In vitro antioxidant activities, α-glucosidase and acetylcholinesterase inhibition ability of Akebia trifoliata pulp extracts

【Objective】In order to provide a theoretical basis for the development and utilization of Akebia trifoliata, the in vitro antioxidant, α-glucosidase inhibition, and acetylcholinesterase inhibition ability of Akebia trifoliata pulp extract were investigated.【Method】The A. trifoliata pulp was extracted with ethanol, and the crude extract was further partitioned using different polarity solvents, where petroleum ether, chloroform, ethyl acetate, n-butanol phase extract and water residue were obtained. The in vitro antioxidant activity was evaluated using the DPPH radical scavenging ability, ABTS radical scavenging ability, ferric reducing antioxidant power, and oxygen radical absorbance ability. The α-glucosidase inhibition ability and acetylcholinesterase inhibition ability were carried out to quantify the potential of hypoglycemic effect and anti-Alzheimer effect.【Result】The petroleum ether phase extract exhibited the strongest DDPH radical scavenging ability with the value of 54.02 mg Trolox/g, and chloroform phase extract posed the strongest ABTS radical scavenging ability(320.66 mg Trolox/g) and oxygen radical absorbance ability(266.87 mg Trolox/g), while the crude extract showed the highest ferric reducing antioxidant power(557.36 mg FeSO₄/g). The chloroform phase extract showed the strongest α-glucosidase ability with the half inhibition concentration rate(IC₅₀) value of 0.93 mg/mL, and chloroform phase extract showed the strongest acetylcholinesterase inhibition ability, and IC₅₀ value was 1.22 mg/mL. The correlation analysis showed that the relationships among all antioxidant assay results were extremely significant(P<0.01), correlation coefficient range was 0.659-0.970, except the relationship between ABTS radical scavenging capacity and ferric reducing antioxidant power(P>0.05, the same below). The IC₅₀ of α-glucosidase inhibition ability had not significant correlation with four antioxidant abilities(correlation coefficient range was between-0.485 and-0.412). A significant negative correlation was found between the IC₅₀ of acetylcholinesterase inhibition ability and ferric reducing antioxidant power(correlation coefficient was-0.556, P<0.05), while there were no significant correlation with the DPPH radical scavenging ability, ABTS radical scavenging ability, and oxygen radical absorbance ability(correlation coefficient range was between-0.541 and-0.434). 【Conclusion】The above results indicate that A. trifoliata pulp extracts have certain in vitro antioxidant ability, α-glucosidase inhibition ability, and acetylcholinesterase inhibition ability. A. trifoliata has the potential to be developed as a natural antioxidant and healthy food with antidiabetic and anti-Alzheimer activity.