Table of Contents
Journal of Nanoparticles
Volume 2016, Article ID 4694367, 13 pages
Research Article

Screening Antimicrobial Activity of Nickel Nanoparticles Synthesized Using Ocimum sanctum Leaf Extract

1Department of Biochemistry, Manonmaniam Sundaranar University, Tirunelveli, Tamil Nadu 627012, India
2Department of Biotechnology, Science Campus, Alagappa University, Karaikudi, Tamil Nadu 630 004, India

Received 19 October 2015; Accepted 15 February 2016

Academic Editor: Tapas Sen

Copyright © 2016 Chitra Jeyaraj Pandian et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Antimicrobial efficacy of nickel nanoparticles synthesized using leaf extract of Ocimum sanctum (NiGs) was investigated against pathogenic Gram-negative (E. coli, K. pneumoniae, and S. typhi), Gram-positive (B. subtilis, S. epidermidis) bacteria and fungi (C. albicans, C. tropicalis, A. fumigatus, A. clavatus, and A. niger). 100 µg/mL NiGs showed maximum antimicrobial activity against tested pathogens compared to leaf extract and antibiotics. E. coli (25 mm) and C. albicans (23 mm) exhibited higher zone of inhibition at 100 µg/mL NiGs. MIC, MBC, and MFC values of NiGs against all tested pathogens ranged between 25 and 50 µg/mL. Growth of bacterial and fungal cells (105 cfu/mL) was completely inhibited at 50 µg/mL NiGs. E. coli and C. albicans have showed strong antimicrobial activity with 81% and 50% reactive oxygen species (ROS) production, 30 and 16 µg/mL protein leakage, and 95 and 82 U/L LDH leakages, respectively. Gram-negative bacteria and Candida species showed more sensitivity to NiGs at all concentrations tested (25–100 µg/mL) than Gram-positive bacteria and Aspergillus species, respectively. Microbial growth in the presence of NiGs and ascorbic acid confirmed the involvement of ROS in antimicrobial activity. Hence, NiGs induced ROS generation was attributed to the protein and LDH leakage from microbial membranes.