Evaluation of Physicochemical Properties of Beetroot-Based Dietary Supplements.

In the European Union, no specific requirements for the physicochemical parameters of dietary supplements have been established, contrary to the United States of America. This research aimed to assess the selected physical parameters of 31 commercially available beetroot-based dietary supplements in the form of tablets and capsules following the United States Pharmacopoeia (USP) guidelines and the Food and Drug Administration (FDA) recommendations. There was also estimated zinc and iron content by atomic absorption spectroscopy with flame detection. Results showed that nine products did not meet the USP requirements. Seven supplements needed more than 30 min to disintegrate. Two products in the form of tablets did not pass the friability test because of cracking. The hardness values varied significantly between manufacturers, demonstrating values from 59.1 to 455.8 N. The iron-enriched supplements differed significantly in iron content compared with the manufacturers' declaration (84.91-140.69%). Inappropriate quality of dietary supplements, which may constitute a potential risk to consumers, can be related to the lack of specific regulations in Europe; hence, similar to the USA requirements should be considered in the European Union. The work emphasizes the need to better control the quality of dietary supplements before they are introduced to the European market.

Green coffee VS dietary supplements: A comparative analysis of bioactive compounds and antioxidant activity.

The aim of this work was to assess and compare both the antioxidant potential and content of the selected biologically active substances in green coffee samples and dietary supplements based on green coffee extracts. The newly developed method using HPLC coupled with Corona detector (HPLC-CAD) allowed the analysis of chlorogenic acid, caffeine, caffeic acid, coumaric acid, and ferulic acid in a single run. The method was validated and characterized by a wide concentration range (5-75 µg/mL), sensitivity, accuracy (92.7-112%), repeatability (RSD <5.32%), and precision (1.80-4.04%). The assessment of antioxidant potential was done by the spectrophotometric Folin-Ciocalteu method. Green coffee samples and extract characterized by comparable or, in the case of some samples, even higher antioxidant properties than dietary supplements. There was found a great variety of CGA levels in dietary supplements (0.33-329 mg/g) compared to the green coffee samples (32.7 mg/g - 47.6 mg/g). The highest caffeine content (156 mg/tablet) was determined in one dietary supplement, while green coffee samples contained its lower levels (20.9 mg/g). The quality of some supplements is not satisfactory as their composition does not comply with the manufacturer's declaration. There were found discrepancies between the value determined and declared by the producer (<243%).

Mineral Composition of Dietary Supplements-Analytical and Chemometric Approach.

There is a lack of data on the actual composition and effectiveness of beetroot-based dietary supplements. The research aimed to determine the profile of 22 elements (Na, K, Ca, Mg, P, Fe, As, Se, Zn, Cu, Ag, Co, Ni, Mo, Al, Mn, Sr, Cr, Ba, Li, Pb, Cd) in beetroot and its supplements by the microwave plasma atomic emission spectrometry (MP-AES) method. The analytical procedure was optimised and validated. The composition of both groups was compared, assessing compliance with the recommended daily doses for the chosen elements, and the health risk was estimated. Furthermore, chemometric analysis was applied. Beetroots constituted a significant source of elements, especially K, Na, Mg, Ca, P, in contrast to supplements which contained their negligible amounts except from iron-enriched products which provided notable amounts of Fe (38.3-88% of the Recommended Dietary Allowance for an adult male from 19 to 75 years old). Some products were significantly contaminated with toxic elements (As, Cd). Factor and cluster analyses were helpful in the differentiation of beetroot and its supplements in view of their type (vegetable, supplement, iron-enriched supplement), origin, type of cultivation (conventional, organic), and form (capsule, tablet) based on their mineral composition. The obtained results indicate the need for more stringent control of supplements, as they may pose a significant health risk to consumers.