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A. R. C. Braga and V. V. de Rosso
however, they were instructed not to take vitamin supplement tablets, drink nutritional
supplements, or drink vegetable juice during the study, because these products potentially contain large amounts of lutein. Before ingestion of the CP tablets, subjects
(n = 21) were divided into three groups based on initial serum lutein levels, BMI,
and age. A fasting blood sample was collected in the morning (08:00 to 09:00) at
–7, 0, 1, 2, and 3 d. On the morning of 0 d, after the blood sampling, each subject
took a single CP dose (0, 3, or 6 g) in tablet form with bread (40 g), olive oil (10 g),
and water (280 mL). During the experiment, the subjects kept food diaries regarding
their consumption of vegetables, fruits, and eggs to allow estimation of their dietary
intake of lutein. The carotenoid content of the foods was estimated from data by the
USDA National Nutrient Database for Standard Reference. The carotenoid content
of the 3 and 6 g tablets was (respectively): 8.6 and 17.3 mg of lutein, 1.3 and 2.6 mg
of α-carotene, and 2.1 and 4.2 mg of β-carotene. For the analysis of serum carotenoid
concentrations, blood samples (5 to 10 mL) were drawn from a forearm vein, and
serum was separated from the blood cells by centrifugation. At 1 d, serum lutein
concentrations increased from baseline values by 34% (25.6 nM/mg-lutein intake)
after 3 g CP and by 66% (21.4 nM/mg-lutein intake) after 6 g CP. These results
suggest that lutein in CP is highly bioavailable.
10.5 Conclusion
To date, studies aimed at determining the bioaccessibility and bioavailability of
pigments from microalgae are very restricted. It is necessary to apply more modern
methods, such as the harmonized method by INFOGEST, in order to compare results
obtained in different laboratories. On the other hand, it can already be seen that the
microalgae cell wall is an important barrier for enzymatic digestion, resulting in poor
bioaccessibility and consequently bioavailability of carotenoids. For applications in
food products and food supplements, it is suggested to apply a technology to break
down the cell wall and facilitate the digestion and utilization of these compounds.
References
Asai, A., Yonekura, L., & Nagao, A. (2008). Low bioavailability of dietary epoxyxanthophylls in
humans. British Journal of Nutrition, 100, 273–277.
Begum, H., Yusoff, F. M. D., Banerjee, S., Khatoon, H., & Shariff, M. (2016). Availability and
utilization of pigments from microalgae. Critical Reviews in Food Science and Nutrition, 56,
2209–2222.
Brown, E. M., Nitecki, S., Pereira-Caro, G., McDougall, G. J., Stewart, D., Rowland, I., et al.
(2014). Comparison of in vivo and in vitro digestion on polyphenol composition in lingonberries:
Potential impact on colonic health. BioFactors, 406, 611–623.
A. R. C. Braga and V. V. de Rosso
however, they were instructed not to take vitamin supplement tablets, drink nutritional
supplements, or drink vegetable juice during the study, because these products potentially contain large amounts of lutein. Before ingestion of the CP tablets, subjects
(n = 21) were divided into three groups based on initial serum lutein levels, BMI,
and age. A fasting blood sample was collected in the morning (08:00 to 09:00) at
–7, 0, 1, 2, and 3 d. On the morning of 0 d, after the blood sampling, each subject
took a single CP dose (0, 3, or 6 g) in tablet form with bread (40 g), olive oil (10 g),
and water (280 mL). During the experiment, the subjects kept food diaries regarding
their consumption of vegetables, fruits, and eggs to allow estimation of their dietary
intake of lutein. The carotenoid content of the foods was estimated from data by the
USDA National Nutrient Database for Standard Reference. The carotenoid content
of the 3 and 6 g tablets was (respectively): 8.6 and 17.3 mg of lutein, 1.3 and 2.6 mg
of α-carotene, and 2.1 and 4.2 mg of β-carotene. For the analysis of serum carotenoid
concentrations, blood samples (5 to 10 mL) were drawn from a forearm vein, and
serum was separated from the blood cells by centrifugation. At 1 d, serum lutein
concentrations increased from baseline values by 34% (25.6 nM/mg-lutein intake)
after 3 g CP and by 66% (21.4 nM/mg-lutein intake) after 6 g CP. These results
suggest that lutein in CP is highly bioavailable.
10.5 Conclusion
To date, studies aimed at determining the bioaccessibility and bioavailability of
pigments from microalgae are very restricted. It is necessary to apply more modern
methods, such as the harmonized method by INFOGEST, in order to compare results
obtained in different laboratories. On the other hand, it can already be seen that the
microalgae cell wall is an important barrier for enzymatic digestion, resulting in poor
bioaccessibility and consequently bioavailability of carotenoids. For applications in
food products and food supplements, it is suggested to apply a technology to break
down the cell wall and facilitate the digestion and utilization of these compounds.
References
Asai, A., Yonekura, L., & Nagao, A. (2008). Low bioavailability of dietary epoxyxanthophylls in
humans. British Journal of Nutrition, 100, 273–277.
Begum, H., Yusoff, F. M. D., Banerjee, S., Khatoon, H., & Shariff, M. (2016). Availability and
utilization of pigments from microalgae. Critical Reviews in Food Science and Nutrition, 56,
2209–2222.
Brown, E. M., Nitecki, S., Pereira-Caro, G., McDougall, G. J., Stewart, D., Rowland, I., et al.
(2014). Comparison of in vivo and in vitro digestion on polyphenol composition in lingonberries:
Potential impact on colonic health. BioFactors, 406, 611–623.