Simultaneous quantitative estimation of ellagic acid and gallic acid in Sudanese Solanum dubium seed by high performance thin layer chromatography (HPTLC)

Background: Solanum dubium is a plant believed to have several therapeutic effects including anti-asthmatic properties. The objective of this study was to investigate the quantitative estimation of Gallic acid and Ellagic acid from the seed extract of Sudanese Solanum dubium. Methods: A simple and rapid high-performance thin-layer chromatographic method was developed and validated for quantitative estimation of Gallic acid and Ellagic acid from the seed extract of Sudanese Solanum dubium. Results: Ellagic acid and Gallic acid were quantified by using HPTLC. The seeds were found to contain 1.1% w/w of Ellagic acid and 2.1% w/w of Gallic acid in extract. Gallic acid and Ellagic acid were chromatographed on silica gel 60 F254 TLC plate using Toluene: Ethyl acetate – Methanol – Formic acid (3:3:1:0.4 v/v/v/v) as mobile phase and quantified by densitometric scanning at 280 nm. The method was found to give compact spots for Gallic acid (Rf 0.35) and Ellagic acid (Rf 0.21). The linear regression analysis data for standard Gallic and Ellagic acids spots showed good linear relationship with r2 = 0.988 and 0.994 respectively, in the concentration range 100-3000 ng/spot, accurate (99.23-102.7%), (98.7-100.2%); precise (% RSD ≤ 2); robust (% RSD ≤ 2) and specific. The LOD and LOQ of the method were found as 653 and 396.8ng/spot and 215.5and 130 ng/spot, of Gallic acid and Ellagic acid respectively. Conclusion: The method was validated for precision, recovery and repeatability as per the International Conference on Harmonization Guidelines for Gallic acid and Ellagic acid. Statistical analysis of the data showed that the method is precise, accurate, reproducible and selective for the analysis of Gallic acid and Ellagic acid.