Synthesis, characterization, cytotoxicity, and antimicrobial studies of green synthesized silver nanoparticles using red seaweed Champia parvula

Phytochemical substances in seaweeds have a wide range of pharmacological properties and are involved in a unique eco-friendly technique to produce stable, less harmful metal nanoparticles. The antioxidant-rich phytochemical elements in red seaweed Champia parvula extract have garnered attention for their potential functions in the prevention of human diseases. This research explores the phytoconstituent contents of C. parvula aqueous extract as well as its ability to synthesize silver nanoparticles, and its antioxidant, antimicrobial, and anticancer properties are investigated. The seaweed extract was analyzed for total phenols (2.02 ± 0.11 mg/g), flavonoids (1.72 ± 0.05 mg/g), tannins (1.55 ± mg/g), anthocyanin (0.79 ± 0.21 mg/g), and total chlorophyll (0.7 ± 0.04 mg/g) contents. The biosynthesized C. parvula- mediated silver nanoparticles (Cp-AgNPs) were characterized by various spectroscopic techniques. The surface plasmonic resonance (SPR) band of Cp-AgNPs was observed at 425 nm using UV spectroscopy. The face-centered cubic (FCC) and crystalline structure were identified by X-ray diffraction (XRD) analysis. Scanning electron microscopy (SEM) confirmed the morphology of Cp-AgNPs as round in shape with 79 nm size. The biomolecules in the algae extract and Cp-AgNPs were identified with the help of FT-IR analysis, which confirms the presence of phenolic, proteins and amine compounds. Zeta potential analysis proved that the biosynthesized Cp-AgNPs were extremely stable due to the surface charge of nanoparticles (− 35.2 mV). The Cp-AgNPs showed greater free radical scavenging ability due to the presence of bioactive molecules such as phenols, flavonoids, tannins, and anthocyanin in algae extract. Cp-AgNPs exhibited the highest antimicrobial activity against Streptococcus mutans , Staphylococcus aureus , and Candida albicans at 100 μg/mL. Furthermore, Cp-AgNPs demonstrated anticancer activity against human lung (A549) cancer and colon (HT-29) cancer cells. The half-maximal inhibitory for lung cancer was found at 21.54 μg/mL, and for colon cancer it was found at 42.36 μg/mL. These findings confirmed that the synthesized Cp-AgNPs have a wide range of pharmacological activities and might be used as target drug carriers.