Elastase Inhibitory Activity, Determination of Total Polyphenol and Determination of Total Flavonoids and Pharmacognosy Study of Faloak Plant (Sterculia quadrifida R.Br) from East Nusa Tenggara-Indonesia

Introduction: Faloak (Sterculia quadrifida R. Br) is one of the typical plants of East Nusa Tenggara (NTT). Faloak contain flavonoid and polyphenol compounds, and show strong antioxidants activity which potentially correlated with its elastase inhibitory activity. Therefore, in this research, elastase inhibitory activity on various part of Faloak plant was investigated. Objective: The purpose of this research was to investigate the elastase inhibitory activity, determination of total polyphenol, determination of total flavonoids, and also pharmacognosy characterization of Faloak leaves, roots, stems and stem barks. Methods: Sample of leaves, roots, stems, and stem barks were extracted by 70% ethanol using ultrasound-assisted extraction (UAE). Phytochemical screening, microscopic identification and elastase inhibitory activity testing were performed on the leaves, roots, stems, and stem barks extract. This extract with the highest elastase inhibitory activity was then determined for its total polyphenol content and of total flavonoids content. Results: UAE method with 70% ethanol successfully extracted active compounds from leaves, stems, roots, and stem barks of Faloak. Extract of all Faloak parts contained alkaloids, flavonoids, tannins, terpenes, and glycosides. The extract of Faloak stem barks showed the strongest elastase inhibitory activity as compared to the extract from other parts, with IC₅₀ of 73.7 μg/mL. Alkaloid, flavonoid, tannin, terpene, and glycoside were detected as secondary metabolite in the extract of leaves, roots, stems and stem barks. The extract of Faloak stem barks showed the highest elastase inhibitory activity with IC50 73.7 μg/mL. The total flavonoids and total polyphenol content of Faloak stem bark extract were respectively 28.75 mg/gram and 45.25 mg/gram extract. Conclusion: The 70% ethanol extract of leaves, roots, stems, and stem barks of Faloak showed elastase inhibitory activity, and stem barks extract showed the strongest activity. Faloak stem barks extract can be considered as potential to be developed as active compound in anti-aging product, both in cosmetic and pharmaceutical dosage forms.