.11.005
Habeeb, A., Ibrahim, M. Y., and Suleiman, A. M. (2024). Calotropis procera and the pharmacological properties of aqueous leaf extract (CALE): A review. Journal of Herbal Medicine, 45, 100624. https://doi.org/10.1016/j.hermed.2023.100624 DOI: https://doi.org/10.7759/cureus.60354
Habib, S., Al Omar, S. Y., Samad, A., Alam, M. J., and Adnan, M. (2023). Antibacterial and cytotoxic effects of biosynthesized zinc and titanium nanoparticles using C. procera. Journal of Drug Delivery Science and Technology, 79, 104066. https://doi.org/10.1016/j.jddst.2022.104066 DOI: https://doi.org/10.1016/j.jddst.2022.104066
Ibrahim, M. Y., and Sulaiman, H. (2024). Coconut shell-derived green synthesised carbon nanotubes for clean-up of crude oil spills. Pure and Applied Chemistry. https://doi.org/10.1515/pac-2024-0207 DOI: https://doi.org/10.1515/pac-2024-0207
Ibrahim, M., Khan, A. A., and Al-Khedhairy, A. (2020). Plant-mediated synthesis of metal nanoparticles and their biological applications. Applied Sciences, 10(12), 4192. https://doi.org/10.3390/app10124192 DOI: https://doi.org/10.3390/app10124192
Jaivik, V., and Bhatnagar, P. (2023). Green synthesis of nickel nanoparticles: Structural, optical, and biological insights. Journal of Materials Research and Technology, 25, 3374–3386. https://doi.org/10.1016/j.jmrt.2023.05.184 DOI: https://doi.org/10.1016/j.jmrt.2023.05.184
Kalu, A. O., Egwim, E. C., Jigam, A. A., and Muhammad, H. L. (2022). Green synthesis of magnetite nanoparticles using Calotropis procera leaf extract and evaluation of its antimicrobial activity. Nano Express, 3(4), 045004. https://doi.org/10.1088/2632-959X/aca925 DOI: https://doi.org/10.1088/2632-959X/aca925
Kumar, V., Gupta, J., and Sharma, A. (2023). Structural and functional properties of plant-derived cellulose nanomaterials: XRD insights. Cellulose, 30(7), 4057–4072. https://doi.org/10.1007/s10570-023-05128-4
Mansur, Y. I., and Hafsat, A. (2024). Synthesis of activated charcoal from coconut shell for the removal of crude oil spill. African Journal of Advances in Sciences and Technology Research, 15(1). https://doi.org/10.62154/ca3axa83 DOI: https://doi.org/10.62154/ca3axa83
Molyneux, P. (2004). The use of the stable free radical diphenylpicrylhydrazyl (DPPH) for estimating antioxidant activity. Songklanakarin Journal of Science and Technology, 26(2), 211–219.
Moustafa, A. A., Alomary, M. N., Alharbi, N. S., and El-Ashry, S. H. (2022). Characterization of green-synthesized NiO-NPs from Ziziphus spina-christi. Green Processing and Synthesis, 11(1), 302–314. https://doi.org/10.1515/gps-2022-0031 DOI: https://doi.org/10.1515/gps-2022-0031
Moustafa, A. A., Al-Shehri, B. M., Al-Otibi, F. O., and Ameen, F. (2022). Characterization of green-synthesized NiO nanoparticles from Ziziphus spina-christi leaf extract and their biological activities. BioNanoScience, 12(1), 293–302. https://doi.org/10.1007/s12668-022-01028-3 DOI: https://doi.org/10.1007/s12668-022-01028-3
Murugan, K., Subashini, R., Sathiskumar, U., and Odukkathil, G. (2023). Calotropis procera flower extract for the synthesis of double-edged octahedral α-Fe₂O₃ nanoparticles via a greener approach: an insight into its structure–property relationship for Escherichia coli. New Journal of Chemistry, 47(24), 11584–11593. https://doi.org/10.1039/D3NJ01044A) DOI: https://doi.org/10.1039/D3NJ01044A
Rani, P., Rajasekaran, A., and Murugan, K. (2021). Green synthesis of nickel nanoparticles using Calotropis procera latex and their biomedical applications. Materials Today: Proceedings, 45, 3561–3566. https://doi.org/10.1016/j.matpr.2020.10.255 DOI: https://doi.org/10.1016/j.matpr.2020.10.255
Saddiq, A. A., Yusoff, M. M., Naqvi, S. A. R., Bakar, S. A., and Alhassan, A. M. (2022). Antimicrobial, antigenotoxicity, and characterization of Calotropis procera and its rhizosphere-inhabiting actinobacteria. Molecules, 27(10), 3123. https://doi.org/10.3390/molecules27103123 DOI: https://doi.org/10.3390/molecules27103123
Saher, O., Abbas, M., Khan, M., Awan, A., Shah, M., and Rehman, A. (2023). Soluble laticifer proteins from Calotropis procera as effective antimicrobial candidates. Frontiers in Microbiology, 14, 1142263. https://doi.org/10.3389/fmicb.2023.1142263 DOI: https://doi.org/10.1016/j.sjbs.2023.103659
Salunke, G. R., and Muley, G. G. (2015). Voltammetric and impedimetric behaviour of phytosynthesized nickel nanoparticles. Journal of Nanostructure in Chemistry, 5(2), 123–131. https://doi.org/10.1007/s40097-015-0146-1
Shafique, S., Ahmad, A., and Imran, M. (2021). Antibacterial potential of phytochemical-rich extracts of Calotropis procera. Journal of King Saud University – Science, 33(5), 101450. https://doi.org/10.1016/j.jksus.2021.101450 DOI: https://doi.org/10.1016/j.jksus.2021.101450
Shnawa, B. H., Hamad, S. M., Barzinjy, A. A., and Ahmed, M. H. (2022). Antioxidant, protoscolicidal, hemocompatibility, and antibacterial properties of green-synthesized NiO nanoparticles. Biosurface and Biotribology, 8(3), 200–211. https://doi.org/10.1049/bsb2.12045 DOI: https://doi.org/10.1049/bsb2.12045
Siddiqui, R. A., Simjee, S. U., Kabir, N., and Ateeq, M. (2013). Calotropis procera root extract has the capability to combat free radical mediated damage. International Journal of Molecular Sciences, 14(9), 17450–17460. https://doi.org/10.3390/ijms140917450
Sirelkhatim, A., Mahmud, S., Seeni, A., Kaus, N. H. M., Ann, L. C., Bakhori, S. K. M., Hasan, H., and Mohamad, D. (2015). Review on zinc oxide nanoparticles: Antibacterial activity and toxicity mechanism. Nano-Micro Letters, 7(3), 219–242. https://doi.org/10.1007/s40820-015-0040-x DOI: https://doi.org/10.1007/s40820-015-0040-x
Suresh, S., Jothi, L., and Gopi, S. (2021). XRD analysis of phytochemical-rich plant extracts and their nanomaterials. Materials Today: Proceedings, 45, 4835–4840. https://doi.org/10.1016/j.matpr.2020.12.581 DOI: https://doi.org/10.1016/j.matpr.2020.12.581
Tailor, G., Prajapati, P., and Chandel, S. (2023). A review on the green synthesis of nickel nanoparticles and their diverse applications. Environmental Research, 227, 115713. https://doi.org/10.1016/j.envres.2023.115713 DOI: https://doi.org/10.1016/j.envres.2023.115713
Tukur, M., Ibrahim, M. Y., and Abubakar, H. (2023). Phytochemical screening and antifungal studies of Tapinanthus globiferus growing on Balanites aegyptica. Journal of Biochemicals and Phytomedicine, 2(2), 75–81. https://doi.org/10.34172/jbp.2023.15
Villagrán, Z., Rocha, C., Martínez, R., and Soria, F. (2024). Plant-based extracts as reducing, capping, and stabilizing agents in nanoparticle synthesis. Resources, 13(6), 70. https://doi.org/10.3390/resources13060070 DOI: https://doi.org/10.3390/resources13060070
Wadhwani, A., Deshmukh, R., and Lahiri, S. (2021). A review on phytochemical constituents and pharmacological potential of Calotropis procera. Current Traditional Medicine, 7(3), 284–295. https://doi.org/10.2174/2215083806666210128143121
Yahaya, M. I., and Salihu, Z. (2024). Efficiency of green synthesised carbon nanotubes from Moringa oleifera leaf extract as potential toxic metals adsorbent in polluted water. Pure and Applied Chemistry. https://doi.org/10.1515/pac-2024-0103 DOI: https://doi.org/10.1515/pac-2024-0103