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Five plant species namely, Phyllanthus acidus, Piper aduncum, Pandanus amaryllifolius, Macaranga peltata and Acacia mangium were analysed for their effective in-vitro bioactivity. The chloroform and aqueous extracted of the selected plants were subjected to TLC bioautography for antioxidant activity later all the extracted were subjected for DPPH assay where the chloroform extracts were found to express maximum antioxidant property. Amongst all the plants, Macaranga peltata accounted to 95% DPPH scavenging activity. The antimicrobial studies of the plant extracts were performed via agar well diffusion method, MIC determination, Biofilm inhibition assay in microtitre plate against clinical isolates like Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa. It was found that Piper aduncum (chloroform and aqueous extract) and Macaranga peltata (only aqueous) expressed antibacterial activity, of which only chloroform extract of Piper aduncum could show negative influence against the biofilm development of P.aeruginosa.

In this study, SPIONs were produced in the presence of cobalt as catalyst. SPIONs formed by this chemical co-precipitation were size around 20 nm. After producing the SPIONs, it was subjected for functionalization with oleic acid and loaded with drug-itraconazole (a drug possess antifungal and antibacterial activity) and encapsulated with polyhydroxybutyrate (PHB). The produced core-shell SPIONS was used for antimicrobial study against two bacteria namely-Pseudomonas aeruginosa and Brevibacillus brevis and a fungi-Candida albicans. It was found to be effectively releasing drug for more than 3 hours. The SPIONs alone was acting good as contrasting agent and used for enhancing X-ray imaging.

The aqueous extracts of Euphorbia hirta was used to synthesise silver nanoparticles using bioreduction method. The nanoparticles were characterised by UV Vis spectroscopic analysis, SEM, EDX, AFM, XRD analysis. The silver nanoparticles were also tested for antibacterial activity in Pseudomonas aeruginosa and Bacillus subtilis. The minimum inhibitory concentration for the synthesised nano particles were also tested against the two bacterial species for the least concentration of 0.5µg/mL. The swarming motility assay and protein leakage assay was also tested for the nanoparticle. The silver nanoparticles were found to be much effective.

Silver nano particles synthesised from the leaves of Wrightia tinctoria were characterised by following instrumental analysis -UV Vis spectroscopy, Scanning Electron Microscopy, Energy dispersive X-ray spectroscopy, Atomic force microscopy and X-ray diffraction. The interaction of the silver nanoparticle to the microorganism was studied in Pseudomonas aeruginosa and Bacillus subtilis through agar diffusion method, minimum inhibitory concentration, swarming motility assay and protein leakage assay. The nanoparticles were found to be more effective against the bacteria used in this study.