Algal diversity of Yeldari dam isolation identification and biosynthesis of silver and gold nanoparticles and bioactivity of few species

Abstract

Yeldari dam was constricted on river Purna it is an example of lentic water ecosystem. Algae are structurally very simple group of organism ranging from unicellular to multicellular forms as well as they perform the key role in the ecosystem. The river Purna is the tributary of Godavari river. The present investigation was conducted from seven sites of Purna river basin. In this study total 111 algal species were recorded from three classes i.e. Chlorophyceae, Cyanophyceae and Bacillariophyceae. Maximum number of species was recorded from class Cyanophyceae with 50 algal specimens. The genus Navicula, Oscillatorai and Spirogyra was most dominant. Out of recorded algal taxa seven algal specimens were pure cultured in laboratory. Biosynthesis of silver and gold nanoparticles was done by using three algal strains i.e. Spirogyra dubica Kuetzing, Aphanocapsa grevillei (Hass.) Rabenh and Chrooccous minimus (Keissler) Lemm. newlineIn the Spirogyra dubica Kuetzing synthesis of silver nanoparticles was confirmed by colour change from yellow to reddish brown and the results were verified by UV-Vis spectroscopy, SEM, XRD, FTIR and NTA analysis. In Spirogyra dubica Kuetzing UV-visible spectra was observed at 428nm, the size of NPS was measured 60nm by NTA analysis, in the XRD analysis four characteristic peaks were observed at 32.85 0, 46.91 0, 63.79 0and 76.43 0 which corresponds to the (111), (200), (220) and (311) planes indicates that particles were crystalline in nature with 17.41nm to 61.52nm size and the SEM study shows that particles are spherical shape up to 100nm size. newlineIn the Chrooccous minimus (Keissler) Lemm the absorbance peak was observed at 426 nm, in the XRD study four characteristic peaks were appeared at 2and#952; values of 32.850, 42.470, 64.130 and 76.330 which show that NPs were crystalline in the nature and size was calculated 12.92nm-49nm in the form of peaks means. In the SEM analysis it was confirmed that particles were triangular and spherical in shape up to 100nm size. The FTIR peaks indicate that presences of P