CHIANG MAI UNIVERSITY JOURNAL OF NATURAL SCIENCES

Volume 20, No. 03, Month JULY, Year 2021, Pages 1 - 14

Antioxidant, ?-glucosidases and ?-amylase inhibitory activities of persicaria odorata

Kanya Thongra-ar, Piyanuch Rojsanga, Savita Chewchinda, Supachoke Mangmool, Pongtip Sithisarn

Abstract Download PDF

The objects of this study were to determine the effects to reactive oxygen species and antioxidant enzymes levels in HEK-293 cells and inhibition of α-glucosidases and α-amylase enzymes of extracts from Persicaria odorata or phak phaeo. The ethanol extracts from the leaves and the stems of phak phaeo were investigated for their 2,2-diphenyl-1-picryhydrazyl (DPPH) scavenging activities (IC50 were 7.74 ± 0.47 and 7.91 ± 0.43 µg/mL, respectively). Cellular antioxidant effects in human embryonic kidney-293 (HEK-293) cells with these extracts (0.1 mg/mL) also increased the mRNA expressions of manganese superoxide dismutase (Mn-SOD), glutathione peroxidase 1 (GPx-1), catalase and glutathione reductase (GRe). The leaf extract showed the higher efficacies in the induction of the mRNA expressions of Mn-SOD, GPx-1 and GRe while the stem extract exhibited a stronger effect to the induction of catalase. Phak phaeo in vitro inhibitory effects to α-glucosidase enzyme (IC50 values of 9.82 ± 1.64 and 13.99 ± 1.45 µg/mL, respectively and also strong inhibition to α-amylase with IC50 values of 90.66 ± 8.75 and 19.96 ± 5.37 µg/mL, respectively). Lineweaver-Burk plot demonstrated that phak phaeo extracts inhibited α-glucosidase and α- amylase in non-competitive manners. Total phenolic and total flavonoid contents were determined by Folin-Ciocalteu and aluminium chloride methods (the leaf and stem extracts were 22.89 ± 9.16 and 22.27 ± 8.77 g gallic acid equivalent in 100 g extract (g% GAE) and 7.20 ± 3.61 and 4.06 ± 1.73 g quercetin equivalent in 100 g extract (g% QE), respectively).

Keywords

Antioxidant enzymes, DPPH, HEK-293, MTT assay, Persicaria odorata, Reactive oxygen species, Total phenolic, Total flavonoid, ?-glucosidases, ?-amylase

---