Phytochemical and bioactivity analysis of stem bark,flower, and leaf extracts of talok (muntingiacalabura l.)

Muntingia calabura L. is a plant which is known to be rich in bioactive compounds such as flavonoids groups of flavones and flavanones. In Indonesia, it is locally known as “Talok” and is a common ornamental and roadside plant which has not been exploited for commercial use. The present research describes the phytochemical analysis of the stem bark, flower, and leaf extracts of Muntingia calabura L. using three different solvents and two different methods of extraction. The analysis included the qualitative phytochemical screening test, determination of total phenolic content by Folin-Ciocalteau assay, identification of volatile compounds by Gas Chromatography – Mass Spectrometry (GC-MS) analysis, free radical scavenging activity by 1.1-diphenyl-2-picrylhydrazyl (DPPH) assay, and antidiabetic activity by alpha-glucosidase inhibition assay. All extracts revealed the presence of bioactive compounds. Bark methanolic extract using maceration method revealed the presence of high phenolic content (258.72±3.04 mg GAE/g) and strong free radical scavenging activity (IC50 value: 23.00±1.21 mg/L). All of the methanol and acetone extracts showed high phenolic content and antioxidant activity while the hexane extracts showed very low phenolic content and antioxidant activity. All of the extracts showed moderate correlation (R2: 0.7228) between their total phenolic content and IC50 values of antioxidant activity. The bark methanolic extract using microwave assisted extraction method revealed the IC50 alpha-glucosidase inhibition activity to be 157.30±13.37 mg/L. Negative correlation was observed between the alpha-glucosidase inhibition and the total phenolic content and antioxidant activity. The most prominent volatile compound detected in the three extracts having the highest phenolic content was 1,2,3- Benzenetriol (Pyrogallic acid).