Abstract:
Methicillin-Resistant Staphylococcus aureus (MRSA) is responsible for nosocomial infections
and become resistant to most of the antibiotics commonly used. Therefore scientists have taken
an extra effort to invent new anti-MRSA antibiotics. However, prevention of the spread of
microorganisms is one of the best ways to control nosocomial infections. Silver metal has been
used as an antimicrobial agent since ancient times, hence, the development of an effective
disinfectant using nanosilver could be an innovative approach to fight against drug-resistant
Staphylococci. Therefore the present study aimed at the development of a nanosilver preparation
using aqueous extract of Cyprus rotundus (Kalanduru) and evaluation of its antibacterial and
disinfectant potency. C.rotundus is widely employed in folk medicine as an antiseptic and also
to treat wounds. Here, an aqueous extract of C.rotundus whole plant was prepared and the
antimicrobial sensitivity test was carried out against S. aureus. The crude extract did not show
any antibacterial activity. This extract was then utilized for the green synthesis of silver
nanoparticles (AgNPs). The formation of metal nanoparticles was monitored by the
measurement of the absorbance of the reaction mixture at different time intervals for a period of
72hrs. The silver nano-preparation displayed a high absorbance in the range of 240-260 nm and
420- 440 nm and the absorbance of the reaction mixture increased with time. The scanning
electron microscopy (SEM) images confirmed that preparation contains silver nanoparticles of
<10 nm size. The preparation was dried by a hot air oven and the antimicrobial activity and
Minimum Inhibition Concentration (MIC) of the AgNPs were evaluated. MIC of the preparation
was determined as 31.25 μg/mL against S. aureus and all five different MRSA strains. Further,
the disinfectant activity of the nanopreparation was calculated by conducting a disinfectant assay
on rough and smooth surfaces. The mean disinfectant activity of the preparation on rough and
smooth surfaces was determined as >99% and >90% respectively. Therefore biogenic silver
nanoparticles synthesised from an aqueous extract of C. rotundus. show great promise to be
developed into a commercial disinfectant.
