Klamath Lake AFA explained

Klamath Lake AFA, also called Klamath Lake Blue Green Algae and Klamath AFA (Aphanizomenon flos-aquae MDT14a), is a unique subspecies of Aphanizomenon flos-aquae. Small amounts of this cyanobacteria can be found in bodies of water worldwide,[1] but it is notable for growing prolifically in Upper Klamath Lake, Oregon.

Recently genetically reclassified as a subspecies of Aphanizomenon flos-aquae, Klamath AFA is a blue-green algae that has been harvested wild from Upper Klamath Lake since the 19080s and imported as a dietary supplement by many countries. New advancements in genome sequencing have distinguished and named this isolate as Aphanizomenon flos-aquae MDT14a,[2] [3] distinct from other varieties of Aphanizomenon flos-aquae, prompting a reexamination of past studies, nomenclature and taxonomy classification.

Aphanizomenon flos-aquae was historically treated as a single homogeneous species, but modern genetic technology reveal significant diversity within the group, with at least 18 separate genomes[4] identified and potentially over 100 awaiting classification.[5] These findings underscore the need to differentiate between toxic and non-toxic varieties within both the genus and species.

Multiple studies have ruled out Klamath Lake Aphanizomenon flos-aquae subspecies MDT14a and LD13 as capable of producing cylindrospermopsin, microcystin, anatoxin-a, saxitoxin,[6] [7] [8] and other cyanotoxins often associated with harmful algae blooms.

Taxonomy and Distinctions Between Toxic and Non-toxic Strains

The classification of Aphanizomenon flos-aquae has undergone significant taxonomic revision in light of recent genetic studies. Genome sequencing has revealed substantial genetic variability, leading to the identification of distinct subspecies found around the world, such as strains like AFA FACHB-1287[9] , AFA FACHB-1265[10] , AFA NRERC-008[11] , isolates like AFA KM1D3_PB,[12] AFA UKL13-PB,[13] and others.[14]

These advancements have clarified a longstanding misconception regarding toxin production in AFA samples from Upper Klamath Lake. Earlier studies attributed the presence of cyanotoxins such as microcystin and cylindrospermopsin directly to endogenous production by AFA. However, modern research employing precise genetic sequencing and species-specific analysis has revealed that these toxins were not capable of being produced by Klamath AFA itself but were instead the result of cross-contamination from co-occurring toxin-producing cyanobacteria inhabiting the same environment. This misattribution has significant implications, as it reinforces the necessity for accurate species-level identification in environmental and toxicological studies to prevent erroneous conclusions and ensure the integrity of public health assessments.

Morphology

Klamath AFA is a single-cell filamentous cyanobacterium characterized by the formation of trichomes—elongated chains of cylindrical vegetative cells. These trichomes aggregate into visibly separate fascicles which can reach lengths of up to 2 centimeters.[15] [16]

Within each trichome, specialized cells, known as heterocysts, help with nitrogen fixation, and are responsible for converting atmospheric nitrogen into a form usable by the organism. This process is vital for survival in nitrogen-depleted environments.

Aphanizomenon flos-aquae MDT14a also produce akinetes—dormant, thick-walled cells that form under adverse conditions. These allow the algae to withstand harsh environmental factors, such as winter temperatures or nutrient scarcity, by remaining viable on the lake's bottom sediment layer until conditions improve.

Habitat and Distribution

Upper Klamath Lake (also called Klamath Lake) in the Cascade Range of south-central Oregon hosts the only viable and harvestable population of Aphanizomenon flos-aquae MDT14a in the world[17] .[18] While this subspecies has been detected in other water bodies[19], these populations are either too sparse or are mixed with other aquatic species, making harvesting impractical.

Klamath Lake's high levels of dissolved minerals, large surface area, shallow depths, and other nutritional and environmental factors create ideal conditions for the proliferation of Aphanizomenon flos-aquae MDT14a. Some of these factors are the lake's high 4,100 feet (1,259 m) elevation,[20] eutrophic nutrient levels,[21] high alkalinity (8.5 pH or higher),[22] a large surface area of 96 square miles with an average depth of 8 feet,[23] and large number of sunny days (130[24] to 300[25])throughout the year.

Hydrology and Growing Medium

Upper Klamath Lake is fed from the north by a large watershed that is 3,768 square miles (9,760 km2) in size. Much of this water comes from the deep aquifers south of Crater Lake, traveling through the mineral-rich volcanic substrates that seep up through the ground in the form of hundreds of visible springs at the headwaters of multiple streams and tributaries that become larger Williamson and Wood River.

On average, around 4,100 cubic feet of new water flows into Upper Klamath Lake every second,[26] equivalent to 14 million cubic feet every hour, or two cubic miles of new water every month. Much of this water flows first through the Upper Klamath National Wildlife Refuge, a 46,900 acres of freshwater marshes established along the northern edge of the lake. Marsh plants break down minerals, including nitrogen, phosphorus, and sulfur, through a process called denitrification. This entire growing medium complex creates the rare and ideal conditions for the proliferation of Aphanizomenon flos-aquae MDT14a.

Research on Nutritional and Therapeutic Properties

Numerous studies have investigated the potential health benefits of Klamath AFA, including:

Controversies

Klamath AFA has been proven to be incapable of endogenously producing microcystins or other toxins. However, Aphanizomenon flos-aquae species typically cohabit with other cyanobacteria, most commonly with the Microcystis species.[31] Therefore, farmers and manufacturers of Klamath AFA must be skilled and follow the guidelines presented by the FDA[32] for harvesting and manufacturing in order to prevent cross-contamination from other lake species.

Cross-contamination of products containing Klamath AFA have occurred in the past. From 2018-2020, the FDA did three product recalls, all by the same original harvesting company.[33] [34] [35] Each of the recalls were found to have higher levels of microcystin than suggested by the WHO and EFA provisional guidelines,[36] which is less 0.00001 part per gram (one part per million or 1µ/gram). These investigations led to Class 2 voluntary recalls of the affected products. The products were all linked to several batches of AFA harvested by the company between 2015 and 2017.

FDA-Guided Industry Practices for Harvesting AFA

From these recalls, the FDA started working with harvesting companies, all with 20 or more years of experience, to outline new industry practices and testing procedures for harvesting AFA.[32] These now include:

  1. At the time of harvest, examining AFA at the harvesting site for contaminating cyanobacteria.
  2. At the time of harvest, testing the water and AFA for microcystins.
  3. After harvest, testing the AFA slurry for microcystins.
  4. Before selling AFA products, testing each lot or batch for microcystins.
  5. Using more than one test method to confirm results.
  6. Using a test method that can detect multiple variant forms of microcystins.
  7. Using certified testing laboratories and validated methods.
  8. Providing a certificate of analysis to purchasers for each lot or batch sold.

Since these stringent guidelines were developed, no product recalls have occurred. The FDA now states[37] on their site that properly harvested blue-green algae from Klamath Lake is safe to eat and is used in dietary supplements and food products around the world.

Algae as nutraceuticals

Algae, encompassing a vast and diverse group of species[38], are emerging as sources for nutrition[39] and sustainable food possibilities.[40] These ancient organisms, which range from microscopic phytoplankton to macroscopic seaweeds, show potential as nutrient-dense food sources, having high concentrations of proteins, essential fatty acids, vitamins, chlorophyll, phycocyanin, and other bioactive compounds. Their ability to grow in saline and fresh water, coupled with their capacity for rapid biomass production, position algae for advancing nutritional innovation.

Similar to the burgeoning field of fungi and mushroom sciences that are redefining nutraceuticals with their immunomodulatory[41] [42] [43] and neuroregenerative properties, learning to distinguish between toxic and nontoxic varieties of algae is a key to unlocking their full potential as safe and effective sources of nutrition, medicine, and sustainable food. Advancements in genomic differentiation now allow for a more accurate understanding of its diverse strains, ensuring that future research, public health guidelines, and nutritional applications are based on precise and reliable science.

See also

Notes and References

  1. Scoglio . Gabriel D. . Jackson . Harry O. . Purton . Saul . 2024-08-01 . The commercial potential of Aphanizomenon flos-aquae, a nitrogen-fixing edible cyanobacterium . Journal of Applied Phycology . en . 36 . 4 . 1593–1617 . 10.1007/s10811-024-03214-0 . 2024JAPco..36.1593S . 1573-5176 . "122 different AFA strains have been reported based on morphological and phylogenetic analyses, and have been isolated from sites around the world... North America, Asia, and all across Europe, from Portugal and Spain to the Baltic Sea and Scandinavia.".
  2. Web site: Driscoll . Connor B. . Comparative Genomics of Freshwater Bloom-Forming Cyanobacteria and Associated Organisms . 2024-12-02 . ir.library.oregonstate.edu.
  3. Web site: Underwood . Jennifer C . Hall . Natalie C . Mumford . Adam C . Harvey . Ronald W . 2024-05-01 . Relation between the relative abundance and collapse of Aphanizomenon flos-aquae and microbial antagonism in Upper Klamath Lake, Oregon . academic.oup.com.
  4. Web site: Genome. NCBI.
  5. Web site: Taxonomy browser (Aphanizomenon flos-aquae). www.ncbi.nlm.nih.gov.
  6. Burdick . S. M. . Effects of harmful algal blooms and associated water-quality on endangered Lost River and shortnose suckers . Harmful Algae . July 2020 . 97 . 101847 . 10.1016/j.hal.2020.101847. 32732045 . 2020HAlga..9701847B .
  7. Driscoll . C.B. . Meyer . K.A. . Sulcius . S. . Brown . N.M. . Dick . G.J. . Cao . H. . Gasiunas . G. . Timinskas . A. . Yin . Y. . Landy . Z.C. . Otten . T.G. . Davis . T.W. . Watson . S.B. . Dreher . T.W. . 2018 . A closely-related clade of globally distributed bloom-forming cyano-bacteria within the Nostocales . Harmful Algae . 77 . 93–107 . 10.1016/j.hal.2018.05.009 . 30005805 . 2018HAlga..77...93D . Elsevier.
  8. Carmichael . W.W. . Drapeau . C. . Anderson . D.M. . 2000-12-01 . Harvesting of Aphanizomenon flos-aquae Ralfs ex Born. & Flah. var. os-aquae (Cyanobacteria) from Klamath Lake for human dietary use. . Journal of Applied Phycology . 12 . 6 . 585–595 . 10.1023/A:1026506713560 . 2000JAPco..12..585C . Springer Nature.
  9. Web site: Aphanizomenon flos-aquae FACHB-1287 . 2024-12-02 . NCBI . en.
  10. Web site: Aphanizomenon flos-aquae FACHB-1265 . 2024-12-02 . NCBI . en.
  11. Web site: Aphanizomenon flos-aquae NRERC-008 . 2024-12-02 . NCBI . en.
  12. Web site: Aphanizomenon flos-aquae KM1D3_PB . 2024-12-02 . NCBI . en.
  13. Web site: Aphanizomenon flos-aquae UKL13-PB . 2024-12-02 . NCBI . en.
  14. Web site: NCBI Complete Taxonomic List of 130+ Aphanizomenon flos-aquae Varieties . NCBI Taxonomy Browser.
  15. Li . Renhui . Carmichael . Wayne . Liu . Yongding . Watanabe . Makoto M. . 2020-11-01 . Taxonomic re-evaluation of Aphanizomenon flos-aquae NH-5 based on morphology and 16S rRNA gene sequences . Hydrobiologia . 438 . 1 . 99–105 . 10.1023/A:1004166029866 . Research Gate.
  16. Scoglio . Gabriel D. . Jackson . Harry O. . Purton . Saul . 2024-08-01 . The commercial potential of Aphanizomenon flos-aquae, a nitrogen-fixing edible cyanobacterium . Journal of Applied Phycology . en . 36 . 4 . 1593–1617 . 10.1007/s10811-024-03214-0 . 2024JAPco..36.1593S . 1573-5176.
  17. Scoglio . Gabriel D. . Jackson . Harry O. . Purton . Saul . 2024-08-01 . The commercial potential of Aphanizomenon flos-aquae, a nitrogen-fixing edible cyanobacterium . Journal of Applied Phycology . en . 36 . 4 . 1593–1617 . 10.1007/s10811-024-03214-0 . 2024JAPco..36.1593S . 1573-5176 . The AFA biomass used for commercial products is exclusively harvested from the wild; specifically from Klamath Lake in Oregon, USA..
  18. Scoglio . Gabriel D. . Jackson . Harry O. . Purton . Saul . 2024-08-01 . The commercial potential of Aphanizomenon flos-aquae, a nitrogen-fixing edible cyanobacterium . Journal of Applied Phycology . en . 36 . 4 . 1593–1617 . 10.1007/s10811-024-03214-0 . 2024JAPco..36.1593S . 1573-5176.
  19. Aavad . Jacobsen Bodil . 1994-09-01 . Bloom formation of Gloeotrichia echinulata and Aphanizomenon flos-aquae in a shallow, eutrophic, Danish lake . Hydrobiologia . en . 289 . 1 . 193–197 . 10.1007/BF00007420 . 1573-5117.
  20. Web site: Upper Klamath Lake: The Largest Lake in Oregon . Elevation: 1259 meters.
  21. Web site: November 2006 . Causes and Effects of Nutrient Conditions in the Upper Klamath River . PacifiCorp . "The extreme abundance of chlorophyll, and the growth of phytoplankton are a natural consequence of the occurrence of excess nutrients...".
  22. Web site: 2023-01-01 . Water and Endangered Fish in the Klamath River Basin . 2016-12-20 . Oregon Water Science Center . "High pH values observed in Upper Klamath Lake have been associated with algal photosynthesis during the rapid early growth phase of the A. flos-aquae blooms...often greater than 9.5.".
  23. Web site: Upper Klamath Lake: The Largest Lake In Oregon . Lakepedia . Average depth: 2.3 meters (7.59 feet).
  24. Web site: City. myperfectweather.com.
  25. Web site: History of Klamath Falls | Klamath Falls, OR .
  26. Web site: 2024-11-25 . Upper Klamath Lake Near Klamath Falls, OR - 11507000 . United States Geological Survey . According to current data, approximately 4,139.7 cubic feet per second (cfs) of water is flowing into Upper Klamath Lake today, primarily sourced from the Williamson River and other tributaries in the area..
  27. Merino . José Joaquín . Cabaña-Muñoz . María Eugenia . Pelaz . María Jesús . 2020 . The Bluegreen Algae (AFA) Consumption over 48 h Increases the Total Number of Peripheral CD34+ Cells in Healthy Patients: Effect of Short-Term and Long-Term Nutritional Supplementation (Curcumin/AFA) on CD34+ Levels (Blood) . Journal of Personalized Medicine . en . 10 . 2 . 49 . 10.3390/jpm10020049 . free . 2075-4426.
  28. Web site: Aphanizomenon Flos-Aquae - an overview ScienceDirect Topics . 2024-12-03 . www.sciencedirect.com.
  29. Hart . Aaron N. . Zaske . Lue Ann . Patterson . Kelly M. . Drapeau . Christian . Jensen . Gitte S. . 2007-09-22 . Natural Killer Cell Activation and Modulation of Chemokine Receptor Profile In Vitro by an Extract from the Cyanophyta Aphanizomenon flos-aquae . Journal of Medicinal Food . 10 . 3 . 435–441 . 10.1089/jmf.2007.401 . 17887936 . 1096-620X.
  30. Web site: Canada . Library and Archives . 2022-09-01 . Item – Theses Canada . 2024-12-03 . library-archives.canada.ca.
  31. Scoglio . Gabriel D. . Jackson . Harry O. . Purton . Saul . 2024-08-01 . The commercial potential of Aphanizomenon flos-aquae, a nitrogen-fixing edible cyanobacterium . Journal of Applied Phycology . en . 36 . 4 . 1593–1617 . 10.1007/s10811-024-03214-0 . 2024JAPco..36.1593S . 1573-5176 . "Aphanizomenon flos-aquae typically cohabits with other cyanobacteria, most commonly Microcystis species: mainly M. aeruginosa, Dolichospermum/Anabaena flos-aquae and Gloeotrichia echinulata.".
  32. Program . Human Foods . 2024-09-09 . Blue-Green Algae Products and Microcystins . FDA . en.
  33. Web site: 2020-12-10 . Beverage with AFA Product Recall . FDA.
  34. Web site: 2018-08-07 . AFA Supplement Capsules Recalled . FDA.
  35. Web site: 2018-07-27 . AFA Capsules Supplement, Product Recall . FDA.
  36. Schaeffer . David J. . Malpas . Phyllis B. . Barton . Larry L. . 1999-09-01 . Risk Assessment of Microcystin in Dietary Aphanizomenon flos-aquae . Ecotoxicology and Environmental Safety . 44 . 1 . 73–80 . 10.1006/eesa.1999.1816 . 10499991 . 1999EcoES..44...73S . 0147-6513.
  37. Web site: 2024-09-26 . US Food & Drug Natural Toxins in Food . USDA FDA.
  38. Guiry . Michael D. . 2012-10-02 . How Many Species of Algae Are There? . Journal of Phycology . 48 . 5 . 1057–1063 . 10.1111/j.1529-8817.2012.01222.x . 0022-3646 . 27011267 . 2012JPcgy..48.1057G . Algae have been estimated to include anything from 30,000 to more than 1 million species. . PubMed.
  39. Piwowar . Arkadiusz . Harasym . Joanna . 2020 . The Importance and Prospects of the Use of Algae in Agribusiness . Sustainability . en . 12 . 14 . 5669 . 10.3390/su12145669 . free . 2071-1050.
  40. Ullmann . Jörg . Grimm . Daniel . 2021-06-01 . Algae and their potential for a future bioeconomy, landless food production, and the socio-economic impact of an algae industry . Organic Agriculture . en . 11 . 2 . 261–267 . 10.1007/s13165-020-00337-9 . 2021OrgAg..11..261U . 1879-4246.
  41. Zhao . Shuang . Gao . Qi . Rong . Chengbo . Wang . Shouxian . Zhao . Zhekun . Liu . Yu . Xu . Jianping . 2020-12-05 . Immunomodulatory Effects of Edible and Medicinal Mushrooms and Their Bioactive Immunoregulatory Products . Journal of Fungi . en . 6 . 4 . 269 . 10.3390/jof6040269 . free . 2309-608X.
  42. Martel . Jan . Ko . Yun-Fei . Ojcius . David M. . Lu . Chia-Chen . Chang . Chih-Jung . Lin . Chuan-Sheng . Lai . Hsin-Chih . Young . John D. . 2017-11-01 . Immunomodulatory Properties of Plants and Mushrooms . Trends in Pharmacological Sciences . English . 38 . 11 . 967–981 . 10.1016/j.tips.2017.07.006 . 0165-6147 . 28863984.
  43. Pathak . Manash Pratim . Pathak . Kalyani . Saikia . Riya . Gogoi . Urvashee . Ahmad . Mohammad Zaki . Patowary . Pompy . Das . Aparoop . 2022-05-01 . Immunomodulatory effect of mushrooms and their bioactive compounds in cancer: A comprehensive review . Biomedicine & Pharmacotherapy . 149 . 112901 . 10.1016/j.biopha.2022.112901 . 36068771 . 0753-3322.

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