Studies on Endophytic Fungi of Calotropis Procera (L.) R.Br. with A View to Their Antimicrobial and Antioxidant Actvities Mediated by Extracellular Synthesised Silver Nanoparticles.

Abstract

Isolation and characterisation of four predominant endophytic bacteria namely, Pencillium sp., Alternaria sp., Aspergillus sp. and Cladosporium sp. from different parts of Calotropis procera plant has been conducted in summer season. Among four isolated fungi Alternaria sp. exhibited the highest (33.33%) colonisation frequency followed by Penicillum sp. (16.66 %), Aspergillus sp.(8.33%) and Cladosporium sp. ( 8.33%). The production and evaluation of “green synthesised AgNPs” has been carried out with the use of fungal cell free extract of four endophytic fungi understudy. The synthesis of AgNPs has been detected by colour change of the solution follwed by UV -Visible spectroscopy and FTIR spectroscopy.The synthesis of AgNPs was maximum in Penicllium sp. followed by Alternaria sp. The antibacterial activity of four fungal cell free extract as well as with AgNPs has conducted against two pathogenic bacteria, E.coli and Bacillus subtilis. Among them Penicillium sp. shows significant antibacterial activity against E.coli rather than Bacillus subtilis. Total phenol content and antioxidant properties of four fungi revealed significant result. The maximum phenol content (83 μg/l) and maximum antioxidant assay (28 μg/ml) has obtained in fungal cell free extract of Alternaria sp.