Beneficial effects of plant-based proteins and amino acids


Chlorella pyrenoidosa is a type of unicellular green algae. Due to its outstanding content of amino acids, proteins, fibers, antioxidant and bioactive substances, it is a popular food across the world. Chlorella has multiple properties, so much so that, as food, it is interesting from both the nutritional and therapeutic viewpoint.

Protein and amino acids content

Chlorella is broadly used as a nutritional supplement for its high protein content, besides being a good source of vitamins and mineral: it contains approximately 60% of proteins, 20% of carbohydrates and 11% of unsaturated fats [1].
Chlorella contains many essential and non-essential amino acids: it is high in alanine, arginine, leucine, serine and glutamic acid [2].

A source of vitamins and minerals

Chlorella contains vitamin C, provitamin A (β-carotene), thiamine (B1), riboflavin (B2), pyridoxine (B6), niacin, pantothenic acid, folic acid, vitamin B12, biotin, choline, vitamin K, lipoic acid and inositol, besides minerals such as phosphorous, calcium, zinc, iodine, magnesium and iron [1].
Studies prove that algal vitamin B12 is a bio-disposable source for mammals [3,4,5]. Furthermore, a study carried out on different types of algae and higher plants in order to verify their content of B-group vitamins (thiamine, riboflavin, nicotinic acid and folic acid), ascorbic acid and carotene has proven that Chlorella has the highest vitamin concentration and that, in general, green algae contain a higher proportion of thiamine, riboflavin, folic acid and carotene as compared to the plants analyzed. Finally, it has been found that algae are higher in ascorbic acid than carrots [6].

Immune system

Extensive research focused on the capacity of specified components of chlorella to stimulate the Immune System.
Its immuno-stimulating activity has been highlighted by studying a high-molecular weight polysaccharide. Indeed, this compound has turned out to be a powerful activator of monocytes and macrophages, thus modulating the immune responses [7,8].
In a clinical trial, some polysaccharides of chlorella have been found to be useful in selectively increasing the antibody response to the flu vaccine in that they are capable of stimulating the proliferation of B cells and activating macrophages [9,10].
In research carried out on tumor cells, while the Chlorella-based preparation has not shown direct cytotoxicity relative to tumor cells, the documented anti-tumor effects can be mediated by the host immune response [11]. Moreover, these polysaccharides have shown to be 101,000 times more active than the polysaccharides-based preparations currently used for cancer immunotherapy [12].

Chelating action

Chlorella has been proven to have a good potential to absorb Nickel, Copper and Cadmium [13,14,15,16]. The toxicity caused by cadmium can be alleviated by increasing its excretion through the feces: the administration of Chlorella counters heavy-metal poisoning as it is capable of decreasing tissue damage by decreasing metal absorption [17].
Other research highlighted that a higher quantity of chlorella biomass increases the quantity of bound Chromium [18] and that intake of chlorella-based preparations accelerates the excretion of Mercury, thus decreasing metal levels in tissues [19].

Anti-oxidant action

Microalgae are a major source of antioxidants, so much so that algae-based foods are consumed the world over. Chlorella contains compounds with a strong antioxidant action [20,21]. It has been proven that in jaundice, Chlorella has significant effects on the intestinal mucosa: its intake resulted in a decrease in intestinal lipid peroxidation, an increase in reduced glutathione (GSH), a decrease in oxidized glutathione (GSSG) and a significant decrease in the atrophy of villi as compared to the control group [22].

Chlorella Growth Factor (CGF)

Chorella supplementation can reduce blood pressure, lower serum cholesterol and accelerate wound healing.
The research carried out on a variety of diseases such as hypertension and ulcerous colitis has highlighted the potential of chlorella in terms of symptoms alleviation and quality of life improvement [23].
In addition, it has been pointed out that, as a diet supplement, Chlorella can help alleviate fibromyalgia symptoms [24].
The Chlorella Growth Factor (CGF), contained in chlorella extract is particularly important: it is a water-soluble extract that contains a variety of substances such as amino acids, peptides, proteins, vitamins, sugars and nucleic acids. Extensive Japanese research suggested that this compound is capable of promoting growth and healing, stimulating the immune system, offering protection from infections and exert significant antitumor activity [1,25].


Chlorella pyrenoidosa is a food known across the world for its outstanding content of amino acids, proteins, fibers and antioxidants.
Being high in active substances, it is indicated for a number of disorders: it stimulates the immune system, offers protection from infections and exerts significant antitumor activity, besides helping to reduce blood pressure and lower serum cholesterol.
Supplements that are 100% based on Chlorella pyrenoidosa and high in proteins, minerals and vitamins are interesting products from a nutritional and therapeutic point of view. Therefore, they can be indicated to boost immune defenses, chelate heavy metals and provide adequate intake of proteins and amino acids in case of protein deficiency as a result, for example, of vegetarian or vegan diets.

Authors: Dario Boschiero, Laura Converso - Date: 13/11/2013

Attention: these contents can be freely used for personal learning purposes only. The use is regulated by Law No. 633/1941 and subsequent amendments, as well as by the copyright and patent legislation in force. Any use for commercial and profit-making purposes is forbidden.


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