Determination of Curcuminoids, Piperine, Boswellic Acids and Andrographolides in Food and Dietary Supplements by HPLC
Department of Pharmaceutical Analysis, Faculty of Pharmacy and Biochemistry, University of Zagreb, Ante Kovačića 1, Zagreb, Croatia
Received: 16 November 2021
Accepted: 5 September 2022
functional food; quality control; Box-Behnken design; curcuminoids; boswellic acids; andrographolides
Research background. As use of functional food and herbal combination products is ever increasing, methods for quality control of such preparations are necessary. Moreover, low quality of products can bring either lack of benefit or harm to the consumer. In this work, determination of three curcuminoids, piperine, six boswellic acids and three andrographolides, often used in combination products, was carried out in raw materials and dietary supplements.
Experimental approach. After extraction optimization using Box-Behnken design, it was found maximum active substance yields are obtained for 81.5 % ethanol in hydroethanolic extraction solvent, 30 min sonication time and 60 °C extraction temperature. Afterwards, a high-performance liquid chromatography method was developed and validated according to International Conference on Harmonization guidelines, with special attention being paid to selectivity, precision and robustness of the method. Lastly, 54 food and dietary supplement samples were analyzed.
Results and conclusions. It was observed most products bought locally and from credible vendors complied with relevant regulatory requirements. However, products obtained from the Internet contained little to no active substances (24 % of samples contained less than 20 % declared content), presumably showing no efficacy, or were either found to be likely adulterated or contained very high amounts of active substances, compromising safety in terms of dose-dependent adverse effects (one sample containing andrographolides) and pharmacokinetic interactions (one sample containing piperine). In conclusion, consumers should refrain from purchasing such products from the Internet and obtain them only from verified suppliers such as local pharmacies or health stores.
Novelty and scientific contribution. This work demonstrates the first developed method for analysis of aforementioned combination products which are on the rise today. The method is simple and robust and can be adapted by most laboratories for routine quality control of said products. Moreover, the work shed light on low quality of several products and signifies need for increased consumer awareness of dangers of taking such products.
Part of this work was presented at 27HSKIKI (5-8 October 2021) in Veli Lošinj, Croatia