Microalgae are a large and polyphyletic group of O2-evolving photosynthetic microorganisms, mostly aquatic, comprising prokaryotic cyanobacteria and eukaryotic members. Estimates of the world microalgal production are around 50.000 t/year, Chlorella sp. and Spirulina sp. accounting for more than 90% of the total microalgal biomass production. These microorganisms have been widely recognized for their nutritional and therapeutic properties; therefore, a significant growth of their market is expected, especially in the nutraceutical, food, and beverage segments.
1. Introduction
The
Chlorella sp. market is expected to grow at a Compound Annual Growth Rate (CAGR) of 6.3% from 2021 to 2028, reaching USD 412.3 million by 2028
[4][1]. In terms of value, the Spirulina market is much larger and is expected to reach USD 1.1 billion by 2030, at a CAGR of 9.4% from 2023 to 2030
[5][2]. For both markets, the main growth drivers include: (1) the consumers’ greater tendency toward a protein-rich diet; (2) increasing awareness for health and wellness; (3) the growth of the nutraceutical industry; (4) an increase in vegetarianism; (5) a growing demand for natural food colors and other microalgal sourced products, such as omega-3 fatty acids; and (6) the development of innovative Chlorella food and beverage products, and products that include Spirulina as an ingredient.
Europe held the largest share of the overall Chlorella market in 2021
[4][1], where it is cultivated in closed production systems (fermenters or photobioreactors)
[6,7,8,9,10,11][3][4][5][6][7][8]. Light can support the growth of
Chlorella sp. in the photobioreactors (autotrophic conditions), while sugar-based growth is done in the dark inside fermenters (heterotrophic nutrition). The heterotrophic mode for the cultivation of
Chlorella sp. is expected to grow significantly in the next few years due to higher productivity and a lower risk of contamination, water consumption, and use of space
[4][1]. As photosynthetic organisms, microalgae have the ability to convert light energy into chemical energy. However, many species, such as
Chlorella sp.,
Spirulina (
Arthrospira) sp., can also assimilate and oxidize organic carbon molecules, extracting energy from them
[1][9]. This process can occur both in the absence of light, a condition known as heterotrophy, or in the presence of light, referred to as mixotrophy and photoheterotrophy. Although North America is expected to hold the largest share of the Spirulina market in 2030, the market in Europe is expected to register the fastest growth until 2030
[5][2]. Spirulina is cultivated in raceways, in autotrophic conditions, normally inside greenhouses in Europe and outdoor pounds elsewhere in the world
[11,12,13][8][10][11].
Chlorella vulgaris held the largest share of the overall market in 2021, but the
Chlorella pyrenoidosa or
Chlorella sorokiniana segment is expected to grow significantly in the next few years
[4][1]. Presently,
Chlorella sp. is a genus from the class Trebouxiophyceae, phylum Chlorophyta, and kingdom Plantae
[14][12]. The taxonomy of
Chlorella sp. has been evolving for decades and currently represents a group of morphologically similar species of polyphyletic origin rather than a natural genus
[15][13]. A total of 14 species are now assigned to the genus
Chlorella, including both
C. vulgaris and
C. sorokiniana. Conversely,
C. pyrenoidosa is no longer a valid name and most strains formerly identified as
C. pyrenoidosa have been renamed, although
C. pyrenoidosa strains in the literature and listed in culture collections can be found; in this case,
C. pyrenoidosa refers to strains of uncertain taxonomic status, which have not been examined for reassignment yet
[15][13]. In this research, researchers will consider the name
C. pyrenoidosa as it appears in the literature or web sources.
Regarding
Spirulina sp., a clarification is necessary. Both
Spirulina sp. and
Arthrospira sp. include cyanobacterial species very similar to each other, but the two genera are taxonomically distinct
[16][14]. Many species listed in the past as
Spirulina sp. have more recently been included in the genera
Arthrospira sp., comprising all those grown commercially and sold as Spirulina
[16,17][14][15]. Therefore, the trade name continues as Spirulina with no italics. The most important species of
Arthrospira sp. exploited for commercial mass cultivation include
Arthrospira maxima,
Arthrospira fusiformis, and
Arthrospira platensis.
2. Human Food and Nutrition
In 2021, the nutraceutical sector dominated the Chlorella market, due to the distinct properties and benefits of Chlorella as a “healthy food” that contributes to a healthy immune system and body
[4][1]. The increasing consciousness regarding health and well-being, as well as the expansion of the nutraceutical industry, highly contribute to maintaining the nutraceutical segment atop the Chlorella global market. Regarding Spirulina, the nutraceutical segment accounted for the largest share of the market, but the food and beverages segment is expected to grow significantly up to 2030, mainly due to the increasing demand for phycocyanin
[5][2].
The current dominance of the nutraceutical sector in both Chlorella and Spirulina markets is justified by their high nutritional value. Although their microalgal composition varies with culture age and cultivation conditions
[18[16][17][18],
19,20], Chlorella sp. and
Spirulina (
Arthrospira) sp. are characterized by their high protein content, low fat, suitable amino-acid profile, high concentration of vitamins (including B12), omega-3 and omega-6 fatty acids, minerals (potassium, calcium, magnesium, selenium, zinc, and others), and bioactive compounds (
Table 1).
Nutrient Composition |
Chlorella |
Spirulina |
Macronutrient (% dry weight) |
|
|
Protein |
42–65.5 |
52–72 |
Carbohydrate |
8.1–65 |
9–25 |
Lipid/fat |
1.6–40 |
1–8 |
Fiber |
1.6–6 |
2–18 |
Minerals/Ash |
6.3–27.3 |
3–13 |
Essential amino acids (mg/g protein) |
|
|
Leucine |
40–95 |
56–84 |
Phenylalanine |
20–96 |
29–48 |
Lysine |
35–82 |
35–51 |
Valine |
28–78 |
29–54 |
Isoleucine |
1.0–44 |
1.2–41 |
Threonine |
40–62 |
30–62 |
Histidine |
Table 3). Bioactive compounds from
Chlorella sp. and
Spirulina (
Arthrospira) sp., with their antioxidant and free radical scavenging abilities, are valuable in cosmetics and skincare products for their anti-aging and wrinkle-reducing potential
[59,60][57][58]. Carotenoids and peptides offer excellent UV protection in creams and sunscreens, while polysaccharides are ideal for moisturizing purposes, helping to maintain the skin’s water barrier and oil balance.
Table 3.
Bioactive compounds found in
Chlorella
sp. and
Spirulina
(
Arthrospira) sp. that are most relevant for cosmetic applications, and their corresponding activities [57,58]. ) sp. that are most relevant for cosmetic applications, and their corresponding activities [55][56].
Bioactive Compound |
Biological Activity |
Carotenoids |
Scavenges free radicals, fights wrinkles, delays aging, soothes eye skin. Antioxidant, anti-inflammatory. Provides blue light and UV protection. β-Carotene serves as a natural colorant in cosmetics. Lutein promotes regeneration of normal retinal blood vessels. |
Vitamin C |
Prevents melanin deposits, whitens the skin. Repairs the skin barrier, capillaries, and photo-aging skin, reduces erythema and telangiectasia, and lightens skin wrinkles. Stimulates collagen synthesis in the skin. |
Vitamin E |
Antioxidant. Repairs the skin barrier, treats some skin diseases. |
10–35 |
6.0–28 |
Methionine |
6.0–58 |
Polysaccharides |
16–28 |
Antioxidant, antibacterial. | Good film-forming properties, reduces water evaporation on the skin surface and provides a moisturizing effect. |
Tryptophan |
1.0–24 |
10–20 |
Other amino acids (mg/g protein) |
|
|
Aspartic acid |
38–109 |
54–118 |
Serine |
Peptides |
Anti-inflammatory. |
13–95 |
23–68 |
Glutamic acid |
76–137 |
70–105 |
| Protects skin , reduces UVB and UVC-effects. |
Flavonoids Phenols |
Antioxidant activity. Stimulates collagen synthesis in the skin, reduces wrinkle formation. |
Glycine |
60–105 |
39–78 |
Alanine |
82–159 |
Microalgal lipids play a crucial role in cosmetics, serving various functions
[58,61][56][59]. They are used as moisturizing agents, emollients, surfactants, emulsifiers, texturizers, color and fragrance carriers, preservative carriers, and bioactive ingredients. The types of microalgal lipids commonly used in cosmetics include triacylglycerides, waxes, ceramides, phospholipids, sterols, as well as hydrogenated, esterified, and oxidized lipids. Each of these lipids bring unique properties to cosmetic formulations, making them versatile and valuable ingredients in the industry.
With the increasing demand for safe and eco-friendly cosmetics and skin care products, ingredients derived from
Chlorella sp. and
Spirulina (
Arthrospira) sp. are set to take on a significant role in the industry. Their potential to provide efficient and sustainable alternatives makes them an appealing option for both cosmetic manufacturers and consumers in search of innovative and conscientious solutions. In this regard, major companies in the cosmetic industry have been incorporating
Chlorella sp. and
Spirulina (
Arthrospira) sp. into their products, especially creams and serums (
Table 4).
Table 4.
Examples of cosmetics marketed by major cosmetic companies.
Manufacturer |
Product |
Ingredient |
Ref. |
Estée Lauder |
Perfectionist Pro |
Chlorella vulgaris extract |
[62][60] |
Thalgo |
Activ Refining Blocker |
C. vulgaris extract |
[63][61] |
51–108 |
Cysteine |
2.0–35 |
2.0–6.0 |
Tyrosine |
13–84 |
|
Spiruline Boost collection (booster concentrate, antipollution gel-cream, detoxifying serum, and booster shot mask) |
Spirulina platensis extract |
[64,65,66,67][62][63][64][65] |
Institut Esthederm |
Intensive Spiruline collection (serum and crème) |
Spirulina maxima extract |
[68,69][66][67] |
Nuxe |
Merveillance LIFT collection (night cream, firming cream, lift eye cream, and firming-activating serum) |
C. vulgaris oil |
[70][68] |
Algenist |
Blue Algae Vitamin C™ Dark Spot |
Blue vitamin C, phycocyanin extracted from S. platensis extract |
[71][69] |
30–48 |
Arginine |
47–74 |
4.0–77 |
Ornithine |
1.2–1.3 |
nr |
Proline |
27–85 |
20–41 |
Fatty acids (FA) |
|
|
Saturated |
25–33 1 |
45–56 1 |
|
|
63–66 2 |
Unsaturated |
60–70 1 |
41–52 1 |
|
|
33.8–37.1 2 |
PUFA |
36–65 1 |
30–42 1 |
|
|
23.1–24.5 2 |
ω-3 |
|
0.1–0.22 |
Alpha-linolenic acid (essential FA) |
14–19.3 1 |
nr |
ω-6 |
|
23.1–24.5 2 |
Linoleic acid (essential FA) |
11–21 1 |
16–17 1 |
Vitamins (mg/100 g) |
|
|
B1 (Thiamine) |
1.5–2.4 |
3.5 |
B2 (Riboflavin) |
4.8–6.0 |
3.2 |
B3 (Niacin) |
23.8 |
12.1 |
B5 (Pantothenic acid) |
1.3 |
0.4–25 |
B6 (Pyridoxine) |
1.0–1.7 |
0.78 |
B7 (Biotin) |
191.6 |
64 |
B9 (Folic acid) |
0.61–26.9 |
0.033 |
B12 (Cobalamin) |
0.1–125.9 |
0.012–0.24 |
C (Ascorbic acid) |
15.6–100.0 |
nr |
E (Tocopherol) |
6.0–2787.0 |
2.8–75 |
A (Retinol) |
13.2 |
nr |
K |
0.033 |
2 |