doi:10.1038/nindia.2012.132 Published online 14 September 2012
Researchers have developed a new kind of antibiotic cotton by coating the fabric with nanoparticles loaded with leaf extracts of India basil 'tulsi' (Ocimum sanctum). Cotton fabrics coated with tulsi-loaded sodium alginate chitosan nanoparticles stifle the growth of disease-causing bacteria and fungi. Such fabrics could be used to make scrubs to check the spread of infectious diseases.
The re-emergence of resistant microorganisms along with the difficulty of achieving sustained release of antimicrobial agents from cotton fabrics has been an issue for medical profesionals.
To overcome them, researchers prepared extracts from tulsi leaves. A methanol-based extract proved most effective in inhibiting the growth of four bacteria — Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa — and two fungi — Aspergillus niger and Penicillium sp. They prepared sodium alginate chitosan nanoparticles and loaded them with the methanolic extract of tulsi leaves.
The leaf extract-loaded nanoparticle-coated cotton fabrics showed 100% inhibition of all test microorganisms except E. coli. In laundry tests, coated cotton fabrics retained antibacterial activity for 20 washes.
The researchers say that the antimicrobial compounds present in leaf extract attach to the fiber surface by forming bonds. The compounds then permeate and rupture the cell walls of microorganisms, resulting in leakage of cellular metabolites. This stops the reproduction of the microorganisms.
The authors of this work are from: PG & Research Department of Microbiology, PSG College of Arts & Science, Coimbatore, Tamil Nadu & Defence Bioengineering and Electromedical Laboratory, Bangalore, Karnataka, India; and Budapest University of Technology and Economics, Hungary.