Carotenoids

A special issue of Antioxidants (ISSN 2076-3921). This special issue belongs to the section "Natural and Synthetic Antioxidants".

Deadline for manuscript submissions: closed (30 June 2019) | Viewed by 75462

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Guest Editor
Institute of Nutritional Sciences, Friedrich Schiller University Jena, Dornburger Straße 25-29, 07743 Jena, Germany
Interests: dietary antioxidants; carotenoids; polyphenols; vitamin E; vitamin C; antioxidant activity/capacity; interactions; bioavailability
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Special Issue Information

Dear Colleagues,

The purpose of this Special Issue of Antioxidants is to present recent investigations on the role of carotenoids as antioxidants in health promotion and disease prevention as well as results on the non-antioxidant activities of carotenoids. As the biological activities can only be exerted when the compounds are absorbed, the in vitro bioaccessibility and the in vivo intestinal uptake of carotenoids are important aspects to examine. It is also of interest to describe the recent developments in the structural characterization of the bioactive, endogenous metabolites of carotenoids and in the use of carotenoids in the industry.

Carotenoids are a group of natural pigments, consisting of more than 750 compounds. Their colours are mostly yellow, orange, and red and are due to the system of conjugated double bonds that they contain. This structural element is also responsible for the antioxidant properties of many carotenoids. Carotenoids have shown various biological activities (not only as provitamin A) and are, therefore, an interesting subject for researchers of various disciplines all over the world, investigating, for instance, the disease preventive properties of fruits and vegetables. As lipophilic compounds, their uptake and storage in the body is dependent on various factors. In vitro and in vivo data showed both enhancing and inhibiting effects of matrix constituents on the bioaccessibility and bioavailability of carotenoids.

I invite you to submit original research papers or review articles focusing on all issues related to carotenoids.

Prof. Dr. Volker Böhm
Guest Editor

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Keywords

  • Carotenoids
  • Absorption, metabolism, and bioavailability
  • Pharmacokinetics
  • Antioxidant mechanisms
  • Non-antioxidant activities
  • Health and disease
  • Industrial uses
  • Functional properties
  • Extraction and chemical characterization of metabolites

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Published Papers (12 papers)

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Editorial

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2 pages, 156 KiB  
Editorial
Carotenoids
by Volker Böhm
Antioxidants 2019, 8(11), 516; https://doi.org/10.3390/antiox8110516 - 29 Oct 2019
Cited by 6 | Viewed by 2707
Abstract
Carotenoids are a group of natural pigments, consisting of more than 750 compounds known so far [...] Full article
(This article belongs to the Special Issue Carotenoids)

Research

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13 pages, 1874 KiB  
Article
Inclusion Complexes of Lycopene and β-Cyclodextrin: Preparation, Characterization, Stability and Antioxidant Activity
by Haixiang Wang, Shaofeng Wang, Hua Zhu, Suilou Wang and Jiudong Xing
Antioxidants 2019, 8(8), 314; https://doi.org/10.3390/antiox8080314 - 16 Aug 2019
Cited by 33 | Viewed by 4581
Abstract
In this study, the inclusion complexes of lycopene with β-cyclodextrin (β-CD) were prepared by the precipitation method. Then the inclusion complexes were characterized by the scanning electron microscopy (SEM), ultraviolet-visible spectroscopy (UV), microscopic observation, liquid chromatography, differential scanning calorimetry (DSC) and phase-solubility study. [...] Read more.
In this study, the inclusion complexes of lycopene with β-cyclodextrin (β-CD) were prepared by the precipitation method. Then the inclusion complexes were characterized by the scanning electron microscopy (SEM), ultraviolet-visible spectroscopy (UV), microscopic observation, liquid chromatography, differential scanning calorimetry (DSC) and phase-solubility study. Moreover, the stability and antioxidant activity were tested. The results showed that lycopene was embedded into the cavity of β-CD with a 1:1 stoichiometry. Moreover, the thermal and irradiant stabilities of lycopene were all significantly increased by the formation of lycopene/β-CD inclusion complexes. Antioxidant properties of lycopene and its inclusion complexes were evaluated on the basis of measuring the scavenging activity for 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl and superoxide anion radicals. The results showed that the scavenging activity of DPPH radicals was obviously increased by the formation of the inclusion complex with β-cyclodextrin at concentrations of 5–30 μg/mL, however, some significant positive effects on the scavenging activity of hydroxyl and superoxide anion radicals were not observed and the reasons are worth further study. Full article
(This article belongs to the Special Issue Carotenoids)
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11 pages, 1137 KiB  
Article
In Vitro Digestion of Human Milk: Influence of the Lactation Stage on the Micellar Carotenoids Content
by Ana A. O. Xavier, Juan E. Garrido-López, Josefa Aguayo-Maldonado, Juan Garrido-Fernández, Javier Fontecha and Antonio Pérez-Gálvez
Antioxidants 2019, 8(8), 291; https://doi.org/10.3390/antiox8080291 - 07 Aug 2019
Cited by 9 | Viewed by 3033
Abstract
Human milk is a complex fluid with nutritive and non-nutritive functions specifically structured to cover the needs of the newborn. The present study started with the study of carotenoid composition during progress of lactation (colostrum, collected at 3–5 d postpartum; mature milk, collected [...] Read more.
Human milk is a complex fluid with nutritive and non-nutritive functions specifically structured to cover the needs of the newborn. The present study started with the study of carotenoid composition during progress of lactation (colostrum, collected at 3–5 d postpartum; mature milk, collected at 30 d postpartum) with samples donated from full-term lactating mothers (women with no chronic diseases, nonsmokers on a regular diet without supplements, n = 30). Subsequently, we applied an in vitro protocol to determine the micellarization efficiency of the carotenoids, which were separated by HPLC and quantified by the external standard method. That in vitro protocol is tailored for the biochemistry of the digestive tract of a newborn. To the best of our knowledge, the present study is the first report of carotenoids micellar contents, obtained in vitro. This study reveals, from the in vitro perspective, that colostrum and mature milk produce significant micellar contents of carotenoids despite lipids in milk are within highly complex structures. Indeed, the lactation period develops some influence on the micellarization efficiency, influence that might be attributed to the dynamics of the milk fat globule membrane (MFGM) during the progress of lactation. Full article
(This article belongs to the Special Issue Carotenoids)
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17 pages, 3769 KiB  
Article
Lycopene Modulates Pathophysiological Processes of Non-Alcoholic Fatty Liver Disease in Obese Rats
by Mariane Róvero Costa, Jéssica Leite Garcia, Carol Cristina Vágula de Almeida Silva, Artur Junio Togneri Ferron, Fabiane Valentini Francisqueti-Ferron, Fabiana Kurokawa Hasimoto, Cristina Schmitt Gregolin, Dijon Henrique Salomé de Campos, Cleverton Roberto de Andrade, Ana Lúcia dos Anjos Ferreira, Camila Renata Corrêa and Fernando Moreto
Antioxidants 2019, 8(8), 276; https://doi.org/10.3390/antiox8080276 - 05 Aug 2019
Cited by 42 | Viewed by 6277
Abstract
Background: The higher consumption of fat and sugar are associated with obesity development and its related diseases such as non-alcoholic fatty liver disease (NAFLD). Lycopene is an antioxidant whose protective potential on fatty liver degeneration has been investigated. The aim of this [...] Read more.
Background: The higher consumption of fat and sugar are associated with obesity development and its related diseases such as non-alcoholic fatty liver disease (NAFLD). Lycopene is an antioxidant whose protective potential on fatty liver degeneration has been investigated. The aim of this study was to present the therapeutic effects of lycopene on NAFLD related to the obesity induced by a hypercaloric diet. Methods: Wistar rats were distributed in two groups: Control (Co, n = 12) and hypercaloric (Ob, n = 12). After 20 weeks, the animals were redistributed into the control group (Co, n = 6), control group supplemented with lycopene (Co+Ly, n = 6), obese group (Ob, n = 6), and obese group supplemented with lycopene (Ob+Ly, n = 6). Ob groups also received water + sucrose (25%). Animals received lycopene solution (10 mg/kg/day) or vehicle (corn oil) via gavage for 10 weeks. Results: Animals which consumed the hypercaloric diet had higher adiposity index, increased fasting blood glucose, hepatic and blood triglycerides, and also presented in the liver macro and microvesicular steatosis, besides elevated levels of tumor necrosis factor-α (TNF-α). Lycopene has shown therapeutic effects on blood and hepatic lipids, increased high-density lipoprotein cholesterol (HDL), mitigated TNF-α, and malondialdehyde (MDA) and further improved the hepatic antioxidant capacity. Conclusion: Lycopene shows therapeutic potential to NAFLD. Full article
(This article belongs to the Special Issue Carotenoids)
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8 pages, 789 KiB  
Article
Fucoxanthin—An Antibacterial Carotenoid
by Tomasz M. Karpiński and Artur Adamczak
Antioxidants 2019, 8(8), 239; https://doi.org/10.3390/antiox8080239 - 24 Jul 2019
Cited by 127 | Viewed by 8031
Abstract
Fucoxanthin is a carotenoid produced by brown algae and diatoms. This compound has several biological properties such as antioxidant, anti-obesity, anti-diabetic, anticancer, and antimicrobial activities. Unfortunately, until now the latter effect has been poorly confirmed. The aim of this study was an evaluation [...] Read more.
Fucoxanthin is a carotenoid produced by brown algae and diatoms. This compound has several biological properties such as antioxidant, anti-obesity, anti-diabetic, anticancer, and antimicrobial activities. Unfortunately, until now the latter effect has been poorly confirmed. The aim of this study was an evaluation of fucoxanthin activity against 20 bacterial species. Antimicrobial effect of fucoxanthin was determined by using the agar disc-diffusion and micro-dilution methods. The studied carotenoid acted against 13 bacteria growing in aerobic conditions. It was observed to have a significantly stronger impact on Gram-positive than Gram-negative bacteria. Mean zones of growth inhibition (ZOIs) for Gram-positive bacteria ranged between 9.0 and 12.2 mm, while for Gram-negative were from 7.2 to 10.2 mm. According to the agar disc-diffusion method, the highest activity of fucoxanthin was exhibited against Streptococcus agalactiae (mean ZOI 12.2 mm), Staphylococcus epidermidis (mean ZOI 11.2 mm), and Staphylococcus aureus (mean ZOI 11.0 mm), and in the microdilution test towards Streptococcus agalactiae with the minimal inhibitory concentration (MIC) of 62.5 µg/mL. On the other hand, fucoxanthin was not active against strict anaerobic bacteria. Full article
(This article belongs to the Special Issue Carotenoids)
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12 pages, 652 KiB  
Article
Preparation of Retinoyl-Flavonolignan Hybrids and Their Antioxidant Properties
by Christopher S. Chambers, David Biedermann, Kateřina Valentová, Lucie Petrásková, Jitka Viktorová, Marek Kuzma and Vladimír Křen
Antioxidants 2019, 8(7), 236; https://doi.org/10.3390/antiox8070236 - 23 Jul 2019
Cited by 12 | Viewed by 3972
Abstract
Antioxidants protect the structural and functional components in organisms against oxidative stress. Most antioxidants are of plant origin as the plants are permanently exposed to oxidative stress (UV radiation, photosynthetic reactions). Both carotenoids and flavonoids are prominent antioxidant and anti-radical agents often occurring [...] Read more.
Antioxidants protect the structural and functional components in organisms against oxidative stress. Most antioxidants are of plant origin as the plants are permanently exposed to oxidative stress (UV radiation, photosynthetic reactions). Both carotenoids and flavonoids are prominent antioxidant and anti-radical agents often occurring together in the plant tissues and acting in lipophilic and hydrophilic milieu, respectively. They are complementary in their anti-radical activity. This study describes the synthesis of a series of hybrid ester conjugates of retinoic acid with various flavonolignans, such as silybin, 2,3-dehydrosilybin and isosilybin. Antioxidant/anti-radical activities and bio-physical properties of novel covalent carotenoid-flavonoid hybrids, as well as various mixtures of the respective parent components, were investigated. Retinoyl conjugates with silybin—which is the most important flavonolignan in silymarin complex—(and its pure diastereomers) displayed better 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity than both the parent compounds and their equimolar mixtures. Full article
(This article belongs to the Special Issue Carotenoids)
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10 pages, 2581 KiB  
Article
First Apocarotenoids Profiling of Four Microalgae Strains
by Mariosimone Zoccali, Daniele Giuffrida, Fabio Salafia, Carmen Socaciu, Kari Skjånes, Paola Dugo and Luigi Mondello
Antioxidants 2019, 8(7), 209; https://doi.org/10.3390/antiox8070209 - 06 Jul 2019
Cited by 16 | Viewed by 4231
Abstract
Both enzymatic or oxidative carotenoids cleavages can often occur in nature and produce a wide range of bioactive apocarotenoids. Considering that no detailed information is available in the literature regarding the occurrence of apocarotenoids in microalgae species, the aim of this study was [...] Read more.
Both enzymatic or oxidative carotenoids cleavages can often occur in nature and produce a wide range of bioactive apocarotenoids. Considering that no detailed information is available in the literature regarding the occurrence of apocarotenoids in microalgae species, the aim of this study was to study the extraction and characterization of apocarotenoids in four different microalgae strains: Chlamydomonas sp. CCMP 2294, Tetraselmis chuii SAG 8-6, Nannochloropsis gaditana CCMP 526, and Chlorella sorokiniana NIVA-CHL 176. This was done for the first time using an online method coupling supercritical fluid extraction and supercritical fluid chromatography tandem mass spectrometry. A total of 29 different apocarotenoids, including various apocarotenoid fatty acid esters, were detected: apo-12’-zeaxanthinal, β-apo-12’-carotenal, apo-12-luteinal, and apo-12’-violaxanthal. These were detected in all the investigated strains together with the two apocarotenoid esters, apo-10’-zeaxanthinal-C4:0 and apo-8’-zeaxanthinal-C8:0. The overall extraction and detection time for the apocarotenoids was less than 10 min, including apocarotenoids esters, with an overall analysis time of less than 20 min. Moreover, preliminary quantitative data showed that the β-apo-8’-carotenal content was around 0.8% and 2.4% of the parent carotenoid, in the C. sorokiniana and T. chuii strains, respectively. This methodology could be applied as a selective and efficient method for the apocarotenoids detection. Full article
(This article belongs to the Special Issue Carotenoids)
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11 pages, 1401 KiB  
Article
In Vitro Antioxidant, Antityrosinase, and Cytotoxic Activities of Astaxanthin from Shrimp Waste
by Sutasinee Chintong, Wipaporn Phatvej, Ubon Rerk-Am, Yaowapha Waiprib and Wanwimol Klaypradit
Antioxidants 2019, 8(5), 128; https://doi.org/10.3390/antiox8050128 - 13 May 2019
Cited by 65 | Viewed by 8587
Abstract
Astaxanthin is a potent antioxidant compared with vitamins and other antioxidants. However, astaxanthin extract from shrimp processing waste has not yet been used in cosmetic products. This study aimed to explore the natural astaxanthin from shrimp shells for antioxidant and antityrosinase activities as [...] Read more.
Astaxanthin is a potent antioxidant compared with vitamins and other antioxidants. However, astaxanthin extract from shrimp processing waste has not yet been used in cosmetic products. This study aimed to explore the natural astaxanthin from shrimp shells for antioxidant and antityrosinase activities as well as potential toxicity. The antioxidant activities were performed with 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging, β-carotene bleaching, and singlet oxygen quenching assays. The results revealed that astaxanthin extract demonstrated potent antioxidant activities against DPPH and ABTS radicals, and prevented the bleaching of β-carotene and quenching of singlet oxygen (EC50 17.5 ± 3.6, 7.7 ± 0.6, 15.1 ± 1.9 and 9.2 ± 0.5 μg/mL, respectively). Furthermore, the astaxanthin extract could inhibit tyrosinase activity (IC50 12.2 ± 1.5 μg/mL) and had no toxic effects on human dermal fibroblast cells. These results suggested that shrimp astaxanthin would be a promising dietary supplement for skin health applications. Full article
(This article belongs to the Special Issue Carotenoids)
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16 pages, 2532 KiB  
Article
Bioactive Compounds and Antioxidant Capacity of Rosa rugosa Depending on Degree of Ripeness
by Ahlam Al-Yafeai, Peter Bellstedt and Volker Böhm
Antioxidants 2018, 7(10), 134; https://doi.org/10.3390/antiox7100134 - 03 Oct 2018
Cited by 16 | Viewed by 4330
Abstract
Maturity stage affects the bioactive compounds as well as the antioxidant capacity in the fruit. This study was designed to identify and quantify carotenoids, as well as to evaluate vitamin E, vitamin C, antioxidant capacity and total phenolic compounds of Rosa rugosa hips [...] Read more.
Maturity stage affects the bioactive compounds as well as the antioxidant capacity in the fruit. This study was designed to identify and quantify carotenoids, as well as to evaluate vitamin E, vitamin C, antioxidant capacity and total phenolic compounds of Rosa rugosa hips at different degrees of ripeness. HPLC (high performance liquid chromatography) analysis showed different types of carotenoids at different stages of maturity of R. rugosa hips with significant differences (p ˂ 0.05), where the maximum concentration was observed at late harvesting. In the hips investigated, only α-tocopherol was detected, the maximum concentration of both vitamin E and vitamin C was obtained in the orange hips with significant difference (p ˂ 0.05). On the other hand, the highest hydrophilic and lipophilic TEAC (Trolox equivalent antioxidant capacity) values, as well as total phenolic contents, were determined in the mature hips (red colour) with significant difference (p < 0.0001) and (p < 0.001) respectively, whereas ORAC (oxygen radical absorbance capacity) showed lower activity in the mature hips with significant difference (p ˂ 0.05). Late harvesting is recommended if a high content of carotenoids is desired, while harvesting should be carried out earlier if a higher vitamin E and vitamin C content is desired, which in turn affects the antioxidants capacity. Full article
(This article belongs to the Special Issue Carotenoids)
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Review

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19 pages, 1921 KiB  
Review
Do We Utilize Our Knowledge of the Skin Protective Effects of Carotenoids Enough?
by Anamaria Balić and Mislav Mokos
Antioxidants 2019, 8(8), 259; https://doi.org/10.3390/antiox8080259 - 31 Jul 2019
Cited by 56 | Viewed by 10981
Abstract
Due to their potential health-promoting effects, carotenoids have drawn both scientific and public attention in recent years. The primary source of carotenoids in the human skin is diet, mainly fruits, vegetables, and marine product, but they may originate from supplementation and topical application, [...] Read more.
Due to their potential health-promoting effects, carotenoids have drawn both scientific and public attention in recent years. The primary source of carotenoids in the human skin is diet, mainly fruits, vegetables, and marine product, but they may originate from supplementation and topical application, too. In the skin, they accumulate mostly in the epidermis and act as a protective barrier to various environmental influences. Namely, the skin is exposed to numerous environmental factors, including ultraviolet radiation (UVR), air pollution, and smoking, that cause oxidative stress within the skin with consequent premature (extrinsic) aging. UVR, as the most prominent environmental factor, may cause additional detrimental skin effects, such as sunburn, DNA damage, and skin cancer. Therefore, photoprotection is the first line intervention in the prevention of premature aging and skin cancer. Numerous studies have demonstrated that carotenoids, particularly β-carotene, lycopene, lutein, and astaxanthin, have photoprotective effects, not only through direct light-absorbing properties, but also through their antioxidant effects (scavenging reactive oxygen species), as well as by regulation of UV light-induced gene expression, modulation of stress-dependent signaling, and/or suppression of cellular and tissue responses like inflammation. Interventional studies in humans with carotenoid-rich diet have shown its photoprotective effects on the skin (mostly by decreasing the sensitivity to UVR-induced erythema) and its beneficial effects in prevention and improvement of skin aging (improved skin elasticity and hydration, skin texture, wrinkles, and age spots). Furthermore, carotenoids may be helpful in the prevention and treatment of some photodermatoses, including erythropoietic protoporphyria (EPP), porphyria cutanea tarda (PCT) and polymorphous light eruption (PMLE). Although UVR is recognized as the main etiopathogenetic factor in the development of non-melanoma skin cancer (NMSC) and melanoma, and the photoprotective effects of carotenoids are certain, available studies still could not undoubtedly confirm the protective role of carotenoids in skin photocarcinogenesis. Full article
(This article belongs to the Special Issue Carotenoids)
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23 pages, 897 KiB  
Review
Nutritional Importance of Carotenoids and Their Effect on Liver Health: A Review
by Laura Inés Elvira-Torales, Javier García-Alonso and María Jesús Periago-Castón
Antioxidants 2019, 8(7), 229; https://doi.org/10.3390/antiox8070229 - 19 Jul 2019
Cited by 129 | Viewed by 10435
Abstract
The consumption of carotenoids has beneficial effects on health, reducing the risk of certain forms of cancer, cardiovascular diseases, and macular degeneration, among others. The mechanism of action of carotenoids has not been clearly identified; however, it has been associated with the antioxidant [...] Read more.
The consumption of carotenoids has beneficial effects on health, reducing the risk of certain forms of cancer, cardiovascular diseases, and macular degeneration, among others. The mechanism of action of carotenoids has not been clearly identified; however, it has been associated with the antioxidant capacity of carotenoids, which acts against reactive oxygen species and inactivating free radicals, although it has also been shown that carotenoids modulate gene expression. Dietary carotenoids are absorbed and accumulated in the liver and other organs, where they exert their beneficial effects. In recent years, it has been described that the intake of carotenoids can significantly reduce the risk of suffering from liver diseases, such as non-alcoholic fatty liver disease (NAFLD). This disease is characterized by an imbalance in lipid metabolism producing the accumulation of fat in the hepatocyte, leading to lipoperoxidation, followed by oxidative stress and inflammation. In the first phases, the main treatment of NAFLD is to change the lifestyle, including dietary habits. In this sense, carotenoids have been shown to have a hepatoprotective effect due to their ability to reduce oxidative stress and regulate the lipid metabolism of hepatocytes by modulating certain genes. The objective of this review was to provide a description of the effects of dietary carotenoids from fruits and vegetables on liver health. Full article
(This article belongs to the Special Issue Carotenoids)
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13 pages, 2818 KiB  
Review
Antioxidant Protection from UV- and Light-Stress Related to Carotenoid Structures
by Gerhard Sandmann
Antioxidants 2019, 8(7), 219; https://doi.org/10.3390/antiox8070219 - 11 Jul 2019
Cited by 74 | Viewed by 7234
Abstract
This review summarizes studies of protection against singlet oxygen and radical damage by carotenoids. The main focus is on how substitutions of the carotenoid molecules determine high antioxidant activities such as singlet oxygen quenching and radical scavenging. Applied assays were carried out either [...] Read more.
This review summarizes studies of protection against singlet oxygen and radical damage by carotenoids. The main focus is on how substitutions of the carotenoid molecules determine high antioxidant activities such as singlet oxygen quenching and radical scavenging. Applied assays were carried out either in vitro in solvents or with liposomes, and in a few cases with living organisms. In the latter, protection by carotenoids especially of photosynthesis against light- and UV-stress is of major importance, but also heterotrophic organisms suffer from high light and UV exposure which can be alleviated by carotenoids. Carotenoids to be compared include C30, C40 and C50 molecules either acyclic, monocyclic or bicyclic with different substitutions including sugar and fatty acid moieties. Although some studies are difficult to compare, there is a tendency towards mono and bicyclic carotenoids with keto groups at C-4/C-4’ and the longest possible polyene structure functions to act best in singlet oxygen quenching and radical scavenging. Size of the carotenoid and lipophilic substituents such as fatty acids seem to be of minor importance for their activity but hydroxyl groups at an acyclic end and especially glycosylation of these hydroxyl groups enhance carotenoid activity. Full article
(This article belongs to the Special Issue Carotenoids)
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