Chemical profiling and characterization of anthraquinones from two Bulbine species and dietary supplements using liquid chromatography-high resolution mass spectrometry

Authors: AVULA, BHARATHI - University Of Mississippi; BAE, JI-YEONG - University Of Mississippi; WANG, YAN-HONG - University Of Mississippi; Wang, Mei; ALI, ZULFIQAR - University Of Mississippi; KHAN, IKHLAS - University Of Mississippi

Submitted to: Journal of AOAC International
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/16/2021
Publication Date: 5/27/2021
Citation: Avula, B., Bae, J., Wang, Y., Wang, M., Ali, Z., Khan, I.A. 2021. Chemical profiling and characterization of anthraquinones from two Bulbine species and dietary supplements using liquid chromatography-high resolution mass spectrometry. Nature Product Communications. https://doi.org/10.1093/jaoacint/qsab075.
DOI: https://doi.org/10.1093/jaoacint/qsab075

Interpretive Summary: Bulbine natalensis Baker and Bulbine frutescens (L.) Willd. are perennial herbs belonging to the family Asphodelaceae and are indigenous to South Africa. The structural characteristics of anthraquinones from methanolic extracts of dried subterranean part of Bulbine species and dietary supplements have been studied using UHPLC-QToF-MS in both negative and positive ion modes. An extensive investigation of the fragmentation pathways leading to the identification of key diagnostic fragment ions for 49 compounds. The identification of diagnostic fragment ions is important to the data mining of new compounds (those are the ones that have not yet been identified). The results showed the current method could be used to identify compounds from the methanolic extracts and to differentiate Bulbine species with high sensitivity and reproducibility.The developed analytical method would be valuable not only for herbal identification and quality control, but would also enhance understanding of the biological activity of B. natalensis in terms of safety and benefits to human health.

Technical Abstract: Bulbine natalensis Baker and Bulbine frutescens (L.) Willd. belonging to family Asphodelaceae are widely distributed in South Africa and traditionally used as aphrodisiac and skin remedy. In this current work, the structural characteristics of anthraquinone type of compounds in methanolic extracts from dried stem and roots of Bulbine species (B. natalensis and B. frutescens) and dietary supplements have been identified and analyzed using UHPLC/QToF-MS in both negative and positive ion modes. The calculated accurate masses of the protonated and deprotonated molecules, fragment ions, were used for identification of the components from two Bulbine species. A total of forty-nine anthraquinone type of compounds, including thirteen standard compounds, were identified in the crude extracts of two Bulbine species. Different diagnostic fragment ions and neutral losses were observed. The fragments produced by collision induced dissociation (CID) revealed the characteristic cleavage of glycosidic bonds, and the fragmentation pattern provided structural information about the sugars. This analytical method provided an alternative, fast method for quality assessment of Bulbine species in dietary supplements based on the anthraquinone type of compounds.