Fungi fabrication, characterization, and anticancer activity of silver nanoparticles using metals resistant Aspergillus niger.

The purpose of this study was to assess the bio-fabrication possibilities of pre-isolated (from bauxite mine tailings) metal-tolerant Aspergillus niger biomass filtrate and the anticancer potential of synthesized silver nanoparticles (AgNPs) tested with a Human Cervical cancer cell line (HeLa cells: Henrietta Lacks cells). The nitrate reduction test demonstrated that A. niger has the ability to reduce nitrate, and filtrate derived from A. niger biomass efficiently fabricated AgNPs from AgNO3, as demonstrated by a visible color change from pale greenish to brownish. The UV-visible spectroscopy analysis revealed an absorbance peak at 435 nm, which corresponded to the AgNPs. These AgNPs have been capped and stabilized with several functional groups related to various bioactive molecules such as aldehyde, benzene rings, aldehydic, amines, alcohols, and carbonyl stretch protein molecules. Fourier-Transform Infrared Spectroscopy (FTIR) analysis confirmed the capping and stabilizing chemical bonding pattern. Scanning Electron Microscopy (SEM) revealed that the synthesized AgNPs were spherical, with an average size of 21.38 nm. This bio-fabricated AgNPs has in-vitro anticancer potential when tested against the HeLa cell line due to its potential size and shape. At 100 g mL-1 concentrations of this bio-fabricated AgNPs, the anticancer activity percentage was found to be 70.2%, and the IC50 value was found to be 66.32 g m-1. These findings demonstrated that the metal-tolerant A. niger cell filtrate could produce AgNPs with anticancer potential.