Determination of Queercetin Content in Preparation of Powder Extract of Starfruit Leaves (Averrhoa bilimbi L.) by TLC-Densitometry

Quercetin is a flavonoid from Averrhoa bilimbi Linn. which has a variety of potential therapeutic. Therefore, this research is needed to determine the quercetin content in Averrhoa bilimbi L.’s extract powder. Method Validation is performed to ensure that an analytical method meets the criteria and requirements of a good analysis method. Method Validation used was the first category with parameters of selectivity, linearity, accuracy, and precision. The quercetin content in Averrhoa bilimbi L.’s leaf was small, requiring a parameter Limit of Detection (LOD) and Limit of Quantitation (LOQ). The analysis method was by TLC-Densitometry with Silica gel 60 F254, eluent of toluene: ethyl acetate: formic acid (7:3:1) as mobile phase with a resolution of 1.67 and 1.60 respectively. The result showed linear regression of y = 8122.4899 x + 1181.9943 (r: 0.9976; Vxo 4.88%). The accuracy was 90.2 % (w/w) ± 5.89; the coefficient of variation of precision was 1.35%; LOD and LOQ were 0.0064 µg, and 0.0215 µg respectively. The determination result showed that quercetine content in the leaf extract in ethanol of Averrhoa bilimbi L. was 0.58% (w/w) ± 0.04 and the determination quercetin from 4.0 g extract powder of Averrhoa bilimbi L. leaf showed that average content of quercetine was 6.05 ± 0.09 mg. Keywords: Quercetin, Extract Powder, Averrhoa bilimbi L, TLC-Densitometry