The Effect of Different Extraction Method and Validation of the HPLC Method for Sinensetin Quantification in Cat Whiskers (Orthosiphon aristatus Blume Miq.)

Introduction: The study investigates the quantification of sinensetin, a bioactive compound with antioxidant, anti-obesity, and anti-cancer properties, in cat's whiskers (Orthosiphon aristatus). The primary aim is to evaluate the effect of different extraction methods on sinensetin yield and to validate an HPLC method for accurate quantification. Methods: The research employed two extraction techniques: reflux and maceration. The HPLC method was validated for accuracy, precision, linearity, and specificity using a reverse-phase C18 column maintained at 25°C. The mobile phase consisted of acetonitrile (60:40) and 0.1% formic acid, with an isocratic elution. A 20 μl injection volume and a flow rate of 1 ml/min were used for analysis. Results: Validation results indicated a recovery rate of 98.37 ± 3.44% and a precision relative standard deviation (RSD) of 1.12%. The linearity correlation value was found to be 0.999. Sinensetin concentrations were quantified at 0.42 ± 0.006% for the macerated extract and 0.30 ± 0.006% for the reflux extract. Discussion: The findings demonstrate that the HPLC method is both accurate and precise for determining sinensetin levels, with maceration yielding higher concentrations than reflux. These results contribute to the understanding of extraction efficiency and the potential therapeutic applications of sinensetin. Conclusion: This study confirms that accurate quantification of sinensetin in cat's whiskers is achievable using validated HPLC methods, highlighting the importance of extraction techniques in maximising bioactive compound yields.