A validated HPLC-DAD method for simultaneous determination of major bioactive constituents of Antidiabetic herbal extracts; application to a newly Co-formulated nutraceutical product

Abstract

The global nutraceutical industry is growing each year with the introduction of new products. Ficus deltoidea Jack, Cinnamomum cassia and Nigella sativa plants are well acknowledged for their high nutritional and medicinal values worldwide, nevertheless quality control of their herbal extracts and co-formulated nutraceutical products have yet to be fully reported. In this work, a simple and cost-effective high performance liquid chromatographic method coupled with diode array detection was developed. The major biomarker constituents, namely, vitexin, cinnamaldehyde and thymoquinone were simultaneously determined without the need for preceding separation or sample clean-up processes. The liquid chromatographic separation was achieved using a Microsorb-MV C18 column (4.6 × 250 mm, 5.0 µm). Gradient elution program was performed using a mixture of solvent A (phosphate buffer, pH 4.5) and solvent B (acetonitrile), at a flow rate of 1.0 mL/min. The detection wavelength was optimized, displaying higher sensitivity of the separated peaks. Successful separation was attained within a reasonable run time ≈10 min without any interference from the matrix co-extractives. The developed method was optimized and validated as per the ICH guidelines. In addition, the identity authentication of the bioactive components was further confirmed using mass spectrometry. Clearly, the proposed and validated method provides an efficient and economic tool of improved selectivity and sensitivity for routine analysis and quality control, to ensure the safety and efficacy, of a complex matrix of nutraceutical preparation.