Commercially cultivated Limnospira (species formerly classified to genus Arthrospira) is a popular food/supplement consumed by millions of people worldwide for health benefits. The objective of the current research was to advance the standardization technology for Limnospira. Quantitative methods were established to detect fatty acids as potential chemical markers and immune-enhancing activity. Analysis of 20 different batches of biomass obtained from one commercial grower demonstrated that there was a statistically significant relationship between the sum of two fatty acids (linoleic and γ-linolenic) and Toll-like receptor (TLR)2/TLR1-dependent activation (R2 = 0.48, p = 0.0007). Investigation of 12 biomass samples sourced from growers in 10 different countries demonstrated that fatty acid content was again significantly correlated with biological activity (R2 = 0.72, p = 0.0005) and the content of fatty acids varied by twofold and activity by 12.5-fold. This large variation between different samples confirms the need to use the present standardization methods to ensure consistent and properly characterized biomass for consumers and for future scientific research.

Department of BioMolecular Sciences School of Pharmacy The University of Mississippi University MS 38677 1848 USA

Faculty of Science University of South Bohemia Branišovská 1760 370 05 České Budějovice Czech Republic

National Center for Natural Products Research Research Institute of Pharmaceutical Sciences School of Pharmacy The University of Mississippi University MS 38677 USA

Natural Products Utilization Research Unit Agricultural Research Service United States Department of Agriculture University MS 38677 USA

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Applequist WL, Miller JS. Selection and authentication of botanical materials for the development of analytical methods. Anal. Bioanal. Chem. 2013;405:4419–4428. doi: 10.1007/s00216-012-6595-1. PubMed DOI

Shipkowski KA, et al. Naturally complex: Perspectives and challenges associated with botanical dietary supplement safety assessment. Food Chem. Toxicol. 2018;118:963–971. doi: 10.1016/j.fct.2018.04.007. PubMed DOI PMC

Landis SC, et al. A call for transparent reporting to optimize the predictive value of preclinical research. Nature. 2012;490:187–191. doi: 10.1038/nature11556. PubMed DOI PMC

Tomaselli L, Palandri RM, Tredici MR. On the correct use of the Spirulina designation. Algol. Stud. Archiv für Hydrobiol. 1996;83:539–548.

Komárek J, Lund JW. What is «Spirulina platensis» in fact? Algol. Stud. Archiv für Hydrobiologie. 1990;85:1–13.

Nowicka-Krawczyk P, Muhlsteinova R, Hauer T. Detailed characterization of the Arthrospira type species separating commercially grown taxa into the new genus Limnospira (Cyanobacteria) Sci. Rep. 2019;9:694. doi: 10.1038/s41598-018-36831-0. PubMed DOI PMC

Chacón-Lee T, González-Mariño G. Microalgae for “healthy” foods—Possibilities and challenges. Compr. Rev. Food Sci. Food Saf. 2010;9:655–675. doi: 10.1111/j.1541-4337.2010.00132.x. PubMed DOI

Ciferri O. Spirulina, the edible microorganism. Microbiol. Rev. 1983;47:551–578. doi: 10.1128/mr.47.4.551-578.1983. PubMed DOI PMC

Ahsan, M., Habib, B., Parvin, M., Huntington, T. C. & Hasan, M. R. A review on culture, production and use of spirulina as food for humans and feeds for domestic animals (2008).

Capelli B, Cysewski GR. Potential health benefits of spirulina microalgae. Nutrafoods. 2010;9:19–26. doi: 10.1007/BF03223332. DOI

Ratha SK, Renuka N, Rawat I, Bux F. Prospective options of algae-derived nutraceuticals as supplements to combat COVID-19 and human coronavirus diseases. Nutrition. 2021;83:111089. doi: 10.1016/j.nut.2020.111089. PubMed DOI PMC

Pugh ND, et al. Oral administration of a Spirulina extract enriched for Braun-type lipoproteins protects mice against influenza A (H1N1) virus infection. Phytomedicine. 2015;22:271–276. doi: 10.1016/j.phymed.2014.12.006. PubMed DOI

Food Chemicals Codex (FCC) monograph # 2181. Published by the United States Pharmacopeia (USP) and the National Formulary (NF). Accessed on June 23rd, 2020.

Nielsen CH, et al. Enhancement of natural killer cell activity in healthy subjects by Immulina(R), a Spirulina extract enriched for Braun-type lipoproteins. Planta Med. 2010;76:1802–1808. doi: 10.1055/s-0030-1250043. PubMed DOI

Meager A. Measurement of cytokines by bioassays: Theory and application. Methods. 2006;38:237–252. doi: 10.1016/j.ymeth.2005.11.005. PubMed DOI

Komárek J. Cyanoprokaryota 2—Teil/2nd part: Oscillatoriales. Susswasserflora von Mitteleuropa. 2005;19:1–759.

Gomont, M. A. Monographie des Oscillariées:(Nostacacées Homocystées). Vol. 15 (Masson, 1893).

Mühling M, Belay A, Whitton BA. Variation in fatty acid composition of Arthrospira (Spirulina) strains. J. Appl. Phycol. 2005;17:137–146. doi: 10.1007/s10811-005-7213-9. DOI

Cohen Z, Vonshak A, Richmond A. Fatty acid composition of Spirulina strains grown under various environmental conditions. Phytochemistry. 1987;26:2255–2258. doi: 10.1016/S0031-9422(00)84694-4. DOI

Xue C, et al. Molecular species composition of glycolipids from Sprirulina platensis. Food Chem. 2002;77:9–13. doi: 10.1016/S0308-8146(01)00315-6. DOI

Ljubic A, Safafar H, Holdt SL, Jacobsen C. Biomass composition of Arthrospira platensis during cultivation on industrial process water and harvesting. J. Appl. Phycol. 2018;30:943–954. doi: 10.1007/s10811-017-1332-y. DOI

Hultberg M, Lind O, Birgersson G, Asp H. Use of the effluent from biogas production for cultivation of Spirulina. Bioprocess. Biosyst. Eng. 2017;40:625–631. doi: 10.1007/s00449-016-1726-2. PubMed DOI PMC

Hena S, Znad H, Heong K, Judd S. Dairy farm wastewater treatment and lipid accumulation by Arthrospira platensis. Water Res. 2018;128:267–277. doi: 10.1016/j.watres.2017.10.057. PubMed DOI

Compositional guideline: Arthrospira platensis. https://www.tga.gov.au/compositional-guideline/arthrospira-platensis (2011).

Hantke K, Braun V. Covalent binding of lipid to protein. Diglyceride and amide-linked fatty acid at the N-terminal end of the murein-lipoprotein of the Escherichia coli outer membrane. Eur. J. Biochem. 1973;34:284–296. doi: 10.1111/j.1432-1033.1973.tb02757.x. PubMed DOI

Nguyen MT, Gotz F. Lipoproteins of gram-positive bacteria: Key players in the immune response and virulence. Microbiol. Mol. Biol. Rev. 2016;80:891–903. doi: 10.1128/MMBR.00028-16. PubMed DOI PMC

White JR, et al. Best practices in bioassay development to support registration of biopharmaceuticals. Biotechniques. 2019;67:126–137. doi: 10.2144/btn-2019-0031. PubMed DOI

Balachandran P, Pugh ND, Ma G, Pasco DS. Toll-like receptor 2-dependent activation of monocytes by Spirulina polysaccharide and its immune enhancing action in mice. Int. Immunopharmacol. 2006;6:1808–1814. doi: 10.1016/j.intimp.2006.08.001. PubMed DOI

Nakayama H, Kurokawa K, Lee BL. Lipoproteins in bacteria: Structures and biosynthetic pathways. FEBS J. 2012;279:4247–4268. doi: 10.1111/febs.12041. PubMed DOI

Pferschy-Wenzig E-M, Bauer R. The relevance of pharmacognosy in pharmacological research on herbal medicinal products. Epilepsy. Behav. 2015;52:344–362. doi: 10.1016/j.yebeh.2015.05.037. PubMed DOI

Krause E, et al. Biological and chemical standardization of a hop (Humulus lupulus) botanical dietary supplement. Biomed. Chromatogr. 2014;28:729–734. doi: 10.1002/bmc.3177. PubMed DOI PMC

Piersen CE, et al. Chemical and biological characterization and clinical evaluation of botanical dietary supplements: A phase I red clover extract as a model. Curr. Med. Chem. 2004;11:1361–1374. doi: 10.2174/0929867043365134. PubMed DOI

Taton A, Grubisic S, Brambilla E, De Wit R, Wilmotte A. Cyanobacterial diversity in natural and artificial microbial mats of Lake Fryxell (McMurdo Dry Valleys, Antarctica): A morphological and molecular approach. Appl. Environ. Microbiol. 2003;69:5157–5169. doi: 10.1128/AEM.69.9.5157-5169.2003. PubMed DOI PMC

Weisburg WG, Barns SM, Pelletier DA, Lane DJ. 16S ribosomal DNA amplification for phylogenetic study. J. Bacteriol. 1991;173:697–703. doi: 10.1128/jb.173.2.697-703.1991. PubMed DOI PMC

Muhlsteinova R, Hauer T, De Ley P, Pietrasiak N. Seeking the true Oscillatoria: A quest for a reliable phylogenetic and taxonomic reference point. Preslia. 2018;90:151–169. doi: 10.23855/preslia.2018.151. DOI

Nübel U, Garcia-Pichel F, Muyzer G. PCR primers to amplify 16S rRNA genes from cyanobacteria. Appl. Environ. Microbiol. 1997;63:3327–3332. doi: 10.1128/AEM.63.8.3327-3332.1997. PubMed DOI PMC

Cavonius LR, Carlsson N-G, Undeland I. Quantification of total fatty acids in microalgae: Comparison of extraction and transesterification methods. Anal. Bioanal. Chem. 2014;406:7313–7322. doi: 10.1007/s00216-014-8155-3. PubMed DOI PMC

Kim B, Im H, Lee JW. In situ transesterification of highly wet microalgae using hydrochloric acid. Biores. Technol. 2015;185:421–425. doi: 10.1016/j.biortech.2015.02.092. PubMed DOI

Otles S, Pire R. Fatty acid composition of Chlorella and Spirulina microalgae species. J. AOAC Int. 2001;84:1708–1714. doi: 10.1093/jaoac/84.6.1708. PubMed DOI

Tudor C, Gherasim EC, Dulf FV, Pintea A. In vitro bioaccessibility of macular xanthophylls from commercial microalgal powders of Arthrospira platensis and Chlorella pyrenoidosa. Food Sci. Nutr. 2021;9:1896–1906. doi: 10.1002/fsn3.2150. PubMed DOI PMC