In by Raphikammer

In Asia, Africa, and parts of Central/South America,

naturally occurring green and blue-green algae have

been harvested and consumed for their nutritive properties

for centuries.

In western cultures, for approximately

30 years, certain freshwater blue green algae (cyanobacteria)

have been accepted as a source of food, in particular

Spirulina (Arthrospira) platensis and Spirulina maxima.

Beginning in the early 1980s, another blue-green species,

Aphanizomenon flos-aquae (AFA), was adopted for similar

uses. Both are rich in proteins, vitamins, essential amino

acids, minerals, and essential fatty acids. Consumers of

blue-green algae report a wide variety of putative effects,

such as mental clarity, increased energy, blood and colon

cleansing, increased focus, particularly in children with

attention deficit disorder, improved digestion, increased

eye health, healthier joints, and tissues. In the past 10

years, owing largely to the strong anecdotal consumer testimony

about them, studies have been conducted to verify

not only their nutritional efficacy but also their potential

pharmaceutical benefits as well.


Worldwide, algae, for thousands of years, have been a

food source and treatment for various physical ailments.

In coastal regions of the Far East, recorded use of macroalgae

(sea weed) as a food source began approximately

6000 BC, with evidence that many species were used for

food and medical treatment by around AD 900. The Spanish

recorded the use of microalgae as a food source when

they reported that the natives of Lake Texcoco collected

cyanobacteria from the waters of the lake to make sundried

cakes. In present day Africa, local tribes harvest

cyanobacteria in the Lake Chad region, primarily Spirulina,

and also use it to make hard cakes, called dihe.

In some regions of Chad, people consume from 9 to

13 g/meal, constituting 10% to 60% of the meal. However,

the longest recorded use of cyanobacteria as food

is the consumption of Nostoc flagelliforme in China, where

there are records of its use for some 2000 years and where

it is still harvested on a large scale. Use of microalgae

in the western culture began in the 1970s. Most commercial

producers of microalgae are located in the Asia-

Pacific rim, where approximately 110 commercial producers

of microalgae have an annual production capacity

from 3 to 500 tons. These cultivated microalgae include

Chlorella, Spirulina, Dunaliella, Nannochloropsis, Nitzschia,

Crypthecodinium, Tetraselmis, Skeletonema, Isochrysis, and


Within the cyanobacteria, Spirulina (Arthrospira)

platensis and S. maxima have been commercially produced

as a human and animal food supplement and food coloring

for approximately 30 years. Spirulina is cultured in

constructed outdoor ponds in Africa, California, Hawaii,

Thailand, China, Taiwan, and India. World production in

1995 was approximately 2 °ø 106 kg.

The newest cyanobacterium to be used as a food

supplement is AFA, the production of which differs significantly

from Spirulina, because it is harvested from a

natural lake rather than constructed ponds. Since the early

1980s, this alga has been harvested from Upper Klamath

Lake, Oregon, and sold as a food and health food supplement.

The popularity of both Spirulina and AFA bluegreen

algae products over other seaweeds and green algae

may be attributable to the convenience of its packaging

and consumption, as well as to its highly directed marketing

to the health-conscious consumer. In 1998, the market

for AFA as a health food supplement was approximately

US $100 million with an annual production greater than

1 °ø 106 kg (dry weight) (1–18).

Chemistry and Preparation

Edible blue-green algae are nutrient dense food. The features

common to all blue-green algae include a high content

of bioavailable amino acids and minerals, such as zinc,

selenium, and magnesium. The nutrient profile is subject

to variation by habitat, harvest procedure, quality control

for contaminating species, proper processing to preserve

nutrients, and storage conditions, all of which influence

the vitamin content and antioxidant properties delivered

by the final product. However, the appeal of blue-green algae

is their raw, unprocessed nature and their abundance

of carotenoids, chlorophyll, phycocyanins, phytosterols,

glycolipids, -linolenic acid, and other bioactive components


Approximately, 40 cyanobacteria species and genera

produce potent toxins. Spirulina products have not been

associated with toxicity reports in humans, largely owing

to its being grown under cultured conditions (22). Natural

samples and cultured strains ofAFAhave been reported to

produce neurotoxins including paralytic shellfish poisons

(neosaxitoxin and saxitoxins) and anatoxin-a. Recent work

seems to indicate that a different Aphanizomenon species

is the toxin producer. A. flos-aquae has been reported to

be dominant or codominant in water blooms containing

Microcystis and Anabaena and is found in many eutrophic

water bodies. Species of Microcystis can produce a family

76 Carmichael et al.

of potent liver toxins called microcystins. Cylindrospermin

is a hepatotoxic and nephrotoxic compound produced

by several freshwater cyanobacteria, including Cylindrospermopsis

raciborskii and Anabaena spp (23). Several species

of marine and freshwater cyanobacteria (including a number

of Nostoc, Anabaena, and Microcystis species) produce

the neurotoxic amino acid BMAA (-N-methylamino-

L-alanine) (24). Although these toxic substances are probably

not naturally present in the target species discussed

below, the possibility that they might be present as contaminants

in commercial products highlights the need for

rigorous quality-control measures.

Blue-green algae products most often come in a

tablet form as algal material directly compressed. The

tablets can contain fillers such as sugars or starches called

binders, which give shape and stability to the tablets.

Algae supplements also come in a capsule form to neutralize

the taste and make the product easier to swallow,

or can be bought by the pound in powder form or in liquid

extract forms. Some companies combine the algae in

“green supplements” that contain other health-enhancing

ingredients such as alfalfa sprouts. Supplements come in

kosher or vegetarian forms, and can be combined with digestive

aids. Recommended dosages of blue-green algae

products vary widely, but can be as much as 20 g/day.

On the average, companies that produce algal products

for consumption as nutritional supplements recommend

500 mg to 1 g/day to start, with a build up over time

to several grams a day, often without an upper limit on

consumption (25,26).



Two types of blue-green algae form the major nutritional

supplement groups, Spirulina and AFA. As the traits of

each vary slightly, they are addressed separately below.


The blue-green alga Spirulina was sonamedfor its helically

coiled trichomes or rows of cells. Until recently, Spirulina

and Arthrospira were thought to belong to separate genera,

and the distinction was thought to be especially important

as only the strains of Arthrospira had been proven to be

safe for human consumption. These two are now referred

to as Arthrospira in scientific circles. Although the name

Spirulina has been persisted for commercial labeling, the

two are synonymous (27).

Spirulina is generally produced in large outdoor

ponds under controlled conditions. The safety of Spirulina

for human food has been established through long

use, and through various toxicological studies done under

the auspices of the United Nations Industrial Development

Organization (28). Spirulina is 60% to 70% protein

by weight and contains many vitamins, especially vitamin

B12 and -carotene, and minerals, especially iron and

-linolenic acid (Table 1). Recent reports suggest that a

number of therapeutic effects and pharmaceutical uses

are potential benefits of Spirulina as well (18).

Most studies of the effects of Spirulina on enhanced

body function have been performed on animals, and therapeutic

effects have been demonstrated in some cases.

Conclusive human studies are rare, but those that carry

substantive results are cited below.

Table 1 Nutritional Profile of a Commercial Spirulina Product

Composition Spirulina powder

  • Per 100 g
  • Macronutrientsa
  • Calories 382
  • Total fat 7.1 g
  • Total carbohydrate 15.5 g
  • Dietary fiber 6.8 g
  • Protein 55 g
  • Essential amino acids (mg)
  • Histidine 900
  • Isoleucine 3170
  • Leucine 5030
  • Lysine 2960
  • Methionine 1290
  • Phenylalanine 2510
  • Threonine 2770
  • Tryptophan 740
  • Valine 3500
  • Nonessential amino acids (mg)
  • Alanine 4110
  • Arginine 4130
  • Aspartic acid 5670
  • Cystine 580
  • Glutamic acid 9180
  • Glycine 2860
  • Proline 2170
  • Serine 2670
  • Tyrosine 2300
  • Vitaminsb
  • Vitamin A (as 100% -carotene) ≥200,000 IU
  • Vitamin K 548 g
  • Thiamine HCl (Vitamin B-1) 0.13 mg
  • Riboflavin (Vitamin B-2) 2.55 mg
  • Niacin (Vitamin, B-3) 14.3 mg
  • Vitamin B-6 (Pyridox.HCl) 0.77 mg
  • Vitamin B-12 93 g
  • Mineralsb
  • Calcium 446 mg
  • Iron 56 mg
  • Phosphorus 1010 mg
  • Iodine 39.1 g
  • Magnesium 305 mg
  • Zinc 1.27 mg
  • Selenium 19.6 g
  • Copper 0.32 mg
  • Manganese 3.0 mg
  • Chromium 91.7 g
  • Potassium 1620 mg
  • Sodium 815 mg
  • Phytonutrientsb
  • Phycocyanin 10 g
  • Chlorophyll 0.9 g
  • Superoxide dismutase (SOD) 531,000 IU
  • -linolenic acid (GLA) 1180 mg
  • Total carotenoids ≥370 mg
  • -Carotene ≥120 mg
  • Zeaxanthin ≥95 mg
  • Other carotenoids ∼155 mg

This is a natural product and nutrient data may vary from one lot to another.

One example of a nutrient profile for Earthrise R

Spirulina Powder, a

commercial Spirulina product, is shown in the above table.

Macronutrient data are based on most recent proximate analysis.

bThe data indicate minimum values observed over a four-year period except

for sodium where the maximum observed value is used.

Blue-Green Algae (Cyanobacteria) 77


Nutritional Rehabilitation

A multicenter study of 182 malnourished children, aged

3 months to 3 years, reported that a 5 g/day dose of Spirulina

(Arthrospira) platensis had no added benefit over 90

days when compared to traditional renutrition (29).

Four groups of undernourished children under the

age of 5 (550 total) were provided with Misola (60% millet

flour, 20% soy, 10% peanut, 9% sugar, 1% salt), Misola

plus 5 g of S. platensis, traditional meals, or traditional

meals plus 5 g of Spirulina. All diets contained about the

same number of kilocalories/day. The authors concluded

that Misola, Spirulina plus Misola, and Spirulina plus traditional

diet are all good food supplements for undernourished

children, but that Misola plus Spirulina were

superior to the other combinations (30).


In ischemic heart disease patients, Spirulina supplementation

was shown to significantly lower blood cholesterol,

triglycerides, and LDL and very-low density lipoprotein

cholesterol, and raise HDL (the so-called “good”) cholesterol.

A 4 g/day supplementation showed a higher effect

in reducing total serum cholesterol and LDL levels than

did 2 g/day (31). In a small two-month study of the effects

of 1 g/day of Spirulina (species not specified) plus

medication versus medication alone on lipid parameters

in pediatric hyperlipidemic nephritic syndrome patients,

Samuels et al. (32) reported that supplementation of medication

with Spirulina helped reduce increased lipid levels

in these patients.

Several studies in healthy populations have shown

positive effects on cardiovascular endpoints. Consumption

of Spirulina was found to reduce total lipids, free fatty

acids, and triglyceride levels in a human study involving

diabetic patients. A reduction in LDL/HDL ratio was also

observed (33). A nonplacebo-controlled open label trial

of 36 healthy adults administered 4.5 g/day of S. maxima

for six weeks reported a hypolipidemic effect, especially

on triacylglycerols and LDL = cholesterol, systolic, and

diastolic blood pressure were also reduced (34). Effects

of 8 g/day Spirulina (species not given) versus placebo

on health-related endpoints in 78 healthy elderly Koreans

were determined in a 16-week double-blinded trial.

In the verum group, significant reductions in total plasma

cholesterol and interleukin (IL)-6 concentrations were observed,

along with increases in interleukin (IL)-2 concentrations

and total antioxidant status (35). Ju´arez-Oropeza

et al. (36) reported results of investigations of the effects

of S. maxima on vascular reactivity in rats and lipid status

and blood pressure in healthy humans. The authors

suggest that the results of the rat portion of the study

indicate that Spirulina induces a tone-related increase in

endothelial synthesis/release of nitric oxide and of a vasodilating

cyclooxygenase-dependent arachadonic acid

metabolite (or a decrease in synthesis/release of an endothelial

vasoconstricting eicosanoid). In the nonplacebocontrolled

study of the effects of 4.5 g/day Spirulina on

vascular and lipid parameters in 36 human volunteers, the

authors reported reductions in blood pressure and plasma

lipid concentrations (especially triacylglycerols and LDLcholesterol).

Immune System Function

Spirulina was found to have a positive effect on the immune

system. In a paper presented at a meeting of the

Japanese Society for Immunology, volunteers consuming

a Spirulina drink for two weeks experienced enhanced

immune system function, which continued for up to six

months after the extract administration was discontinued

(37). A follow-up study reported that administration of

50 mL of a hot water extract of S. platensis augmented

interferon production and natural killer cell (NK) cytotoxicity

in more than 50% of 12 healthy human volunteers

(38). Results of a study on immunoglobulin-A in

human saliva showed a significant correlation between

the immunoglobulin-A level in saliva and the amount of

Spirulina consumed (39).

Much attention has been focused on the potential

mitigation of allergies through Spirulina intake. A group

of Russian researchers are pursuing a patent on their success

with the normalization of immunoglobulin-E in children

living in radioactive environments (40). In a more

recent study of allergic rhinitis patients, the production

of cytokines, critical in regulating immunoglobulin-E–

mediated allergy, was measured. In a randomized doubleblind

crossover study versus placebo, allergic individuals

were fed daily with either placebo or Spirulina at 1000 or

2000 mg for 12 weeks. Although Spirulina seemed to be

ineffective at modulating the secretion of Th-1 cytokines

(one type of the so-called “killer” cells), the study reported

that at 2000 mg/day, Spirulina significantly reduced IL-4

levels by 32% (41). A six-month double-blind placebo controlled

trial of the effects of 2 g/day of S. platensis on

allergic rhinitis in 150 otherwise healthy individuals aged

19 to 49 reported that the cyanobacterium treatment significantly

improved symptoms and physical findings including

nasal discharge, sneezing, nasal congestion, and

itching (42).


The sole human cancer intervention study involving

Spirulina intake was done in India on a group of tobacco

chewers afflicted with oral leukoplakia. In a study involving

44 subjects in the intervention group and 43 in

a placebo group, it was found that supplementation with

1 g of Spirulina per day for one year resulted in complete

regression of lesions in 45% of the intervention group

and in only 7% of the control group. As supplementation

with Spirulina did not result in an increase in retinal

-carotene, the authors concluded that other components

in Spirulinamaybe responsible for the regression of lesions

observed (43).

Other Endpoints

A series of four N-of-1 double-blind randomized trials

were performed on four individuals who complained of

idiopathic chronic fatigue. Each patient was his own control

and received three pairs of treatments comprising four

weeks of S. platensis and four weeks of placebo in doses

of 3 g/day. Outcome measures were severity of fatigue

measured on a 10-point scale. The score of fatigue was

not significantly different between Spirulina and placebo

(44). A small study compared the effects of S. platensis

plus a normal diet against soy protein plus normal diet

in the prevention of skeletal muscle damage in untrained

78 Carmichael et al.

student volunteers. Sixteen subjects were divided into two

equal groups (7.5 g/day S. platensis or soy protein). They

were administered the Bruce incremental treadmill exercise

prior to treatment, took the intervention for three

weeks, and were then readministered the treadmill exercise.

Results suggested that ingestion of Spirulina (but not

soy protein) protected against skeletal muscle damage and

may have led to postponement of the time to exhaustion

during all-out exercise (45).

Most of the research on Spirulina’s efficacy forhuman

nutrition and pharmaceutical use has been concerned with

the areas of vitamin and mineral enrichment, immune system

function, antioxidant effects, and anticancer and antiviral

effects. Although the number of studies referenced

by Amha Belay for his Spirulina research review article in

1993 contained 41 references, 18 his review in 2002 contained

98, 17 and this chapter has added additional information,

few of the human studies in almost any area can

be said to be conclusive. Studies are small or very small,

and most are open label nonplacebo-controlled studies. A

number of the publications do not provide adequate information

(many fail to identify the test cyanobacteria to

the species level). Interesting results in both the human

studies and in vitro and animal studies show that further

research is merited.

Adverse Effects

As previously noted, Spirulina products have not been

associated with toxicity reports in humans, probably because

commercial production is via large-scale culture

rather than wild harvest (22).

AFA (Aphanizomenon flos-aquae)

In western cultures, certain cyanobacteria have been an accepted

source of microalgal biomass for food for approximately

30 years, in particular, as discussed earlier, Spirulina

(Arthrospira) platensis and S. maxima. Beginning in the

early 1980s, another species, AFA, was adopted for similar

uses. Members of this genus are free floating (planktonic)

and occur either singly or form feathery or spindle-shaped

bundles, are cylindrical in shape, much longer than they

are wide, and contain abundant gas vesicles. They occur

in temperate climates and are most abundant in summer

and fall (46). The only known commercial harvesting of

AFA is from Upper Klamath Lake, the largest freshwater

lake system in Oregon. In 1998, the annual commercial

production of AFA was approximately 1 °ø 106 kg. As this

species is not cultured like Spirulina in outdoor ponds or

raceways, it requires very different procedures for harvesting

and processing. Other procedures, such as those for

removal of detritus and mineral materials, and those for

monitoring and reducing the amounts of certain contaminant

cyanobacteria, which can produce cyanotoxins, have

also become important in quality control and marketing

(47). The nutrient profile for AFA is very similar to that

for Spirulina (Table 2). Consumers of AFA nutritional supplements

report a variety of benefits from enhanced energy

to boosted immune system function. Cited below are

the peer-reviewed human studies extant in the literature

confirming certain of these nutritive and pharmaceutical


Nutritional Profile of a Commercial AFA Product

Nutrient Units Amount

General composition

  • Protein % 55.1
  • Carbohydrate % 29.1
  • Calories % 3.7
  • Minerals (ash) % 6.8
  • Fat calories cal/g 0.3
  • Cholesterol mg/g 0.3
  • Total dietary fiber % 5.7

Sugar profile

  • Dextrose (glucose) mg/g 19.4
  • Fructose mg/g 0.5
  • Maltose mg/g 5.6
  • Sucrose mg/g 0.8
  • Total sugars mg/g 26.2
  • Minerals and trace metals
  • Calcium mg/g 8.5
  • Chloride mg/g 2.0
  • Chromium g/g 1.2
  • Copper g/g 10.5
  • Iron mg/g 0.7
  • Magnesium mg/g 1.8
  • Manganese g/g 31.2
  • Molybdenum g/g 4.7
  • Phosphorus mg/g 4.7
  • Potassium mg/g 10.6
  • Selenium g/g 0.4
  • Sodium mg/g 2.5
  • Zinc g/g 12.1
  • Vitamins
  • Vitamin A (-carotene) IU/g 1523
  • Thiamin (B1) g/g 19.0
  • Riboflavin (B2) g/g 44.9
  • Pyridoxine (B6) g/g 14.6
  • Cobalamin (B12) g/g 3.7
  • Ascorbic acid (C) mg/g 0.4
  • Niacin mg/g 0.4
  • Folic acid g/g 0.6
  • Choline mg/g 1.3
  • Pantothenic acid g/g 3.1
  • Biotin g/g 0.2
  • Vitamin D IU/g 0.4
  • Vitamin E IU/g 0.1
  • Vitamin K g/g 47.7
  • Amino acids
  • Arginine mg/g 29
  • Histidine mg/g 9
  • Isoleucine mg/g 25
  • Leucine mg/g 43
  • Lysine mg/g 29
  • Methionine mg/g 9
  • Phenylalanine mg/g 21
  • Threonine mg/g 29
  • Tryptophan mg/g 6
  • Valine mg/g 29
  • Asparagine mg/g 49
  • Alanine mg/g 39
  • Glutamine mg/g 78
  • Cystine mg/g 3
  • Glycine mg/g 23
  • Proline mg/g 20
  • Serine mg/g 25
  • Tyrosine mg/g 16
  • Aspartic acid mg/g 46
  • Glutamic acid mg/g 49
  • Total amino acids mg/g 579
  • Blue-Green Algae (Cyanobacteria) 79
  • Table 2 Nutritional Profile of a Commercial AFA Product (Continued)
  • Nutrient Units Amount
  • Lipid analysis
  • Total lipid (fat) content 4.4% 44 mg/g
  • Total saturated fat 43% 19 mg/g
  • Total unsaturated fat 57% 25 mg/g
  • Total essential fatty acids 45% 20 mg/g
  • Total Omega-3 essential fatty acids 38% 17 mg/g
  • -Linolenic acid (ALA) 37% 16 mg/g
  • Eicosapentanoic acid (EPA) 0.4% 0.2 mg/g
  • Total Omega-6 essential fatty acids 8% 3 mg/g
  • Linoleic acid (LA) 8% 3 mg/g
  • Arachidonic acid (AA) 0.1% 0.04 mg/g

One example of a nutrient profile for Cell Tech Super Blue-Green Algae, a

commercial AFA product, as of 4-22-05, is shown in the above table.

Circulation and Immune Function

In a study examining the short-term effects of consumption

of moderate amounts (1.5 g/day) of AFA on the

immune system, it was discovered that AFA resulted

in increased blood cell counts when compared to subjects

taking a placebo. When the volunteers were grouped

into long-term AFA consumers and na¨ıve volunteers, the

na¨ıve volunteers exhibited a minor reduction in natural

killer cells, and the long-term consumers exhibited a pronounced

reduction. It was further determined that AFA

does not activate lymphocytes directly, but that it does increase

immune surveillance without directly stimulating

the immune system. The authors of this study conclude

that AFA has a mild but consistent effect on the immune

system and could function as a positive nutritional support

for preventing viral infections. They also recommend

further research intoAFA’s potential role in cancer prevention

(48). In a later report, an aqueous extract of AFAfound

to contain a novel ligand for CD62L (L-selectin). Consumption

of the extract by 12 healthy subjects in a doubleblind

randomized crossover study caused mobilization of

human CD34+CD133+ and CD34+CD133stem cells (49).

Eye Disease—Blepharospasm and Meige Syndrome

A study to determine whether blue-green algae could be

helpful in improving the eyelid spasms associated with

essential blepharospasm and Meige syndrome was undertaken

by a group of physicians. Although a few patients

exhibited a positive effect, for most patients, neither the

severity nor the frequency of facial spasms was significantly

reduced (50).


Adverse Effects

No cases of human intoxication by AFA were found in

the literature. As noted, around 40 cyanobacterial species

have been reported to produce potent natural toxins. Certain

A. flos-aquae strains were long thought to produce neurotoxins

including the paralytic shellfish poisons neosaxitoxin

and saxitoxin and anatoxin-a. A reevaluation of the

species using gene sequencing data led to the conclusion

that a different Aphanizomenon species was the actual toxin

producer (51). While it now seems clear that AFA is not

a toxin-producing species, the toxigenic Aphanizomenon

species seems to be distinguishable from AFA only by the

presence or absence of toxins and by genetic sequencing.

No evidence exists to suggest that AFA is a toxin producing

strain (51), but water blooms of AFA may also

contain Microcystis and Anabaena. Species of Microcystis

can produce a family of potent liver toxins called microcystins,

while Anabaena species can produce antitoxins and

BMAA. The microcystins, especially, are of concern, since

hepatic damage caused by this toxin is cumulative. This

has led the State of Oregon to set a safe level of microcystin

in AFA product from Klamath Lake. Currently this

level is set at 1 g/g dry weight of product, and was set

to correspond to an average daily adult intake for AFA of

2 g. Recently, the cyanobacterial toxin anatoxin-a was reported

in 3 of 39 cyanobacterial dietary supplement product

samples at concentrations of 2.5 to 33 g/g (52). Exposure

guidelines have been summarized by Burch (23). This

points to the need for rigorous quality-control measures in

production of products. These measures may range from

existing practices such as modifying the harvesting equipment

to exclude Microcystis, harvesting the water bloom

only at times when Microcystis is at a minimum, or developing

and using toxin-detecting methods in an integrated

testing scheme (47,53,54).


As a natural source of many vitamins and minerals, proteins,

and chlorophyll, it is not surprising that blue-green

algae have attracted attention among those interested in

natural sources of nutrition. Thousands of people consume

blue-green algae in its most popular forms (Spirulina

and AFA), and as a result, a large body of anecdotal material

has existed for many years concerning the positive

health benefits of blue-green algae consumption. The volume

of the testimony has contributed to a growing interest

in recent years in verifying these benefits through scientific

research. Beginning with animal and in vitro studies,

and moving toward human studies, scientists have only

recently begun to investigate some of the positive health

effects attested to by long-term consumers of blue-green

algae. These include cholesterol reduction, weight loss,

enhanced immune system function, regression of cancer related

lesions, and enhancement of blood circulation, as

well as many vitamin and mineral benefits. It must be

stated, however, that there is an overall paucity of well designed,

controlled human trials using blue-green algal

products as interventions.

As the industry relies on self-regulation, it is important

to be aware of the quality-control issues involved in

harvesting and packaging blue-green algae for consumption,

particularly in the case of AFA, which is harvested

from the wild. The World Health Organization has determined

through current knowledge of microcystin toxins

and what it calls a tolerable daily intake (TDI), an estimate

of the intake over a lifetime that does not constitute an appreciable

health risk. This TDI is derived through existing

knowledge of toxin tolerance in mice combined with principles

used in defining the health risks of other chemicals.

It carries with it a degree of uncertainty owing to the lack

of long-term data for the effect of microcystin on humans

(55). To be sure that their risk has been minimized as much

as possible, consumers of blue-green algae supplements

would be wise to check to see that the product has been

80 Carmichael et al.

tested for toxins, and it has been found to be below the

WHO/Oregon Department of Health Regulatory Level of

1 g/g of microcystin (56).


The authors would like to thank Jerry Anderson (CellTech,

Inc.) and Diana Kaylor (Wright State University) for supplying

a number of references used in this text.


1. Hoppe A. Marine algae and their products and constituents

in pharmacy. In: Hoppe HA, Levring T, Tanaka Y, eds. Marine

Algae in Pharmaceutical Science. New York: Walter de

Gruyter, 1979:25–119.

2. Richmond A. Handbook of Microalgal Mass Culture. Boca

Raton, FL: CRC Press, 1990.

3. Cannell RJP. Algal biotechnology. Appl Biochem Biotech

1990; 26:85–105.

4. Ciferri O. Spirulina, the edible microorganism. Microbiol Rev

1983; 47:551–578.

5. Farrar WV. Tecuitlatl: A glimpse of Aztec food technology.

Nature 1966; 5047:341–342.

6. Ciferri O,Tiboni O. The biochemistry and industrial potential

of Spirulina. Ann Rev Microbiol 1985; 39:503–526.

7. Abdulqader G, Barsanti L, Tredici MR. Harvests of

Arthrospira platensis from Lake Kossorom (Chad) and its

household usage among the Kanembu. J Appl Phycol 2000;


8. Delpeuch F, Joseph A, Cavelier C. Consumption as food and

nutritional composition of blue-green algae among populations

in the Kanem region of Chad. Ann Nutr Aliment 1975;


9. Gao K. Chinese studies on the edible blue-green alga, Nostoc

flagelliforme: A review. J Appl Phycol 1998; 10:37–49.

10. Becker EW, Venkataraman LV. Production and processing of

algae in pilot plant scale experiences of the Indo-German

Project. In: Shelef G, Soeder CJ, eds. Algae Biomass, Production

and Use. Amsterdam: Elsevier/North Holland Biomedical

Press, 1980:35–50.

11. Lee YK. Commercial production of microalgae in the Asia

Pacific rim. J Appl Phycol 1997; 9:403–411.

12. Belay A, Kato T, Ota Y. Spirulina (Arthrospira): Potential

application as an animal feed supplement. J Appl Phycol

1996; 8:303–311.

13. Toerien DF, Grobbelaar JU. Algal mass cultivation experiments

in South Africa. In: Shelef G, Soeder CJ, eds. Algae

Biomass, Production and Use. Amsterdam: Elsevier/North

Holland Biomedical Press, 1980:73–80.

14. Li D-M, Qi Y-Z. Spirulina industry in China: present status

and future prospects. J Appl Phycol 1997; 9:25–28.

15. Soong P. Production and development of Chlorella and Spirulina

in Taiwan. In: Shelef G, Soeder CJ, eds. Algae Biomass,

Production and Use. Amsterdam: Elsevier/North Holland

Biomedical Press, 1980:97–113.

16. Becker EW, Venkataraman LV. Production and utilization of

the blue-green alga Spirulina in India. Biomass 1984; 4:105.

17. Belay A. The potential application of Spirulina (Arthrospira)

as a nutritional supplement in health management. JANA

2002; 5(2):27–48.

18. Belay A, Yoshimichi O, Kazuyuki M, et al. Current knowledge

on potential health benefits of Spirulina. J Appl Phycol

1993; 5:235–241.

19. Jensen GS, Ginsberg MS, Drapeau C. Blue-green algae as an

immuno-enhancer and biomodulator. JANA 2001; 3(4):24–


20. Chen T, Wong Y-S, Zheng W. Purification and characterization

of selenium-containing phycocyanin from selenium enriched

Spirulina platensis. Phytochemistry 2006; 67:2424–


21. Bauersachs T, Compare J, Hopmans EC, et al. Distribution

of heterocyst glycolipids in cyanobacteria. Phytochemistry

2009; 70:2034–2039.

22. Carmichael WW. The toxins of cyanobacteria. Sci Am 1994;


23. Burch MD. Effective doses, guidelines and regulations. Adv

Exp Med Biol 2008; 619;831–853.

24. Cox PA, Banack SA, Murch SJ, et al. Diverse taxa of

cyanobacteria produce -N-methylamino-l-alanine, a neurotoxic

amino acid. Proc Natl Acad Sci U S A 2005; 102;5074–


25. Gilroy GJ, Duncan J, Kauffman KW, et al. Assessing potential

health risks from microcystin toxins in blue-green algae

supplements. Environ Health Perspect 2000; 108 (5):435–439.

26. Drapeau C. Primordial Food: Aphanizomenon flos-aquae.

U.S.A. Prescott, AZ: Unity International, 2003.

27. Vonshak A. Spirulina Platensis (Arthrospira). London:Taylor

and Francis, 1997:8–11.

28. Chamorrow-Cevalos G. Toxicological research on the alga—

Spirulina. UNIDO, UF/MEX/78/048, 1980.

29. Branger B., Cadudal JL, Delobel M, et al. Spiruline as a food

supplement in case of infant malnutrition in Burkina-Faso.

Archives de p´ediatrie 2003; 10:424–431.

30. Simpore J, Kabore F, Zongo F, et al. Nutrition rehabilitation

of undernourished children utilizing Spiruline

and Misola. Nutr J 2006; 5:3.

content/5/1/3. Accessed October 12, 2009.

31. Ramamoorthy A, Premakumari S. Effect of supplementation

of Spirulina on hypercholesterolemic patients. J Food

Sci Technol 1996; 33:124–128.

32. Samuels R, Mani UV, Iyer UM, et al. Hypocholesterolemic

effect of Spirulina in patients with hyperlipidemic nephritic

syndrome. J Med Food 2002; 5:91–96.

33. Mani S, Iyer U, Subramanian S. Studies on the effect of

Spirulina supplementation in control of diabetes mellitus.

In: Subramanian G, Kaushik BD, Venkataraman GS, eds.

Cyanobacterial Biotechnology. U.S.A. Enfield, NH: Science

Publishers, Inc., 1998:301–304.

34. Torres-Duran PV, Ferreira-Hermosillo A, Ju´arez-Oropeza

MA. Antihyperlipemic and antihypertensive effects of

Spirulina maxima in an open sample of Mexican population:

a preliminary report. Lipids Health Dis 2007;

6:33. Accessed

November 12, 2009.

35. Park HJ, Lee YJ, Ryu HK, et al. A randomized double-blind,

placebo-controlled study to establish the effects of Spirulina

in elderly Koreans. Ann Nutr Metab 2008; 52:322–328.

36. Ju´arez-Oropeza MA, Mascher D, Torres-Dur´an PV, et al. Effects

of Spirulina on vascular reactivity. J Med Food 2009;


37. Saeki Y, Matsumoto M, Hayashi A, et al. The effect of Spirulina

hot water extract to the basic immune activation. Summary

of paper presented at: The 30th Annual Meeting of the

Japanese Society for Immunology, Sendai, Japan; November

14–16, 2000.

38. Hirahashi T, Matsumoto M, Hazeki K, et al. Activation of

the human innate immune system by Spirulina: Augmentation

of interferon production and NK cytotoxicity by oral

administration of hot water extract of Spirulina platensis. Int

Immunopharmacol 2002; 2:423–434.

39. Ishii K, Katoh T, Okuwaki Y, et al. Influence of dietary Spirulina

platensis on IgA level in human saliva. J Kagawa Nutr

Univ 1999; 30:27–33.

40. Evets LB, Belookaya T, Lyalikov S, et al. Means to normalize

the levels of immunoglobulin E. Russian Federation

Blue-Green Algae (Cyanobacteria) 81

Committee of patents and trade. Patent Number (19) RU

(11) 20005486 C1 (51) 5 A 61K35/80. January 15, 1994. 1 page


41. Mao TK,Van deWater J, Gershwin ME. Effects of a Spirulinabased

dietary supplement cytokine production from allergic

rhinitis patients. J Med Food 2005; 8(3):27–30.

42. Cingi C, Conk-Dalay M, Cakli H, et al. The effects of spirulina

on allergic rhinitis. Eur Arch Otorhinolaryngol 2008;


43. Mathew B, Sankaranarayanan R, Nair P, et al. Evaluation

of chemoprevention of oral cancer with Spirulina fusiformis.

Nutr Cancer 1995; 24:197–202.

44. Baicus C, Baicus A. Spirulina did not ameliorate idiopathic

chronic fatigue in four N-of-1 randomized controlled trials.

Phytother Res 2007; 21;570–573.

45. Lu H-K, Hsieh C-C, Hsu J-J, et al. Preventive effects of Spirulina

platensis on skeletal muscle damage under exerciseinduced

oxidative stress. Eur J Appl Physiol 2006; 98:220–


46. Boone DR, Castenholz, RW. The archaea and the deeply

branching and phototropic bacteria. In: Castenholz RW, Garrity

GM, eds. Bergey’s Manual of Systematic Bacteriology.

New York: Springer-Verlag, 2001:569.

47. Carmichael WW, Drapeau C, Anderson D. Harvesting of

Aphanizomenon flos-aquae Ralfs ex Born. & Flah.var. flosaquae

(cyanobacteria) from Klamath Lake for human dietary

use. J Appl Phycol 2000; 12:585–595.

48. Jensen GS, Ginsberg DI, Huerta P, et al. Consumption of Aphanizomenon

flos-aquae has rapid effects on the circulation

and function of immune cells in humans: a novel approach to

nutritional mobilization of the immune system. JANA 2000;

2 (3):50–58.

49. Jensen GS, Hart AN, Zaske LAM, et al. Mobilization of

CD34+CD133+ and CD34+CD133stem cells in vivo by

consumption of an extract from Aphanizomenon flos-aquaerelated

to modulation of CXCR4 expression by an L-selectin

ligand? Cardiovasc Revasc Med 2007; 8:189–202.

50. Vitale S, Miller NR, Mejico LJ, et al. A randomized, placebo controlled,

crossover clinical trial of super blue green algae in

patients with essential blepharospasm or Meige syndrome.

Am J Ophthalmol 2004; 138 (1):18–32.

51. Li R, Carmichael WW, Yongding L, et al. Taxonomic reevaluation

of Aphanizomenon flos-aquae NH-5 based on

morphology and 16S rRNA gene sequences. Hydrobiologia

2000; 438:99–105.

52. Rell´an S, Osswald J, Saker M, et al. First detection of anatoxina

in human and animal dietary supplements containing

cyanobacteria. Food Chem Toxicol 2009; 47:2189–2195.

53. Chorus I, Bartram J. Toxic Cyanobacteria in Water: A Guide

to Their Public Health Consequences, Monitoring and Management.

London and New York: E&FNSpon, for theWorld

Health Organization, 1999.

54. Scott PM, Niedzwiadek B, Rawn DF, et al. Liquid chromatographic

determination of the cyanobacterial toxin beta-nmethylamino-

L-alanine in algae food supplements, freshwater

fish, and bottled water. J Food Prot 2009; 72:1769–1773.

55. Dietrich D, Hoeger S. Guidance values for microcystins in

water and cyanobacterial supplement products (blue-green

algal supplements): A reasonable or misguided approach?

Toxicol Pharmacol 2005; 203:273–289.

56. Gilroy DJ, Kauffman KW, Hall RA, et al. Assessing potential

health risks from microcystin toxins in blue-green algae

dietary supplements. Environ Health Perspect 2000; 108