Management of oral leukoplakia—a potentially malignant disorder—is currently not evidence‐based. Of the few randomized trials that have been reported, most have negative data. Therefore, a ...multi‐centre, randomized, double‐blind controlled trial (RCT) was undertaken to evaluate the use of low‐dose beta‐carotene combined with vitamin C supplements for the treatment and to prevent malignant transformation of oral leukoplakia. 46 Japanese participants with oral leukoplakia were allocated randomly either to an experimental arm (10 mg day−1 of beta‐carotene and 500 mg day−1 of vitamin C) or placebo arm (50 mg day−1 of vitamin C). Current or ex‐smokers within 3 months of cessation were excluded. The supplements were continued over a period of 1 year. The primary endpoint was clinical remission at 1‐year and the likelihood of malignant transformation during a 5‐year follow‐up period as a secondary endpoint. The overall clinical response rate in the experimental arm was 17.4% (4/23) and 4.3% (1/23) in the placebo arm (p = 0.346). During the median 60‐month follow‐up period, two subjects in the experimental arm and three in the control arm developed oral cancer. Under the intention‐to‐treat principle, relative risk by supplementing with beta‐carotene and vitamin C was 0.77 (95%CI: 0.28–1.89) (p = 0.580) by the Cox proportional hazards model. No unfavorable side‐effects were noted. Beta‐carotene (10 mg day−1) and vitamin C were neither effective for clinical remission, nor for protection against the development of cancer. Data from this RCT does not support the hypothesis that chemoprevention with this treatment is effective for oral leukoplakia.
What's new?
The randomized controlled trial presented here used β‐carotene among a non/ex‐smoking group of patients with oral leukoplakia‐a potentially malignant disorder whose management is currently not evidence based. The β‐carotene dose was lower than doses used in earlier studies that may carry an increased risk of cancer in the study population. The mean follow‐up period of 60 months allowed the inclusion of malignant transformation in the data analysis, unlike in earlier publications. The negative outcome from this trial strengthens previous conclusion that β‐carotene, even in combination with an additional antioxidant, does not provide a significant benefit to the population studied.
The genus Dunaliella belongs to the division Chlorophyta and is known for its ability to survive in highly saline environments. Dunaliella is an important source of carotenoids, especially ...beta-carotene and has a wide range of applications. In this study, we aimed to isolate and identify Dunaliella strains from active and abandoned saltworks in Greece. Four seasonal samplings were carried out in seven active saltworks and two samplings were performed in an abandoned saltwork throughout the year 2020. Strains were characterized based on their morphological and phylogenetic traits, whilst their beta-carotene potential were evaluated. Fifteen (15) Dunaliella strains were isolated and classified into nine species based on morphological and morphometrical features. The isolated strains were assigned to different species such as D. parva, D. granulata, D. minuta, D. terricola, D. asymmetrica, D. bioculata, D. viridis, D. minutissima, and D. polymorpha. The results of the phylogenetic analysis indicate the formation of distinct clades among different Dunaliella species and suggest that morphological and morphometrical features may not always align with the phylogenetic position of species in the Dunaliella clade. Strains were found to produce a low amount of beta-carotene under default laboratory conditions. This study comprises the first phylogenetic inference of several Dunaliella species and highlights a gap on molecular data for Dunaliella spp. We provide valuable information on the diversity of Dunaliella strains in the saltworks of Greece, which can be used for further research and biotechnological applications.
•Cloud point extraction coupled to a cold column trapping system eliminates the centrifugation step.•The method is faster than ordinary cloud point extraction and uses a more moderate extraction ...conditions.•The method is appropriate for quantitation of thermally unstable compounds such as β-carotene.•The method is semi-automated and is simply coupled to UV–Vis Spectrophotometry.
Cloud point extraction with cold column trapping (CPE-CCT) was used for the rapid preconcentration and UV–Vis spectroscopy of beta-carotene in fruit juice samples. A central composite design was employed to optimize parameters such as pH, incubation time, cloud point temperature and surfactant concentration. A detection limit of 0.01 mg/L of beta-carotene (3SB/m), a coefficient of determination of 0.998 and a linear range of 0.04–10 mg/L were obtained. The CPE-CCT method was confirmed in comparison with the corresponding direct HPLC standard method. A simple, portable and cost-effective device was also utilized. Owing to eliminating centrifugation, the conditions of CPE-CCT were more moderate and its sample handling easier compared to conventional CPE.
•The whey protein isolate fibrils (WPIF) were prepared through heating at pH 2.0.•Fibrils improved the stability of β-carotene at pH 3.2.•WPIF interacted with β-carotene was by hydrophobic ...interactions and hydrogen bond.•β-carotene showed better bioavailability through the formation of WPIF/β-carotene complexes.
β-Carotene (BC) exhibits several bioactive properties, but its application is restrained due to the unstability and low biological availability. In this study, protein fibrils were prepared from whey protein isolate fibrils (WPIF), which were used as carriers to protect and deliver BC. With the extension of heating time, the molecular weight of WPI decreased gradually. WPI was hydrolyzed into peptides which self-assembled into WPIF, resulting in significant changes in secondary structure, zeta-potential, viscosity and, antioxidant capacity. The main interactions between WPIF and BC were hydrogen bonding and hydrophobic interaction. The encapsulation efficiency of WPIF24 was increased from 76.55% to 92.11% compared to that of untreated WPI. Moreover, the simulated gastrointestinal release showed that the cumulative release of BC encapsulated by WPIF24 reached the maximum in the simulated intestine. Therefore, WPIF could be a potential delivery system for water-insoluble bioactive compounds with enhanced encapsulation efficiency and protection effect.
Previously, it was shown that catechin–egg white protein (CT-EWP) conjugates were effective antioxidant emulsifiers that could form and stabilize emulsions, and also inhibit the degradation of ...encapsulated carotenoids. The objective of the current study was to evaluate the impact of conjugation on the in vitro bioavailability, cellular antioxidant activity, and cytotoxicity of β-carotene-loaded emulsions. Lipid droplets coated with EWP or with CT-EWP conjugates exhibited quite similar behavior when they were passed through a simulated gastrointestinal tract. The β-carotene encapsulated in emulsions stabilized by CT-EWP conjugates exhibited a higher overall in vitro bioavailability, which was attributed to a greater stability of the carotenoids to chemical transformation. The emulsions stabilized by CT-EWP conjugates also exhibited greater ability in inhibiting oxidation in a cell-based assay (dichlorofluorescein diacetate). Cytotoxicity analysis suggested that β-carotene emulsions stabilized by CT-EWP conjugates only exhibited a slight cytotoxicity when used at high concentrations. These results suggest that CT-EWP conjugates can be used to formulate emulsion-based delivery systems for chemically labile hydrophobic bioactives with enhanced antioxidant activity and bioavailability.
MAIN CONCLUSION : High levels of β-carotene, lycopene, and the rare γ-carotene occur predominantly lipid-dissolved in the chromoplasts of peach palm fruits. First proof of their absorption from these ...fruits is reported. The structural diversity, the physical deposition state in planta, and the human bioavailability of carotenoids from the edible fruits of diverse orange and yellow-colored peach palm (Bactris gasipaes Kunth) varieties were investigated. HPLC–PDA–MSⁿ revealed a broad range of carotenes, reaching total carotenoid levels from 0.7 to 13.9 mg/100 g FW. Besides the predominant (all-E)-β-carotene (0.4–5.4 mg/100 g FW), two (Z)-isomers of γ-carotene (0.1–3.9 mg/100 g FW), and one (Z)-lycopene isomer (0.04–0.83 mg/100 g FW) prevailed. Approximately 89–94 % of total carotenoid content pertained to provitamin A carotenoids with retinol activity equivalents ranging from 37 to 609 µg/100 g FW. The physical deposition state of these carotenoids in planta was investigated using light, transmission electron, and scanning electron microscopy. The plastids found in both orange and yellow-colored fruit mesocarps were amylo-chromoplasts of the globular type, containing carotenoids predominantly in a lipid-dissolved form. The hypothesis of lipid-dissolved carotenoids was supported by simple solubility estimations based on carotenoid and lipid contents of the fruit mesocarp. In our study, we report first results on the human bioavailability of γ-carotene, β-carotene, and lycopene from peach palm fruit, particularly proving the post-prandial absorption of the rarely occurring γ-carotene. Since the physical state of carotenoid deposition has been shown to be decisive for carotenoid bioavailability, lipid-dissolved carotenoids in peach palm fruits are expected to be highly bioavailable, however, further studies are required.
Keywords beta-Carotene; Pickering emulsions; Complex nanogels; Gastrointestinal digestion; Bioaccessibility Highlights * Pickering emulsions were found to be stable under thermal treatment. * ...Pickering emulsions protected beta-carotene from chemical degradation during storage. * Lipid oxidation rate could be delayed by Pickering emulsions. * The bioaccessibility of beta-carotene in Pickering emulsions was higher than bulk oil. beta-Carotene was encapsulated in the Pickering emulsions stabilized by chitosan hydrochloride -- carboxymethyl starch (CHC-CMS) nanogels. During ultraviolet radiation and storage, the retention of beta-carotene in Pickering emulsions was higher than that of other formulations, such as Tween 80 stabilized emulsions (TEs) and bulk oil. The Pickering emulsions were found to be stable during thermal treatment. Meanwhile, lipid oxidation was delayed in Pickering emulsions compared to TEs and bulk oil. The vitro digestion results suggested that the free fatty acids (FFA) released were below 30% for all Pickering emulsions, which indicated that a physical barrier was formed by CHC-CMS nanogels to restrain the lipid hydrolysis. The bioaccessibility of beta-carotene in Pickering emulsions was higher than that in bulk oil. This research helped establish a connection between the physicochemical properties of CHC-CMS stabilized Pickering emulsions with their applications in the protection effect and oral delivery of bioactive compounds. Author Affiliation: (a) Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui 230009, PR China (b) Department of Food and Bioengineering, Zhengzhou University of Light Industry, No. 136 Science Avenue, Zhengzhou, Henan 450000, PR China (c) School of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, Shandong, PR China (d) School of Food and Biological Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui 230009, PR China (e) State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha 410125, PR China (f) Technology Extension Service Center for Forest and Fruit Industries in Turpan, Turpan, Xinjiang 838000, PR China * Corresponding author at: Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui 230009, PR China. Article History: Received 27 June 2019; Revised 22 January 2020; Accepted 22 January 2020 (footnote)1 These authors contributed equally to this work. Byline: Xiao-Min Li (a,d,1), Xuehong Li (b,1), Zhengzong Wu (c), Ying Wang (a,d), Jie-Shun Cheng (a,d), Ting Wang (f), Bao Zhang baoz@hfut.edu.cn (a,d,e,*)
Background:
The study aimed to identify 2 beta-carotene 15,15′-monooxygenase (BCMO1) mutations, namely R267S and A379V, and determine their association with vitamin A status among Filipinos 6 to 19 ...years old respondents of the 2013 Philippine National Nutrition Survey living in the National Capital Region.
Materials and Methods:
This study followed cross-sectional design. Whole blood specimen was collected in the morning and was used as source of genomic DNA and serum for retinol concentration determination. Fisher exact test was performed to determine whether genotype frequencies were associated to retinol concentrations/vitamin A deficiency status. A level of P < .05 was identified as significant.
Results:
A total of 693 Filipino children and adolescents were included. Of the 693, there were at least 7.6% who bear the combined mutations for R267S + A379V. Association analysis showed that an inverse relationship exists between the A379V TT variant and vitamin A status, although the exact role of these identified polymorphisms on retinol/carotenoid metabolism need to be confirmed in dedicated functional studies.
Conclusion:
This study has identified for the first time the presence of 2 nonsynonymous genetic variants/mutations in the coding region of BCMO1 gene. Interestingly, one of these 2 variants, the A379V T, was found to be associated with vitamin A status. It is, therefore, warranted to investigate the role of BCMO1 variants for the success of supplementation programs and fortification efforts among vulnerable populations in this region. Genetic variability should be considered for future provitamin A supplementation recommendations among children and adolescents in the Philippines.
β-Carotene (BC) serves as an important source of provitamin A and natural edible pigment, but the application is limited because of its instability and low oral-bioavailability. A tea ...polyphenols-β-carotene (TP-BC) oil-in-water (O/W) nanoemulsion was prepared with the core oil phase containing BC and the water phase containing TP. During storage at three different temperatures (4, 25 and 35 °C), the TP-BC nanoemulsion had a better stability and higher retention rate of BC than BC nanoemulsion. An in vitro simulated digestion assay indicated that the BC recovery rates of TP-BC nanoemulsion at digestion phases I and II were significantly increased compared to the BC nanoemulsion. An in vivo absorption study showed that TP-BC nanoemulsion had higher conversion efficiency on vitamin A compared to the BC nanoemulsion. These results suggested that tea polyphenols are effective ingredients for improving the oral-bioavailability of BC.
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•Tea polyphenols β-carotene nanoemulsion were prepared by high pressure homogenization.•Tea polyphenols improved the nano-properties of β-carotene nanoemulsion during storage.•The retention rate of β-carotene in nanoemulsion was increased by tea polyphenols.•The vitamin A levels of rat liver after nanoemulsion intake was increased by tea polyphenols.
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