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Haematococcus lacustris

Haematococcus lacustris is a unicellular, biflagellate freshwater green microalga belonging to the family Haematococcaceae in the phylum Chlorophyta, renowned for its exceptional capacity to accumulate the potent antioxidant astaxanthin, reaching up to 5% of its dry weight under environmental stress conditions such as high light intensity or nutrient deficiency.^[1]^[2] First described by J. von Flotow in 1844 and later detailed by Tracy E. Hazen in 1899, it is also known by synonyms such as Haematococcus pluvialis and Sphaerella lacustris, reflecting its historical taxonomic classification within the class Chlorophyceae and order Volvocales.^[1] The life cycle of H. lacustris encompasses distinct morphological stages, including motile macrozooids and microzooids (flagellated vegetative cells), non-motile palmella stages, and thick-walled aplanospores or hematocysts that accumulate astaxanthin and turn the cells red, serving as a protective mechanism against oxidative stress.^[1]^[3] In its green vegetative phase, the alga is rich in proteins (29–45% dry weight) and supports primary productivity, while the red cyst phase increases in lipids (up to 40%) and carbohydrates (up to 74%), enhancing its resilience in harsh environments.^[1] Ecologically, H. lacustris inhabits temporary freshwater bodies worldwide, such as rain-fed pools, ponds, and rock pools in regions including Europe, North America, Africa, and India, where it often coexists with bacterial communities in its phycosphere that may provide essential nutrients like vitamin B12.^[1]^[3] It demonstrates remarkable adaptability to a wide range of salinities, from freshwater to brackish conditions, and nutrient-poor settings, contributing to its global distribution.^[1] Biotechnologically, H. lacustris stands as the primary natural source of astaxanthin, a high-value ketocarotenoid used in aquaculture feeds (e.g., for salmon pigmentation), nutraceuticals, cosmetics, and pharmaceuticals due to its superior antioxidant properties compared to other carotenoids like β-carotene or zeaxanthin.^[2]^[1] Commercial production involves controlled stress induction in photobioreactors to maximize astaxanthin yields, with the market value estimated at $2,500–7,000 per kg as of 2014, underscoring its economic significance.^[1] Recent genomic studies have revealed a diploid nuclear genome of approximately 151 Mb containing 13,946 genes, providing insights into the evolutionary origins of its astaxanthin biosynthesis pathways and facilitating genetic improvements for enhanced production.^[2]

Taxonomy and nomenclature

Classification

Haematococcus lacustris is classified within the kingdom Plantae, division Chlorophyta, class Chlorophyceae, order Volvocales, family Haematococcaceae, genus Haematococcus, and species H. lacustris (Girod-Chantrans) Rostafinski, 1875.^[4]^[5] This hierarchy places it among the green algae, characterized by chlorophyll a and b pigments and a predominantly freshwater habitat.^[6] The basionym is Volvox lacustris Girod-Chantrans, reflecting early observations of its colonial-like appearance before recognition as a unicellular flagellate.^[5] Phylogenetically, H. lacustris belongs to the Volvocales group within the Chlorophyceae, showing close relations to genera like Chlamydomonas based on molecular data.^[7] Analyses of 18S rRNA and internal transcribed spacer (ITS) sequences confirm the monophyly of the genus Haematococcus within the family Haematococcaceae, with robust support from Bayesian posterior probabilities and maximum likelihood bootstrap values exceeding 95%.^[8] These studies highlight its position in the Chlorogonia clade, distinct yet allied with other volvocalean lineages such as Ettlia.^[8] The species H. lacustris holds type species status for the genus Haematococcus, as established by lectotype designation.^[9] H. pluvialis Flotow is recognized as a heterotypic synonym, referring to the same taxon but based on different type material; this nomenclatural resolution prioritizes H. lacustris under the International Code of Nomenclature for algae, fungi, and plants.^[9]^[5]

Synonyms and history

Haematococcus lacustris was first described as Volvox lacustris by Justin Girod-Chantrans in 1802, based on observations of specimens from stagnant waters in Switzerland.^[5] The species was later transferred to the genus Haematococcus by Józef Rostafiński in 1875, who emended the description and established the current combination Haematococcus lacustris (Girod-Chantrans) Rostafiński.^[5] Several synonyms have been used historically for this species, reflecting its varied morphological interpretations across genera. Key synonyms include Haematococcus pluvialis Flotow 1844, which was widely applied until the late 20th century and is now considered a heterotypic synonym; Sphaerella lacustris (Girod-Chantrans) Wittrock ex Hansgirg 1888; and Chlamydococcus pluvialis (Flotow) A. Braun 1850.^[10] Other notable synonyms are Byssus kermesina (Wrangel) Wahlenberg 1826 and Protococcus pluvialis (Flotow) Kützing 1845.^[10] The current acceptance of H. lacustris as the valid name follows standards from AlgaeBase and taxonomic revisions, including the designation of an epitype in 2016 to resolve nomenclatural ambiguities.^[5]^[9] In the 19th century, naturalists observed the characteristic red cysts of H. lacustris in temporary pools and rock depressions, noting their blood-like appearance due to pigment accumulation, as documented in early phycological surveys.^[10] A significant 20th-century milestone was A.M. Elliott's 1934 study on the cellular morphology and life history, which detailed the transition from green vegetative cells to red aplanospores and highlighted the species' potential as a pigment source. Recognition of H. lacustris as a rich source of astaxanthin grew in the mid-20th century through biochemical analyses of its cysts.^[1] Recent genome sequencing in 2020 confirmed the synonymy with H. pluvialis, supporting H. lacustris through phylogenetic and molecular evidence.^[11]

Morphology and life cycle

Cell structure

The vegetative cells of Haematococcus lacustris are motile, biflagellate forms that are typically oval to spherical in shape, with dimensions ranging from 8 to 20 μm in length.^[1] These cells feature a thin cell wall separated from the protoplast by a gelatinous sheath or extracellular matrix, which aids in protection and motility.^[1] Internally, they contain a prominent cup-shaped chloroplast that occupies much of the anterior region, surrounding the nucleus and featuring one or more pyrenoids for carbon fixation, as well as an anterior red stigma (eyespot) composed of lipid globules for phototactic orientation.^[1] Two equal-length anterior flagella, emerging from a papilla-like structure, enable swimming, while numerous small contractile vacuoles distributed throughout the cytoplasm handle osmoregulation in freshwater environments.^[1] Non-motile forms include palmelloid cells, which are aggregated vegetative cells embedded in a thick, amorphous gelatinous matrix secreted by the Golgi apparatus, often forming clusters up to 20-30 μm in aggregate size for temporary resting under moderate stress.^[1] Aplanospores represent larger, non-flagellated, spherical resting cells measuring 27-58 μm in diameter, with a simplified structure retaining the cup-shaped chloroplast but lacking flagella and the stigma, and featuring a thicker cell wall for enhanced durability.^[12] The cyst stage exhibits the most robust ultrastructure, with cells enlarging to 30-50 μm in diameter and developing a thick, multilayered cell wall for protection against environmental extremes.^[1] Electron microscopy reveals this wall as three-layered: an outer primary wall that often disintegrates during germination, a central trilaminar sheath with lipid bilayers, and an inner secondary wall composed of algaenan-like polysaccharides, sometimes augmented by a tertiary layer; multilamellar vesicles contribute to wall thickening.^[13] The chloroplast expands to fill nearly the entire cell volume, maintaining thylakoid membranes despite partial degradation under stress, while cytoplasmic lipid bodies—visible as electron-dense globules 1-5 μm in size—accumulate secondary carotenoids.^[1] Contractile vacuoles persist but enlarge for storage, and Golgi-derived vesicles facilitate polysaccharide deposition into the wall.^[1] Under stress, vegetative cells briefly transition to these cyst forms to enhance survival.^[1]

Developmental stages

The life cycle of Haematococcus lacustris is haplontic, characterized by a dominant haploid phase alternating between vegetative and resting stages, with no confirmed true sexual reproduction but evidence suggesting possible fusion of isogamous gametes under extreme conditions.^[14]^[6] Asexual reproduction predominates through mitotic division, ensuring propagation without meiosis except potentially in rare zygotic events.^[15] The cycle begins with spore germination, where mature cysts release haploid, biflagellate zoospores under favorable conditions such as moderate light and nutrient availability, initiating motility and dispersal. These include macrozooids, the standard larger vegetative cells, and under stress, smaller microzooids (<10 μm) that may serve as gametes.^[14]^[1] These motile cells then enter vegetative growth, dividing asexually via binary fission to produce 2–4 identical daughter cells, allowing population expansion in nutrient-rich, low-stress environments.^[15]^[14] Under adverse conditions, vegetative cells undergo encystment, shedding flagella and forming non-motile, thick-walled red aplanospores (hematocysts) in response to stressors including high light intensity exceeding 150 μmol photons m⁻² s⁻¹, elevated salinity (0.25–0.5% NaCl), or nutrient depletion such as nitrogen limitation; this transition typically occurs within 24–48 hours.^[14]^[1] During subsequent maturation, these cysts accumulate astaxanthin as a protective pigment, turning deep red and developing multilayered cell walls to enhance resilience.^[14]^[16] Excystment follows when conditions improve, with cysts germinating through multiple fission to yield 4–16 daughter zoospores per cyst, which are released to restart the vegetative phase.^[14]^[17] These resting cysts remain viable for months to years even under desiccation, enabling long-term survival in fluctuating habitats.^[18]^[19]

Habitat and ecology

Natural distribution

_Haematococcus lacustris exhibits a cosmopolitan distribution primarily in temperate zones worldwide, with reports spanning multiple continents including Europe (e.g., Greece, United Kingdom, France, Germany, Italy, Slovakia, Czech Republic, Ukraine), North America (USA, Canada, Mexico), Asia (India, Pakistan, Iran, Iraq, Israel, Malaysia), Africa (Nigeria, Egypt, Kenya, Zimbabwe), South America (Brazil, French Guiana), and Oceania (Australia, New Zealand, Hawaii), as well as the High Arctic; it is rarely documented in tropical regions.^[20] This widespread occurrence is evidenced by distributional records in over 50 countries, according to AlgaeBase data up to 2023.^[5] The species inhabits ephemeral freshwater bodies such as temporary pools, rocky depressions, shallow ponds, phytotelmata, and even artificial structures like birdbaths and concrete basins, favoring oligotrophic waters with low nutrient levels and neutral to slightly acidic pH ranging from 6 to 8.^[20]^[21] These habitats are typically shallow and exposed to high light intensities, where the alga rarely forms part of the phytoplankton community in larger, permanent lakes or rivers.^[20] Dispersal occurs primarily through air-borne resting cysts, which are highly resistant to desiccation and ultraviolet radiation, facilitating long-distance colonization of new water bodies.^[20] In terms of abundance, H. lacustris often forms blooms during summer and autumn in suitable ephemeral habitats, reaching densities up to 4 × 10⁴ cells mL⁻¹, while cysts overwinter in sediments to endure colder periods with reduced populations.^[20]

Environmental tolerances

Haematococcus lacustris exhibits remarkable abiotic tolerances that enable its persistence in fluctuating freshwater environments. It thrives across a temperature range of 8–33°C, with optimal growth occurring between 20–25°C during the green vegetative stage, while higher temperatures up to 30°C promote astaxanthin accumulation in the red cyst stage.^[22] The species demonstrates brackish water tolerance, with vegetative cells capable of growth and survival up to salinities of approximately 2 ppt (around 2 g/L NaCl), with encystment occurring as a protective response starting from 0.1 g/L NaCl and increasing significantly above 1 g/L, though growth declines sharply above 1 g/L.^[23] Desiccation-resistant cysts, or akinetes, are particularly robust, maintaining viability for up to 12 weeks (about 3 months) under low relative humidity conditions (30–50%), allowing the alga to endure prolonged dry periods in ephemeral habitats.^[24] In terms of biotic interactions, H. lacustris experiences low competition in transient, ephemeral pools where it acts as an early colonizer, rapidly exploiting reflooded conditions post-desiccation. Potential predation by protozoa is mitigated by the thick, multilayered walls of its cysts, which provide mechanical protection against grazing, though vegetative cells remain more vulnerable. Associated bacterial communities in the phycosphere play a beneficial role, facilitating nutrient cycling and enhancing algal growth and carotenoid production through symbiotic interactions, such as those involving auxin-producing bacteria that stimulate cell division. Stress responses in H. lacustris are primarily mediated by encystment, a reversible process triggered by environmental stressors including desiccation, high irradiance, and nutrient limitation, which prompts the transition from motile vegetative cells to protective, non-motile cysts enriched with astaxanthin for photoprotection. This adaptation positions the alga as a key pioneer in the succession of ephemeral pools, where cysts germinate upon rehydration to initiate blooms. Astaxanthin within cysts serves as a crucial photoprotectant against high light stress.^[25] Regarding conservation, H. lacustris is not considered threatened and holds a least concern status due to its cosmopolitan distribution and resilience, though populations exhibit locally episodic dynamics tied to habitat availability. Climate change, particularly increased frequency of drying events in the 2020s, may enhance bloom occurrences in ephemeral systems by favoring desiccation-tolerant life stages, potentially altering ecological succession patterns without posing extinction risks.^[24]

Physiology and biochemistry

Photosynthesis and metabolism

Haematococcus lacustris is a unicellular green alga that performs oxygenic photosynthesis in its chloroplasts, utilizing chlorophyll a and b as primary pigments to capture light energy.^[26] The photosynthetic apparatus includes photosystems I (PSI) and II (PSII), which facilitate linear electron transport from water to NADP⁺, producing oxygen (O₂), ATP, and NADPH for carbon fixation.^[27] This process supports the Calvin cycle for CO₂ assimilation during autotrophic growth, the dominant mode under natural and standard laboratory conditions.^[28] The alga exhibits facultative mixotrophy, where supplementation with organic carbon sources like glucose or acetate significantly enhances growth rates compared to autotrophic conditions alone.^[29] For instance, glucose can increase biomass accumulation by up to 77% over 12 days, while acetate boosts it by about 40%, often resulting in 1.8-fold higher productivity than the combined yields of heterotrophic and phototrophic modes.^[28] Heterotrophic growth is possible in the dark using acetate as a carbon source, but yields remain low, with rates substantially inferior to mixotrophic cultivation.^[30] Nutrient requirements for optimal vegetative growth include nitrogen sources such as nitrate or ammonium, phosphorus, and trace elements like iron, which support enzymatic functions in photosynthesis and metabolism.^[31] A low carbon-to-nitrogen (C:N) ratio favors biomass production in the green stage, with media formulations often maintaining ratios around 10:1 to promote cell division without inducing encystment.^[32] The preferred pH range is neutral to slightly alkaline, between 7 and 8, to maintain metabolic efficiency and prevent precipitation of nutrients.^[33] Under laboratory conditions, H. lacustris achieves biomass productivities of 0.1 to 0.3 g L⁻¹ day⁻¹, depending on light intensity, carbon supplementation, and nutrient availability.^[34] Respiration rates elevate under low-oxygen or anaerobic conditions, aiding survival during environmental stress by shifting energy allocation from photosynthesis to fermentative pathways.^[35]

Astaxanthin biosynthesis

Astaxanthin biosynthesis in Haematococcus lacustris proceeds through the carotenoid pathway, initiating from isopentenyl pyrophosphate (IPP), which is synthesized via both the mevalonate (MVA) pathway in the cytosol and the 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway in the plastid.^[1] The pathway advances with the condensation of IPP and dimethylallyl pyrophosphate to form geranylgeranyl pyrophosphate (GGPP), followed by the action of phytoene synthase (PSY) to produce phytoene, the first committed carotenoid precursor. Subsequent desaturation and cyclization steps, catalyzed by enzymes such as phytoene desaturase, ζ-carotene desaturase, and lycopene cyclase, yield lycopene and then β-carotene. β-Carotene is further modified by β-carotene ketolase (BKT), which introduces keto groups at the 4 and 4' positions, and β-carotene hydroxylase (BCH), which adds hydroxy groups at the 3 and 3' positions, resulting in astaxanthin, chemically known as 3,3'-dihydroxy-β,β-carotene-4,4'-dione.^[1]^[36] In the cyst stage, H. lacustris accumulates astaxanthin up to 4% of dry cell weight, equivalent to approximately 40,000 μg g⁻¹, primarily within lipid globules where it is esterified with fatty acids such as palmitate and stearate for stability and solubility.^[37] This accumulation imparts the characteristic red coloration to the cysts, attributable to the ketocarotenoid structure that absorbs light in the visible spectrum.^[1] Astaxanthin production is tightly regulated by environmental stresses that generate reactive oxygen species (ROS), such as high light intensity and elevated salinity, which trigger the transition from vegetative cells to stress-resistant cysts.^[38] Transcription factors, including members of the MYB and C3H families, mediate this response by upregulating key biosynthetic genes like those encoding PSY, BKT, and BCH under conditions of high light and nutrient limitation.^[39] Genome assemblies, such as the 2023 chromosome-level reference for Haematococcus pluvialis, synonymous with H. lacustris, reveal multiple BKT homologs (e.g., five identified, with tandem duplications on chromosome 26) that contribute to the pathway's efficiency.^[40] A 2025 draft assembly for the industrial strain H. lacustris Liv1 further supports ongoing research into these biosynthetic genes.^[41] Astaxanthin serves multiple protective functions in H. lacustris, acting as a potent antioxidant—approximately 10 times stronger than zeaxanthin—by scavenging ROS and preventing lipid peroxidation in cellular membranes.^[42] It also facilitates photoprotection through non-photochemical quenching (NPQ), dissipating excess light energy to safeguard photosystem II from damage during high irradiance.^[1] Additionally, astaxanthin biosynthesis is coupled with neutral lipid synthesis, enabling energy storage in the form of triacylglycerols within cyst globules for survival under prolonged stress.^[1]

Cultivation and applications

Culture techniques

Cultivation of Haematococcus lacustris typically employs a two-phase process to optimize biomass production followed by astaxanthin accumulation, mimicking its natural stress response.^[22] In the first phase, focused on green vegetative growth, cells are cultured under favorable conditions including low light intensities of 50–100 μmol photons m⁻² s⁻¹, nutrient-rich media such as BG-11 or modified BOLD, a pH of around 7.5, and temperatures of 20–25°C, achieving biomass densities of 1–5 g L⁻¹.^[22] This stage promotes rapid cell division and chlorophyll synthesis, with aeration and CO₂ supplementation often used to enhance growth rates.^[43] The second phase induces the formation of red aplanospores rich in astaxanthin through stress conditions, such as high light intensities exceeding 2000 μmol photons m⁻² s⁻¹, nitrogen starvation, and elevated salinity (e.g., 0.3 M NaCl), typically at similar temperatures but with pH maintained at 6–8.^[22] These stressors trigger encystment and carotenoid biosynthesis, resulting in a 20–30-fold increase in astaxanthin content relative to the green phase, often reaching 3–5% of dry weight.^[44] Various cultivation systems are utilized depending on scale and control needs. Closed photobioreactors (PBRs), such as tubular or flat-plate designs, offer high light utilization (80–90%) and sterile conditions, suitable for the green phase to minimize contamination, though they are capital-intensive.^[22] Open raceway ponds provide a cost-effective alternative for large-scale production but are susceptible to microbial contamination and weather variability, often reserved for the red phase outdoors.^[22] Heterotrophic or mixotrophic modes, supplemented with acetate or glucose, can yield up to 10 g L⁻¹ biomass in fermenters, bypassing light limitations but requiring careful nutrient management to avoid acetate inhibition. Defined media like BG-11 or modified BOLD are standard for axenic cultures, with sterilization via autoclaving essential to prevent bacterial overgrowth; wild-type strains (e.g., UTEX B 16) are commonly used, though select mutants may enhance stress tolerance.^[45] Key challenges include contamination control in open systems and balancing stress to avoid cell lysis, with overall astaxanthin productivities ranging from 0.02–0.1 g m⁻² day⁻¹ in PBRs based on recent optimizations.^[22]

Commercial uses

Harvesting of Haematococcus lacustris biomass typically involves centrifugation or flocculation to separate cells from the culture medium, enabling efficient recovery without excessive energy costs.^[46] Centrifugation is widely used for its reliability in large-scale operations, while flocculation, often aided by bioflocculants like chitosan, promotes cell aggregation for gravity-based settling and supports water reuse in closed-loop systems.^[47] Following harvesting, astaxanthin extraction from the robust cyst walls requires cell disruption techniques, with solvent-based methods using ethanol achieving up to 94% recovery under optimized conditions of 90% ethanol at 60°C.^[48] Supercritical CO₂ extraction, enhanced by ethanol as a co-solvent, yields high-purity astaxanthin (up to 95%) and is preferred for its environmental compatibility, producing oleoresins with astaxanthin contents of 73-83% from dry biomass that typically contains 2-5% total astaxanthin.^[49]^[50] The primary commercial product from H. lacustris is natural astaxanthin, marketed as dietary supplements for its potent antioxidant properties, with typical doses ranging from 4-12 mg per day to support eye health, skin protection, and inflammation reduction.^[51] In aquaculture, astaxanthin-enriched H. lacustris biomass serves as a feed additive at concentrations of 50-100 ppm, enhancing pigmentation in salmonids and improving growth, survival, and immune response without the limitations of synthetic alternatives.^[52] Additionally, astaxanthin extracts are incorporated into cosmetics, such as anti-aging creams and UV-protective formulations, leveraging its photoprotective and skin-rejuvenating effects at low concentrations.^[53] The global astaxanthin market was valued at approximately $800 million in 2023 and $1.6 billion in 2024, with natural sources from H. lacustris accounting for about 10-15% of supply, driven by demand for premium, bioavailable products over cheaper synthetic versions.^[54]^[55]^[56] Key producers include Cyanotech Corporation in Hawaii and Algatech Ltd. in Israel, which cultivate H. lacustris in controlled photobioreactors to meet sustainability standards and capitalize on the growing preference for natural astaxanthin in nutraceuticals and feeds.^[57] Cultivation of H. lacustris also offers environmental benefits, including CO₂ sequestration during growth, making it a greener alternative to petroleum-derived synthetics.^[1] Astaxanthin from H. lacustris holds Generally Recognized as Safe (GRAS) status from the U.S. Food and Drug Administration (FDA) for use in foods at specified levels, while for supplements, FDA has issued no-objection letters via New Dietary Ingredient Notifications affirming safety at up to 12 mg daily intake.^[58]^[59] The European Food Safety Authority (EFSA) has authorized it as a novel food, deeming oleoresin extracts safe with specifications limiting astaxanthin to 10% and confirming no adverse effects up to 16 mg daily for adults.^[60] Many commercial products achieve organic certification, underscoring the regulatory acceptance and quality assurance for H. lacustris-derived astaxanthin in global markets.^[1]

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Regulation of Two Carotenoid Biosynthesis Genes Coding for ... - NIH
Astaxanthin accumulation in H. pluvialis occurs in response to environmental stress such as high light and salt stress. Here, the isolation of the H. pluvialis ...
[41]
Transcription Factors From Haematococcus pluvialis Involved in the ...
Oct 25, 2021 · The present study provided new insight into a global view of TFs and their correlations to astaxanthin synthesis in H. pluvialis.Missing: HY5 | Show results with:HY5
[42]
A chromosome-level genome assembly for the astaxanthin ... - Nature
Aug 3, 2023 · The green microalga Haematococcus pluvialis can synthesize high amounts of astaxanthin, which is a valuable antioxidant that has been ...Missing: distinction | Show results with:distinction
[43]
Clinical Applications of Astaxanthin in the Treatment of Ocular ...
Furthermore, astaxanthin, due to the stronger antioxidant activity (about ten times higher compared to that of zeaxanthin and lutein), addresses an additional ...
[44]
https://doi.org/10.1016/j.biortech.2014.06.068
[45]
https://utex.org/products/utex-b-0016
[46]
UTEX B 16 Haematococcus lacustris
In stockFor information on the best growth conditions and media, consult other literature or conduct your own experiments. Once a stock culture is established ...Missing: cultivation | Show results with:cultivation
[47]
Extraction of Valuable Biomolecules from the Microalga ...
Feb 23, 2023 · Flotation is a gravity separation technique, and it involves attaching micro-sized air bubbles to microalgae cells. The flocculation technique ...
[48]
A circular approach for the efficient recovery of astaxanthin from ...
Aug 7, 2025 · Flocculation has been proved an efficient method for microalgal biomass harvesting, but some coagulant agents may have adverse effects on ...
[49]
Extraction and Purification of Highly Active Astaxanthin from ...
To exploit this promising source of fermentative and natural astaxanthin, an efficient extraction process using ethanol was established in this study.
[50]
Efficient supercritical carbon dioxide extraction of astaxanthin from ...
The extraction yield of astaxanthin at 65 MPa was 1.25 times and 2.32 times higher than that at 45 MPa and 25 MPa, respectively. The H-SFE extraction yield of ...
[51]
Extraction of astaxanthin from Haematococcus pluvialis by ...
Aug 4, 2025 · Under these optimum conditions, the astaxanthin yield was 73.9% (10.92 mg/g dry H. pluvialis powder) after eight cycle of extraction cycles. The ...
[52]
Astaxanthin: Sources, Extraction, Stability, Biological Activities and ...
Haematococcus pluvialis is a green microalga, which accumulates high astaxanthin content under stress conditions such as high salinity, nitrogen deficiency, ...Missing: 40000 | Show results with:40000
[53]
Astaxanthin: Feed supplement enhances pigmentation, health
Jan 1, 2007 · Astaxanthin is a carotenoid used in feed to improve pigmentation, health, and as a vitamin A precursor, and for reproductive cycles.
[54]
Astaxanthin: The Key to a New You | Clinical Education
Aug 29, 2019 · Astaxanthin, a potent antioxidant from microalgae, may benefit the brain, eyes, and skin, and is considered a potent membrane protector.<|separator|>
[55]
Astaxanthin Market Size, Share | Growth | Forecast - 2033
The global astaxanthin market was valued at $0.8 billion in 2023, and is projected to reach $1.6 billion by 2033, growing at a CAGR of 8.1% from 2024 to 2033.Missing: Haematococcus lacustris Algatech
[56]
Haematococcus Pluvialis Market to Reach $189.8 Million by 2030
May 16, 2023 · Based on product, in 2023, the astaxanthin ingredients segment is expected to account for the largest share of the global haematococcus ...
[57]
GRN No. 580 - GRAS Notices - FDA
Haematococcus pluvialis extract containing astaxanthin esters. Intended Use: Ingredient in baked goods and baking mixes, beverages and beverage bases, energy, ...Missing: lacustris | Show results with:lacustris
[58]
Safety of a change in specifications of the novel food oleoresin from ...
Nov 8, 2023 · The EFSA Panel concludes that the novel food oleoresin from H. pluvialis containing astaxanthin is safe with the proposed specification limits.Missing: lacustris GRAS FDA