This research aims to study the biogenic synthesis and characterization of Hypecoum pendulum extract-induced silver nanoparticles (HP-AgNPs) and to investigate its antioxidant, anti-alpha-amylase, and anti-acetylcholinesterase (AChE) activities. UV spectrometry at 417 nm with an surface plasmon resonance (SPR) peak of 1.54 confirmed the biosynthesis of HP-AgNPs. X-ray diffraction (XRD) analysis demonstrated that HP-AgNPs are crystalline with a 36 nm size. The average size of 80 nm was confirmed by scanning electron microscopy (SEM) analysis. The functional moieties bearing compounds accountable for the encapsulation and stability of HP-AgNPs were assessed by the Fourier transform infrared (FTIR) technique. Energy dispersive X-ray (EDX) demonstrated that silver was the main element (49%) of HP-AgNPs. HP-AgNPs showed the promising antioxidant potential of ABTS (71.57%), diphenyl-1-picrylhydrazyl (DPPH, 69.46%), H 2 O 2 (66.94%), ferric chloride (73.71%), and ammonium molybdenum (65.7%). HP-AgNPs exhibited significant enzymatic inhibition potential with IC 50 of 48.8 ± 4.03 μg/mL (α-amylase) and 51.78 ± 3.16 μg/mL (AChE). Kinetics studies showed that HP-AgNPs produced mixed-type inhibition against α-amylase (K m increased from 40.65 to 131.44%, whereas V max decreased from 4.14 to 9.77%) and non-competitivetype inhibition (V max decreased from 17.05 to 62.03% and K m remain constant) against AChE. Finally, it may be concluded that HP-AgNPs may possess anti-Alzheimer, anti-diabetic, and antioxidant capabilities.

The synthesis of silver nanoparticles (AgNPs) by the green method is favored as compared to chemical synthesis due to their appreciable properties of less toxicity and simple synthesis. The current study designed the biosynthesis of AgNPs in one step by using the plant Kickxia elatine (KE) extract and then investigated its inhibiting activity against rat’s brain acetylcholinesterase (AChE) ex vivo. Ultraviolet spectrum at 416 nm confirmed the formation of AgNPs. X-ray diffractometer calculated size was reported to be 42.47 nm. The SEM analysis confirmed spherical-shaped AgNPs. FT-IR suggested that the phytochemical groups present in the KE extract and their nanoparticles (NPs) are responsible for the biosynthesized of NPs. EDX analysis presented that Ag was the chief element with 61.67%. Both KE extract and AgNPs showed significant anti-AChE activity at 175 µg·mL−1. Statistical analysis showed that both KE and AgNPs exhibited non-competitive type inhibition against AChE, i.e. V max decreased (34.17–68.64% and 22.29–62.10%), while K m values remained constant. It is concluded that KE and AgNPs can be considered an inhibitor of rats’ brain AChE. Furthermore, the synthesis of AgNP-based drugs can be used as a cheaper and alternative option against diseases such as Alzheimer’s disease.