In vitro α-amylase/α-glucosidase, cytotoxicity and radical scavenging potential of Hypoxis hemerocallidea synthesized magnesium oxide nanoparticles

The prevalence of diabetes has continued to increase over the past decade. Medicinal extract-synthesized nanoformulations incorporating trace elements found in the body have emerged as alternative therapeutic technology for the treatment of diabetes. In this study, magnesium oxide (MgO) nanoparticles were prepared using Hypoxis hemerocallidea (HH) and investigated for their cytotoxicity, antioxidant, and antidiabetic potentials. MgO NPs were characterized by transmission electron microscopy (TEM), Fourier-transform infrared (FTIR) spectroscopy, and zeta-potential techniques. TEM analysis confirmed the 2D nanosheet-like morphology of the nanoparticles with particle size (diameter; 300 nm and length of about 1 µm) while the FTIR spectra showed functional groups correlating to the bioactive compounds of HH in the MgO NPs. Moderate antioxidant activity of MgO NPs was observed against DPPH (IC 50 = 57.35 ± 0.28 µg/mL) and ABTS (IC 50 = 52.08 ± 0.24 µg/mL). The nanoparticles were shown to be less toxic to normal embryonic (HEK293) and human liver (HEPG2) cell lines, with IC 50 of 48.63 ± 0.73 and 32.39 ± 0.95 µg/mL, respectively compared to a known cytotoxic drug, doxorubicin which exhibited IC 50 of 2.70 ± 0.32 and 8.62 ± 0.57 µg/mL respectively. Besides, the anti-hyperglycemic potential of the MgO NPs as demonstrated by α-amylase and α-glucosidase activities were significantly high with IC 50 values of 33.03 ± 1.43 and 52.38 ± 3.06 µg/mL, respectively. These results were compared with an FDA-approved antidiabetic reference standard Acarbose, which exhibited IC 50 values of 24.54 ± 1.55 and 6.54 ± 0.27 µg/mL. The results indicated that the HH bioinspired MgO NPs are capable of inhibiting meditators of diabetes and oxidative stress. This study further suggests that the MgO NPs synthesized using HH could be a good candidate for the management of diabetes and other inflammatory diseases due to their strong enzyme inhibition, efficient antioxidant properties, and biocompatibility.