Decreased formulation pH and protein preheating treatment enhance the interaction, storage stability, and bioaccessibility of caseinate-bound lutein/zeaxanthin.

Heat treatment and pH are crucial factors in the formulation and processing of food and beverages; thus, a thorough understanding of the impact of these factors on the interactions between bioactive constituents and proteins is essential to developing effective protein-based delivery systems. This study explores the influences of pH (ranged from 1.5 to 7.5) and preheating treatment on the characteristics of caseinates-lutein (LU)/zeaxanthin (ZX) complexes and evaluates the potential application of caseinates as protective carriers in xanthophyll-fortified beverages. The properties and interactions of caseinates and two xanthophylls were systematically investigated utilizing a range of spectroscopic techniques, including ultraviolet-visible (UV-Vis) spectroscopy, dynamic light scattering (DLS), fluorescence spectroscopy, and Fourier transform infrared (FTIR) spectroscopy. Caseinates were bound to LU/ZX with a binding constant of the order 105 M-1. Furthermore, ZX exhibited a higher affinity for caseinates than LU. In particular, the decreased pH level of complex formulation and the preheating of caseinates at 85 °C strengthened the binding affinity between LU/ZX and caseinates. The caseinate-LU/ZX complexes effectively improved the chemical stability of LU/ZX and achieved a bioaccessibility rate of over 70 %. This study provides a guide for developing commercially available xanthophyll-fortified beverages and further expanding the application of caseinates as encapsulation carriers for extremely hydrophobic nutrients in the food industry.

Bioaccessibility of carotenoids, tocochromanols, and iron from common bean (Phaseolus vulgaris L.) landraces.

Common beans (Phaseolus vulgaris L.) are among the most important legumes for human nutrition. The aim of the present study was to characterize the composition and in vitro bioaccessibility of tocochromanols, carotenoids, and iron from 14 different landraces and 2 commercial common bean varieties. Phytic acid, dietary fiber, and total (poly)phenolic content were determined as factors that can modify the bioaccessibility of the studied compounds. Two carotenoids were identified, namely lutein (4.6-315 ng/g) and zeaxanthin (12.2-363 ng/g), while two tocochromanols were identified, namely γ-tocopherol (2.62-18.01 µg/g), and δ-tocopherol (0.143-1.44 µg/g). The iron content in the studied samples was in the range of 58.7-144.2 µg/g. The contents of carotenoids, tocochromanols, and iron differed significantly among the studied samples but were within the ranges reported for commercial beans. After simulated gastrointestinal digestion, the average bioaccessibility of carotenoids was 30 %, for tocochromanols 50 %, and 17 % for iron. High variability in the bioaccessible content yielded by the bean varieties was observed. Dietary fiber, phytic acid and total (poly)phenol contents were negatively correlated with the bioaccessibility of carotenoids, while iron bioaccessibility was negatively correlated with the total (poly)phenol content. The principal component analysis indicated that the bioaccessibility of lutein was the main variable involved in class separations. The composition of the food matrix plays an important role in the bioaccessibility of carotenoids, tocochromanols and iron from cooked beans.

Multiple Mechanisms of Haematococcus pluvialis-Derived Carotenoids to Inhibit Glycidyl Ester Formation in Rice Oil and a Chemical Model at High Temperatures.

The common presence of glycidyl esters (GEs) in refined vegetable oils has been a concern for food safety. The present study aimed to investigate the inhibitory effects of three carotenoids derived from Haematococcus pluvialis microalga on GE formation in both rice oil and a chemical model during heating. The addition of astaxanthin (AS), lutein (LU), and ß-carotene (CA) at 0.6 mg/g in rice oil can reduce GE formation by 65.0%, 57.1%, and 57.5%, respectively, which are significantly higher than those achieved by common antioxidants such as l-ascorbyl palmitate (39.0%), α-tocopherol (18.5%), tert-butyl hydroquinone (42.7%), and quercetin (26.2%). UPLC-Q-TOF-MS/MS analysis showed that two new compounds, that is, propylene glycol monoester and diester of palmitic acid, were formed in the CA-added chemical model, which provided direct experimental evidence for the inhibition of antioxidants including AS, LU, and CA against GE formation not only by indirect antioxidative action but also by direct radical reactions to competitively prevent the formation of cyclic acyloxonium intermediates. Furthermore, it was interestingly found that only AS could react with the GEs. The adduct of AS with GEs, astaxanthin-3-O-propanetriol esters, was preliminarily identified using Q-TOF-MS/MS in the heated AS-GE model, suggesting that reacting with GEs might represent another distinct mechanism of AS to eliminate GEs.

The impact of lutein-loaded poly(lactic-co-glycolic acid) nanoparticles following topical application: An in vitro and in vivo study.

Antioxidant therapies are of interest in the prevention and management of ocular disorders such as cataracts. Although an active area of interest, topical therapy with antioxidants for the treatment of cataracts is complicated by multiple ocular anatomical barriers, product stability, and solubility. Entrapment and delivery of antioxidants with poly(lactic-co-glycolic acid) nanoparticles is a possible solution to these challenges, however, little is known regarding their effects in vitro or in vivo. Our first aim was to investigate the impact of blank and lutein loaded PLGA nanoparticles on viability and development of reactive oxygen species in lens epithelial cells in vitro. Photo-oxidative stress was induced by ultraviolet light exposure with cell viability and reactive oxygen species monitored. Next, an in vivo, selenite model was utilized to induce cataract formation in rodents. Eyes were treated topically with both free lutein and lutein loaded nanoparticles (LNP) at varying concentrations. Eyes were monitored for the development of anterior segment changes and cataract formation. The ability of nanodelivered lutein to reach the anterior segment of the eye was evaluated by liquid chromatography coupled to mass spectrometry of aqueous humor samples and liquid chromatography coupled to tandem mass spectrometry (targeted LC-MS/MS) of lenses. LNP had a minimal impact on the viability of lens epithelial cells during the short exposure timeframe (24 h) and at concentrations < 0.2 µg LNP/µl. A significant reduction in the development of reactive oxygen species was also noted. Animals treated with LNPs at an equivalent lutein concentration of 1,278 µg /mL showed the greatest reduction in cataract scores. Lutein delivery to the anterior segment was confirmed through evaluation of aqueous humor and lens sample evaluation. Topical treatment was not associated with the development of secondary keratitis or anterior uveitis when applied once daily for one week. LNPs may be an effective in the treatment of cataracts.

Genetic Engineering and Innovative Cultivation Strategies for Enhancing the Lutein Production in Microalgae.

Carotenoids, with their diverse biological activities and potential pharmaceutical applications, have garnered significant attention as essential nutraceuticals. Microalgae, as natural producers of these bioactive compounds, offer a promising avenue for sustainable and cost-effective carotenoid production. Despite the ability to cultivate microalgae for its high-value carotenoids with health benefits, only astaxanthin and ß-carotene are produced on a commercial scale by Haematococcus pluvialis and Dunaliella salina, respectively. This review explores recent advancements in genetic engineering and cultivation strategies to enhance the production of lutein by microalgae. Techniques such as random mutagenesis, genetic engineering, including CRISPR technology and multi-omics approaches, are discussed in detail for their impact on improving lutein production. Innovative cultivation strategies are compared, highlighting their advantages and challenges. The paper concludes by identifying future research directions, challenges, and proposing strategies for the continued advancement of cost-effective and genetically engineered microalgal carotenoids for pharmaceutical applications.

Neurodevelopmental changes in Drosophila melanogaster are restored by treatment with lutein-loaded nanoparticles: Positive modulation of neurochemical and behavioral parameters.

Neurodevelopmental disorders, such as autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD), are characterized by persistent changes in communication and social interaction, as well as restricted and stereotyped patterns of behavior. The complex etiology of these disorders possibly combines the effects of multiple genes and environmental factors. Hence, exposure to insecticides such as imidacloprid (IMI) has been used to replicate the changes observed in these disorders. Lutein is known for its anti-inflammatory and antioxidant properties and is associated with neuroprotective effects. Therefore, the aim of this study was to evaluate the protective effect of lutein-loaded nanoparticles, along with their mechanisms of action, on Drosophila melanogaster offspring exposed to IMI-induced damage. To simulate the neurodevelopmental disorder model, flies were exposed to a diet containing IMI for 7 days. Posteriorly, their offspring were exposed to a diet containing lutein-loaded nanoparticles for a period of 24 h, and male and female flies were subjected to behavioral and biochemical evaluations. Treatment with lutein-loaded nanoparticles reversed the parameters of hyperactivity, aggressiveness, social interaction, repetitive movements, and anxiety in the offspring of flies exposed to IMI. It also protected markers of oxidative stress and cell viability, in addition to preventing the reduction of Nrf2 and Shank3 immunoreactivity. These results demonstrate that the damage induced by exposure to IMI was restored through treatment with lutein-loaded nanoparticles, elucidating lutein's mechanisms of action as a therapeutic agent, which, after further studies, can become a co-adjuvant in the treatment of neurodevelopmental disorders, such as ASD and ADHD.

Light emitting diodes as alternative light source for growth and carotenoid enhancement in Chlorococcum humicola Cultured in airlift photobioreactors.

This study compares the performance of white light emitting diodes (LEDs) and fluorescent lamps for cultivating Chlorococcum humicola (C. humicola) as aquaculture feed. Results demonstrate that daylight LEDs are seen to yield the highest biomass concentration at 1,010 ± 11 mg/L, exceeding fluorescent lamps by 36 %. Switching to daylight LEDs increased carotenoid content in algal biomass from 2.97 ± 0.23 to 3.86 ± 0.15 mg/g and carotenoid concentration from 2.21 ± 0.16 to 3.90 ± 0.27 mg/L: increases of 36 % and 76 %, respectively. Blue and daylight LEDs proved to be most effective for lutein induction, with less impact on beta-carotene. Biomass under daylight LEDs shows promising values for protein and lipid contents of 32 % and 11 % dry weight, respectively. Daylight LEDs consumed less than half the energy of fluorescent lamps. Daylight LEDs significantly enhance the growth and carotenoid content of C. humicola, offering a sustainable alternative for aquaculture feed production.

Serum carotenoid levels inversely correlate with depressive symptoms among adults: Insights from NHANES data.

BACKGROUND: Carotenoids are a group of tetraterpenoid lipophilic pigments linked to depression, but studies on individual carotenoid components are lacking. We aimed to assess the association between each serum carotenoids and depressive symptoms in adults. METHODS: This cross-sectional study included 7264 adults from the National Health and Nutrition Examination Survey (NHANES). Serum carotenoid levels (α-carotene, ß-carotene, ß-cryptoxanthin, lycopene, and lutein/zeaxanthin) were measured using high-performance liquid chromatography. Participants with a Patient Health Questionnaire score ≥ 10 were considered to have depressive symptoms. The association between each carotenoid and depressive symptoms was investigated using multivariable-adjusted logistic regression, restricted cubic spline, and weighted quantile sum regression models. RESULTS: The participants' average age was 46.0 (interquartile range: 34.0-60.0) years (50.9 % females), and 545 participants (7.5 %) were diagnosed with depressive symptoms. The logistic regression model demonstrated that high serum α-carotene, ß-carotene, ß-cryptoxanthin, and lutein/zeaxanthin levels were associated with a lower likelihood of depressive symptoms. The restricted cubic spline model revealed that the significantly inverse relationships between serum carotenoid levels and the risk of depressive symptoms were nonlinear for α-carotene, ß-carotene, ß-cryptoxanthin, and lutein/zeaxanthin and were linear for lycopene. The threshold effect analysis further identified the inflection points were 12.1, 35.7, 5.9, and 7.7 µg/dL for α-carotene, ß-carotene, ß-cryptoxanthin, and lutein/zeaxanthin, respectively. The weighted quantile sum regression model revealed that ß-cryptoxanthin (35.2 %) and α-carotene (34.5 %) were the top-weighted carotenoids correlated with depressive symptoms. CONCLUSIONS: The present results suggested an association between higher levels of each serum carotenoids and a decreased risk of depressive symptoms in adults.

Walnut protein isolate based emulsion as a promising delivery system enhanced lutein bioaccessibility.

Lutein, a natural pigment with multiple beneficial bioactivities, faces limitations in food processing due to its instability. In this study, we constructed four modified walnut protein isolate (WNPI) based emulsions as emulsion-based delivery systems (EBDS) for lutein fortification. The modification treatments enhanced the encapsulation efficiency of the WNPI-based EBDS on lutein. The modified WNPI-based EBDS exhibited improved storage and digestive stability, as well as increased lutein delivery capability in simulated gastrointestinal conditions. After in vitro digestion, the lutein retention in the modified WNPI-based EBDS was higher than in the untreated WNPI-based EBDS, with a maximum retention of 49.67 ± 1.10 % achieved after ultrasonic modification. Furthermore, the modified WNPI-based EBDS exhibited an elevated lutein bioaccessibility, reaching a maximum value of 40.49 ± 1.29 % after ultrasonic modification, nearly twice as high as the untreated WNPI-based EBDS. Molecular docking analysis indicated a robust affinity between WNPI and lutein, involving hydrogen bonds and hydrophobic interactions. Collectively, this study broadens WNPI's application and provides a foundation for fortifying other fat-soluble bioactive substances.

In Vivo Correlation Between Macular Pigment Optical Volume and Retinal Layers Thickness.

Purpose: This study aims to investigate the potential in vivo relationship between macular pigment (MP) and retinal layers thickness in healthy subjects and dry, non-advanced age-related macular degeneration (AMD). Methods: An observational, cross-sectional study was conducted. Healthy subjects >40 years and patients with early or intermediate AMD were recruited. Structural OCT and macular pigment optical volume (MPOV) were collected for each subject. Retinal layers parameters were calculated based on the standard early treatment diabetic retinopathy study (ETDRS) map. Additionally, MPOV within 1°, 2°, and 9° of eccentricity was assessed and associated with retinal layers thickness and volume. Linear mixed-effects models were used to test the relationship between MP and structural OCT parameters, while adjusting for known possible confounding factors. Results: A total of 144 eyes of 91 subjects (60.4% females) were evaluated, comprising 43% normal eyes and 57% with early/intermediate AMD. Among the retinal layers, only the outer nuclear layer (ONL) thickness and volume appeared to be associated to higher MP levels. Specifically, the central ONL thickness was identified as a significant predictor of the MPOV 1°(P = 0.04), while the parafoveal ONL thickness (inner ETDRS subfield) was identified as a significant fixed effect on the MPOV 9° (P = 0.037). Age and the presence of drusen or subretinal drusenoid deposits were also tested without showing significant correlations. Conclusions: Among the retinal layers examined, only the ONL thickness demonstrated a significant association with MPOV. Consequently, ONL thickness might serve as a potential biomarker related to MP levels.

Light Intensity Enhances the Lutein Production in Chromochloris zofingiensis Mutant LUT-4.

Chromochloris zofingiensis, a unicellular green alga, is a potential source of natural carotenoids. In this study, the mutant LUT-4 was acquired from the chemical mutagenesis pool of C. zofingiensis strain. The biomass yield and lutein content of LUT-4 reached 9.23 g·L-1, and 0.209% of dry weight (DW) on Day 3, which was 49.4%, and 33% higher than that of wild-type (WT), respectively. The biomass yields of LUT-4 under 100, 300, and 500 µmol/m2/s reached 8.4 g·L-1, 7.75 g·L-1, and 6.6 g·L-1, which was 10.4%, 21%, and 29.6% lower compared with the control, respectively. Under mixotrophic conditions, the lutein yields were significantly higher than that obtained in the control. The light intensity of 300 µmol/m2/s was optimal for lutein biosynthesis and the content of lutein reached 0.294% of DW on Day 3, which was 40.7% more than that of the control. When LUT-4 was grown under 300 µmol/m2/s, a significant increase in expression of genes implicated in lutein biosynthesis, including phytoene synthase (PSY), phytoene desaturase (PDS), and lycopene epsilon cyclase (LCYe) was observed. The changes in biochemical composition, Ace-CoA, pyruvate, isopentenyl pyrophosphate (IPP), and geranylgeranyl diphosphate (GGPP) contents during lutein biosynthesis were caused by utilization of organic carbon. It was thereby concluded that 300 µmol/m2/s was the optimal culture light intensity for the mutant LUT-4 to synthesize lutein. The results would be helpful for the large-scale production of lutein.

Ca2+-nano starch-lutein endowed 3D printed surimi with antioxidation and mutual reinforcing transmembrane transport mechanisms via hepg2 and caco-2 cells model.

To better enhance printing effects meanwhile casting functionality, antioxidation and absorption of bioactive component in printed Ca2+-nano starch (NS)-lutein (L)-surimi were investigated. Results shown that Ca2+-NS-L promoted surimi printability due to enhanced gel strength and denser structure. Mixing Ca2+-NS-L endowed printed surimi with antioxidation (DPPH, ABTS, hydroxyl radical, Fe2+ reduction were 42 %, 79 %, 65 %, 0.104 mg·mL-1, respectively) due to the ability of lutein with more -OH groups and conjugate bonds to capture free radicals. It also manifested in cellular antioxidation that Ca2+-NS-L-surimi regulated the level of Nrf2 to protect gene expression of antioxidases (SOD, CAT, GSH-Px increased by 30-180 %, compared to damaged cells) through keap1-Nrf2-ARE pathway. Additionally, lutein absorption and transportation of Ca2+-NS-L-surimi increased by 20 %, compared to NS-L. Possibly, combination of samples and membrane was facilitated by surface hydrophobic, promoting endocytosis. Meanwhile, digestive surimi (peptides) with acidic-alkaline amino acids and negative charges made samples be attracted and moved in bypass parts under electrostatic traction and repulsion (electrostatic domain) to promote transport process. Also, Ca2+ facilitated CaM expression in membrane and formed Ca2+ channel by combining with CaM to accelerate entry of samples into cells. Conclusively, Ca2+-NS-L both strengthened printability of surimi and antioxidation, promoting application of printed functional surimi.

Diplotaxis erucoides and Oxalis pes-caprae: Two Wild Edible Plants as a New and Valuable Source of Carotenoids, Tocols and B1 and B2 Vitamins.

The aim of this study was to determine the profile and contents of carotenoids, tocols and B1 and B2 vitamins in different parts of two wild edible plants (WEPs), Diplotaxis erucoides and Oxalis pes-caprae. Results showed interesting amounts of these bioactive compounds in the leaves, with intakes higher than the Recommended Daily Allowance (RDA) for vitamin A and vitamin E after consumption of 100 g. Diplotaxis erucoides and Oxalis pes-caprae leaves evidenced high amounts of carotenoids, such as lutein (about 8 mg/100 g and 5 mg, respectively) and ß-carotene (about 8 mg/100 g and 4 mg/100 g, respectively). Even when not present at high amounts, the investigated plants can also contribute to the daily intake of thiamine and riboflavin. The rich profile and high contents of bioactive compounds in these WEPs clearly justify their potential use as food ingredients in a healthy and sustainable modern cuisine and in the development of new functional foods.

Associations of serum carotenoids with all-cause and cardiovascular mortality in adults with MAFLD.

BACKGROUND AND AIMS: The associations between serum carotenoids and mortality are contradictory in various metabolic-associated diseases. This study aimed to examine the associations of five major serum carotenoids with mortality among adults with metabolic dysfunction-associated fatty liver disease (MAFLD). METHODS AND RESULTS: This analysis included 3040 individuals with MAFLD from the Third National Health and Nutrition Examination Survey (NHANES III). All-cause and cardiovascular mortality were ascertained by linkage to the National Death Index through December 31, 2019. Cox proportional hazards regression models were employed to estimate hazard ratios (HRs) and 95% confidence intervals (CIs), and restricted cubic spline (RCS) analyses were performed to assess the linearity of the associations. During a follow-up period of 826,547 person-years, 1325 all-cause and 429 cardiovascular deaths occurred. For all-cause mortality, compared with those in the lowest quartiles, the multivariable-adjusted HRs (95% CIs) in the highest quartiles were 0.63 (0.49-0.81) for α-carotene; 0.65 (0.52-0.80) for ß-carotene; 0.64 (0.51-0.81) for ß-cryptoxanthin; 0.73 (0.56-0.95) for lycopene; and 0.69 (0.52-0.91) for lutein/zeaxanthin. For cardiovascular mortality, the multivariable-adjusted HRs (95% CIs) in the highest quartiles were 0.51 (0.33-0.78) for α-carotene; 0.54 (0.35-0.82) for ß-carotene; 0.52 (0.34-0.80) for ß-cryptoxanthin; 0.63 (0.44-0.90) for lycopene; and 0.62 (0.39-0.99) for lutein/zeaxanthin. Besides, serum α-carotene, ß-cryptoxanthin, and lycopene exhibited linear correlations with all-cause mortality in MAFLD adults, and four serum carotenoids, except ß-carotene, were linearly correlated with cardiovascular mortality. CONCLUSIONS: Lower serum α-carotene, ß-carotene, ß-cryptoxanthin, lycopene, and lutein/zeaxanthin concentrations were associated with higher risk of all-cause and cardiovascular mortality in US adults with MAFLD.

Lutein, zeaxanthin, and meso-zeaxanthin supplementation attenuates inflammatory cytokines and markers of oxidative cardiovascular processes in humans.

BACKGROUND AND AIMS: Systemic inflammation and oxidation are primary contributors to the development of atherosclerosis. Oxidation of low-density lipoprotein (LDL) particles within the vascular endothelium has been hypothesized to be an initial step in the formation of atherosclerotic plaques, with inflammatory cytokines serving as the signaling mechanism for concomitant macrophage activation. Supplementation with the antioxidative macular xanthophylls (lutein [L], zeaxanthin [Z], and meso-zeaxanthin [MZ]) has been shown to aid in the reduction of inflammatory physiologic responses; therefore, we hypothesized that in our study population, supplementation with these xanthophylls would facilitate a systemic reduction in markers of inflammation and cardiovascular lipid oxidation. METHODS AND RESULTS: In this double-blind placebo-controlled supplementation study, participants were randomly allocated to receive the active intervention containing L (10 mg) + MZ (10 mg) + Z (2 mg) or placebo (containing sunflower oil). Serum concentrations of carotenoids (assessed by HPLC), inflammatory cytokines (IL-6, IL-1ß, TNF-α) and oxidized LDL (OxLDL; by solid-phase sandwich ELISA) were measured at baseline and at 6-months. Results showed that over the supplementation period, compared to placebo, the active group demonstrated statistically significant increases in serum concentrations of L, Z, & MZ (p < 0.05), reductions in inflammatory cytokines IL-1ß (p < 0.001) and TNF-α (p = 0.003), as well as a corresponding reduction in serum OxLDL (p = 0.009). CONCLUSIONS: Our data show that L, Z, & MZ supplementation results in decreased serum IL-1ß, TNF-α, and OxLDL. This suggests that these carotenoids are acting systemically to attenuate oxidative lipid products and inflammation, thus reducing their contribution to atherosclerotic plaque formation.

Differential Performance of Xanthophylls in Combination with Phenol Classes against H2O2-Induced Oxidative Stress: An In Vitro Analysis Using Retinal Pigment Epithelial Cells.

SCOPE: Xanthophylls, vital for ocular defense against blue light and reactive oxygen species, are prone to oxidative degradation; however, they may be regenerated antioxidant-rich plant phenols. Despite certain in vitro evidence, clinical studies show inconsistent findings and this may be due to varying phenolic reduction potentials. Therefore, the current study aims to investigate the ocular protective effect of various plant phenols combined with xanthophyll. METHODS AND RESULTS: Human retinal pigment epithelial cells (ARPE-19) are subjected to oxidative stress induced by hydrogen peroxide (H2O2) after xanthophyll and phenol pretreatment. Assessments include xanthophyll uptake, total antioxidant capacity, cell viability, intracellular reactive oxygen species levels, apoptosis, phagocytosis, and vascular endothelial growth factor formation. The study finds that while the combination of lutein with phenols does not show significant protective effects compared to lutein-only, zeaxanthin combined with phenols exhibits enhanced protection compared to both the zeaxanthin-only and control groups. CONCLUSION: The research reveals the complex relationship between xanthophylls and phenols, suggesting that the advantageous effects of their combination might vary among different xanthophylls. Caution is necessary when applying molecular theories to ocular health, and this necessitates further research, serving as a basis for proposing clinical trials to evaluate the efficacy of specific xanthophyll and phenol combinations.

Lutein Modulates Cellular Functionalities and Regulates NLRP3 Inflammasome in a H2O2-Challenged Three-Dimensional Retinal Pigment Epithelium Model.

Excessive hydrogen peroxide (H2O2) generated during retinal cell metabolic activity could lead to oxidative degeneration of retinal pigment epithelium (RPE) tissue, a specific pathological process implicated in various retinal diseases resulting in blindness, which can be mitigated by taking dietary antioxidants to prevent inflammation and impaired cellular dysfunction. This study tested the hypothesis that damages induced by oxidative stresses can be mitigated by lutein in a H2O2-challenged model, which was based on an ARPE-19 cell monolayer cultured on three-dimensional (3D)-printed fibrous scaffolds. Pretreating these models with lutein (0.5 µM) for 24 h can significantly lower the oxidative stress and maintain phagocytosis and barrier function. Moreover, lutein can modulate the NLRP3 inflammasome, leading to a ∼40% decrease in the pro-inflammatory cytokine (IL-1ß and IL-18) levels. Collectively, this study suggests that the 3D RPE model is an effective tool to examine the capability of lutein to modulate cellular functionalities and regulate NLRP3 inflammation.

Construction of fatty acid-ovalbumin binary complexes to improve the water dispersibility, thermal/digestive stability and bioaccessibility of lutein: A comparative study of different fatty acids.

Lipids are increasingly being incorporated into delivery systems due to their ability to facilitate intestinal absorption of lipid-soluble nutrients through molecular solubilization and micellization. In this work, self-assembled complexes of ovalbumin (OVA) and nine dietary fatty acids (FAs) were constructed to improve the processability and absorbability of lutein (LUT). Results showed that all FAs could form stable hydrophilic particles with OVA under the optimized ultrasound-coupled pH conditions. Fourier infrared spectroscopy and transmission electron microscopy analysis showed that these binary complexes effectively encapsulated LUT with an encapsulation rate > 90.0 %. Stability experiments showed that these complexes protected LUT well, which could improve thermal stability and in vitro digestive stability by 1.66-3.58-fold and 1.27-2.74-fold, respectively. Besides, the bioaccessibility of LUT was also enhanced by 7.16-24.99-fold. The chain length and saturation of FAs affected the stability and absorption of LUT. Therefore, these results provided some reference for the selection of FAs for efficient delivery of lipid-soluble nutrients.

Lutein, a carotenoid found in numerous plants and the human eye, demonstrates the capacity to bundle collagen fibrils.

Collagen fibrils serve as the building blocks of the extracellular matrix, providing a resilient and structural framework for tissues. However, the bundling of collagen fibrils is of paramount importance in maintaining the structural integrity and functionality of various tissues in the human body. In this scenario, there is limited exploration of molecules that promote the bundling of collagen fibrils. Investigating the interactions of well-known carotenoids, commonly associated with ocular health, particularly in the retina, with collagen presents a novel and significant area of study. Here, we studied the influence of lutein, a well-known carotenoid present in many plant tissues and has several biological properties, on the structure, thermal stability, self-assembly, and fibrillation of collagen. Fibrillation kinetics and electron microscopic analyses indicated that lutein did not interfere with fibrillation process of collagen, whereas it enhances the lateral fusion of collagen fibrils leading to the formation of compact bundles of thick fibrils under physiological conditions. The hydrophobic and hydrogen bonding interactions between lutein and collagen fibrils are most likely the cause of the bundling of the fibrils. This study establishes the first investigation of collagen-carotenoid interactions, showcasing the unique property of lutein in bundling collagen fibrils, which may find potential application in tissue engineering.

Unveiling the potential of Pseudococcomyxa simplex: a stepwise extraction for cosmetic applications.

Microalgae are gaining attention as they are considered green fabrics able to synthesize many bioactive metabolites, with unique biological activities. However, their use at an industrial scale is still a challenge because of the high costs related to upstream and downstream processes. Here, a biorefinery approach was proposed, starting from the biomass of the green microalga Pseudococcomyxa simplex for the extraction of two classes of molecules with a potential use in the cosmetic industry. Carotenoids were extracted first by an ultrasound-assisted extraction, and then, from the residual biomass, lipids were obtained by a conventional extraction. The chemical characterization of the ethanol extract indicated lutein, a biosynthetic derivative of α-carotene, as the most abundant carotenoid. The extract was found to be fully biocompatible on a cell-based model, active as antioxidant and with an in vitro anti-aging property. In particular, the lutein-enriched fraction was able to activate Nrf2 pathway, which plays a key role also in aging process. Finally, lipids were isolated from the residual biomass and the isolated fatty acids fraction was composed by palmitic and stearic acids. These molecules, fully biocompatible, can find application as emulsifiers and softener agents in cosmetic formulations. Thus, an untapped microalgal species can represent a sustainable source for cosmeceutical formulations. KEY POINTS: • Pseudococcomyxa simplex has been explored in a cascade approach. • Lutein is the main extracted carotenoid and has antioxidant and anti-aging activity. • Fatty acids are mainly composed of palmitic and stearic acids.