Bioactive Components from <i>Ampelopsis japonica</i> with Antioxidant, Anti-α-Glucosidase, and Antiacetylcholinesterase Activities

• Main Authors: Jia-Hua Liang (Author), Hsiang-Ru Lin (Author), Chang-Syun Yang (Author), Chia-Ching Liaw (Author), I-Chou Wang (Author), Jih-Jung Chen (Author)
• Format: Book
• Published: MDPI AG, 2022-06-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.
• Notes: 10.3390/antiox11071228; 2076-3921
• Keywords: <i>Ampelopsis japonica</i>; solvent extracts; bioactive compounds; antioxidants; anti-α-glucosidase; AChE inhibition; Therapeutics. Pharmacology; RM1-950
• Source: Antioxidants, Vol 11, Iss 7, p 1228 (2022)

The dried root of <i>Ampelopsis japonica</i> (Thunb.) Makino (<i>A. japonica</i>.) is a traditional medicine used to treat fever, pain, and wound healing. It exhibits anti-inflammatory, antitumor, antityrosinase, and antimelanogenic activities. In this paper, we used different solvent extracts from the root of <i>A. japonica</i> to determine their antioxidant activity. Acetone extract showed relatively strong antioxidant properties by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl (DPPH), superoxide radical scavenging activity, and ferric reducing antioxidant power (FRAP) assays. In addition, these extracts also showed significant α-glucosidase and acetylcholinesterase (AChE) inhibitory activities. Acetone extract significantly inhibited α-glucosidase with an IC₅₀ value of 8.30 ± 0.78 μg/mL, and ethanol extract remarkably inhibited AChE with an IC₅₀ value of 37.08 ± 7.67 μg/mL. Using HPLC analysis and comparison with the chemical composition of various solvent extracts, we isolated seven active compounds and assessed their antioxidant, anti-α-glucosidase, and anti-AChE activities. Catechin (<b>1</b>), gallic acid (<b>2</b>), kaempferol (<b>3</b>), quercetin (<b>4</b>), resveratrol (<b>6</b>), and epicatechin (<b>7</b>) were the main antioxidant components in the root of <i>A. japonica</i>. According to the results of DPPH, ABTS, and superoxide radical scavenging assays, these isolates showed stronger antioxidant capacity than butylated hydroxytoluene (BHT). Moreover, <b>1</b>, <b>3</b>, <b>4</b>, euscaphic acid (<b>5</b>), <b>6</b>, and <b>7</b> also expressed stronger anti-α-glucosidase activity than the positive control acarbose, and all the isolated compounds had a good inhibitory effect on AChE. Molecular docking models and hydrophilic interactive modes for AChE assays suggest that <b>1</b> and <b>5</b> exhibit unique anti-AChE potency. This study indicates that <i>A. japonica</i> and its active extracts and components may be a promising source of natural antioxidants, α-glucosidase, and AChE inhibitors.