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| Date: 11-15-2016 | HC# 051662-556 |
Meins J, Artaria C, Riva A, Morazzoni P, Schubert-Zsilavecz, Abdel-Tawab M. Survey on the quality of the top-selling European and American botanical dietary supplements containing boswellic acids. Planta Med. April 2016;82(6):573-579. doi: 10.1055/s-0042-103497.
The oleo-gum-resin of boswellia (Boswellia serrata, Burseraceae) is a treasured commodity historically referred to as frankincense and used in Ayurvedic medicine to treat inflammatory conditions. Since the 1980s, sales of boswellia products have continued to increase in accordance with the mounting scientific evidence of the anti-inflammatory effects of B. serrata resin. However, commercially available boswellia consists not only of resin from B. serrata (a tree native to India) but also of resin from the trees B. carteri and B. frereana (native to Africa), and B. sacra (native to southern Arabia). Experimental evidence indicates that boswellic acids (BAs) are the most important anti-inflammatory constituents of B. serrata resin. The BAs characteristic of B. serrata are also found in B. carteri and B. sacra but in different proportions, while resin from B. frereana does not contain appreciable amounts of the characteristic BAs. In this study, the BA content of the top-selling boswellia products in the United States (US) and Europe was analyzed and the results were compared to the information on product labels.
To select the most relevant products, the authors purchased boswellia market data (sales over the previous 52 weeks, ending in December 2014) from the market research firms SPINS (Chicago, Illinois) (data for the US natural product retail channel) and IMS OTC (Danbury, Connecticut) (data for European over-the-counter [OTC] sales). Based on this data, 17 boswellia products were selected for the study; six of the best-selling products in the US, representing 70% of the US market value, and 11 products representing 40% of the market value in Europe. The products were purchased in stores, pharmacies, and online, and included several preparation forms (tablets, capsules, and sachets). Vouchers were deposited at the Central Laboratory of German Pharmacists; Eschborn, Germany.
For analysis, the contents of ten tablets, capsules, or sachets were ground, mixed, and extracted with methanol. Liquid chromatography-mass spectrometry (LC-MS) was used to quantify the BA contents. The six most abundant BAs found in B. serrata resin (α-BA, β-BA, 11-keto-BA, acetyl-α-BA, acetyl-β-BA, and acetyl-11-keto-BA [AKBA]) were analyzed. The fitness of the applied LC-MS method was assessed by judging linearity, accuracy, and precision. From the data presented, the authors conclude, "Both the high accuracy reflected in the high recovery rates as well as the good precision at each concentration level for each BA in different matrices verify the ruggedness of the applied method … ."
Of the 17 products analyzed, 14 were labeled as containing other ingredients along with boswellia extracts. The other three products were labelled as containing boswellia extracts only. Only five of the products had labels that identified the species of boswellia, as well as the part of the plant used, and the amount of BAs in the product. Although all of the products except one claimed to contain B. serrata, two products did not declare the part of the plant used nor the BA content; eight products did not make a claim on BA content but did state the plant part used; and one did not declare the part of the plant used but did declare the BA content. Characterizations of the boswellia extract varied widely on the product labels, including 65% organic acids, 85% total acids, 60% BAs, 65% BAs, 70 mg total BAs, 30% AKBA, 10 mg AKBA, 70% BAs min. 20% acetyl-β-BA, and "titrated alpha keto bowellic acid [sic]."
One product from Italy did not contain any of the six characteristic BAs. One US product contained only minor traces of BAs, suggesting the absence of any substantive B. serrata content or the use of B. frereana. Another product that carried all of the basic label information (species, plant part, and BA content) was found to have a ratio of non-acetylated BAs to acetylated BAs of < 1, indicating the presence of B. carteri or B. sacra. Two other samples were found to have BA contents that did not conform to the amount stated on the product label; one contained roughly one half of the amount of acetyl-β-BA claimed and one product contained almost two-fold more AKBA. Two product labels did not declare the use of an extract enriched in AKBA up to 66%.
Misleading claims and product information may give consumers a false sense of quality of a product. Consumers may erroneously correlate higher total acids contents with increased efficacy. It is noted that the discrepancies between BA content and label claims observed in this study are not necessarily evidence of adulteration; they may be due to the use of different analytical methods or inconsistent quality control. The authors state, "It may be generally assumed that the declaration on the label is based on HPLC [high-performance liquid chromatography] analysis, including more BAs than the six major BAs determined by the LC/MS method in this survey, leading, in consequence, to higher BA contents."
In summary, the BA contents that were determined in this study did not support the information provided on the labels of seven of the 17 products analyzed. The authors conclude that the problem of mislabeling still exists and needs to be addressed by manufacturers, so that consumers can have greater confidence in the quality of boswellia products. Products should be subjected to rigorous, validated phytochemical analyses to ensure accurate label claims for botanical identity and BA contents.
At the time of the study, three of the authors were employees of Indena S.p.A. (Milan, Italy). This company manufactures Casperome®, a proprietary B. serrata resin extract, which was evaluated in the study.
—Amy C. Keller, PhD
