A carotenoid algal preparation containing phytoene and phytofluene inhibited LDL oxidation in vitro

Biological Potential, Gastrointestinal Digestion, Absorption, and Bioavailability of Algae-Derived Compounds with Neuroprotective Activity: A Comprehensive Review

Currently, there is no known cure for neurodegenerative disease. However, the available therapies aim to manage some of the symptoms of the disease. Human neurodegenerative diseases are a heterogeneous group of illnesses characterized by progressive loss of neuronal cells and nervous system dysfunction related to several mechanisms such as protein aggregation, neuroinflammation, oxidative stress, and neurotransmission dysfunction. Neuroprotective compounds are essential in the prevention and management of neurodegenerative diseases. This review will focus on the neurodegeneration mechanisms and the compounds (proteins, polyunsaturated fatty acids (PUFAs), polysaccharides, carotenoids, phycobiliproteins, phenolic compounds, among others) present in seaweeds that have shown in vivo and in vitro neuroprotective activity. Additionally, it will cover the recent findings on the neuroprotective effects of bioactive compounds from macroalgae, with a focus on their biological potential and possible mechanism of action, including microbiota modulation. Furthermore, gastrointestinal digestion, absorption, and bioavailability will be discussed. Moreover, the clinical trials using seaweed-based drugs or extracts to treat neurodegenerative disorders will be presented, showing the real potential and limitations that a specific metabolite or extract may have as a new therapeutic agent considering the recent approval of a seaweed-based drug to treat Alzheimer’s disease.

Carotenoids from Marine Sources as a New Approach in Neuroplasticity Enhancement

An increasing number of people experience disorders related to the central nervous system (CNS). Thus, new forms of therapy, which may be helpful in repairing processes' enhancement and restoring declined brain functions, are constantly being sought. One of the most relevant physiological processes occurring in the brain for its entire life is neuroplasticity. It has tremendous significance concerning CNS disorders since neurological recovery mainly depends on restoring its structural and functional organization. The main factors contributing to nerve tissue damage are oxidative stress and inflammation. Hence, marine carotenoids, abundantly occurring in the aquatic environment, being potent antioxidant compounds, may play a pivotal role in nerve cell protection. Furthermore, recent results revealed another valuable characteristic of these compounds in CNS therapy. By inhibiting oxidative stress and neuroinflammation, carotenoids promote synaptogenesis and neurogenesis, consequently presenting neuroprotective activity. Therefore, this paper focuses on the carotenoids obtained from marine sources and their impact on neuroplasticity enhancement.

Assessment of Food Sources and the Intake of the Colourless Carotenoids Phytoene and Phytofluene in Spain

Phytoene (PT) and phytofluene (PTF), colorless carotenoids, have largely been ignored in food science studies, food technology, and nutrition. However, they are present in commonly consumed foods and may have health-promotion effects and possible uses as cosmetics. The goal of this study is to assess the most important food sources of PT and PTF and their dietary intakes in a representative sample of the adult Spanish population. A total of 62 food samples were analyzed (58 fruit and vegetables; seven items with different varieties/color) and carotenoid data of four foods (three fruits and one processed food) were compiled. PT concentration was higher than that of PTF in all the foods analyzed. The highest PT content was found in carrot, apricot, commercial tomato juice, and orange (7.3, 2.8, 2.0, and 1.1 mg/100 g, respectively). The highest PTF level was detected in carrots, commercial tomato sauce and canned tomato, apricot, and orange juice (1.7, 1.2, 1.0, 0.6, and 0.04 mg/100 g, respectively). The daily intakes of PT and PTF were 1.89 and 0.47 mg/person/day, respectively. The major contributors to the dietary intake of PT (98%) and PTF (73%) were: carrot, tomato, orange/orange juice, apricot, and watermelon. PT and PTF are mainly supplied by vegetables (81% and 69%, respectively). Considering the color of the edible part of the foods analyzed (fruit, vegetables, sauces, and beverages), the major contributor to the daily intake of PT and PTF (about 98%) were of red/orange color.

Mitosis Inhibitors Induce Massive Accumulation of Phytoene in the Microalga Dunaliella salina

Phytoene is a colourless natural carotenoid that absorbs UV light and provides antioxidant and anti-inflammatory activities as well as protection against photodamage. It is therefore valued for its skin health and aesthetic benefits by the cosmetic industry, as well as by the health food sector. The halotolerant green microalga Dunaliella salina is one of the richest sources of natural carotenoids. We have previously investigated the over-production of phytoene in D. salina after cultivation with the well-characterised mitosis inhibitor, chlorpropham. In this study, 15 herbicides with different modes of action were tested for their potential to promote phytoene accumulation. All herbicides showed different levels of capabilities to support phytoene over-production in D. salina. Most significantly, the two mitosis inhibitors tested in this study, propyzamide and chlorpropham, showed similar capacities to support the over-production of phytoene by D. salina cultures as phytoene desaturase inhibitors. The cellular content of phytoene increased by over 10-fold within 48 h of treatment with the mitosis inhibitors compared to untreated cultures. Results indicate a general effect of mitosis inhibitors on phytoene accumulation in D. salina. Furthermore, red light was found to significantly enhance the phytoene yield when used in combination with effective inhibitor treatments. Red light can be applied to maximize the production of phytoene from D. salina.

Carotenoids: Therapeutic Strategy in the Battle against Viral Emerging Diseases, COVID-19: An Overview

Carotenoids, a group of phytochemicals, are naturally found in the Plant kingdom, particularly in fruits, vegetables, and algae. There are more than 600 types of carotenoids, some of which are thought to prevent disease, mainly through their antioxidant properties. Carotenoids exhibit several biological and pharmaceutical benefits, such as anti-inflammatory, anti-cancer, and immunity booster properties, particularly as some carotenoids can be converted into vitamin A in the body. However, humans cannot synthesize carotenoids and need to obtain them from their diets or via supplementation. The emerging zoonotic virus severe acute respiratory syndrome coronavirus 2, which causes coronavirus disease 2019 (COVID-19), originated in bats, and was transmitted to humans. COVID-19 continues to cause devastating international health problems worldwide. Therefore, natural preventive therapeutic strategies from bioactive compounds, such as carotenoids, should be appraised for strengthening physiological functions against emerging viruses. This review summarizes the most important carotenoids for human health and enhancing immunity, and their potential role in COVID-19 and its related symptoms. In conclusion, promising roles of carotenoids as treatments against emerging disease and related symptoms are highlighted, most of which have been heavily premeditated in studies conducted on several viral infections, including COVID-19. Further in vitro and in vivo research is required before carotenoids can be considered as potent drugs against such emerging diseases.

Carotenoids as Novel Therapeutic Molecules Against Neurodegenerative Disorders: Chemistry and Molecular Docking Analysis

Alzheimer's disease (AD) is the most devastating neurodegenerative disorder that affects the aging population worldwide. Endogenous and exogenous factors are involved in triggering this complex and multifactorial disease, whose hallmark is Amyloid-β (Aβ), formed by cleavage of amyloid precursor protein by β- and γ-secretase. While there is no definitive cure for AD to date, many neuroprotective natural products, such as polyphenol and carotenoid compounds, have shown promising preventive activity, as well as helping in slowing down disease progression. In this article, we focus on the chemistry as well as structure of carotenoid compounds and their neuroprotective activity against Aβ aggregation using molecular docking analysis. In addition to examining the most prevalent anti-amyloidogenic carotenoid lutein, we studied cryptocapsin, astaxanthin, fucoxanthin, and the apocarotenoid bixin. Our computational structure-based drug design analysis and molecular docking simulation revealed important interactions between carotenoids and Aβ via hydrogen bonding and van der Waals interactions, and shows that carotenoids are powerful anti-amyloidogenic molecules with a potential role in preventing AD, especially since most of them can cross the blood-brain barrier and are considered nutraceutical compounds. Our studies thus illuminate mechanistic insights on how carotenoids inhibit Aβ aggregation. The potential role of carotenoids as novel therapeutic molecules in treating AD and other neurodegenerative disorders are discussed.

Skin Carotenoids in Public Health and Nutricosmetics: The Emerging Roles and Applications of the UV Radiation-Absorbing Colourless Carotenoids Phytoene and Phytofluene

In this work, the importance of dietary carotenoids in skin health and appearance is comprehensively reviewed and discussed. References are made to their applications in health-promoting and nutricosmetic products and the important public health implications that can be derived. Attention is focused on the colourless UV radiation (UVR)-absorbing dietary carotenoids phytoene and phytofluene, which are attracting increased interest in food science and technology, nutrition, health and cosmetics. These compounds are major dietary carotenoids, readily bioavailable, and have been shown to be involved in several health-promoting actions, as pinpointed in recent reviews. The growing evidence that these unique UVR-absorbing carotenoids with distinctive structures, properties (light absorption, susceptibility to oxidation, rigidity, tendency to aggregation, or even fluorescence, in the case of phytofluene) and activities can be beneficial in these contexts is highlighted. Additionally, the recommendation that the levels of these carotenoids are considered in properly assessing skin carotenoid status is made.

Preliminary Data on the Safety of Phytoene- and Phytofluene-Rich Products for Human Use including Topical Application

The colorless carotenoids phytoene and phytofluene are comparatively understudied compounds found in common foods (e.g., tomatoes) and in human plasma, internal tissues, and skin. Being naturally present in common foods, their intake at dietary levels is not expected to present a safety concern. However, since the interest in these compounds in the context of many applications is expanding, it is important to conduct studies aimed at assessing their safety. We present here results of in vitro cytotoxicity and genotoxicity studies, revealing no significant cytotoxic or genotoxic potential and of short- and long-term human in vivo skin compatibility studies with phytoene- and phytofluene-rich tomato and Dunaliella salina alga extracts, showing a lack of irritancy or sensitization reactions. These results support the safe use of phytoene- and phytofluene-rich products in human topical applications.

Absorption and Distribution Kinetics of the 13C-Labeled Tomato Carotenoid Phytoene in Healthy Adults

BACKGROUND

Phytoene is a tomato carotenoid that may contribute to the apparent health benefits of tomato consumption. Although phytoene is a less prominent tomato carotenoid than lycopene, it is a major carotenoid in various human tissues. Phytoene distribution to plasma lipoproteins and tissues differs from lycopene, suggesting the kinetics of phytoene and lycopene differ.

OBJECTIVE

The objective of this study was to characterize the kinetic parameters of phytoene absorption, distribution, and excretion in adults, to better understand why biodistribution of phytoene differs from lycopene.

METHODS

Four adults (2 males, 2 females) maintained a controlled phytoene diet (1-5 mg/d) for 42 d. On day 14, each consumed 3.2 mg (13)C-phytoene, produced using tomato cell suspension culture technology. Blood samples were collected at 0, 1-15, 17, 21, and 24 h and 2, 3, 4, 7, 10, 14, 17, 21, and 28 d after (13)C-phytoene consumption. Plasma-unlabeled and plasma-labeled phytoene concentrations were determined using ultra-HPLC-quadrupole time-of-flight-mass spectrometry, and data were fit to a 7-compartment carotenoid kinetic model using WinSAAM 3.0.7 software.

RESULTS

Subjects were compliant with a controlled phytoene diet, consuming a mean ± SE of 2.5 ± 0.6 mg/d, resulting in a plasma unlabeled phytoene concentration of 71 ± 14 nmol/L. A maximal plasma (13)C-phytoene concentration of 55.6 ± 5.9 nM was achieved 19.8 ± 9.2 h after consumption, and the plasma half-life was 2.3 ± 0.2 d. Compared with previous results for lycopene, phytoene bioavailability was nearly double at 58% ± 19%, the clearance rate from chylomicrons was slower, and the rates of deposition into and utilization by the slow turnover tissue compartment were nearly 3 times greater.

CONCLUSIONS

Although only differing from lycopene by 4 double bonds, phytoene exhibits markedly different kinetic characteristics in human plasma, providing insight into metabolic processes contributing to phytoene enrichment in plasma and tissues compared with lycopene. This trial was registered at clinicaltrials.gov as NCT01692340.

Free radical scavenging properties of phytofluene and phytoene isomers as compared to lycopene: a combined experimental and theoretical study

Free radical scavenging properties of Lycopene (LYC), Phytofluene (PF), and Phytoene (PE) are studied experimentally, considering the electron transfer mechanism and using the ABTS(•+) decolouration assay. Density Functional Theory is used to obtain the theoretical UV-visible spectra of ABTS (neutral and cation) and to determine the free radical scavenger capacity in terms of the electron donor mechanism and the deactivation of singlet oxygen. The experimental data agreed very well with the theoretical results. Considering both mechanisms, LYC, PF, and PE can be considered good free radical scavengers, with LYC turning out to be the best and PE the worst antiradical. However, the triplets that formed following the deactivation of singlet oxygen presented similar capacity for donating electrons. In the case of triplets, the antiradical capacity of LYC, PF, and PE is similar in terms of the electron donor mechanism. Although the results indicated that PF and PE are not as effective antiradicals as LYC, which is to be expected due to the number of conjugated double bonds, they do present a higher antioxidant capacity than expected considering the small number of conjugated double bonds.

The effect of solvent extraction on antioxidant properties of apricot fruit

Two solvent extraction procedures were used to investigate the extraction efficiency in terms of total antioxidant capacity and total phenols in apricot fruit. Samples were either sequentially extracted with aqueous ethanol (ethanol/water 80% v/v) and tetrahydrofuran or directly extracted with tetrahydrofuran. Each extract was analyzed for total antioxidant capacity by the Trolox Equivalent Antioxidant Capacity (TEAC) assay and total phenols by the Folin-Ciocalteu assay. The results showed that using sequential solvent extraction, the majority (85%) of the total antioxidant capacity and total phenols was due to hydrophilic compounds. In tetrahydrofuran direct extractions, the total antioxidant capacity and total phenols were higher than values obtained with aqueous ethanol and the sum of results obtained from sequential extracts for either total antioxidant capacity or total phenols was similar to the tetrahydrofuran-extract antioxidant values. A linear correlation between total antioxidant capacity and total phenols was found and was independent of the solvent extraction method. In conclusion, the choice of solvent is related to the antioxidant potential of fruit and depends on the food hydrophilic/lipophilic composition.

Nutritional aspects of phytoene and phytofluene, carotenoid precursors to lycopene

Epidemiological studies suggest an inverse relationship between tomato consumption and serum and tissue lycopene (LYC) levels with risk of some chronic diseases, including several cancers and cardiovascular disease. LYC, the red carotenoid found in tomatoes, is often considered to be the primary bioactive carotenoid in tomatoes that mediates health benefits, but other colorless precursor carotenoids, phytoene (PE) and phytofluene (PF), are also present in substantial quantities. PE and PF are readily absorbed from tomato foods and tomato extracts by humans. Animal models of carotenoid absorption suggest preferential accumulation of PE and PF in some tissues. The reasonably high concentrations of PE and PF detected in serum and tissues relative to the concentrations in foods suggest that absorption or metabolism of these compounds may be different from that of LYC. Experimental studies, both in vitro and in vivo, suggest that PE and PF exhibit bioactivity but little is known about their impact in humans. Methods for producing isotopically labeled PE, PF, and LYC tracers from tomato plant cell culture offer a unique tool for further understanding the differential bioavailability and metabolism of these 3 prominent tomato carotenoids and how they may affect health.

Pomological and nutraceutical properties in apricot fruit: cultivation systems and cold storage fruit management

We have investigated the effect of cultivation systems and fruit post-harvest management on the antioxidant properties of apricot fruits. Trees of five cultivars 'Tyrinthos', 'Cafona', 'Bella d'Italia', 'Vitillo' and 'Pellecchiella' were cultivated under integrated and organic systems. Fruits were collected at full maturity stage and analyzed either immediately or after storage at 4+/-0.5 degrees C and 85% of relative humidity for seven and 14 days. The main pomological traits (weight, colour, flesh firmness, total soluble sugars, titratable acidity) and antioxidant properties were analyzed. The total antioxidant capacity (TAC by TEAC method), total phenols content (TP by Folin-Ciocalteu method) and carotenoid content by HPLC-DAD were monitored. Cultivar characterization by principal component analysis (PCA) indicated a large variability on pomological and antioxidant properties of apricot fruits. 'Bella d'Italia' showed better TAC and TP values compared to the other cultivars. ANOVA interactions between cultivar and cultivation system (organic/integrated) were found for the antioxidant properties. These interactions may help to select a set of genotypes with better performances under organic system, which in our study might be indicated in 'Cafona' and 'Bella d'Italia'.