Multi dye degradation and antibacterial potential of Papaya leaf derived silver nanoparticles

Abstract

The synthesis of nanoparticle using green approach is not only a simple process, but it is also an economical and ecofriendly way of obtaining variable shape and sized nanoparticles. The present study involves Carica papaya leaf extract for the synthesis of silver nanoparticles (Pa-AgNps). The UV–vis spectrum showed the absorbance peak of 468 nm. The TEM micrograph clearly highlighted the spherical shape of synthesized Pa-AgNps with size ranging from 10 to 70 nm, further EDS highlighted the presence of silver in the sample. In order to analyze the stability and average size of Pa-AgNps, Zeta potential and DLS were performed. The Zeta potential showed the value of −12 mV, indicating the high stability of synthesized Pa-AgNPs. The DLS highlighted the average size of 68 nm of synthesized Pa-AgNPs. Further, the antimicrobial activity of the Pa-AgNps along with few antibiotics (penicillin, kanamycin and chloramphenicol) was evaluated against E. coli and S. aureus. A synergistic effect was observed with AgNPs combined with antibiotics in Zone of inhibition assay. For E.coli and S. aureus, Pa-AgNPs + penicillin showed 0.77 and 0.72 increase in fold area, respectively. Further, an increase in fold area of around 1.04 and 0.26 was observed in E. coli and S. aureus, respectively, from Pa-AgNPs + kanamycin. Moreover, for Pa-AgNPs + chloramphenicol, an increase in fold area of 1.25 and 0.38 was observed against E. coli and S. aureus, respectively. In the dye degradation assay, ability of Pa-AgNps was studied for Blue CP and Yellow 3RS, the results showed effective degradation ability of Pa-AgNPs with 90 % and 83 % removal for Blue CP and Yellow 3RS, respectively at 50 mg/l of dye concentration. © 2020 Elsevier B.V.