Antioxidant Activity Of Β-carotene Research Articles

The Effect of Multilayer Nanoemulsion on the In Vitro Digestion and Antioxidant Activity of β-Carotene.

The objectives of this study were to design multilayer oil-in-water nanoemulsions using a layer-by-layer technique to enhance the stability of β-carotene and evaluate its effect on in vitro release and antioxidant activity. To prepare β-carotene-loaded multilayer nanoemulsions (NEs), a primary NE (PRI-NE) using Tween 20 was coated with chitosan (CS) for the secondary NE (SEC-CS), and with dextran sulfate (DS) and sodium alginate (SA) for the two types of tertiary NEs (TER-DS, TER-SA). The multilayer NEs ranged in particle size from 92 to 110 nm and exhibited high entrapment efficiency (92-99%). After incubation in a simulated gastrointestinal tract model, the release rate of free fatty acids decreased slightly after coating with CS, DS, and SA. The bioaccessibility of β-carotene was 7.02% for the PRI-NE, 7.96% for the SEC-CS, 10.88% for the TER-DS, and 10.25% for the TER-SA. The 2,2-diphenyl-1-picrylhydrazyl radical scavenging abilities increased by 1.2 times for the multilayer NEs compared to the PRI-NE. In addition, the cellular antioxidant abilities improved by 1.8 times for the TER-DS (87.24%) compared to the PRI-NE (48.36%). Therefore, multilayer nanoemulsions are potentially valuable techniques to improve the stability, in vitro digestion, and antioxidant activity of β-carotene.

Improving the bioaccessibility of lipophilic ingredient in its oral intestinal delivery by ultrasound and biological cross-linker.

Great efforts have been made to improve the oral bioaccessibility of lipophilic ingredients with multi-functionalities. Achieving intestinal delivery of lipophilic ingredients and their encapsulation in micelles composed of bile salts and lipid hydrolysates (i.e. fatty acids) is critical for improving oral bioaccessibility. Therefore, oil-core microcapsules are considered ideal carriers of lipophilic ingredients. Previous studies have reported oil-core/zein-shell microcapsules constructed by a one-step anti-solvent process. Still, its efficacy as an intestinal delivery system was limited because if the porous shell structure. Zein solution was pretreated with ultrasound and tannic acid (TA) cross-linking. Composite oil-core microcapsule (COM) with a compact shell structure was successfully prepared by using modified zein solution in the anti-solvent process. Fourier-transform infrared spectroscopy and circular dichroism analyses indicated that ultrasound and TA synergistically promote the conformational transition of zein from α-helix to β-sheet and enhance the hydrophobic interactions among protein chains. The above changes contribute to the strengthen of shell zein network. Correspondingly, COM presents superior encapsulation efficiency and environmental stability over the simple oil-core microcapsule (SOM) prepared without the use of ultrasound and TA. Furthermore, antioxidant activity of β-carotene was well retained during the encapsulation process. In vitro studies indicated that COM was more resistant to digestibility and acid-induced swelling. More than 87% of β-carotene could be released in the intestine in a sustainable way. The controllable release behavior thus promoted a significant increase in bioaccessibility of β-carotene encapsulated in COM compared to SOM (85.9% versus 48.5%). The COM generated here shows potential for bioaccessibility improvement of lipophilic ingredients. © 2022 Society of Chemical Industry.

Development of dendrimer-like glucan-stabilized Pickering emulsions incorporated with β-carotene

The impact of sugary maize dendrimer-like glucan octenyl succinate (OSA-SMDG) on the storage stability and antioxidant activity of β-carotene (BC)-loaded emulsions as well as bioaccessibility were investigated. The encapsulation efficiency of β-carotene in emulsions containing 3% OSA-SMDG (3OSA-SMDG-BC) or 5% OSA-SMDG (5OSA-SMDG-BC) was 89.6% and 94.9%, respectively. The antioxidant activity of both emulsions was higher than that of pure β-carotene. During simulated digestion, the particle size of emulsions was immediately reduced, whereas zeta-potential was continuously increased in intestinal digestion. After 2 h digestion, the free fatty acids (FFA) release rate of 3OSA-SMDG-BC and 5OSA-SMDG-BC was significantly higher than that of blank emulsion. Bioaccessibility of β-carotene encapsulated in 3OSA-SMDG-BC and 5OSA-SMDG-BC was also significantly higher than that of blank emulsion. FFA release rate and β-carotene bioaccessibility of 5OSA-SMDG-BC were higher than that of 3OSA-SMDG-BC. These results demonstrated that OSA-SMDG could be used to fabricate food-grade O/W Pickering emulsion as a delivery system for bioactive compounds.

Beta-carotene exerted anti-proliferative and apoptotic effect on malignant mesothelioma cells.

High blood levels of β-carotene and increased intake in the diets are inversely proportional to incidence of many cancer types. Antioxidant activity of β-carotene was proposed to be related with its antitumor effect. Despite this plant derivative substance being sought in many cancer types, the effectiveness of β-carotene against malignant mesothelioma remained unclear. Therefore, the present study aims to explore the impact of β-carotene on cell viability, apoptosis, and oxidative stress in mesothelioma cells. Human mesothelioma cell SPC212 were treated with β-carotene (3.125-200μM) for 24, 48, 72, and 96h. Cytotoxicity was measured with the MTT assay (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide). Annexin-V/propidium iodide (PI) and caspase 3/7 biomarkers were used to identify apoptotic cells. Finally, the oxidative stress was evaluated with flow cytometry. The results of the measurements indicated a significant decline in viable mesothelioma cancer cell numbers upon β-carotene treatment in time- and concentration-dependent manner when compared to control cells. Furthermore, β-carotene treatment led to apoptosis induction according to both annexin V/PI and caspase 3/7 assays. Furthermore, β-carotene increased oxidative stress in SPC212 cells. These results show how β-carotene affects proliferative, apoptotic, and oxidative properties in SPC212 malignant pleural mesothelioma cells and provide useful insights into future studies.

Valorizing okara waste into nutritionally rich polysaccharide/protein-extracts for co-encapsulation of β-carotene and ferrous sulphate as a potential approach to tackle micronutrient malnutrition

Colossal amounts of food waste are generated and discarded daily at the expense of financial resources and at a detriment to the environment. One such food waste, okara - a soybean by-product, is valorized in this study by upcycling it into nutritional extracts for micronutrients encapsulation. Micronutrient malnutrition, particularly in the developing world, is a major public health challenge. Herein, okara extracts were obtained through a low-cost extraction process and was subsequently developed as an encapsulant material for micronutrients β-carotene, and ferrous sulphate encapsulation, using zein as an excipient. Spray-drying, as a scalable technique, was employed to produce variousformulations which were assessed forrelease profiles, shelf-life, β-carotene antioxidant activity and cell cytotoxicity. Finally, an optimized dual-micronutrient formulation displayed a sequential releasewith ferrous sulphate releasing in simulated gastric fluid, and β-carotene releasing predominantly in simulated intestinal fluid. This sequential release profile favors the absorption of both the micronutrients and could potentially enhance their bioavailability.

Chemical Composition, Antioxidant and Antimicrobial Activities of the Essential Oils from Rhizomes and Leaves of Alpinia conchigera Griff. (Zingiberaceae)

This study was conducted to assess the potential of essential oils isolated from rhizomes and leaves of Alpinia conchigera as a source of bioactive compounds through the characterization of its chemical composition, antioxidant, and anti-microbial activities. Essential oils (EOs) from the leaves and rhizomes of this species were isolated using the hydrodistillation method. The chemical compositions of EOs were analyzed by using GC and GC-MS. The major compound of the rhizome EO was eucalyptol (60.58 %), whereas the most abundant compound in the leaf EO was β-bisabolene (46.70 %). The rhizome EO contained the most abundant polyphenolic compounds that possessed higher antioxidant activities compared to leaf EO and the reference antioxidant agent butylated hydroxytoluene (BHT). In addition, there exist a positive correlation between total phenolic content and antioxidant activities using DPPH (R2= 0.7634, p < 0.05) and β-carotene antioxidant activity (R2 = 0.6865, p < 0.05). Disc diffusion assay of the essential oils indicated that the rhizome oil possessed moderate inhibitory activity against all tested bacteria and fungi, whereas leaf EO inhibited only Gram-positive bacteria. The results indicated the potential of these EOs to exert beneficial antibacterial and antifungal effects and could serve as a promising natural cheap source of antioxidants that could be used in the food and pharmaceutical industries.

Microwave-assisted extraction as an advanced technique for optimisation of limonoid yields and antioxidant potential from Trichilia roka (Meliaceae)

Response surface methodology (RSM) was applied to predict optimum conditions for microwave-assisted extraction (MAE) of total limonoid (TL) and antioxidant potential investigation from Trichilia roka (Chiov) root bark. A central composite design methodology (CCDM) was used to minor the effect of the independent variables such as irradiation time (X1), irradiation power (X2), liquid-to-solid ratio (X3) and methanol polarity (X4) on the dependent variables namely total limonoid (TL), total polyphenol (TPP), DPPH radical scavenging activity and β-carotene antioxidant activity (AOA). The optimal combined conditions for extracting maximum TL (116 ​mg RUBE/gDW), TPP (12.5 ​g GAE/100gDW) and antioxidant activity (DPPH 90.1%; AOA 90.5%) were irradiation time 80 ​s, irradiation power 600 ​W, liquid to solid ratio 0.6/20 ​mL/g and methanol concentration 40%. All the factors significantly (p ​< ​0.01) influenced the responses, the variations from the independent variables corresponding significantly to the predicted polynomial model and the maximum values estimated at the predicted optimal condition were in good agreement with experimental value. In conclusion MAE of antioxidant compounds from Trichilia roka (Chiov) root bark is highly influenced by equipment parameters of functioning (microwave irradiation time and power) as well as the solvent (liquid to solid ratio and methanol concentration), following a second degree polynomial model.

Bioaccessibility and Antioxidant Activity of β-Carotene Loaded Nanostructured Lipid Carrier (NLC) from Binary Mixtures of Palm Stearin and Palm Olein

Bioaccessibility and Antioxidant Activity of β-Carotene Loaded Nanostructured Lipid Carrier (NLC) from Binary Mixtures of Palm Stearin and Palm Olein

Microalgae based biorefinery: Assessment of wild fresh water microalgal isolate for simultaneous biodiesel and β-carotene production

Microalgal biorefineries that produce biofuels and value-added products have been extensively investigated in recent years. This study has assessed potential of freshwater microalga for lipids and β-carotene production. The phylogenetic positioning of isolated strain by 18S rRNA sequence analysis revealed that it belonged to genus Scenedesmus. The strain was named Tetradesmus obliquus SGM19. Optimum growth conditions (nitrogen source, NaNO3 = 1.5 g/L; photoperiod 12L:12D) yielded biomass concentration = 2.5 g/L, β-carotene yield = 0.67 mg/g dry biomass, lipid content = 28.5 wt%. Antioxidant activity of β-carotene (measured using DPPH assay) was 69%. ~79% constituents of lipids could be identified from GC–MS analysis of biodiesel synthesized from the lipids. Major fatty acids present in the lipids were palmitic, heptadecanoic, linoleic, linolenic and arachidic acids. Properties of biodiesel estimated from FAME composition (e.g. cetane number = 48.59) are within limits of ASTM D6751 and EN 14214 standards.

Citric acid cross-linked zein microcapsule as an efficient intestine-specific oral delivery system for lipophilic bioactive compound

To improve the stability of zein core-shell structure microcapsule and realize intestine-specific release of lipophilic bioactive compounds, the β-carotene-loaded microcapsule was prepared by zein cross-linked with citric acid (CA) for the first time. The antioxidant activity of β-carotene was not affected by preparation process. Compared to uncross-linked microcapsule (UCM), the CA cross-linked microcapsule (CCM) had higher β-carotene encapsulation efficiency (94.4% vs. 91.4%), greater shell thickness (161 nm vs. 140 nm) and denser shell structure. Additionally, the CCM had better stability under thermal, freeze-thaw and ionic strength treatments. The fourier transform infrared spectra (FTIR) and circular dichroism (CD) analysis showed that there existed hydrogen bonding and interactions between zein and CA, and differential scanning calorimetry (DSC) and X-ray diffraction (XRD) data revealed the thermal stability and crystallinity intensity of zein/CA complex were improved. The CCM was more stable in simulated gastric fluids and β-carotene bioaccessibility was significantly improved in simulated intestine fluids (72.4% vs. 48.5%).

Antioxidant Properties of β-Carotene Isomers and Their Role in Photosystems: Insights from Ab Initio Simulations

In this work we investigate the effect of cis isomerizations and conformational changes on the antioxidant activity of β-carotene, one of the most important pigments in nature. The electrodonating (ω(-)) and electroaccepting (ω(+)) powers of the most relevant isomers of β-carotene are first evaluated in polar and nonpolar solvents using density functional theory (DFT), and these quantities are then used to establish an antioxidant scale of the isomers. The electrodonating power, which is directly related to the antioxidant activity, is shown to provide a very good correlation with the experimental data. Next, we compute the intermediate twisted structures of the β-carotene isomers generated by partial rotation of every single bond in the polyenic chain. The electrodonating and electroaccepting powers are evaluated for each of these intermediate structures along with their maximum absorption wavelengths, which are computed using time-dependent DFT (TD-DFT). The trends observed for both the electrodonating power and the maximum absorption wavelength can be rationalized in terms of the effective conjugated chain length of the structure resulting from single bond rotations. The results obtained are used to analyze the conformational distribution of β-carotene in the well-resolved photosystem I (PS-I) of purple cyanobacteria. It is then shown that the isomers present in this photosystem are those having the lowest calculated relative energies and that those with enhanced antioxidant activity are preferentially located in the inner core of the protein complex.

Beta-carotene suppression of benzophenone-sensitized lipid peroxidation in hexane through additional chain-breaking activities

The aim of this work is to estimate the antioxidant activity of β-carotene in the presence of two different mixtures of phospholipids in hexane solution, under continuous UV-irradiation from three different ranges (UV-A, UV-B, and UV-C). β-Carotene is employed to control lipid peroxidation process generated by UV-irradiation, in the presence and in the absence of selected photosensitizer, benzophenone, by scavenging the involved, created free radicals. The results show that β-carotene undergoes to a substantial, probably structural dependent destruction (bleaching), highly dependent on UV-photons energy input, more expressed in the presence than in the absence of benzophenone. The additional bleaching is synchronized with the further increase in β-carotene antioxidant activity in the presence of benzophenone, implying the same cause: increase in (phospholipids peroxidation) chain-breaking activities.

Effects of β-carotene on antioxidant enzyme activity, intracellular reactive oxygen and membrane integrity within post confluent Caco-2 intestinal cells

As encountered with a plethora of other natural products, the antioxidant activity of β-carotene has been proposed as one of the mechanisms by which diets rich in this pro-vitamin A active carotenoid apparently afford chemoprevention. Here, we report the ability of β-carotene to alter endogenous reactive oxygen levels and antioxidant defences within non-stressed ‘differentiated’ monolayers of an intestinal epithelial cell line (Caco-2) and to subsequently effect resistance to general oxidative insult. The differentiated monolayers efficiently absorbed β-carotene. Between 3 and 8 days post confluence, cultures exhibited a progressive increase in antioxidant enzyme activity and a corresponding reduction to intracellular ROS levels. The profile for antioxidant enzyme activity was unaffected by sustained daily supplementation with β-carotene. However, after two daily treatments with 50 μM β-carotene intracellular ROS levels were significantly reduced and there was a trend towards reduced intracellular ROS within monolayers subject to five daily treatments with 0.5 and 5 μM β-carotene. Prolonged supplementation with 0.1 and 0.5 μM β-carotene or short supplementation periods with 5 and 50 μM β-carotene did not alter susceptibility to H 2O 2. However, cultures treated daily between 3 and 8 days post confluence with 5 or 50 μM β-carotene exhibited enhanced LDH release, increased non-adherence and enhanced Trypan blue staining when challenged with 10 mM H 2O 2. In the absence of H 2O 2, the β-carotene treatments were not overtly toxic to the monolayers. These results indicate that β-carotene does not enhance antioxidant defences within Caco-2 monolayers. The enhancement of H 2O 2 toxicity by persistent, high doses of β-carotene may contribute to the failure of this carotenoid to protect high risk individuals from certain degenerative conditions.

Radioprotection of β-carotene evaluated on mouse somatic and germ cells

In the present paper, the protective effect of β-carotene was evaluated after whole body exposure of mice to 2 Gy of X-rays. Splenocytes, reticulocytes, bone marrow cells and spermatids were evaluated for the frequency of micronuclei (MN) induced by X-rays. Mice were treated (gavage) with β-carotene (10,25 and 50 mg/kg b.w.) for 5 consecutive days and, 4 h after the last treatment, the animals were irradiated. The results obtained showed different frequencies of X-ray-induced-MN between different cell populations analysed and also different response of these cells to the β-carotene treatment. The radioprotective effect of β-carotene was observed in splenocytes, reticulocytes, and spermatids but not in bone marrow cells. No dose-response relationship for β-carotene was detected. The time of sampling, the sensitivity of the cells as well as the antioxidant activity of β-carotene are discussed as important factors for the radioprotective action of this provitamin.

The effect of fatty acid unsaturation on the antioxidant activity of β-carotene and α-tocopherol in hexane solutions

The effect of fatty acid unsaturation on the antioxidant ability of β-carotene and α-tocopherol to inhibit azobisisobutyronitrile (AIBN)-induced malondialdehyde (MDA) formation is investigated in a hexane solution. A positive correlation is shown between the fatty acid unsaturation and MDA production in homogeneous solutions. Both β-carotene and α-tocopherol act as chain-breaking antioxidants in our model, effectively suppressing AIBN-induced MDA formation. When α-tocopherol is added to fatty acid solutions, a lag phase of about 30 min is observed and a propagation phase is produced at a rate dependent on the degree of unsaturation and similar to that observed in the absence of the antioxidant. A specific inhibition of initiation phase by α-tocopherol is confirmed by its total consumption after 30 min of incubation with AIBN. On the other hand, when β-carotene is added, a lag period is not observed and the inhibition of propagation phase progressively increases in relation to the degree of fatty acid unsaturation. These data present different antioxidant roles for β-carotene and α-tocopherol in AIBN-induced lipid peroxidation and suggest that β-carotene can be a very effective antioxidant in highly unsaturated membranes, such as those enriched with n-3 polyunsaturated fatty acids (PUFA).