Phytochemical analysis and in vitro antidiabetic potential of Labu Kayu (Crescentia cujete L.) fruit extracts

Abstract

Plants have been utilized medicinally for thousands of years by societies ubiquitously throughout the world. It is stated that 80% of total world's population use plant-based remedies as their essential type of healthcare. One of the plants which consumed by the native population in Malaysia is Crescentia cujete L. or locally known as Labu Kayu for few medicinal purposes mostly as antidiabetic agent. In this study, the fruit of the Labu Kayu selected and extracted using three different solvents (hexane, 70% ethanol and water) to determine their phytochemicals and antidiabetic potential. The preliminary screening of phytochemicals of the fruit determined for total tannin content (TTC), total phenolic content (TPC), total flavonoid content (TFC), total alkaloid content (TAC) tests, and in vitro a-amylase activity was studied to determine the antidiabetic activity. The water extract of the fruit shown highest TTC (15.55 ± 0.86 mg TA/g) and TPC (3.07 ± 0.08 mg GAE/g) while, ethanol extract shown the highest TFC (17.59 ± 0.21 mg CE/g) and TAC (221.67 ± 0.88 mg AE/g). The highest inhibition of a-amylase activity was observed as 59.12 ± 0.99%, followed by 37.57 ± 0.99% and 15.47 ± 0.99% in 1.0 mg/mL and, the IC50 values were recorded as 4.00, 2.32 and 0.60 mg/mL, for hexane, 70% ethanol and water extracts, respectively. In conclusion, C. cujete fruit comprised of polar bioactive constituents majorly with a-amylase inhibitory activity to treat diabetes. Further studies are required to isolate and characterize the active constituents and determine their efficacy in in vivo and molecular models.