HPLC Quantitative Analysis of Stingless Bee Propolis Extracts

Abstract

Propolis has been relied on many therapeutic purposes such as treatment of cold, cancer and inflammation. The biological activities and chemical constituents of each type of propolis mainly depend on geographical regions and on the bee species. Although, stingless bee propolis has been reported to possess various medicinal properties, the study in HPLC quantitative analysis is limited. In present study, HPLC was performed using a Hypersil BDS Cu-column eluted with gradient methanol: 0.2% formic acid with a flow rate of 1 mL/min at 25 ºC. The DAD detector was monitored at wavelength 245 nm and the injection volumes for all samples and standard were 5 µL. the method was illustrated to be precise with RSD less than 1% and 2.5% for intraday and interday, respectively. The average recoveries of alpha mangostin, the standard compound, were 98.81, 99.00 and 101.25% for low, medium and high level of alpha mangostin. Limit of detection (LOD) at a signal to noise ratio (s/n) of 3:1 was found to be less than 0.067 µg/mL while Limit of quantitation (LOQ) at a s/n of 10:1 was found to be less than 0.2 µg/mL. From the validated parameters; precision, accuracy, LOD and LOQ, the proposed HPLC method was successfully performed to quantitatively analyze the major component, alpha mangostin, in stingless bee propolis extracts according to International Conference on Harmonization (ICH) guidelines. This work would be useful as a guide for the standardization of stingless bee propolis raw materials and their commercial products.