Chemometrics-assisted identification of anti-inflammatory compounds from the green alga Klebsormidium flaccidum var. zivo (KALGAE™)

Authors: QIU, SHI - University Of Mississippi; KHAN, SHABANA - University Of Mississippi; WANG, MEI - University Of Mississippi; ZHAO, JIANPING - University Of Mississippi; REN, SIYU - University Of Mississippi; KHAN, IKHLAS - University Of Mississippi; STEFFEK, AMY - Zivo Bioscience; PFUND, WILLIAM - Zivo Bioscience; LI, XING-CONG - University Of Mississippi

Submitted to: Molecules
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/17/2020
Publication Date: 2/26/2020
Citation: Qiu, S., Khan, S.I., Wang, M., Zhao, J., Ren, S., Khan, I.A., Steffek, A., Pfund, W.P., Li, X. 2020. Chemometrics-assisted identification of anti-inflammatory compounds from the green alga Klebsormidium flaccidum var. zivo (KALGAE™). Molecules. 25(5):1048. https://doi.org/10.3390/molecules25051048.
DOI: https://doi.org/10.3390/molecules25051048

Interpretive Summary: KALGAE(TM), a dried algal biomass derived from the green alga Klebsormidium flaccidum var. ZIVO, is a rich source of proteins, polysaccharides, and bioactive small molecule compounds. A chemometrics-assisted approach has been utilized to rapidly identify small molecule anti-inflammatory compounds in KALGAE(TM) with minimum isolation work. Four chemotypes of compounds including hydroxylated fatty acids, chlorophyll-derived pheophorbides, carotenoids, and glycoglycerolipids contribute to the anti-inflammatory activity of KALGAE(TM), with pheophorbide a being the most potent of the compounds identified. Our findings support previously observed in vivo anti-inflammatory effects of this algal biomass, and may facilitate product development using an optimized algal biomass with high contents of bioactive compounds. The data reported herein also demonstrate the utility of chemometrics for rapid screening and identification of bioactive natural products in general.

Technical Abstract: KALGAE(TM), a dried algal biomass derived from the green alga Klebsormidium flaccidum var. ZIVO, is a rich source of proteins, polysaccharides, and bioactive small molecule compounds. The present study was aimed at identifying small-molecule anti-inflammatory compounds present in KALGAE(TM) using an integrated approach comprising chromatographic fractionation, anti-inflammatory activity testing, UHPLC-qMS profiling, chemometric analysis, and subsequent MS-oriented isolation of active compounds. As a result, four chemotypes of compounds, including hydroxylated fatty acids, chlorophyll-derived pheophorbides, carotenoids, and glycoglycerolipids, were identified to exhibit anti-inflammatory activity. Chemometrics involving orthogonal partial least squares discriminant analysis (OPLS-DA) facilitated rapid prediction of anti-inflammatory markers. Pheophorbide a, which decreases intracellular nitric oxide production by inhibiting inducible nitric oxide synthase (iNOS), was the most potent compound identified with an IC50 value of 0.16 µg/mL in LPS-induced macrophages. It also inhibited nuclear factor kappaB (NF-kB) activation with an IC50 value of 17.0 µg/mL in PMA-induced chondrocytes. The findings of this study strongly support the anti-inflammatory potential of KALGAE(TM) as a food ingredient or dietary supplement.