Preliminary investigation of Nauclea latifolia ripe fruits for antioxidant and antidiabetic activities

Abstract

Fruits of Nauclea latifolia (Family Rubiaceae) have been used as food and medicinal plants. The ethnomedicinal reports indicated that it can be traditionally used for the treatment of dysentery, diarrhea, diabetes, malaria etc. The aim of this work was to evaluate the antioxidant, α–amylase and α–glucosidase activities of methanol extract of N. latifolia fruits at varying concentrations (20-100 µg/ml) using standard methods. The results of the DPPH and nitric oxide free radical scavenging capacity showed IC50 values 92.0µg/ml and 30.0µg/ml respectively indicating a good inhibitory capacity but lesser when compared to the standard, ascorbic acid which are < 10.0µg/ml and < 20.0µg/ml respectively. The analysis shows total phenolic contents of 147.9±3.35mg/g and ferric reducing antioxidant potential of 1604.1±9.20mg/g supporting the fact that phenolics are highly potent antioxidants. Based on the results obtained from α–amylase and α–glucosidase inhibition, the IC50 > 100µg/ml showing a lesser inhibitory activity when compared to the standard Acar-bose with IC50 values of 50.1µg/ml and 44.0µg/ml respectively. The results clearly indicate that the methanol extract of N. latifolia has a moderate free radical scavenging activity resulting from various interaction between different components of the plant. It can be concluded that the fruits may provide natural source of bioactive compounds which is beneficial to human health and can be used as basis of folkloric remedies for diabetes.