Spirulina is an ancestral food called tecuitlatl by the Mexica. It is a cyanobacterium, i.e., a bacterium capable of photosynthesis in water, with a blue-green spiral shape. It was consumed in the form of quesillo by pre-Hispanic civilizations in regions of Mexico and was used to meet the nutritional needs of Aztec warriors and explorers.
Two different species have been distinguished in the world, Spirulina platensis and Spirulina maxima. Both are used as food supplements with similar nutritional properties and are differentiated by their place of origin. Spirulina platensis is from Lake Chad (Africa), where to this day it is used to combat malnutrition.
While Spirulina maxima is of Mexican origin, specifically from Lake Texcoco. In recent years, interest in this cyanobacterium has increased due to its nutritional value and its use as a food supplement for humans and animals at different stages of life and health status.
Spirulina in food
Currently, spirulina can be found in various products such as nutrition bars, yogurts, spaghetti, and pre-packaged beverages; however, during the food manufacturing process the nutritional properties can be modified, so in recent works, researchers have focused on ensuring its nutraceutical properties or increasing these properties through the addition of bacteria. The supplementation of various products with spirulina could represent an alternative to symbiotic formulas.
The Food and Drug Administration (FDA) has categorized spirulina as generally known as safe (GRAS), which guarantees its safety for human consumption. Similarly, the Dietary Supplement Information Expert Committee (DSI-EC) of the United States Pharmacopoeia (USP) Convention, which ensures the consumption of dietary supplements, has reported that there is no health risk associated with the consumption of spirulina.
The latter recommended its consumption for different stages of life and diseases, allowing the consumption of up to 5 grams (g) of spirulina powder in adults and up to 2 g in children. However, it is also important to consider that the use of any supplement or food supplement should be under the supervision of a specialist.
Currently, interest in spirulina cultivation around the world has increased, due to the importance of this cyanobacterium, as a result, 22 countries are producing it on a large scale. In Mexico, production has been focused on home and artisanal production, although recently in Colima, Puebla, and Veracruz production has begun on a larger scale.
Since spirulina needs nutrients for optimal growth and yield, approximately 15 percent of the total production cost is spent on nutrients, Zarrouk's culture medium is the most common. However, it also represents the biggest problem in large-scale production, along with technical difficulties and maintenance costs. Because of this, alternatives have emerged to reduce the cost of production, where through some trials the growth of spirulina is evaluated so that its nutraceutical properties are not affected and that they are low cost.
Benefits of spirulina associated with health
Currently, spirulina is used in the cosmetic, health, and food industry in humans and animals, as well as in the recovery of contaminated areas to return to their natural state. It can be found in different presentations, either in powder, capsules, or tablets.
Spirulina is considered the food of the future since it contains 96 percent of the nutrients necessary for human beings, it is a rich source of amino acids, proteins (55-70 percent in dry weight), minerals, essential fatty acids (linoleic acid, gamma-linolenic acid, and palmitic acid), vitamins and antioxidants (vitamin E and carotenoids).
It includes pigments such as phycobiliproteins and chlorophyll. Spirulina also contains polysaccharides and provides only 2.5 to 3.29 kilocalories (kcal) per gram, in addition to having 98 percent bioavailability, that is, an absorption capacity to be used by the human body.
Spirulina also contains bioactive proteins that have demonstrated activity to combat microorganisms such as viruses, bacteria, and fungi, in addition to having an anticarcinogenic effect and reducing allergies. Reports indicate that spirulina consumption prevents diarrhea and constipation by regulating digestive activity. As one can see, its consumption has been associated with some beneficial health effects.
Spirulina against diseases
Numerous clinical investigations have shown that prolonged consumption of spirulina also helps to treat diseases such as diabetes, rheumatoid arthritis, childhood malnutrition, and chronic degenerative diseases such as hypertension, atherosclerosis, and obesity with response in food absorption and appetite modulation.
Spirulina has also been used to counteract child malnutrition in countries such as Mexico and Africa, in addition to combating anemia due to its contribution of ferric iron, which is 22 times more than beef liver. It also provides calcium, which is 1.26 times more than in whole cow's milk, while the β-carotene content is up to 21 times more than that found in carrots.
In research by Joseph, Karthika, Ariya-Ajay, Akshay, and Stalin-Raj (2020), a possible antiviral action of spirulina against coronavirus has been speculated, where the presence of sulfated polysaccharides and spirulina-like substances in this cyanobacterium could bind to coronavirus glycoproteins and thus block the interaction with host cells preventing infection; however, the mechanism of action is not yet understood in detail.
Sources: Citlalli Alejandra Silos Vega and Ruth Elena Soria Guerra via UASLP, Scientific Dissemination Magazine No.261