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Guerin, M., Huntley, M. E. & Olaizola, M. Haematococcus astaxanthin: applications for human health and nutrition. Trends Biotechnol. 21, 210-216


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The carotenoid pigment astaxanthin has important applications in the nutraceutical, cosmetics, food and feed industries. Haematococcus pluvialis is the richest source of natural astaxanthin and is now cultivated at industrial scale. Astaxanthin is a strong coloring agent and a potent antioxidant - its strong antioxidant activity points to its potential to target several health conditions. This article covers the antioxidant, UV-light protection, anti-inflammatory and other properties of astaxanthin and its possible role in many human health problems. The research reviewed supports the assumption that protecting body tissues from oxidative damage with daily ingestion of natural astaxanthin might be a practical and beneficial strategy in health management.
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Haematococcus astaxanthin:
applications for human health and
Martin Guerin, Mark E. Huntley and Miguel Olaizola
Mera Pharmaceuticals Inc., 73 4460 Queen Kaahumanu Hwy, Suite 110, Kailua-Kona, Hawaii 96740, USA
The carotenoid pigment astaxanthin has important
applications in the nutraceutical, cosmetics, food and
feed industries. Haematococcus pluvialis is the richest
source of natural astaxanthin and is now cultivated at
industrial scale. Astaxanthin is a strong coloring agent
and a potent antioxidant its strong antioxidant
activity points to its potential to target several health
conditions. This article covers the antioxidant, UV-light
protection, anti-inflammatory and other properties of
astaxanthin and its possible role in many human health
problems. The research reviewed supports the assump-
tion that protecting body tissues from oxidative
damage with daily ingestion of natural astaxanthin
might be a practical and beneficial strategy in health
Astaxanthin is the main carotenoid pigment found in
aquatic animals and is present in many of our favorite
seafoods including salmon, trout, red seabream, shrimp,
lobster and fish eggs. It is also present in birds such as
flamingoes and quails. In many of the aquatic animals in
which it is found, astaxanthin has several essential
biological functions including protection against oxidation
of essential polyunsaturated fatty acids; protection
against UV light effects; immune response; pigmentation;
communication; reproductive behavior and improved
reproduction [1]. Some microorganisms are rich in
astaxanthin the Chlorophyte alga Haematococcus
pluvialis is believed to accumulate the highest levels of
astaxanthin in nature. Commercially grown H. pluvialis
can accumulate .30 g of astaxanthin kg
dry biomass [2].
Astaxanthin is closely related to other well-known
carotenoids, such as b-carotene, zeaxanthin and lutein,
thus they share many of the metabolic and physiological
functions attributed to carotenoids. The presence of the
hydroxyl and keto endings (Fig. 1) on each ionone ring,
explains some unique features, such as the ability to be
esterified, a higher anti-oxidant activity and a more polar
configuration than other carotenoids. Free astaxanthin is
particularly sensitive to oxidation. In nature, it is found
either conjugated to proteins, such as in salmon muscle or
lobster exoskeleton, or esterified with one or two fatty
acids, which stabilize the molecule. In H. pluvialis, the
esterified form predominates, mostly as astaxanthin
monoester [1]. Various astaxanthin stereoisomers are
found in nature that differ in the configuration of the
two hydroxyl groups on the molecule (Fig. 1). The 3S,30S
stereoisomer is the main form found in H. pluvialis and
in wild salmon [3].
Astaxanthin cannot be synthesized by animals and
must be acquired from the diet. Although mammals and
most fish are unable to convert other dietary carotenoids
into astaxanthin, crustaceans (such as shrimp and some
fish species including koi carp) have a limited capacity to
convert closely related dietary carotenoids into astax-
anthin, although they benefit from being fed astaxanthin
directly. Mammals lack the ability to synthesize astax-
anthin or to convert dietary astaxanthin into vitamin
A: unlike b-carotene, astaxanthin has no pro-vitamin A
activity in these animals [4].
Bioavailability and pharmacokinetics
The various steps of digestion, absorption and plasma
transport of dietary carotenoids in mammals have been
reviewed [5]. In the plasma, non-polar carotenoids such as
b-carotene, a-carotene or lycopene, are mostly transported
by very low density lipoproteins (VLDLs) and low density
lipoproteins (LDLs) and polar carotenoids, such as
zeaxanthin or lutein, are more likely to be transported
by LDLs and high density lipoproteins (HDLs). The only
study on humans to date confirmed the bioavailability of
astaxanthin supplied in a single high dosage of 100 mg and
its transport in the plasma by lipoproteins [6].
Astaxanthin as an antioxidant
Free radicals (e.g. hydroxyl and peroxyl radicals) and
highly reactive forms of oxygen (e.g. singlet oxygen) are
produced in the body during normal metabolic reactions
and processes. Physiological stress, air pollution, tobacco
smoke, exposure to chemicals or exposure to ultraviolet
(UV) light, can enhance the production of such agents.
Phagocytes can also generate an excess of free radicals to
aid in their defensive degradation of the invader. Free
radicals can damage DNA, proteins and lipid membranes.
Oxidative damage has been linked to aging, atherogenesis,
ischemia-reperfusion injury, infant retinopathy, age-
related macular degeneration and carcinogenesis [7].
Dietary antioxidants, such as carotenoids, might help to
prevent and fight several human diseases. Carotenoids are
Corresponding author: Miguel Olaizola (
Review TRENDS in Biotechnology Vol.21 No.5 May 2003
210 0167-7799/03/$ - see front matter q2003 Elsevier Science Ltd. All rights reserved. doi:10.1016/S0167-7799(03)00078-7
potent biological antioxidants that can absorb the excited
energy of singlet oxygen onto the carotenoid chain, leading
to the degradation of the carotenoid molecule but
preventing other molecules or tissues from being
damaged [8,9]. They can also prevent the chain reaction
production of free radicals initiated by the degradation of
poly-unsaturated fatty acids, which can dramatically
accelerate the degradation of lipid membranes. Astax-
anthin is very good at protecting membranous phospho-
lipids and other lipids against peroxidation [10,11].
Astaxanthin’s antioxidant activity has been demon-
strated in several studies. In some cases, astaxanthin has
up to several-fold stronger free radical antioxidant activity
than vitamin E and b-carotene [12,13]. The antioxidant
properties of astaxanthin are believed to have a key role in
several other properties such as protection against
UV-light photooxidation, inflammation, cancer, ulcer’s
Helicobacterpylorii infection, aging and age-related dis-
eases, or the promotion of the immune response, liver
function and heart, eye, joint and prostate health.
Astaxanthin as a photoprotectant
Exposure of lipids and tissues to light, especially UV-light,
can lead to production of singlet oxygen and free radicals
Fig. 1. Structures of selected carotenoids.
Astaxanthin 3S, 3´S
TRENDS in Biotechnology
Astaxanthin 3R, 3´S
Astaxanthin 3R, 3´R
Review TRENDS in Biotechnology Vol.21 No.5 May 2003 211
and photo-oxidative damage of these lipids and tissues [7].
Carotenoids have an important role in nature in protecting
tissues against UV-light mediated photo-oxidation and are
often found in tissues directly exposed to sunlight.
Astaxanthin can be significantly more effective than
b-carotene and lutein at preventing UV-light photooxida-
tion of lipids [14]. Oxidative damage to the eye and skin by
UV light has been widely documented [7] and thus the
unique UV protection properties of astaxanthin could be
very important for eye and skin health.
Astaxanthin and eye health
Two of the leading causes of visual impairment and
blindness are age-related macular degeneration (AMD)
and age-related cataracts. Both diseases appear to be
related to light-induced oxidative processes within the
eye [7,15]. It is therefore not surprising that factors related
to oxidation have been shown in epidemiological studies to
be related to an elevated risk for AMD. A high dietary
intake of carotenoids, specifically lutein and zeaxanthin
(from spinach, kale, and other leafy green vegetables) is
associated with a reduced risk for both nuclear cataracts
and AMD [1517]. Lutein and zeaxanthin, two carotenoid
pigments closely related to astaxanthin, are concentrated
in the macula of the eye [18].
The structure of astaxanthin is very close to that of
lutein and zeaxanthin but has a stronger antioxidant
activity and UV-light protection effect [14]. Astaxanthin
has not been isolated in the human eye. However, an
animal study [19] demonstrated that astaxanthin is
capable of crossing the bloodbrain barrier and, similar
to lutein, will deposit in the retina of mammals. The retinal
photoreceptors of rats fed astaxanthin were less damaged
by a UV-light injury and recovered faster than animals not
fed astaxanthin. Therefore, it can be inferred that
deposition of astaxanthin in the eye could provide superior
protection against UV light and oxidation of retinal
tissues pointing to the potential of astaxanthin for eye
health maintenance.
Astaxanthin and skin health
Excessive exposure of unprotected skin to sunlight results
in sunburn and can also lead to photo-induced oxidation,
inflammation, immunosuppression, aging and even car-
cinogenesis of skin cells. Pre-clinical studies show that
typical dietary antioxidants, such as a-tocopherol, ascorbic
acid or b-carotene, could reduce such damage [2022].
Astaxanthin is believed to protect the skin and eggs of
salmon against UV-light photo-oxidation [23,24]. Astax-
anthin supplementation helped protect the retinal photo-
receptors in the eyes of rats exposed to acute UV-light
injury [19] and the in vitro protective effect of astaxanthin
against UV-induced photooxidation [14] was stronger
when compared with b-carotene and lutein. These findings
suggest that astaxanthin has an excellent potential as an
oral sun-protectant. Although diet supplementation with
b-carotene or astaxanthin has demonstrated benefits in
other types of cancer, the animal or clinical studies with
these two compounds are inconclusive when it comes to
skin cancer [20,25,26]. More studies are needed to better
understand the possible interactions between various
antioxidants and their potential prooxidative role, to
determine under which conditions supplementation with
carotenoids such as astaxanthin can help reduce skin
Astaxanthin and inflammation
In inflammation-related clinical conditions such as
Crohn’s disease, toxic reactive oxygen species (ROS) are
released by phagocytic leucocytes at the site of inflam-
mation (intestinal mucosa and lumen). These, plus
increased concentrations of neutrophiles at the site of
inflammation, create a pro-oxidative balance that leads to
lower levels of antioxidant vitamins and increased levels of
markers of oxidative stress and lipid peroxidation [27].
Furthermore, oxidants have been directly linked to the
stimulation of inflammation genes in endothelial cells [28].
Similarly, ROS have been attributed an aggravating role
in the inflammation that accompanies asthma [29] and
exercise-induced muscle damage [30].
Astaxanthin was found to reduce induced swelling of rat
paw, that vitamin E did not reduce [12]. More recently,
dietary astaxanthin was found to help fight symptoms of
ulcer disease from Helicobacter pylori. Astaxanthin
reduced symptoms of gastric inflammation and was also
associated with shifts in the inflammation response [31].
Although it could be assumed that the antioxidant
properties of astaxanthin explains its anti-inflammatory
activity, further studies are needed to better understand
the specific mode of action of astaxanthin in fighting
Astaxanthin and heart health
High blood levels of LDL-cholesterol (the ‘bad’ cholesterol)
are associated with an increased risk of atherosclerosis.
However, HDL blood levels are inversely correlated with
coronary heart disease and are indicative of protection
against atherosclerosis. Usually LDL in plasma is not
oxidized and oxidation of LDL is believed to contribute to
the development of atherosclerosis [32] thus it might be
possible to reduce the risk of atherosclerosis by anti-
oxidant supplementation. Epidemiological and clinical
data indicate that dietary antioxidants might protect
against cardiovascular disease [33].
Astaxanthin is carried by VLDL, LDL and HDL in the
human blood. An in vitro test and a study with human
subjects ingesting daily dosages as low as 3.6 mg astax-
anthin per day for two consecutive weeks demonstrated
that astaxanthin protects LDL-cholesterol against
induced in vitro oxidation [34]. In an animal model
study, astaxanthin supplementation led to an increase in
blood levels of HDL [35], the form of blood cholesterol
inversely correlated with coronary heart disease. Thus,
astaxanthin could benefit heart health by modifying blood
levels of LDL and HDL cholesterol. Finally, astaxanthin
could also be beneficial to heart health by reducing
inflammation presumably associated with the develop-
ment of coronary heart disease [36].
Astaxanthin and cellular health
In the mitochondria, multiple oxidative chain reactions
generate the energy needed by the cell but produce large
Review TRENDS in Biotechnology Vol.21 No.5 May 2003
amounts of free radicals that need to be neutralized to
maintain proper mitocondrial function. It is hypothesized
that the cumulative oxidative damage to mitochondria is
the main culprit for the senescence of cells, which in turn
is responsible for aging [37]. The efficacy of astaxanthin
in preventing in vitro peroxidation of mitochondria of rat
liver cells can be as high as 100 times that of vitamin E [12].
This highlights the unique capacity of astaxanthin in
helping to preserver mitochondrial functions and its
unique potential in the fight against aging. Astaxanthin’s
superior role in protecting cellular membranes is believed
to derive from its ability to protect both the inner part and
external surface of membranes against oxidation (a result
of the moieties of its polyene chain and terminal rings as
well as of rigidifying membranes and modifying their
permeability) [3840]. Antioxidants, carotenoids in par-
ticular, are not only essential to cellular health because
they help protect cellular components against oxidative
damage but also because they have a role in regulating
gene expression and in inducing cell-to-cell communi-
cations [41,42]. Recently, astaxanthin was reported to
have a role in regulating CYP genes in rat hepatocytes,
although it did not seem to have that effect in human
hepatocytes [43]. Also carotenoids are active inducers of
communication between cells at the cell-gap junctions (the
water-filled pores in the cell membranes that permit cell-
to-cell communications needed to modulate cell growth
and, in particular, to limit expansion of cancerous
cells) [42]. Thus, it is hypothesized that carotenoids affect
DNA regulating RNA responsible for gap-junction com-
munications and that this role in cell-gap junctions
communications might explain some of the anti-cancer
activities of astaxanthin.
Anti-cancer properties of astaxanthin
Several studies have demonstrated the anti-cancer
activity of astaxanthin in mammals. Astaxanthin pro-
tected mice from carcinogenesis of the urinary bladder by
reducing the incidence of chemically induced bladder
carcinoma [44]. Rats fed a carcinogen but supplemented
with astaxanthin had a significantly lower incidence of
different types of cancerous growths in their mouths than
rats fed only the carcinogen. The protective effect of
astaxanthin was even more pronounced than that of
b-carotene [45]. Furthermore, a significant (P ,0.001)
decrease in the incidence of induced colon cancer in those
rats fed astaxanthin versus those administered only the
carcinogen was found [46]. Dietary astaxanthin is also
effective in fighting mammary cancer by reducing growth
of induced mammary tumors by .50%, more so than
b-carotene and canthaxanthin [47]. Astaxanthin inhibits
the enzyme 5-a-reductase responsible for prostate growth
and astaxanthin supplementation was proposed as a
method to fight benign prostate hyperplasia and prostate
cancer [48]. More recently, astaxanthin supplementation
in rats was found to inhibit the stress-induced suppression
of tumor-fighting natural killer cells [49]. As noted earlier,
astaxanthin’s anti-cancer activity might be related to
the carotenoids’ role in cell communications at gap
junctions, which might be involved with slowing cancer-
cell growth [42], the induction of xenobiotic-metabolizing
enzymes [50] or by modulating immune responses against
tumor cells [51].
Astaxanthin in detoxification and liver function
The liver is a complex organ in which intense catabolism
and anabolism take place. Liver functions include active
oxidation of lipids to produce energy, detoxification of
contaminants, and destruction of pathogenic bacteria,
viruses and of dead red blood cells. These functions can
lead to significant release of free radicals and oxidation
byproducts and therefore it is important to have mechan-
isms that protect liver cells against oxidative damage.
Astaxanthin is much more effective than vitamin E at
protecting mitochondria from rat liver cells against lipid
peroxidation [12]. Astaxanthin also induces xenobiotic-
metabolizing enzymes in rat liver, a process that could
help prevent carcinogenesis [52]. Astaxanthin can
induce xenobiotic metabolizing enzymes in the lung
and kidney [50].
Astaxanthin and the immune response
Immune response cells are particularly sensitive to
oxidative stress and membrane damage by free radicals
because they rely heavily on cell-to-cell communications
via cell membrane receptors. Furthermore, the phagocytic
action of some of these cells releases free radicals that can
rapidly damage these cells if they are not neutralized by
antioxidants [53]. Astaxanthin significantly influences
immune function in several in vitro and in vivo assays
using animal models. Astaxanthin enhances in vitro
antibody production by mouse spleen cells [54] and can
also partially restore decreased humoral immune
responses in old mice [55]. Other evidence also points
to the immunomodulating activity of astaxanthin on
the proliferation and functions of murine immunocom-
petent cells [56]. Finally, studies on human blood cells
in vitro have demonstrated enhancement by astax-
anthin of immunoglobulin production in response to
T-dependent stimuli [57].
Astaxanthin and neurodegenerative diseases
The nervous system is rich in both unsaturated fats (which
are prone to oxidation) and iron (which has strong
prooxidative properties). These, together with the intense
metabolic aerobic activity and rich irrigation with blood
vessels found in tissues of the nervous system, make
tissues particularly susceptible to oxidative damage [58].
There is substantial evidence that oxidative stress is a
causative or at least ancillary factor in the pathogenesis
of major neurodegenerative diseases (Alzheimer’s,
Huntington’s, Parkinson’s and amyotrophic lateral scler-
osis, ALS) and that diets high in antioxidants offer the
potential to lower the associated risks [59 62].
The above-mentioned study with rats fed natural
astaxanthin [19] demonstrated that astaxanthin can
cross the blood brain barrier in mammals and can extend
its antioxidant benefits beyond that barrier. Astaxanthin,
is therefore an excellent candidate for testing in
Alzheimer’s disease and other neurological diseases.
Review TRENDS in Biotechnology Vol.21 No.5 May 2003 213
Safety of Haematococcus astaxanthin
A recent study was designed specifically to examine the
effects by dietary astaxanthin on the health of humans
[63]. In this study, 33 healthy adult volunteers were given
natural astaxanthin supplementation over a period of 29
days. Each subject consumed daily either 3.85 mg astax-
anthin (low dose) or 19.25 mg astaxanthin (high dose).
Volunteers underwent a complete medical examination
before, during, and at the end of the study and no ill effects
or toxicity from ingestion of the astaxanthin supplement
were observed. Other studies (reviewed [63]) support the
conclusion that Haematococcus astaxanthin does not
appear to possess any health risks at the tested dosages.
Haematococcus astaxanthin supplements have been
available to the public for ,3 years. A recent survey of
consumers of a commercial Haematococcus astaxanthin
supplement indicates several benefits from astaxanthin
supplementation. Users were asked to indicate all con-
ditions from which they suffered, from a list of acute
and chronic health conditions, and for each condition
whether they had observed improvements as a result
of Haematococcus astaxanthin supplementation. Users
were also asked to compare efficacy of Haematococcus
astaxanthin supplementation with that of well-known
anti-inflammatory drugs. An improvement as a result
of Haematococcus astaxanthin supplementation was
observed in 85% of the health conditions reported
(Table 1). Of 26 comparisons with popular brands of
prescription drugs, Haematococcus astaxanthin sup-
plementation was reported to be as effective as or more
effective than the anti-inflammatory drugs in 92% of the
comparisons. Of 62 comparisons with over-the-counter
(OTC) drugs including aspirin or ibuprofen, astaxanthin
supplementation was reported as effective or more
effective in 76% of the comparisons.
Given that the possibility of placebo effect or subjective
bias cannot be ruled out in that study the interpretation
of these results must be taken with some caution.
Nevertheless, the large percentage of responses indicating
a positive effect of Haematococcus astaxanthin supplemen-
tation on health conditions that have or might have a
strong inflammation component as well as the positive
comparisons of the efficacy of the supplementation with
that of anti-inflammatory drugs are indicative of strong
anti-inflammatory properties for astaxanthin [12,31]. The
exact mode of action and circumstances under which
astaxanthin can help fight inflammation remains to be
clarified, whether it is by breaking the chain formation of
free radicals aggravating inflammation or through modu-
lation of enzyme-mediated inflammation mechanisms.
These survey results, however, support the unique
potential of astaxanthin to be used as the nutritional
component in treatment or prevention strategies against
several health problems caused by oxidative stress,
UV-light photooxidation or inflammation.
Production and future of Haematococcus astaxanthin
Commercial production of Haematococcus astaxanthin is
very recent. Astaxanthin accumulation in Haematococcus
is induced under stressful growth conditions. Thus,
producers that use large-scale, outdoor, systems have
adopted a two stage strategy whereby the first stage
consists in growing Haematococcus biomass under con-
ditions conducive to fast growth in enclosed photobior-
eactors followed by a second stage in which
carotenogenesis is induced by changing the cells’ environ-
ment to stress promoting conditions. Alternatively, Hae-
matococcus astaxanthin can be produced indoors
mixotrophically. The astaxanthin-rich cells are easily
harvested by settling and centrifugation. Then, the cell
biomass is cracked (to increase astaxanthin bioavailabil-
ity) and dried. Finally, the dried product can be directly
encapsulated or the astaxanthin extracted to be included
in nutraceutical formulations [2].
Originally, Haematococcus astaxanthin producers
attempted to enter the fish (specially salmon) feed market.
However, price competition from synthetic astaxanthin
(,US$2000 kg
) relegated Haematococcus astaxanthin
Table 1. Effect of Haematococcus astaxanthin (AstaFactor) supplementation on chronic and acute health conditions
Improves condition Does not improve condition
Health condition Number of
reports Number % Number %
Sore muscles and joints 146 128 88 18 12
Back pain 48 42 88 6 13
Cholesterol 37 29 78 8 22
Osteoarthritis 20 19 95 1 5
Prostate 15 11 73 4 27
Asthma 13 11 85 2 15
Menstrual cramps 8 6 75 2 25
Rheumatoid arthritis 7 6 86 1 14
Diabetes 5 1 20 4 80
Macular degeneration 5 3 60 2 40
Sunburn 5 5 100 0 0
Post-surgery inflammation 4 4 100 0 0
Fibromyalgia 3 3 100 0 0
Gastritis 3 3 100 0 0
Gingivitis 3 2 67 1 33
Peptic ulcers 2 2 100 0 0
Prostatitis 2 2 100 0 0
Ulcerative colitis 2 0 0 2 100
TOTAL 328 277 85 51 15
Review TRENDS in Biotechnology Vol.21 No.5 May 2003
producers to supply small, specialty markets. We believe
that present commercial producers cannot compete
against synthetic astaxanthin on price alone. However,
as production technology is optimized and production is
transferred to lower cost locales, Haematococcus astax-
anthin might compete against synthetic astaxanthin on
price. Furthermore, and as the public becomes educated
and demands natural pigmented salmon (and others) or
regulations require the use of natural feed ingredients,
Haematococcus astaxanthin could demand a premium
price over synthetic astaxanthin, as has been the case in
the vitamin E and b-carotene markets [64,65].
Alternatively, as recent research has pointed to the
possible functions of astaxanthin in the human body, a
market for nutraceutical astaxanthin has started to
develop. Although the size of this market is closely
guarded by commercial producers it is expected that it
could reach a size of several hundred million US$ within
5 to 10 years.
Based on recently published literature we conclude that
Haematococcus astaxanthin supplementation might be a
practical and beneficial strategy in health management.
This conclusion is supported by astaxanthin’s strong
antioxidant activity and its possible role in health
conditions in several tissues in the human body and by
the results of a user survey. As consumers become aware of
the putative benefits of Haematococcus astaxanthin
supplementation, and as commercial production is opti-
mized and costs lowered, the perceived market potential
for Haematococcus astaxanthin will be realized.
The authors thank J. Dore, M. Lopez and M. Unson for assistance
gathering and reviewing the published literature.
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Review TRENDS in Biotechnology Vol.21 No.5 May 2003
... Natural sources of astaxanthin include a number of microalgae including Chlorella zofingiensis, Chlorococcum sp., Haematococcus pluvialis and Dunaliella sp., the red yeast Phaffia rhodozyma, and the marine bacterium Agrobacterium aurantiacum (Yuan et al., 2002). The chlorophytes Haematococcus pluvialis and Dunaliella sp. can both accumulate significant levels of astaxanthin, exhibiting the highest capacities to naturally bioaccumulate astaxanthin (Guerin et al., 2003;Hussein et al., 2006). With regard to the commercialization of pigments in algae, β-carotene was the first high-value product to be commercially produced from a microalga Dunaliella sp. in the 1980s, followed by astaxanthin from the freshwater green alga H. pluvialis (Borowitzka, 2013). ...
... With regard to the commercialization of pigments in algae, β-carotene was the first high-value product to be commercially produced from a microalga Dunaliella sp. in the 1980s, followed by astaxanthin from the freshwater green alga H. pluvialis (Borowitzka, 2013). Considering functionality, astaxanthin has been reported to play a potential role in the prevention and treatment of a wide range of diseases, such as cancer, chronic inflammatory Algae-Based Biomaterials for Sustainable Development diseases, metabolic syndrome, diabetes, diabetic nephropathy, gastrointestinal diseases, liver diseases, neurodegenerative diseases, eye diseases, skin diseases, exercise-induced fatigue, male infertility, and HgCl 2 -induced acute renal failure (Guerin et al., 2003;Hussein et al., 2006;Yuan et al., 2011) of which numerous reviews have previously covered in substantial detail (Table 7.2). ...
... Yuan et al. (2002);Ejike et al. (2017);Yamaoka et al. (2012);Krujatz et al. (2015) Chlorococcum sp.Astaxanthin; Tissue EngineeringHaraguchi et al (2016);Yuan et al. (2002) Dunaliella sp. AstaxanthinGuerin et al. (2003);Hussein et al. (2006) Haematococcus sp. AstaxanthinYuan et al. (2002);Guerin et al. (2003);Hussein et al. (2006) Tetraselmis sp.PUFA Ejike et al. (2017); De Jesus Raposo et al. (2013); Muller-Feuga (2013) Chlamydomonas sp. ...
The field of research that explores the use of microalgae in biomedicine and health is complex and diverse. Numerous research avenues currently explore the use of microalgae in biomedicine and heath such as: focusing on establishing and boosting nutritional profiles for food applications; identification, characterisation and utilisation of microalgal metabolites with biological activity as functional ingredients and/or drugs; utilisation of recombinant technology to genetically modify the algae for use as production systems for enzymes, antibodies, growth factors, drugs, and vaccines; or the use of microalgae as a source of “biomaterial” for use in applications such as drug carriers or cellular scaffolds for tissue engineering. To illustrate the diversity of microalgae and its potential for utilisation in a wide variety of biomedical and heath care applications, this chapter will present a concise overview of this broad applicability of microalgae in biomedicine and health, while highlighting research that is also occurring into the production and biorefinery of these compounds to facilitate a viable transition from laboratory to commercial production. Thus, this chapter aims to bridge the knowledge gap between both existing and potentially new algae applications, in particular, the use of microalgae as a source of “biomaterials” for biomedicine and health applications.
... Even so, obtaining three or more products could create higher revenue than using the whole biomass or extracting an astaxanthin-lipid product only. TAGs can be used for biodiesel or ingested as nutraceuticals [23,24]. Starch can be used as a bioethanol feedstock or for bioplastics [25,26]. ...
Full-text available
Biorefinery approaches offer the potential to improve the economics of the microalgae industry by producing multiple products from a single source of biomass. Chromochloris zofingiensis shows great promise for biorefinery due to high biomass productivity and a diverse range of products including secondary carotenoids, predominantly astaxanthin; lipids such as TAGs; carbohydrates including starch; and proteins and essential amino acids. Whilst this species has been demonstrated to accumulate multiple products, the development of an integrated downstream process to obtain these is lacking. The objective of this review paper is to assess the research that has taken place and to identify the steps that must be taken to establish a biorefinery approach for C. zofingiensis. In particular, the reasons why C. zofingiensis is a promising species to target for biorefinery are discussed in terms of cellular structure, potential products, and means to accumulate desirable components via the alteration of culture conditions. Future advances and the challenges that lie ahead for successful biorefinery of this species are also reviewed along with potential solutions to address them.
... 2), which can be retained in oil during the extraction process. Carotenoids are important natural antioxidants reacting as reactive oxygen and radical scavengers and quenchers of UV irradiation (Subagio and Morita, 2001;Guerin et al., 2003). It has been proposed that carotenoids increase during the cell lipid accumulation step of fermentation to protect PUFAs against oxidation reactions (Morabito et al., 2019). ...
Full-text available
The health benefits of a diet rich in omega-3 long chain polyunsaturated fatty acids (n-3 LC-PUFA) no longer need to be proven. However, while health authorities attempt to increase the consumption of the n-3 LC-PUFAs eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), data from the latest intake surveys demonstrate that EPA and DHA consumption is still too low. A push towards greater sustainability, and a rise in vegetarianism are pushing manufacturers to move from traditional fish oils towards alternative sources. Microalgae oils provide a source of n-3 LC-PUFA with a lower environmental impact and are produced using processes that limit damage to the oils. This review aims to report on oleaginous microalgae strains available for n-3 LC-PUFA production, the processes used for their growth and the extraction and refining processes for their oils. It also addresses the challenges inherent in these products and their fabrication, and some of the novel characteristics of microalgal oils, including their very high n-3 LC-PUFA content and the chemical structure of their triglycerides, that lead to exciting opportunities in their use as functional food ingredients.
... Due to the central chain of conjugated double bonds, it has the ability to donate electrons and thus neutralise reactive oxidative molecules. Due to these properties, astaxanthin has antioxidative properties and antiinflammatory properties [6] and beneficiary potential in human health [7]. ...
Full-text available
Xanthophyllomyces dendrorhous DSM 5626 is a basidiomycetous yeast [1]. It produces the carotene Astaxanthin, which is used in fish farming and gives the flesha characteristic salmon colour [2–5]. Astaxanthin has antioxidative properties and is said to have anti-inflammatory properties [6] and potential in human health [7]. Currently, in the industry astaxanthin is isolated from the algae Haematococcus pluvialis. Recent studies have shown that the yield of astaxanthin in X. dendrorhous can be increased by optimizations in the medium composition [8–10]. In the BIVAC project, several vegetable residue streams were analysed for their composition. Many of them contained sugars and proteins, which could have a positive influence on the production of astaxanthin in X. dendrorhous, so we analysed the astaxanthin levels in X. dendrorhous after cultivation in media with different watery extracts of these residue streams; these results are presented here. The process could contribute to the utilization of surplus biomass and provide a possible path to sustainable biomass use in a rapidly changing world.
... In photosynthetic marine organisms, carotenoids perform as light energy harvester. Carotenoids act as antioxidants due to their complex ring structure which are able to inactivate harmful reactive oxygen species (Guerin et al., 2003;Lesser, 2006). Animals are unable to synthesize carotenoids; they deposit these from the plants they eat. ...
Full-text available
Aquafoods are diverse and rich in containing various health functional compounds which boost natural immunity. In this manuscript, the contents of biofunctional compounds such as vitamins, minerals, protein and amino acids, ω-3 polyunsaturated fatty acids, and pigments, etc. in various aquafoods like fishes, molluscs, crustaceans, seaweeds etc. are reported. The functional roles of those compounds are also depicted which enhance the immunecompetence and immunomodulation of the consumers. This paper provides an account of the recommended daily dietary intake level of those compounds for human. Those compounds available in aquafoods are recommended as they fight against various infectious diseases by enhancing immunity. Available reports on the bioactive compounds in aquafoods reveal the immunity boosting performances which may offer a new insight into controlling infectious diseases.
... Astaxanthin is a secondary carotenoid with a chemical structure of 3,3'-dihydroxy-4,4'-diketo-β, β'-carotene, which is known for its strong antioxidant activity. It is widely found in nature, such as leaves, flowers, fruits, feathers of flamingos, most fishes, members of the frog family, crustaceans, and the unicellular alga, Haematococcus pluvialis, which is the most ideal source of natural astaxanthin [17,19] . At present, astaxanthin is mainly obtained by the biological extraction of aquatic products and by artificial synthesis from carotene as the raw material. ...
Full-text available
Nonalcoholic fatty liver disease is a major contributor to chronic liver disease worldwide, and 10%-20% of nonalcoholic fatty liver progresses to nonalcoholic steatohepatitis (NASH). Astaxanthin is a kind of natural carotenoid, mainly derived from microorganisms and marine organisms. Due to its special chemical structure, astaxanthin has strong antioxidant activity and has become one of the hotspots of marine natural product research. Considering the unique chemical properties of astaxanthin and the complex pathogenic mechanism of NASH, astaxanthin is regarded as a significant drug for the prevention and treatment of NASH. Thus, this review comprehensively describes the mechanisms and the utility of astaxanthin in the prevention and treatment of NASH from seven aspects: antioxidative stress, inhibition of inflammation and promotion of M2 macrophage polarization, improvement in mitochondrial oxidative respiration, regulation of lipid metabolism, amelioration of insulin resistance, suppression of fibrosis, and liver tumor formation. Collectively, the goal of this work is to provide a beneficial reference for the application value and development prospect of astaxanthin in NASH.
... Hematococcus pluvialis (Chlorophyceae) is a green freshwater microalga with a potential ability to accumulate excessive amounts of astaxanthin (about 1.5-6% on a dry weight basis) (Orosa et al., 2005). Globally, astaxanthin production from H. pluvialis has reached the largest industrial scale for manufacturing several nutraceuticals, medicinal, and cosmetic products for human uses (Guerin et al., 2003). Astaxanthin from this microalga is defined by its powerful antioxidative characteristics (Kobayashi, 2000), which is regarded as ten times greater than that of lutein, canthaxanthin, and zeaxanthin (Kamath et al., 2008). ...
Full-text available
Farmed fish and shrimp are continuously challenged by multiple stressors during their life stages, such as hypoxia, pH fluctuations, different salinities, high nitrite, un-ionized ammonia, injury during handling, inadequate nutrition, or food shortage, which can eventually adversely impact their health, welfare, and growth rates. Besides, these stressors can weaken production and decrease their resistance to diseases. Scientists and researchers have been making concerted efforts to find new, safe, and inexpensive supplements to mitigate the negative influences of stressors and thereby enhance the productivity of farmed aquatic animals. Some micro-algae are microscopic unicellular organisms that were found to be promising feed supplements due to their richness in important nutrients such as minerals and vitamins. Moreover, some microalgae contain several bioactive phytochemicals that exhibit anti-inflammatory, antioxidant, and immunomodulatory properties. Several field-controlled studies provided evidence that using microalgae as feed supplements led to improved growth, physiological functions, immunity, antioxidant capacity, and disease resistance in farmed finfish and shellfish species. This review article emphasizes the beneficial role of the cyanobacterium Arthrospira platensis and seven microalgal species, including Chlorella vulgaris, Parietochloris incisa, Dunaliella salina, Aurantiochytrium sp., Haematococcus pluvialis, Tetraselmis sp., and Nannochloropsis oculata in mitigating stress effects in farmed finfish and shellfish species. The conclusions of this article throw light on the potential benefits of using microorganisms in aquaculture.
Astaxanthin (AST) is a type of ketone carotenoid having significant antioxidation and anticancer abilities. However, its application is limited due to its low stability and bioavailability. In our study, poly (lactic-co-glycolic acid) (PLGA)-encapsulated AST (AST@PLGA) nanoparticles were prepared by emulsion solvent evaporation method and then further processed by ultrasound with broccoli-derived extracellular vesicles (BEVs), thereby evolving as BEV-coated AST@PLGA nanoparticles (AST@PLGA@BEVs). The preparation process and methods were optimized by three factors and three levels of response surface method to increase drug loading (DL). After optimization, the DL was increased to 6.824%, and the size, polydispersity index, and zeta potential of AST@PLGA@BEVs reached 191.60 ± 2.23 nm, 0.166, and −15.85 ± 0.92 mV, respectively. Moreover, AST@PLGA@BEVs exhibited more notable anticancer activity than AST in vitro. Collectively, these results indicate that the method of loading AST in broccoli-derived EVs is feasible and has important significance for the further development and utilization of AST as a functional food.
This review summarises recent research on metobolic engineering approaches towards terpenes, including work to investigate unknown pathways and to improve accessibility of known compounds.
Full-text available
Objective. —To evaluate the relationships between dietary intake of carotenoids and vitamins A, C, and E and the risk of neovascular age-related macular degeneration (AMD), the leading cause of irreversible blindness among adults.
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Alzheimer's disease (AD) is a common type of dementia or decline in intellectual function first described by A. Alzheimer [1907]. Some of the characteristics include intraneuronal fibril-lary tangles, diffuse, neuritic and burned-out plaques and neu-ronal loss [Harman, 1995; Lippa et al., 1996]. Epidemiological studies have not identified causal factors for Alzheimer's disease as seen in a number of reviews [Heyman et al., van Duijn, 1996]. However, recently sev-eral orally ingested substances have been found to delay the onset or progression of AD: estrogen [Tang et al., 1996b]; non-steroidal antiinflammatory drugs (NSAIDs) [Stewart et al., 1997]; and vitamin E [Sano et al., 1997].
Full-text available
The present study was performed to determine whether genistein could inhibit in vivo LPS-induced alveolar macrophage TNF production and thus reduce the alveolar neutrophil influx following LPS. In vitro incubation with genistein completely inhibited LPS-induced TNF production by alveolar macrophages (AM) from BALB/c mice. Subsequently mice were pretreated with intraperitoneal genistein or vehicle, then received nasal LPS to induce an alveolitis. Genistein was then administered every eight hours for five days following LPS. At 24 hours after LPS, the bronchoalveolar lavage (BAL) TNF and ex vivo TNF production from AM, were lower in the genistein treated animals. As well, total BAL white blood cell (WBC) count was reduced in the genistein as compared to the vehicle-only group. The percent neutrophils and the resolution of neutrophils were similar between genistein and vehicle groups. Therefore, genistein was able to decrease AM TNF production, and was associated with a decrease in BAL WBC count post-LPS.
Objective: To investigate whether high dietary intake of antioxidants decreases the risk of Parkinson disease (PD). Setting: The community-based Rotterdam Study, the Netherlands. Design: The cross-sectional study formed part of a large community-based study in which all participants were individually screened for parkinsonism and were administered a semiquantitative food frequency questionnaire. The study population consisted of 5342 independently living individuals without dementia between 55 and 95 years of age, including 31 participants with PD (Hoehn-Yahr stages 1-3). Results: The odds ratio for PD was 0.5 (95% confidence interval [CI], 0.2-0.9) per 10-mg daily dietary vitamin E intake, 0.6 (95% CI, 0.3-1.3) per 1-mg beta carotene intake, 0.9 (95% CI, 0.4-1.9) per 100-mg vitamin C intake, and 0.9 (95% CI, 0.7-1.2) per 10-mg flavonoids intake, all adjusted for age, sex, smoking habits, and energy intake. The association with vitamin E intake was dose dependent ( P for trend=.03). To assess whether the association was different in participants with more advanced disease, we excluded those with PD who had a Hoehn-Yahr stage of 2.5 or 3. This did not fundamentally alter the results. Conclusion: Our data suggest that a high intake of dietary vitamin E may protect against the occurrence of PD.
To understand the roles of carotenoids as singlet oxygen quenchers in marine organisms, quenching activities of eight major carotenoids, astaxanthin, canthaxanthin, β-carotene, zeaxanthin, lutein, tunaxanthin, fucoxanthin and halocynthiaxanthin were examined according to the method using a thermodissociable endoperoxide of 1,4-dimethylnaphthalene as a singlet oxygen generator. The second-order rate constant for the singlet oxygen quenching activity by each carotenoid was determined, suggesting that an increasing number of conjugated double bonds in carotenoid was proportional to greater quenching activity. The quenching activity of each carotenoid was found to be approximately 40 to 600 times greater than that of α-tocopherol. The potency of these carotenoids suggests that they may play a role in protecting marine organisms from active oxygen species.
Human metabolism of carotenoids is of interest not only because of the provitamin A function of certain carotenoids, but also because these compounds have been associated with reducing risks of certain cancers and chronic diseases. Full understanding of carotenoid metabolism is complicated by a number of factors: variations in physiochemical properties among carotenoids; altered carotenoid utilization as a result of the normal vicissitudes of lipid absorption and transport; divergence in metabolic fate within the intestinal enterocyte (especially carotenoid cleavage to retinoids); differences in packaging and transport in lipoproteins; dissimilarity in tissue uptake of specific carotenoids; and the possible isomerization of carotenoids within tissues. Hampering research progress is the lack of animal models that perfectly mimic human carotenoid metabolism and the limited number of carotenoids approved for human consumption in a pure form.
Reactive oxygen species are potentially damaging molecules. An important function of antioxidants is to intercept harmful triplet states, in order to prevent the formation of singlet oxygen, or to quench singlet oxygen directly. However, antioxidants are also reactive towards other active oxygen species such as the hydroxyl radical, the superoxide anion and the non-excited oxygen ground state in the presence of radical initiators. It is well known that flavonoids and carotenoids show strong antioxidant properties. Polyenes and carotenoids are the best known among the compounds that quench singlet oxygen by efficient energy transfer. A large number of modified, synthetic analogues and derivatives have been synthesised to prepare even better quenchers than the natural carotenoids. Phenols are also excellent chain-breaking antioxidants. Recently, many indigoid dyes (including bacterial indigoids) were studied, with the remarkable result that most, but not all, members of this class of chromophores quench singlet oxygen at the diffusion limit and some of them are excellent radical traps. It has been shown in this study that a quantitative assessment of antioxidant properties of flavonoids, carotenoids, phenols and natural indigoids can be achieved using the following three assays: (1) oxygen pressure dependence; (2) peroxide formation; (3) singlet oxygen quenching. Reactivities towards both excited states and ground state radicals can be properly described by these assays. The remarkable role of -carotene as an ‘unusual antioxidant’ (Burton GW and Ingold KU, Science 224: 569–573 (1984)) in reactions using various oxygen pressures becomes clearer. The so-called ‘pro-oxidant effects’ concern primarily the antioxidant itself and its degradation, since no or very little damage to the substrate occurs in this type of experiment. Three main categories of antioxidants may be classified: (1) excellent antioxidants that perfectly quench excited states as well as ground state radicals (eg actinioerythrol, astaxanthin); (2) good antioxidants that strongly inhibit peroxide formation but are less efficient in quenching excited states (eg flavonols, tocopherols) or lead to considerable degradation of the antioxidant itself (eg -carotene, lycopene); (3) moderate antioxidants that fail to excel in both reactivities (eg -carotene, flavone).© 2001 Society of Chemical Industry
This study was aimed at evaluating the antioxidant activity of polar carotenoids (zeaxanthin, astaxanthin, and astaxanthin-β-glucoside) in free radical-mediated oxidation of phosphatidylcholine (PC) liposomes. In 1-palmitoyl-2-linoleoyl-PC liposomes, astaxanthin-β-glucoside was the most active, followed by astaxanthin, zeaxanthin, and β-carotene, although there was no significant difference in the antioxidant activity of these carotenoids in chloroform solution. Thus, it is suggested that the different antioxidant activity of four kinds of carotenoids found in the PC liposomes would depend not on their ability to scavenge free radicals, but on other factors such as their location and orientation in PC liposome systems and the degree of their incorporation into PC bilayers. These physicochemical properties would be strongly correlated with the structural acceptability between the PC molecule and carotenoid molecule, especially between two polar groups of the PC bilayer and the carotenoid. Furthermore, two polar groups of the carotenoid can act as trans-bilayer rivets. The tightly packed conformation of PC bilayers caused by this function of the dipolar carotenoid would also be correlated with their antioxidant activity. This was suppported by the result that cholesterol, known as acting like a peg through one half of the bilayer, also increased the oxidative stability of PC liposomes.