Biogenic synthesis of metal nanoparticles is of considerable interest, as it affords clean, biocompatible, nontoxic, and cost-effective fabrication. Driven by their ability to withstand variable extremes of environmental conditions, several microorganisms, notably bacteria and fungi, have been investigated in the never-ending search for optimal nanomaterial production platforms. Here, we present a hitherto unexplored algal platform featuring Chlorella pyrenoidosa, which offers a high degree of consistency in morphology of synthesized silver nanoparticles. Using a suite of characterization methods, we reveal the intrinsic crystallinity of the algae-derived nanoparticles and the functional moieties associated with its surface stabilization. Significantly, we demonstrate the antibacterial and photocatalytic properties of these silver nanoparticles and discuss the potential mechanisms that drive these critical processes. The blend of photocatalytic and antibacterial properties coupled with their intrinsic biocompatibility and eco-friendliness make these nanoparticles particularly attractive for wastewater treatment.

Driven by the need to engineer robust surface coatings for medical devices to prevent infection and sepsis, incorporation of nanoparticles has surfaced as a promising avenue to enhance non-fouling efficacy. Microbial synthesis of such nanoscale metallic structures is of substantive interest as this can offer an eco-friendly, cost-effective, and sustainable route for further development. Here we present a Mucor hiemalis-derived fungal route for synthesis of silver nanoparticles, which display significant antimicrobial properties when tested against six pathological bacterial strains (Klebsiella pneumoniae, Pseudomonas brassicacearum, Aeromonas hydrophila, Escherichia coli, Bacillus cereus, and Staphylococcus aureus) and three pathological fungal strains (Candida albicans, Fusarium oxysporum, and Aspergillus flavus). These antimicrobial attributes were comparable to those of established antibiotics (streptomycin, tetracycline, kanamycin, and rifampicin) and fungicides (amphotericin B, fluconazole, and ketoconazole), respectively. Importantly, these nanoparticles show significant synergistic characteristics when combined with the antibiotics and fungicides to offer substantially greater resistance to microbial growth. The blend of antibacterial and antifungal properties, coupled with their intrinsic “green” and facile synthesis, makes these biogenic nanoparticles particularly attractive for future applications in nanomedicine ranging from topical ointments and bandages for wound healing to coated stents.

Biogenic silver nanoparticles (Ag NPs) have supple platforms designed for biomedical and therapeutic intervention. Utilization of Ag NPs are preferred in the field of biomedicines and material science research because of their antioxidant, antimicrobial, and anticancerous activity along with their eco-friendly, biocompatible, and cost-effective nature. Here we present a novel fungus Piriformospora indica as an excellent source for obtaining facile and reliable Ag NPs with a high degree of consistent morphology. We demonstrated their cytotoxic property, coupled with their intrinsic characteristic that make these biogenic nanoparticles suitable for the anticancerous activity. In vitro cytotoxicity of biologically synthesized Ag NPs (BSNPs) and chemically synthesized Ag NPs (SNPs) was screened on various cancer cell lines, such as Human breast adenocarcinoma (MCF-7), Human cervical carcinoma (HeLa), Human liver hepatocellular carcinoma (HepG2) cell lines and embryonic kidney cell line (HEK-293) as normal cell lines. The antiproliferative outcome revealed that the BSNPs exhibited significant cytotoxic activity against MCF-7 followed by HeLa and HepG2 cell lines as compared to SNPs. The blend of cytotoxic properties, together with green and cost-effective characteristics make up these biogenic nanoparticles for their potential applications in cancer nanomedicine and fabrication coating of ambulatory and non-ambulatory medical devices.