Boswellic Acid Composition of Frankincense Dietary Supplements and Correlation to Cytotoxic Efficacy against Treatment‐Resistant Triple Negative Breast Cancer Cells

Abstract

Frankincense is an oleogum resin from Boswellia trees of the Burseraceae family. The oleogum resin contains 15–20 % triterpenic acids, including therapeutically active boswellic acids [1]. Extracts of oleogum resins obtained from Boswellia serrata have been traditionally used in Indian folk medicine (Ayurveda) for the treatment of various chronic inflammatory diseases such as rheumatoid arthritis. Furthermore, boswellic acids are known to possess anticancer efficacy against various human cancer types, e.g. gliomas, prostate cancer, or leukemia [2–4]. The aim of the present study was to analyze the contents of boswellic acids in dietary supplements from various Boswellia species grown in different areas and to correlate the concentrations of distinct boswellic acids to the extracts' cytotoxic efficacy against chemoresistant triple‐negative human breast cancer cells. Accordingly, a new method to quantify a large variety of pentacyclic triterpenic acids was developed. Dietary supplements from various Boswellia species Boswellia serrata, Boswellia sacra, Boswellia carterii, and others were extracted with methanol and analyzed by high performance reversed‐phase liquid chromatography coupled with tandem mass spectrometric detection (HPLC‐MS/MS). Besides, the effects of the extracts against the treatment‐resistant, triple negative human breast cancer cell line MDA‐MB‐231 were investigated in vitro by using a cell viability assay. The extracts exhibited potent cytotoxic activity against the human breast cancer cell line. Correlations between the boswellic acid contents and the cytotoxic efficacy were determined by multiple linear regression and principal component regression. This approach allowed not only the correlation of complex phytochemical mixtures to desired biomedical effects, but it likewise provided evidence for key compounds governing the therapeutic efficacy. Hence, the study provides new insights into differential chemical composition patterns of frankincense dietary supplements from Boswellia species grown in different regions. Besides, the study identified distinct components correlating positively with the desired cytotoxic activity. Thus, the identified key compounds deserve further studies either as chemically pure substances or as defined chemical mixtures permitting development of the most active ingredients as potential anticancer drug candidates.Support or Funding InformationThis work was supported by the Academic Center for Complementary and Integrative Medicine (AZKIM), State Ministry of Baden‐Württemberg for Sciences, Research and Arts.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.