Potency of moringa (Moringa oleifera L.) leaves extract containing quercetin as a depigmentation agent inhibiting the tyrosinase enzyme using in-silico and in-vitro assay

Hyperpigmentation is a disorder of facial skin pigments due to an increase in the process of melanogenesis, which can cause a darkening of skin color. A flavonoid compound with potential as a skin-lightening agent is quercetin, commonly found in Moringa oleifera L. leaves. This study aims to determine quercetin's affinity and molecular mechanism on tyrosinase enzyme target proteins using an in-silico molecular docking method. Docking of quercetin with the tyrosinase enzyme produced a bond energy value of -7.08 kcal/mol. In comparison, the tropolone as a native ligand with the tyrosinase enzyme produced -4.79 kcal/mol. Quercetin has a strong affinity for the tyrosinase enzyme, indicated by the bond energy results from docking. Quercetin extraction from Moringa oleifera L. leaves using three different extraction methods: maceration, soxhlation, and reflux were made. The chromatogram from the TLC-Densitometry method showed the identification result in maceration and soxhlation extract containing quercetin, while reflux extract did not contain quercetin. The highest quercetin was obtained in the maceration method with a level of 21.57% w/w, while the soxhlation received quercetin as much as 18.49% w/w. In-vitro tests were carried out using a spectrophotometric method using a comparison of kojic acid. The in-vitro test found that IC₅₀ from kojic acid was 48.90 µg/mL and IC₅₀ of the extract from moringa leaf maceration of 115.36 µg/mL. Based on this research, quercetin compounds in Moringa oleifera L. leaves from maceration can potentially be skin-lightening agents.