Comprehensive Evaluation of the Biological Activities of Potentilla argyrophylla and Its Green‐Synthesized Silver Nanoparticles

Potentilla argyrophylla Wall. ex Lehm., a significant medicinal plant employed in Ayurveda, Siddha, Sowa‐Rigpa, and Chinese medicine, was collected from Kunzum Pass (altitude ∼ 4590 m), Spiti Valley, a UNESCO‐recognized Cold‐Desert Biosphere, Himachal Pradesh, India. The aerial parts were analyzed for phytochemical content, antioxidant, antimicrobial, and alpha‐amylase inhibitory activities, and employed phytofabrication of silver nanoparticles. Synthesized silver nanoparticles (PoSNPs) were characterized using UV spectroscopy, x‐ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, high‐resolution transmission electron microscopy, energy‐dispersive x‐ray spectroscopy, and selected area electron diffraction analyses. Antimicrobial potential was examined against Candida albicans MTCC 227, Bacillus cereus BCS1, Streptococcus mutans MTCC 890, and Escherichia coli MTCC 443. Total phenol content was higher in methanol extract, while acetone extract was richer in flavonoids and tannins. Both extracts possessed antimicrobial (highest MIC 625 µg/ml against S. mutans ), antioxidant (IC 50 76.14 and 58.69 µg/ml for acetone and methanol extracts, respectively), and alpha amylase inhibition (IC 50 2.08 and 5.41 mg/ml for acetone and methanol extracts, respectively) potentials. Notably, crystalline and almost spherical PoSNPs outperformed their parent extract in antimicrobial (MIC 3.91 µg/ml against S. mutans ) and antioxidant (IC 50 12.94 µg/ml) activities, highlighting their potential for biomedical applications.