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Factors That Influence the Bioavailablity of Xanthophylls


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Symposium: Can Lutein Protect Against Chronic Disease?
Factors That Influence the Bioavailablity of Xanthophylls
Susan Zaripheh and John W. Erdman, Jr.
*Division of Nutritional Sciences and Department of Food Science and Human Nutrition, University of Illinois,
Urbana-Champaign, IL 61801
KEY WORDS: bioavailability lutein xanthophyus zeaxanthin
Epidemiologic and animal studies have demonstrated that
carotenoid-rich diets are associated with a number of health
benefits (1). The potential health benefits of carotenoids, such
as their ability to act as antioxidants, immunoenhancers and
inhibitors of premalignant lesions, (2) have stimulated inves-
tigators’ interest. One of the most biologically plausible roles
for carotenoids is the potential effect of dietary lutein and
zeaxanthin for protection of the macula from degeneration
(3,4). These possible health benefits seem to relate to the
unique geometry of carotenoids.
Carotenoids are nonpolar compounds, which are divided
into two subclasses, i.e., more polar compounds called xantho-
phylls, or oxycarotenoids, and the nonpolar hydrocarbon car-
otenes. Both classes have at least nine conjugated double
bonds, which absorb specific wavelengths of visible light and
thus provide carotenoids their characteristic colors. At the end
of the polyene chain, at least one unsubstituted B-ionone ring
must be present to have provitamin A activity (5). Xantho-
phylls have ring structures at the end of the conjugated dou-
ble-bond chain with polar functions, such as hydroxyl or keto
groups (6). Examples of xanthophylls include lutein, zeaxan-
thin, capsanthin, canthaxanthin, astaxanthin, echionine and
-cryptoxanthin. Small quantities of mono- and diester forms
of lutein and zeaxanthin have been identified in foods (7), and
some dietary lutein supplements are sold in the diester form.
Papaya, peaches, prunes and squash all contain lutein diesters,
whereas squash also contains lutein monoesters and peaches
also contain zeaxanthin diesters (7). When fed at physiologic
levels, mono- or diester forms must be deesterified before lutein or
zeaxanthin absorption. Hydrocarbon carotenes include
-carotene and lycopene. (See Fig. 1.)
Due to the large vitamin A–deficient population through-
out the world, most carotenoid research has focused on hydro-
carbon carotenes, particularly the provitamin A carotenes. In
recent years, the focus has shifted to other carotenoids, par-
ticularly the oxycarotenoids (2). Xanthophylls of current in-
terest include lutein, zeaxanthin and canthaxanthin. Lutein
and zeaxanthin have been the primary focus because they are
found specifically sequestered in the macula of the eye. In
addition, there is evidence to suggest that lutein and zeaxan-
thin may also play a role in the prevention of epithelial
cancers (8), cataract and other blinding disorders. Cantha-
xanthin has been used as a food-coloring agent and as part of
tanning tablets (9).
The focus of this paper will be to review the current
research on the bioavailability of xanthophylls with particular
attention to the differential absorption of food and supplemen-
tal sources of xanthophylls. Although there is strong evidence
to show that carotenoids have limited or poor absorption from
foods, many supplemental forms of carotenoids prove to have
higher bioavailability. Deming and Erdman (10) recently re-
viewed the factors affecting the bioavailability of carotenes.
Uptake and absorption of xanthophylls
The process of nutrient absorption requires movement of
the digested food components into the mucosal cells of the
intestinal wall. Uptake occurs when the xanthophyll or its
metabolites enter the intestinal mucosal cells. Absorption is
achieved with the movement of the xanthophyll or its bioac-
tive metabolite through the mucosal cells into the portal or
lymphatic system. Xanthophyll bioavailability can be defined
as the proportion of the ingested xanthophyll that is made
available (i.e., delivered to the bloodstream) for its intended
mode of action.
Four major events must take place for optimal absorption of
xanthophylls (10). First, xanthophylls must be released from
their food matrix. This process is not efficient as detailed
The second step of absorption is the transfer of xantho-
phylls to lipid micelles in the small intestines. This requires
the presence of dietary fat in the small intestine, which stim-
ulates the gallbladder to release bile acids (i.e., emulsifiers).
Bile acids are synthesized by the liver and are composed of
both polar and nonpolar ends, which allow binding of both
Presented as part of the symposium “Can Lutein Protect Against Chronic
Disease? A Multidisciplinary Approach Involving Basic Science and Epidemiology
to Weigh Evidence and Design Analytic Strategies,” given at Experimental Biology
01, Orlando, FL, on April 2, 2001. This symposium was sponsored by the
American Society for Nutritional Sciences and supported in part by an educa-
tional grant from Kemin Foods, Cognis Corporation, United States. Guest editors
for the symposium publication were Julie A. Mares-Perlman, University of Wis-
consin-Madison, and John W. Erdman, Jr., University of Illinois at Urbana-Cham-
This material is based upon work supported by the IFAFS/U.S. Department
of Agriculture under Award no. 00-52101-9695. Any opinions, findings and con-
clusions or recommendations expressed in this publication are those of the
authors and do not necessarily reflect the views of the U.S. Department of
To whom correspondence should be addressed.
0022-3166/02 $3.00 © 2002 American Society for Nutritional Sciences. J. Nutr. 132: 531S–534S, 2002.
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lipophilic and hydrophilic molecules. Released xanthophylls
then must be assimilated into the mixed lipid micelles in the
lumen of the small intestine, most likely orienting themselves
at the micelle surface. Polar compounds make up the exterior
of the micelle, acting as a carrier for the xanthophylls to travel
through the hydrophilic chyme in the intestine to the intes-
tinal mucosal cell surface.
The third step is uptake by intestinal mucosal cells. It is
thought that xanthophylls passively diffuse through the cell
membrane and are released into the enterocyte. Some of the
xanthophylls that are taken up by the mucosal cell are not
absorbed because they are returned to the lumen of the intes-
tine with the turnover of the mucosal cells, which have a
half-life of 3d.
The nal step in absorption is the transport of the xantho-
phylls or their metabolic products to the lymph system. In the
Golgi of the enterocyte, xanthophylls are incorporated into
chylomicrons. Due to their polarity, it is hypothesized that
xanthophylls are surface oriented (4,5,1012). The chylomi-
crons are eventually delivered to the blood stream and through
the action of lipoprotein lipase, chylomicrons lose triglyceride
content and shrink in size. It is postulated (10) that nontrig-
lyceride components of the chylomicron, including surface
molecules such as xanthophylls may be taken up by extra
hepatic tissues or transferred to other blood lipoproteins.
Eventually, the chylomicron remnant, including the remain-
ing xanthophylls is taken up by the liver. Xanthophylls then
can remain in the liver or be transported to the bloodstream by
VLDL. They then are transferred to LDL and HDL with
maturation of the lipoproteins. Tissues differentially take up
carotenoids, with lutein and zeaxanthin specically accumu-
lating in the macula region of the eye.
Factors effecting bioavailability
Lutein, zeaxanthin and canthaxanthin are present predom-
inantly in green leafy vegetables and in fruit. Carotenoids are
particularly concentrated in chromoplasts or chloroplasts of
plant foods and are noncovalently bound to protein or ber,
dissolved in oil or exist in crystalline form (12,13), making
optimal absorption difcult to achieve (10). Some major fac-
tors limiting the availability of xanthophylls include physical
disposition in food sources (food matrix), structure of the
xanthophyll molecule, interaction of xanthophylls with other
nutrients (mainly dietary fat) and malnutrition (2).
Food processing such as grinding, fermentation and/or mild
heating usually improves bioavailability, most likely as a result
of weakening the cell wall of plant tissues, dissociating the
protein-oxycarotenoid complexes and/or dissolving the crys-
talline carotenoid complexes (5,10). Factors such as general
malnutrition or intestinal parasites have been found to sub-
stantially reduce the efciency of carotenoid absorption (14).
Human bioavailability studies
Effect of xanthophyll esterification, isomerization and di-
etary fat. How much fat is required to achieve maximal
absorption of xanthophylls or xanthophyll esters? Could the
more hydrophobic xanthophyll esters be distributed differently
in the lipoproteins, affecting transfer among lipoproteins?
These questions have been addressed only partially.
-carotene as the representative carotenoid, Jayara-
jan et al. (15) concluded that at least5gofdietary fat in the
same meal as
-carotene was necessary for optimal carotenoid
absorption. A more recent study (16) tested the effects of
dietary fat on the bioavailability of lutein diester,
-carotene and vitamin E in humans. The experimental de-
sign included two 7-d periods,with a 5-wk washout period
between each test period. The control group received a pla-
cebo supplement and the experimental groups received sup-
plements of vitamin E, lutein esters or a combined dose of
-carotene supplements, which were ingested as part of
either a high or low fat spread in a crossover design. The low
fat meal contained3goffat, whereas the high fat meal
contained 36 g of fat. The increased plasma concentrations of
vitamin E,
-carotene and
-carotene were not signicantly
changed by the amount of fat in the spread. However, the
lutein diester supplement did show a signicant enhancement
in absorption (as measured by increase in serum carotenoid)
with the higher dietary fat (207% increase with the high fat
spread and 88% increase with the low fat spread). From these
ndings, it may be concluded that a limited amount of fat is
required for optimal intestinal uptake of the hydrocarbon
carotenes or vitamin E, whereas a greater amount of fat is
required for the optimal deesterication of lutein esters and
absorption of lutein. Thus, 3 g of fat were required for the
sufcient solubilization of lutein diesters and/or secretion of
esterases and lipases from the pancreas. The hydrolysis of
lutein esters is mediated by these enzymes and is regulated by
the presence of fat in the stomach and the duodenum (16).
The diester form of lutein is more hydrophobic, making it
more difcult to solubilize.
At levels found in foods, lutein mono- and diesters are
poorly absorbed without deesterication. Therefore, lutein es-
ters are not normally found in chylomicrons or in blood serum.
However, Granando et al. (17) detected lutein esters in serum
of subjects who received a supplement of 15 mg lutein/d as
mixed esters for 4 mo. This dose level is 10 times the average
U.S. intake of lutein (18) and likely exceeds the maximal
deesterication activity of the enzymes in the gastrointestinal
tract. Three weeks after completion of supplementation, the
lutein diesters disappeared from the serum. Therefore, the
presence of lutein esters in serum is reversible and is found
only when total serum lutein concentrations are 1.05
mol/L (17). More research is required to determine whether
mono- or diester forms of lutein are taken up into specic
tissues, e.g., the retina.
A recent study adopted the method used to radiolabel
-carotene with C
via algae (19,20) and applied it to lutein
(21). Four women ages 2538 y were fed a strict diet of 14% of
total energy from protein, 59% from carbohydrates and 27%
from fat. Lutein was successfully radiolabeled with the stable
isotope and fed as part of a low carotenoid meal. After the
meal, blood was taken over the next 528 h. C
Lutein was
detected in plasma almost immediately and increased rapidly
to its single plasma peak at 16 h (21). This innovative ap-
FIGURE 1 Chemical structures of the selected carotenoids.
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proach has the potential to be used to evaluate the differential
absorption of free, mono- and diester lutein, as well as oxida-
tive products, which are proposed to be present in serum (14).
The variable structures of xanthophylls could have an effect
on their tissue uptake. An example, is astaxanthin whose
predominant form in nature is all-trans astaxanthin but other
isomers such as 9cis-, 13cis- and 15cis- isomers have also been
detected. In one study, Osterlie et al. (22) examined the
distribution of and the rate at which isomers of astaxanthin
appeared in plasma. The plasma appearance and distribution
of astaxanthin trans/cis and R/Sisomers in plasma lipoproteins
of three men was detected after ingestion of a single 100-mg
dose. The astaxanthin dose was made up of 74% all trans-
astaxanthin, 9% 9cis-astaxanthin, and 17% 13cis-astaxanthin.
The astaxanthin levels in the plasma were measured for 72 h
and the maximum peak was reached at 7hat1.30.1
mg/L. The plasma elimination half-life was found to be 21
11 h. This study found that astaxanthin accumulates selec-
tively in the VLDL-containing chylomicrons, whereas 29
and 24% were distributed within LDL and HDL, respectively.
The relative proportion of astaxanthin cis-isomers compared
with all-trans-astaxanthin was increased apparently due to its
selective absorption of cis isomers. However, the pharmacoki-
netics of astaxanthin isomers are similar to each other (22).
Effects of other food components on bioavailability. It is
important to determine the effects of other food components
on the bioavailability of xanthophylls. For instance, the bio-
availability of both lutein and canthaxanthin can be reduced
signicantly when they are consumed with some forms of
dietary ber (23,24). Another food component that has been
shown to reduce bioavailability of carotenoids is the fat sub-
stitute, sucrose polyester (SPE). A signicant reduction of
lutein and zeaxanthin was found in human plasma with 3g/d
consumption of SPE; however, SPE does have a greater effect
on carotenes than xanthophylls. SPE affects carotenoid ab-
sorption when consumed in the same meal as the carotenoids
Interaction among carotenoids
When a diet is high in carotenoid-rich foods, it will usually
be high in several carotenoids; thus, it is important to deter-
mine whether there are interactive effects among carotenoids.
In addition, the use of high dose, single-carotenoid supple-
ments in clinical trials or for self-medication increases the risk
of negative interactions. The question of whether oxygenated
xanthophylls are absorbed more rapidly than carotenes was
addressed in a pharmacokinetics study of
-carotene and can-
thaxanthin. Two subjects ingested either a 25-mg dose of
canthaxanthin, a 25-mg dose of
-carotene or a combined
dose of canthaxanthin and
-carotene, which contained 25
mg of each over three 5-d study periods. The order of carot-
enoid treatments varied among the subjects, i.e., either can-
thaxanthin or a combined dose of
-carotene and canthaxan-
thin were administered for the rst and second study periods.
After a 33-wk washout period the subjects ingested an indi-
-carotene dose. It was concluded that canthaxanthin
did not inhibit the appearance of
-carotene in serum. How-
ever, this combined dose did reduce the bioavailability of
-Carotene reduced the serum canthaxanthin
concentration by 39%; even after 72 h, a signicant reduc-
tion of 34% was observed (26). Therefore, when high doses of
-carotene and canthaxanthin are ingested together, one
should expect a reduction of canthaxanthin absorption.
Another dietary supplement study compared the plasma
appearance of both
-carotene and canthaxanthin in nine
normolipidemic premenopausal women (27). Each subject in-
gested individual doses of 25 mg canthaxanthin or
as well as a combined dose of 25 mg each. Plasma
had a small plasma peak appearance at 5 h, most likely the
chylomicron peak, and then a sustained serum concentration
peak from 24 to 48 h. The appearance of canthaxanthin in the
plasma was monophasic, with a rapid increase at 12 h and a
steady decrease at 24 h. The combined dose of
-carotene and
canthaxanthin reduced the level of canthaxanthin in the
VLDL subfraction (P0.05) but did not signicantly reduce
its appearance in LDL. There was an insignicant change in
the appearance of
-carotene in both plasma and plasma
lipoproteins (27). Therefore, both studies demonstrated a re-
duction of canthaxanthin absorption when consumed concur-
rently with
The relative bioavailability of carotenes compared with the
oxycarotenoids was studied from a natural carotenoid supple-
ment Betatene, which is derived from Dunaliella salina (0.5%
lutein, 0.75% zeaxanthin, 3.6%
-carotene, 70.3% all trans
-carotene, 22.7% cis isomers and 2.1% unidentied carote-
noids). A single dose of 5.6
mol total carotenoids/kg body wt
was given to eight healthy subjects (5 men and 3 women) with
500 mL milk (3.5% fat). Both lutein and zeaxanthin were
taken up from the intestinal lumen into chylomicrons more
efciently than
-carotene and
-carotene from the same
supplement. The content of lutein and zeaxanthin in the
chylomicron were 14- and 4-fold greater, respectively, relative
to Betatene composition, whereas relative composition of
-carotene in the chylomicron was substantially lower than
Betatene (28). Although some of the
- and
-carotene may
have been converted to vitamin A in the enterocyte, this
study suggests that luteins relative bioavailability is greater
than that of
-carotene. Lutein may be more easily incorpo-
rated into the micelle because it is more polar than
- and
-carotene and as such may be incorporated into the polar
exterior of the micelle. In the same regard, the membranes of
enterocytes may take up lutein more readily, which will in-
crease bioavailability (10,28).
Kostic et al. (29) investigated the interaction between
-carotene and lutein during intestinal absorption, metabo-
lism and serum clearance. Four men and four women were
each assigned to one of three groups. Group one was admin-
istered a combined dose, then a single dose of lutein and nally
a single dose of
-carotene. Group 2 received
-carotene, the
combined dose and then a single dose of lutein, whereas group
3 ingested doses in the following order: lutein,
-carotene and
a combined dose. Each phase lasted 5 wk plus 10-d washout
periods. Each subject ingested 0.5
mol/kg body wt of either
-carotene or lutein in oil (0.16 and 0.13 mL oil/kg body wt,
respectively) or both carotenoids in a combined dose in 0.24
mL oil/kg body wt. The mean serum appearance of lutein was
monophasic and had a peak at 16 h; in contrast, the serum
appearance of
-carotene peaked at 6 h and again at 32 h. As
found for canthaxanthin, the consumption of the combined
dose of
-carotene and lutein reduced the absorption of lutein.
However, it was also shown that lutein inuenced
absorption depending on the area under the plasma appear-
ance curve (AUC) values of individuals receiving
alone. Lutein enhanced absorption of
-carotene when the
AUC values of individually dosed
-carotene was 13 (
h)/L. Lutein reduced absorption of
-carotene when sub-
jects AUC values of individual
-carotene doses were 25
mol h)/L (29). Thus it is clear that carotenoids can
interact with each other during intestinal absorption, metab-
olism and serum clearance, and individual responses may vary
markedly. The ability of an individual to convert
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to vitamin A when consuming lutein supplements warrants
further study.
Food processing also affects carotenoid bioavailability. Cas-
tenmiller et al. (30) studied the effects of food processing on
the relative bioavailability of
-carotene and lutein from spin-
ach compared with supplemental sources in humans. In this
study, spinach was consumed in the minced, whole-leaf, liq-
ueed (enzymatically digested) or liqueed with added ber
form. The supplemental standards were
-carotene (vegetable
oil with microcrystalline
-carotene) or lutein plus zeaxanthin
(marigold source) primarily in diester form. Carotenoid sup-
plements were added to the control diet. The percentage of
relative bioavailability of
-carotene from spinach ranged from
5.19%, whereas for lutein it ranged from 45 to 55%. In both
cases, the whole leaf proved to have the lowest percentage of
bioavailability of lutein or
-carotene; the liqueed form had
the highest (30). It can be concluded from this study that
spinach xanthophylls are more bioavailable than
and that food processing improves the relative bioavailability
-carotene more than it does lutein and zeaxanthin.
In conclusion, the xanthophylls, lutein and zeaxanthin
have specic distribution patterns in human tissue especially
in the retina of the eye. The presence of these xanthophylls is
thought to provide protection from macular degeneration. As
this review has shown, the complexity of the bioavailability of
these compounds is far from fully understood. Environmental
factors, food processing, food matrix, structural differences and
the interaction among other food components all have an
effect on their efciency of uptake and absorption.
From the limited human studies, lutein appears to be more
bioavailable from food sources than does
-carotene. The
disruption of the food matrix seems to improve
bioavailability more than that of lutein. There is no evidence
that a negative interaction between carotenoids occurs when
foods are ingesting. However, interactions do occur between
xanthophylls and carotenes when supplements are consumed.
Several studies found that when they were consumed simul-
-carotene reduced lutein bioavailability. With the
broad consumption of lutein supplements from marigold ow-
ers, some of which are high in lutein diesters, the question of
lutein diester bioavailability arises. More dietary fat seems to
be required for efcient absorption of lutein from lutein diester
The current research on xanthophyll bioavailability is lim-
ited and inconsistent. Knowledge is lacking on the bioavail-
ability of xanthophylls other than lutein. More work should be
carried out to compare the bioavailability of free xanthophylls
to mono- and diester forms and to carotenes. More research
should be performed using similar levels of xanthophylls from
foods and supplements. It is also important to understand more
fully the effect of food processing techniques on the bioavail-
ability of xanthophylls. More complete work on the kinetics of
absorption, transport, and turnover and tissue uptake of xan-
thophylls, especially in the eye, is greatly needed.
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... Prawidłowe wchłanianie karotenoidów ma miejsce wyłącznie w obecności kwasów tłuszczowych i soli żółciowych ze względu na lipofilowy charakter tych związków. Skuteczność suplementacji tymi związkami zależy zatem w dużym stopniu od zapewnienia precyzyjnych wytycznych dotyczących spożywania odpowiedniej dawki karotenoidów wraz z posiłkiem zawierającym tłuszcz, który sprzyja włączeniu ich do miceli i ułatwia późniejsze wchłanianie [11,20,34]. Wiele suplementów diety występuje w formie kapsułek, gdyż wchłaniają się lepiej, jeśli są zawieszone w mieszaninie różnych kwasów tłuszczowych. ...
... z białkami lub substytutami tłuszczu, które obniżają wchłanianie karotenoidów. Wiek wydaje się być kolejnym czynnikiem przyczyniającym się do gorszej biodostępności karotenoidów [13,14,25,34]. ...
Luteina, zeaksantyna i astaksantyna zaliczane są do ksantofili, czyli hydroksylowych pochodnych karotenów – związków o silnych właściwościach prozdrowotnych. Wpływają one na prawidłowe funkcjonowanie wielu układów i narządów. Z uwagi na brak możliwości syntetyzowania wymienionych ksantofili przez organizm człowieka oraz stosunkowo małe ich spożycie z żywnością powstaje coraz szersza gama suplementów umożliwiających uzupełnianie niedoborów tych związków. Celem pracy był przegląd suplementów diety zawierających luteinę, zeaksantynę oraz astaksantynę, dostępnych od 5 lipca do 31 października 2019 roku na polskim rynku. Charakterystykę suplementów diety przygotowano na podstawie informacji zamieszczonych na opakowaniach, ulotkach dołączonych do tych opakowań, jak również znajdujących się na stronach internetowych aptek, sklepów zielarskich i sklepów z odżywkami. W badanym okresie stwierdzono obecność 233 takich preparatów, w tym 72 z luteiną, 2 z zeaksantyną, 42 z astaksantyną, 105 z luteiną i zeaksantyną, 6 z luteiną i astaksantyną oraz 6 zawierających wszystkie 3 karotenoidy. Zawartość omawianych związków w zalecanej dziennej dawce zależała przede wszystkim od wskazań do stosowania tych preparatów i wahała się w zakresie 0,02 ÷ 40 mg luteiny, 0,032 ÷ 9 mg zeaksantyny oraz 0,005 ÷ 40 mg astaksantyny. Suplementy diety zawierające luteinę (62 % preparatów) i zeaksantynę (84 % preparatów) były przeznaczone do stosowania w celu zapewnienia prawidłowego widzenia. W przypadku preparatów z astaksantyną wskazywano działanie kompleksowe oraz z przeznaczeniem dla osób ze schorzeniami układu sercowo-naczyniowego (po 28 %).
... All of these health benefits are influenced by the zeaxanthin absorption, which is highly dependent on its interactions with other carotenoids (van den Berg, 1999;Zaripheh & Erdman, 2002). Generally, a low food intake of carotenoids may lead to several health problems such as AMD. ...
... Interactions between carotenoids can influence their absorption (van den Berg, 1999;Zaripheh & Erdman, 2002). Thus, in humans, carotenes (β-carotene) decrease the absorption of xanthophylls (White et al., 1994). ...
Background Zeaxanthin is a carotenoid pigment found in several fruits and vegetables. Belonging to the xanthophyll family, it is widely present in human and some animals skin and eyes, performing important physiological functions due to its antioxidant and anti-inflammatory effects. Several studies have explored its health benefits against important disorders such as neurological diseases, allergies, and cancer. Scope and approach The aim of this study we to explore the sources, health benefits, and biological properties of zeaxanthin and analyzes its drug interaction with β-carotene. Key findings and conclusion Severela vegetable sources in particularly fruits parts contains zeaxanthin. Biological investigations showed that zeaxanthin has been found to exhibit a protective effect against excessive light and oxidative stress side effects, preventing the development of several neurological, skin, and eye disorders. It exhibits also antioxidant, antiparasitic, anthelmintic activity, and antiosteoporosis effects. Zeaxanthin can also play a role in the inflammatory response, contributing to the treatment or prevention of diseases like allergies and AIDS. Additionally, zeaxanthin can exhibit anticancer, anti-osteoporotic, and ophthalmologic effects. These different properties are mediated by diffetent cellular and molecular mechanisms exhibited by zeaxanthin such as its activation and/or blocker of cell receptors, its actions on signaling pathways, and also its effects on gene expression. Moreover, the safety as a dietary supplement has also been confirmed and its interaction with other carotenoids, such as β-carotene, has been studied and validated in pharmacokinetic investigations. However, further investigations are needed to explore the full potential of zeaxanthin and to elucidate more its molecular pharmacodynamic actions behind its effects on human health, and to investigate also its clinical applications.
... Pressure rise led to the significant increase of chlorophyll ( Figure 1c) and carotenoid content (Figure 1d,e) as well as the remarkable improvement of the extract's antioxidant activity (Figure 1f). The extraction of more polar carotenoids, such as lutein and astaxanthin [35], was justifiably enhanced by the pressure increase that also favored the polarity of supercritical CO 2 [31]. A milder increase of extraction yield and phenolics was also noted ( Figure 1c). ...
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Microalgae are well-known for their high-added value compounds and their recovery is currently of great interest. The aim of this work is the recovery of such components from Chlorella vulgaris through supercritical fluid extraction (SFE) with CO2. The effect of the extraction temperature (40–60 °C), pressure (110–250 bar), and solvent flow rate (20–40 g/min) was tested on yield, the extract’s antioxidant activity, and the phenolic, chlorophyll and carotenoid content. Thus, data analysis indicated that the yield was mainly affected by temperature, carotenoids by pressure, while the extract’s phenolics and antioxidant activity were affected by the synergy of temperature and pressure. Moreover, SFE’s kinetic study was performed and experimental data were correlated using Sovová’s mass transfer-based model. SFE optimization (60 °C, 250 bar, 40 g/min) led to 3.37% w/w yield, 44.35 mgextr/mgDPPH antioxidant activity (IC50), 18.29 mgGA/gextr total phenolic content, 35.55, 21.14 and 10.00 mg/gextr total chlorophyll, carotenoid and selected carotenoid content (astaxanthin, lutein and β-carotene), respectively. A comparison of SFE with conventional aq. ethanol (90% v/v) extraction proved SFE’s superiority regarding extraction duration, carotenoids, antioxidant activity and organoleptic characteristics of color and odor despite the lower yield. Finally, cosolvent addition (ethanol 10% w/w) at optimum SFE conditions improved the extract’s antioxidant activity (19.46%) as well as yield (101.81%).
... Carotenoids are accessory photosynthetics pigment molecules that cover visible spectrum light absorption not utilized by Chls, while xanthophylls and lutein have higher bioaccessibility when carotenes concentration is low(Zaripheh and Erdman 2002), and forms major Cars that accumulate in young leaves under shade or low light conditions of the in vitro culture(Yoon et al. 2012). They can be synthesized during unfavourable growth condition for the scavenging of free radicals, and as lightharvesting pigment quenchers of Chl state, and singlet O 2 species among other functions (Safafar et al. ...
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Rauvolfia serpentina (L) Benth ex Kurz is an endangered medicinal woody species, widely distributed in Asia and used in several traditional medicine systems. Application of in vitro clonal propagation offers alternative strategies for biomass production useful in the production of pharmaceuticals but, difficulty in explant selection and low response to clonal production are impediment to the success. The present study evaluated efficiency of in vitro rejuvenation of nodal segment explants derived from basal offshoots and terminal buds collected across growth seasons and effect of serial subcultures on shoot morphogenesis in R. serpentina . Effect of culture medium strength (quarter, half and full strength MS) on shoot morphogenesis and proliferation through four (4) subcultures were also evaluated. Of the PGRs tested, BAP was more efficient over Kin and TDZ, and addition of NAA (0.5 mg L − 1 ) to the PGRs promoted shoot morphogenesis. Rhizogenesis was achieved using half basal MS medium added with IBA, NAA and IAA with IBA been the most efficient over other auxins tested. However, lower concentration of the IBA showed most appropriate results on good root differentiation. As a result, IBA has been the most efficient over other auxins tested but, lower concentration is the most appropriate for good root differentiation. Differential accumulation of pigment molecules and cellular osmolytes in response to the culture condition were evaluated in the dark-green and pale-green leaf morpho-types observed in the shoot cultures. Results of the present experiment suggests that explants collection season and PGRs influenced in vitro rejuvenation of nodal segment explants through physiological and biochemical changes essential for shoot morphogenesis.
... They must be moved to bulk lipids or intestinal micelles in the digesta because they are hydrophobic (Faulks and Southon, 2005). The presence of dietary fat in the small intestine, which promotes the release of emulsifying bile acids by the gallbladder, is needed for carotenoids absorption (Zaripheh and Erdman, 2002). Recent research has found that when carotenoids are consumed with dietary lipids, their absorption increases (Brown et al., 2004). ...
Carotenoids are widely distributed among naturally occurring plant pigments, with a high degree of structural variability and a broad range of biological functions. Because of their capacity to quench singlet oxygen and scavenge free radicals, they have antioxidant properties. Carotenoids have been related to the prevention and treatment of a number of chronic diseases, including certain cancers, cardiovascular diseases, and eye diseases, as well as enhancement of immune system functions.
... The carotenoid family encompasses various pigments used in the light-harvesting reactions of photosynthesis, and are known to serve as antioxidants that quench triplet chlorophyll ( 3 Chl*), an excited state of chlorophyll, as well as its toxic product, singlet oxygen ( 1 O 2 ), which is formed when 3 Chl* reacts with oxygen, while also stabilizing the phospholipid bilayer in the thylakoid membrane of chloroplasts (Boucher et al., 1977;Croce et al., 1999;Demmig-Adams and Adams, 1996;Foote et al., 1970;Havaux, 1998). Carotenoids can be subcategorized as either carotenes or xanthophylls, depending on their molecular structure and where they are located in the chloroplast (Zaripheh and Erdman, 2002). More specifically, carotenes are localized in the core complexes of photosystems I and II, whereas xanthophylls are predominantly bound to the light-harvesting complexes of chloroplasts, where they scavenge ROS to protect plants against oxidative stress (Croce et al., 1999;Qin et al., 2015;Su et al., 2017;Umena et al., 2011). ...
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Heat-induced leaf senescence has been associated with stress-induced oxidative damage. The major objective of this study was to determine whether exogenous application of β-carotene may improve heat tolerance in creeping bentgrass ( Agrostis stolonifera cv. Penncross) by suppressing leaf senescence and activating antioxidant metabolism. Plants were subjected to heat stress at 35/30 °C (day/night) or at the optimal temperature of 22/18 °C (day/night), and were treated with either β-carotene (1 m m ) or water (untreated control) by foliar spraying every 7 days for 28 days in controlled-environment growth chambers. β-Carotene application suppressed heat-induced leaf senescence, as demonstrated by an increase in turf quality (TQ) and leaf chlorophyll content as well as a reduction in electrolyte leakage (EL). β-Carotene-treated plants had a significantly lower malondialdehyde (MDA) content and significantly greater activity of antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) from 14 through 28 days of heat stress, and ascorbate peroxidase (APX) activity from 21 through 28 days of heat stress. These findings suggest that β-carotene may promote heat tolerance by enhancing antioxidant activity to suppress leaf senescence.
... It involves four major events: release of the xanthophylls from the food matrix, transfer of the released particles to lipid micelles in the small intestine (facilitated by dietary fat intake and biliary secretions), uptake by the intestinal cells via passive diffusion, and transportation to the lymphatic system. 26,27 Roodenburg and colleagues 28 reported that more than 3 g of fat was required to enhance the solubility of lutein diesters and facilitate pancreatic secretions of lipases and esterases. Lutein diesters being hydrophobic requires fat and hydrolysis by pancreatic enzymes to make them soluble. ...
... It involves four major events: release of the xanthophylls from the food matrix, transfer of the released particles to lipid micelles in the small intestine (facilitated by dietary fat intake and biliary secretions), uptake by the intestinal cells via passive diffusion, and transportation to the lymphatic system. 26,27 Roodenburg and colleagues 28 reported that more than 3 g of fat was required to enhance the solubility of lutein diesters and facilitate pancreatic secretions of lipases and esterases. Lutein diesters being hydrophobic requires fat and hydrolysis by pancreatic enzymes to make them soluble. ...
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Age-related macular degeneration (ARMD) is one of the prominent causes of central visual loss in the older age group in the urbanized, industrialized world. In recent years, many epidemiological studies and clinical trials have evaluated the role of antioxidants and micronutrients to prevent the progression of ARMD. In this article, we review some of these major studies. In addition, we review the absorption and bioavailability and possible undesirable effects of these nutrients after ingestion. The role of genotypes and inappropriate use of these supplements are also discussed. From all the above evidence, we conclude that it may not be prudent to prescribe these formulations without a proper assessment of the individual’s health and dietary status. The effectiveness of all the components in antioxidant formulations is controversial. Thus, these supplements should not be prescribed just for the purpose of providing patients some kind of therapy, which may give a false sense of mental satisfaction.
A bioprospecting study was conducted from Seawater samples collected at Kaohsiung Seacoast, Taiwan. The current research was aimed to isolate potential lutein-producing strain, evaluate and optimize the best cultivation mode, lutein accumulation stage, lutein-extraction method, and condition to recover maximum lutein (main product) and lipid (byproduct). Biorefinery is the latest approach worldwide to extract multi-products for cost-effectiveness. Selected isolate among several isolates, identified as Chlorella sorokiniana Kh12 and exploited under biorefinery concept for lutein and lipid extraction. Kh12 cultivated under mixotrophy: 2X-(HT)-9k yielded maximum biomass (3.46 g L⁻¹) and lutein (13.69 mg g⁻¹) which is among the higher yields reported so far. Among various tested solvents, methanol was the best extractor. Bead milling was most effective to disrupt algal cell walls, seven minutes of milling was best for maximum lutein (7.56 mg g⁻¹) extraction. Kh12 could be a promising candidate for commercial lutein and lipid co-production based on the outcome.
Lutein is a nutraceutical compound that promotes human eye health and prevents neurodegenerative diseases. The oral bioavailability of lutein is affected by both extrinsic and intrinsic factors in the host. Although hydrophobicity of the compound is further challenging, its lipophilicity can be utilized to micellize and thereby improve its oral bioavailability. Currently, available data on the effects of dietary fats on lutein micellization and permeation is limited and needs further exploration. In this study, the influence of 17 carrier type edible oils on lutein micellization and permeation, was investigated in a simulated digestion model. The overall effectiveness of these oils to permeate micellized lutein was attributed to its Fatty Acid (FA) profile. While 94% of the edible oils exhibited a positive influence on the permeation of micellized lutein, the micellization and permeation efficiency of these oils were significantly (p ≤ 0.05) modulated by the saturation of FA in the order Saturated (SFA) > Mono-Unsaturated (MUFA) > Poly-Unsaturated (PUFA). The highest apparent permeability coefficient was exhibited by lutein micellized in ghee (3.01 × 10⁻⁶ cm/s) and butter (2.93 × 10⁻⁶ cm/s), which was 1.28 and 1.24 folds higher than lutein alone (2.35 × 10⁻⁶ cm/s) respectively. Exceptionally MUFA rich olive oil and PUFA rich flaxseed oil improved lutein permeation by 1.19 (2.80 × 10⁻⁶ cm/s) and 1.14 folds (2.69 × 10⁻⁶ cm/s) respectively. This study is the first to report the influence of saturated fatty acids on micellization and permeation of lutein. Furthermore, the outcomes of this study offer the field of lutein delivery systems a fresh perspective.
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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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Carotenoids are purported to provide widespread function in the biology and health of humans and other mammalian species. Provitamin A carotenoids, such as b-carotene, are valued in the diet of many mammals for their contribution as precursors of vitamin A and retinoids. Carotenoids may also function in the prevention of some chronic diseases by improving intercellular communication. enhancing immune response, and operating as antioxidants in vivo. It is widely known that humans and other mammalian species absorb and accumulate carotenoids in body tissues. However, the potential use of carotenoids as modulators of disease and in the prevention of vitamin A de®ciency has been hindered by the limited progress in understanding carotenoid absorption and metabolism. In fact, major gaps in knowledge still exist in the fundamental pathways beginning with release from the food matrix and ending with distribution in body tissues and excretion. Continued development of assessment methods for humans, appropriate animal models for mechanistic studies, and analytical techniques for quanti®cation and identi®cation of compounds is needed to advance our understanding of these critical pathways. This review will discuss the current knowledge involving the fundamental pathways of absorption and metabolism of carotenoids in mamma-lian species. When applicable, emphasis will be placed on the human.
A double-blind, placebo-controlled crossover study of the effects of the nonabsorbable fat analogue sucrose polyester (SPE; 12.4 g/d) on plasma concentrations of five different carotenoids and vitamin E in 21 volunteers, and a double-blind, placebo-controlled parallel comparison study in 53 subjects of the effect of 3 g SPE/d on plasma concentrations of two different carotenoids were undertaken. SPE-containing margarine added to the main meal was used. SPE (12.4 g/d) reduced plasma of beta-carotene concentrations by 0.13 mumol/L (34%, P = 0.0001) and concentrations of lycopene by 0.14 mumol/L (52%, P = 0.0001). Smaller but significant reductions were found for plasma concentrations of beta-cryptoxanthin, lutein, zeaxanthin, and vitamin E. SPE (3 g/d) reduced plasma concentrations of beta-carotene by 0.094 mumol/L (20% P = 0.0001) and concentrations of lycopene by 0.12 mumol/L (38%, P = 0.0001). Even at low doses, SPE strongly reduces plasma carotenoid concentrations. This finding merits careful consideration in assessing the long-term health effects of SPE-containing consumer foods.
This chapter describes a stable isotope tracer method based on the use of highly enriched β-[U-13C]carotene and high-precision isotope ratio mass spectrometry (IRMS). Biological applications of IRMS are reviewed in the chapter. In gas chromatography combustion (GCC)–IRMS, combusted analytes are detected as the CO2+ produced in a high-sensitivity tight ion source. Each carbon atom of the analyte molecule has an independent chance of ionization and therefore detection limits are related to moles of analyte carbon, rather than to moles of analyte as in gas chromatography/mass chromatography (GC/MS). The ionization probability and molecular ion stability of CO2 is constant for all analytes. For these reasons, compounds of low ionization efficiency, low stability, and high molecular weight tend to be detected with high sensitivity by GCC–IRMS compared to conventional organic GC/MS. GCC–IRMS permits use of low doses typical of daily β-carotene intake, which do not perturb endogenous pool sizes of β-carotene or retinol. β-[13C]carotene is clearly evident in plasma by 3 hr after a dose of 2 mg β-[U-13C]carotene. In contrast, no detectable increase in concentration of labeled βC could be observed prior to 5 hr postdose with 40 mg β-carotene-d8 uring organic mass spectrometry.
The fabrication and characteristics of a humidity sensor using a porous polymer layer are presented. To generate cracks on the sensor structure, we deposited the upper electrode in a state of tensile stress using e-beam evaporation. The width and size of the crack were increased with the thickness of the upper electrode. The sensitivity of the sensor in the 10–90% r.h. range is 0.2 pF/% r.h., increasing with the increase of relative humidity and its hysteresis was about 3% r.h. at 50% r.h..
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A diet rich in carotenoid-containing foods is associated with a number of health benefits. Lycopene provides the familiar red color to tomato products and is one of the major carotenoids in the diet of North Americans and Europeans. Interest in lycopene is growing rapidly following the recent publication of epidemiologic studies implicating lycopene in the prevention of cardiovascular disease and cancers of the prostate or gastrointestinal tract. Lycopene has unique structural and chemical features that may contribute to specific biological properties. Data concerning lycopene bioavailability, tissue distribution, metabolism, excretion, and biological actions in experimental animals and humans are beginning to accumulate although much additional research is necessary. This review will summarize our knowledge in these areas as well as the associations between lycopene consumption and human health.
Carotenoid bioavailability depends, amongst other factors, on the food matrix and on the type and extent of processing. To examine the effect of variously processed spinach products and of dietary fiber on serum carotenoid concentrations, subjects received, over a 3-wk period, a control diet (n = 10) or a control diet supplemented with carotenoids or one of four spinach products (n = 12 per group): whole leaf spinach with an almost intact food matrix, minced spinach with the matrix partially disrupted, enzymatically liquefied Spinach in which the matrix was further disrupted and the liquefied spinach to which dietary fiber (10 g/kg wet weight) was added. Consumption of spinach significantly increased serum concentrations of all-trans-β- carotene, cis-β-carotene, (and consequently total β-carotene), lutein, α- carotene and retinol and decreased the serum concentration of lycopene. Serum total β-carotene responses (changes in serum concentrations from the start to the end of the intervention period) differed significantly between the whole leaf and liquefied spinach groups and between the minced and liquefied spinach groups. The lutein response did not differ among spinach groups. Addition of dietary fiber to the liquefied spinach had no effect on serum carotenoid responses. The relative bioavailability as compared to bioavailability of the carotenoid supplement for whole leaf, minced, liquefied and liquefied spinach plus added dietary fiber for β-carotene was 5.1, 6.4, 9.5 and 9.3%, respectively, and for lutein 45, 52, 55 and 54%, respectively. We conclude that the bioavailability of lutein from spinach was higher than that of β-carotene and that enzymatic disruption of the matrix (cell wall structure) enhanced the bioavailability of β-carotene from whole leaf and minced spinach, but had no effect on lutein bioavailability.