Abstract:
Lagerstroemia speciosa (Banaba) was studied for its bioactive phytoconstituents, α-glucosidase inhibitory and antioxidant activities. The nutritional values and elemental analysis were also conducted. Preliminary phytochemical tests have revealed that the presence of alkaloids, flavonoids, α-amino acid, carbohydrates, starch, organic acids, phenolic compounds, saponin, glycosides, reducing sugar, tannin, steroids and terpenoids in the samples. The samples had relatively high Ca, K, P and S according to EDXRF spectrum. Proximate composition has been found as 10.75 and 14.77% of moisture, 3.36 and 0.26% of crude fat, 11.24 and 2.88% of protein, 13.76 and 38.39% of dietary fiber, 51.20 and 42.48% of carbohydrate, 9.69 and 2.42% ash, and 275 and 183 kcal /100 g based on dried leaf and fruit sample. β-sitosterol, gallic acid and corosolic acid were mainly isolated from samples. In the enzymatic α-glucosidase inhibitory assay, the result suggested the order of the extracts of EtOH (leaf) > aqueous (Leaf) > EtOH (fruit) > aqueous (fruit).
In vitro antioxidant activity was also assessed by DPPH radical scavenging activity assay. IC
50 values were found to be 4.29 and 9.16 µg/mL for H
2O extracts and 2.64 and 6.17 µg/mL for 95% EtOH extracts of
L. speciosa leaf and fruit. From these results, it is suggested that these plants should be used as a remedy for the treatment of disease related to α-glucosidase inhibitory and antioxidant activities.
Phyu Phyu Myint, May Thu Soe and Htet Htet Hlaing. A study of phytoconstituents, α-glucosidase inhibitory effect and antioxidant activity of Lagerstroemia speciosa L. Leaf and Fruit. J Pharmacogn Phytochem 2017;6(4):528-533.