Development of emulgel containing Allium Ascalonicum extract for cosmetic applications

Abstract

The current study majorly focused on anti-melanogenesis properties of Allium ascalonicum extracts (shallot) as a new active agent for cosmetic purposes. The shallot bulbs were ground and mixed with ethanol:water (60:40 v/v) to give fraction 1, the marc was further extracted with the same solvent to give fraction 2. Each fraction was separately collected and freeze-dried under a FTS system prior to hydrolysis. The lyophilized powder and its fraction were characterized using HPLC and TLC characterizations in which considered quercetin as a major compound. HPLC and TLC characterizations revealed that shallot ethanolic extract fraction 2 contained higher amount of quercetin because the solvent contained higher concentration of ethanol. The optimum condition to obtain higher concentration of quercetin is to hydrolyze shallot extracts with 0.5M HCl in 50% methanol for 75 minutes at 60 ˚C. Shallot ethanolic extracts were then evaluated for their anti-melanogenesis properties. Shallot ethanolic extract fraction 2 showed more potent in anti-tyrosinase activity with an IC50 value of 16 mg/mL. Moreover, shallot ethanolic extract fraction 2 also inhibited 25% of melanin production in B16 melanoma cells with a concentration range of 300-500 µg/mL. Both fractions were assayed for their cytotoxicities using presto blue method. The results indicated no toxicity of shallot extract to B16 melanoma cells at concentration of 6.25-500 µg/mL. The development of emulgel containing 5% shallot ethanolic extract fraction 2 was performed and evaluated for its stabilities. The emulgel passed 8 cycles of 30 minutes centrifugation at 6000 rpm with no separation. There was no color change, no separation, and no pH value change after subjected the emulgel to 6 cycles of heating-cooling cycle. The emulgel was stored at 30 ˚C, 75% RH and 40 ˚C, 75% RH for 3 months and determined the amount of quercetin. The result showed no significant change of quercetin from time zero to 3 months. Moreover, the emulgel showed no short term and long term irritation effect on 20 volunteers. Therefore, the emulgel containing Allium ascalonicum extract possesses satisfactory physical properties with good stabilities under accelerated conditions and without irritation effects.