Exposure effects of non-ionizing radiation of radio waves on antimicrobial potential of medicinal plants

Abstract

The high frequency electromagnetic (EM) waves have been proven as potent environmental polluters. The radio towers are considerably increasing to cater to the growing telecommunication requirements. The presented research focuses on the investigation of EM waves on antimicrobial potential of pharmaceutically important medicinal plants viz. Tulsi (Ocimum sanctum L.) and Brahmi (Bacopa monnieri). The similar work has not been reported till date at the best of our knowledge. The medicinal plants were exposed to EM waves of 900 MHz possessing a 1.9 mG magnetic field. Our former investigation on plant physiology gave deteriorative effects on selected plants physiology in terms of growth, chlorophyll content, protein and carbohydrate content. In the presented article, the antimicrobial activity of two plants was inspected through various bacterial and fungal species. In case of B. monnieri, investigations revealed raise in Zone of Inhibition (ZOI) for both the bacterial and fungal strains in the range of 50%, whereas for O. sanctum increase of 63.26% and 59.42% ZOI for bacterial and fungal strains were noted respectively upon 24 h of exposure. Minimum Inhibitory Concentration (MIC) also decreased for 24 and 48 h of exposure. The transient raise in antimicrobial activity indicated the induction of plant defense system which can be considered as positive influence of short term radiation on medicinal properties of plants. Both plants exhibited the highest antimicrobial potential for E. coli and P. chrysogenum showing a prominent decline after 72 h of exposure. A substantial decline in antimicrobial in MIC of B. monnieri reported was 211% against E. coli and 166% against P. chrysogenum upon 144 h of exposure compared to control plants. The antimicrobial potential of O. sanctum was also decreased upon radiation, which is having a 392% reduction against E. coli and a 225% reduction against P. chrysogenum upon 144 h of exposure. The noteworthy deteriorative effects of radio waves on antimicrobial potential have been observed for both the medicinal plants.