Β-carotene Degradation Research Articles

Enrichment of White Chocolate with Microencapsulated β-Carotene: Impact on Quality Characteristics and β-Carotene Stability during Storage.

This study developed functional white chocolate enriched with free (WC-F) and encapsulated β-carotene using whey protein isolate (WPI) and pullulan (PUL) blends through spray drying (WC-SP), freeze drying (WC-LP), and coaxial electrospinning (WC-EL). The thermal properties, rheological properties, hardness, and color of the chocolates were evaluated, and the stability of β-carotene was monitored over 4 months at 25 °C. No significant differences were found in melting profile temperatures among samples; however, WC-LP and WC-EL exhibited higher melting energies (30.88 J/g and 16.00 J/g) compared to the control (12.42 J/g). WC-F and WC-SP showed rheological behaviors similar to those of the control, while WC-LP and WC-EL displayed altered flow characteristics. Hardness was unaffected in WC-F and WC-SP (7.77 N/mm2 and 9.36 N/mm2), increased slightly in WC-LP (10.28 N/mm2), and decreased significantly in WC-EL (5.89 N/mm2). Over storage, melting point, rheological parameters, and hardness increased slightly, while color parameters decreased. β-carotene degradation followed a first-order reaction model, with degradation rate constants (k) of 0.0066 day-1 for WC-SP, 0.0094 day-1 for WC-LP, and 0.0080 day-1 for WC-EL, compared to 0.0164 day-1 for WC-F. WC-SP provided the best β-carotene retention, extending the half-life period by 2 times compared to WC-F (126.04 days vs. 61.95 days). Practical implications: The findings suggest that WC-SP, with its superior β-carotene stability, is particularly suitable for the development of functional confectionery products with extended shelf life, offering potential benefits in industrial applications where product stability is crucial. Future research directions: Further studies could explore the incorporation of additional bioactive compounds in white chocolate using similar encapsulation methods, as well as consumer acceptance and sensory evaluation of these enriched products.

Encapsulation of β-carotene in Pickering emulsions stabilized by self-aggregated chitosan nanoparticles: Factors affecting β-carotene stability

For conventional emulsions used to encapsulate easily degradable bioactive compounds, achieving small droplet size and high encapsulation capacity is a challenging. Pickering emulsions stabilized by self-aggregated chitosan particles may offer high encapsulation efficiency due to the robust mechanical barrier formed by solid particles adsorbed at the oil-water interface. Therefore, the effects of pH, chitosan concentration, oil volume fraction, homogenization pressure, and homogenization cycle on the stability of chitosan Pickering emulsions and the degradation of β-carotene were investigated. Effective interfacial adsorption of chitosan nanoparticles and moderate homogenization intensity facilitated the formation of small emulsion droplets. Unlike conventional emulsions, chitosan Pickering emulsions with smaller droplets provided enhanced protection for β-carotene. This enhancement was primarily attributed to the improved interfacial coverage of chitosan nanoparticles with smaller droplet sizes, which was advantageous for β-carotene protection. The optimal conditions for preparing β-carotene-loaded chitosan Pickering emulsions were as follows: pH 6.5, chitosan concentration of 1.0 wt%, oil volume fraction of 20 %, homogenization pressure of 90 MPa, and 6 homogenization cycles. These findings indicate that chitosan Pickering emulsions are well-suited for encapsulating β-carotene with both small droplet size and high encapsulation efficiency.

NinaB and BCO Collaboratively Participate in the β-Carotene Catabolism in Crustaceans: A Case Study on Chinese Mitten Crab Eriocheir sinensis.

Carotenoid cleavage oxygenases can cleave carotenoids into a range of biologically important products. Carotenoid isomerooxygenase (NinaB) and β, β-carotene 15, 15'-monooxygenase (BCO1) are two important oxygenases. In order to understand the roles that both oxygenases exert in crustaceans, we first investigated NinaB-like (EsNinaBl) and BCO1-like (EsBCO1l) within the genome of Chinese mitten crab (Eriocheir sinensis). Their functions were then deciphered through an analysis of their expression patterns, an in vitro β-carotene degradation assay, and RNA interference. The results showed that both EsNinaBl and EsBCO1l contain an RPE65 domain and exhibit high levels of expression in the hepatopancreas. During the molting stage, EsNinaBl exhibited significant upregulation in stage C, whereas EsBCO1l showed significantly higher expression levels at stage AB. Moreover, dietary supplementation with β-carotene resulted in a notable increase in the expression of EsNinaBl and EsBCO1l in the hepatopancreas. Further functional assays showed that the EsNinaBl expressed in E. coli underwent significant changes in its color, from orange to light; in addition, its β-carotene cleavage was higher than that of EsBCO1l. After the knockdown of EsNinaBl or EsBCO1l in juvenile E. sinensis, the expression levels of both genes were significantly decreased in the hepatopancreas, accompanied by a notable increase in the redness (a*) values. Furthermore, a significant increase in the β-carotene content was observed in the hepatopancreas when EsNinaBl-mRNA was suppressed, which suggests that EsNinaBl plays an important role in carotenoid cleavage, specifically β-carotene. In conclusion, our findings suggest that EsNinaBl and EsBCO1l may exhibit functional co-expression and play a crucial role in carotenoid cleavage in crabs.

Chemical, antioxidant, and antifungal analysis of oregano and thyme essential oils from Ecuador: Effect of thyme against Lasiodiplodia theobromae and its application in banana rot

The objective of this study was to evaluate the antioxidant capacity by spectrophotometric methods, the in vitro and in vivo antifungal effect against Lasiodiplodia theobromae and the constitution of the essential oils (EO) of oregano and thyme in comparison with their commercial counterparts. The results showed by the EOs of extracted thyme (T-EO), commercial thyme (CT-EO), extracted oregano (O-EO) and commercial oregano (CO-EO), demonstrated antioxidant profiles with a radical neutralizing potential (DPPH•) of IC50: 1.11 ± 0.019; 1.08 ± 0.05; 40.56 ± 0.227 and 0.69 ± 0.004 mg/mL, respectively. They also revealed a ferric ion reducing capacity (FRAP) of 93.05 ± 0.52; 97.72 ± 0.42; 21.85 ± 0.57 and 117.24 ± 0.64 mg Eq Trolox/g. A reduction in β-carotene degradation of 65.71 ± 0.04; 51.97 ± 0.66; 43.58 ± 1.56 and 57.46 ± 1.56 %. A total phenol content (Folin-Ciocalteu) of 132.97 ± 0.77; 141.89 ± 2.56; 152.04 ± 0.10 and 25.66 ± 0.40 mg EGA/g. Chemical characterization performed by gas chromatography mass spectrometry (GC-MS) showed that the respective major components of the samples were thymol (T-EO: 45.78 %), thymol (CT-EO: 43.57 %), alloaromadendrene (O-EO: 25.17 %) and carvacrol (CO-EO: 62.06 %). Regarding antifungal activity, it was evident that at the in vitro level, both commercial EOs had a MIC of 250 ppm while the extracted thyme EO had a MIC of 500 ppm; In vivo studies demonstrated that the application of thyme EO had a behavior similar to the synthetic fungicide, slowing down rot in bananas under storage conditions. Finally, partial least squares discriminant analysis (PLS-DA) and heat maps suggest p-cymene, carvacrol, linalool, eucalyptol, 4-terpineol, (z)-β-terpineol, alkanhol, caryophyllene, β-myrcene, d-limonene, α-terpinene, α-terpineol, d-α-pinene, camphene, caryophyllene oxide, δ-cadinene, terpinolene and thymol as relevant biomarkers associated with the assessed bioactive properties demonstrating the potential of extracted essential oils for the development of a botanical biofungicide.

Spray-drying and rehydration on β-carotene encapsulated Pickering emulsion with chitosan and seaweed polyphenol

The spray-drying process to generate microcapsules from Pickering emulsions needs high temperatures, leading to instability of emulsions and degradation of encapsulated thermosensitive compounds (β-carotene). However, these effects may be attenuated by the introduction of seaweed polyphenols into the emulsion interfacial layers, although the effects underlying this protective mechanism have not been explored. This study evaluates the effects of spray-drying/rehydration on the morphology, encapsulation efficiency, redispersibility, and stability of β-carotene loaded Pickering emulsions stabilized by chitosan (PESC) and Pickering emulsions stabilized by chitosan/seaweed polyphenols (PESCSP). The encapsulation efficiency of β-carotene in PESCSP microcapsules (61.13 %) was higher than PESC (53.91 %). Rehydrated PESCSP exhibited more regular droplet size distribution, higher stability, stronger 3D network morphology, and lower redispersibility index (1.5) compared to rehydrated PESC. Analyses of interfacial layers of emulsions revealed that chitosan covalently bound fatty acids at their hydrophobic side. Polyphenols were linked to chitosan at the hydrophilic side of emulsions through hydrogen bonds, providing 3D network between droplets and antioxidant activities to inhibit the degradation of β-carotene. This study emphasized the role of polyphenols in the interfacial layers of Pickering emulsions for the development of efficient delivery systems and protection of β-carotene and other thermosensitive bioactive compounds during spray-drying and rehydration.

Elevated temperature extraction of β-carotene from freeze-dried carrot powder into sunflower oil: Extraction kinetics and thermal stability.

β-Carotene, a precursor of vitamin A, can alleviate the deficiency of this vitamin prevalent worldwide. Earlier research studies have addressed the extraction of β-carotene at relatively low temperatures (up to 70°C) due to its perceived instability at higher temperatures, as a result of which extraction rates recorded are relatively low. This study models the net rate of β-carotene extraction by considering both extraction and degradation kinetics. The model developed, which accounts for degradation occurring in solid and extract phases, has been experimentally validated for the extraction of β-carotene from freeze-dried carrot powder into sunflower oil over a range of temperatures 90-150°C. This study also gives insights into the application of sunflower oil as a carrier for β-carotene during cooking and food processing, by monitoring and modeling the thermal degradation and isomerization of β-carotene at temperatures up to 220°C. The modeling of extraction kinetics shows that it is possible to achieve viable extraction rates by employing temperatures in the range (90-150°C) for relatively short times (<5min). The degradation kinetics shows that almost 75% of the β-carotene can survive heating at 180°C for 10min-indicating the possibility of using β-carotene enriched edible oils for frying. This study also reports on the formation of three isomers of β-carotene identified using HPLC: trans-, 9-cis, and 13-cis. The reaction network model developed in this study was able to account for the transient variation of the concentration of all three isomers. PRACTICAL APPLICATION: β-Carotene is a precursor of vitamin A and its consumption can potentially alleviate the deficiency of this vitamin prevalent worldwide. This study validates a model for the extraction of β-carotene in sunflower oil, which takes into account extraction as well as degradation occurring during extraction, so that a rational method is available for the design of efficient extractors for this purpose. This paper also establishes the thermal stability of β-carotene under frying conditions by quantifying its thermal degradation as well as isomerization.

Exploration of bigel 4D printing with spontaneous colour change for monitoring bio-actives kinetic behaviour based on the dual-units 3D printer

This work studied the effect of storage at different temperatures on the relationship between the colour change and bio-actives (curcumin and β-carotene) content change in the bigels 3D printing products. At relatively low temperatures (4 °C and 15 °C), β-carotene degraded rapidly, but a* changed slowly because of less migration of curcumin, indicating that colour change cannot be used for monitoring bio-active changes. At relatively high temperatures (25 °C and 35 °C), the β-carotene degradation fractions reached 0.924 and 0.967. Meanwhile, a* increased to 7.318 and 11.710 while the curcumin migration fraction increased quickly, which indicated that changes in colour and bio-actives content had high consistency at 25 °C and 35 °C. At these temperatures, the bigels 3D printing product lost structure stability due to the high freedom of moisture in hydrogel and increased mobility of oleogel, leading to rapid colour change and fast molecular movement of curcumin and β-carotene.

Chlorogenic acid-chitosan copolymers: Synthesis, characterization and application in O/W emulsions for enhanced β-carotene stability

In this study, chlorogenic acid-chitosan (CA-CS) copolymers were prepared with varying Chitosan (CS): chlorogenic acid (CA)ratios and characterized for their water solubility, antioxidant capacity, and emulsions stability. Results showed that CA-CS samples exhibited up to 90.5 % increase in DPPH scavenging efficiency and 20 % increase in hydroxyl radical scavenging efficiency compared to CS alone. CA-CS copolymers used to stabilize oil in water (O/W) emulsions, which were evaluated for their potential in encapsulating and protecting β-carotene. Microscopic observations revealed homogeneous spherical droplets in stable emulsions, suggesting effective interfacial structures. The selected CA-CS-stabilized O/W emulsions demonstrated encapsulation efficiencies of 74.8 % and 75.26 % for β-carotene. The CA-CS stabilized O/W emulsions provided the most effective protection against β-carotene degradation under UV exposure, retaining over 80 % of β-carotene content after 12 h of testing. These findings indicate that CA-CS-based O/W emulsions show promise as carriers and protectors for bioactive compounds, due to their improved antioxidant capacity, emulsions stability, and protection against degradation.

Effect of different composition and emulsifier types on the stability of red palm oil emulsified powder​

Red palm oil (RPO) has high nutritional content such carotene and vitamin E. However, those components in RPO are unstable and sensitive when exposed to light or temperature. Thus, the sensitive and unstable of nature components of red palm oil highlights the importance of encapsulation process via emulsification in early stage. The objective of this study was to investigate the stability of β-carotene in RPO encapsulated powder using α-cyclodextrin as wall material with the comparison of the emulsifier used between sodium caseinate (NaCAS) and lecithin in terms of production of RPO encapsulated powder. The protective effects provided by encapsulated powder process were evaluated in terms of the degradation kinetics of β-carotene at 60 ℃ for 25 days. Stability of β-carotene in RPO emulsified powder was fitted well using a first kinetic model. Degradation of β-carotene in encapsulated powder could be correlated using the first kinetic model. The stability of β-carotene with lecithin as emulsifier in both solid contents (25 wt.% and 35 wt.%) were more stable with degradation rate constant 0.018 day−1day−1 and 0.016 day−1day−1, respectively. Encapsulation process protected RPO during storage, with lecithin emulser performing better than NaCAS emulsifier.

Saffron Stigmas Apocarotenoid Contents from Saffron Latent Virus (SaLV)-Infected Plants with Different Origins and Dehydration Temperatures

Saffron is a spice that is obtained by dehydrating the stigmas of the Crocus sativus flower. Iran is the country that produces the largest amount of saffron, exceeding 90% of world production. Currently, there is a growing medicinal use which implies that there is more demand than supply worldwide, in turn, a large amount of labor is required to obtain it; for these two reasons, it reaches a high price in the international market. This demand is due to the high concentration of apocarotenoid metabolites that it biosynthesizes. In this work, the content of these metabolites of saffron from six production areas of Iran and neighbouring countries infected with saffron latent virus (SaLV) and dehydrated at two temperatures is compared. The corms of the six provenances were planted in a homogeneous plot and the stigmas analyzed were those of the second year after planting. The analysis showed that corms do not completely retain the memory of their original origin. In general, the ratio of the sum of mmol/kg of HTCC derivatives to the sum of the mmol of crocins is greater than two. This implies that the biosynthesis of saffron apocarotenoids due to the degradation of β-carotene towards HTCC is more important than that of zeaxanthin formation, which later gives HTCC and crocetin dialdehyde.

β-Carotene and Lycopene Degradation Kinetics of Tarhana Dough During Convective Air Drying and Traditional Drying Methods

In this study, tarhana doughs were dried with convective air drying at 30, 40 and 50 oC temperatures and 0.5, 1.25 and 2 m/s air velocities, and with traditional drying (sun-drying method). By this way effects of drying air temperature and velocity on degradation kinetics of β-carotene and lycopene during air drying of tarhana samples were investigated and the results compared with traditional drying method. The degradation reaction of β-carotene and lycopene was found to be following the first-order kinetic model. The reaction rate constant values of the β-carotene degradation were determined in the range of 0.0003-0.0025 min-1, and the activation energy values were determined in the range of 6.15-49.05 kJ/mol. The reaction rate constant values of the lycopene degradation were determined in the range of 0.0001-0.0007 min-1, and the activation energy values were determined in the range of 20.5-34.3 kJ/mol. β-carotene and lycopene content of tarhana samples decreased with the increase in drying temperature, and the rate of degradation reactions of these components increased with the increase in temperature and air velocity. As a result, it was determined that β-carotene and lycopene were better preserved at 1.25 m/s air velocity at 30 oC.

Characterization and utilization of soy protein isolate-(-)-epigallocatechin gallate-maltose ternary conjugate as an emulsifier for nanoemulsions: Enhanced physicochemical stability of the β-carotene nanoemulsion.

In this study, a ternary conjugate was prepared by covalent bonding of protein, polysaccharide, and polyphenol via ultrasound and the Maillard reaction. Subsequently, the β-carotene nanoemulsion was prepared with the soy protein isolate-(-)-epigallocatechin gallate-maltose (SPI-EGCG-maltose) conjugate as the emulsifiers via ultrasound. The SPI-EGCG-maltose conjugate showed superior solubility, emulsification and foaming properties at 4h reaction time. Meanwhile, the retention rates of β-carotene in the nanoemulsion after 30 d of storage, 8h of light, and 55°C of heat were >60%, >75%, and >60%, respectively. Furthermore, ultrasound treatment at 500W for 10min produced an inhibitory effect on the degradation of β-carotene. This study indicates that the nanoemulsion based on the ternary conjugate can effectively inhibit the β-carotene degradation by the external environment and prevent the oxidation and degradation of β-carotene in the nanoemulsion.

Characterization of Carotenoid Cleavage Oxygenase Genes in Cerasus humilis and Functional Analysis of ChCCD1.

Carotenoid cleavage oxygenases (CCOs) are key enzymes that function in degrading carotenoids into a variety of apocarotenoids and some other compounds. In this study, we performed genome-wide identification and characterization analysis of CCO genes in Cerasus humilis. Totally, nine CCO genes could be classified into six subfamilies, including carotenoid cleavage dioxygenase 1 (CCD1), CCD4, CCD7, CCD8, CCD-like and nine-cis-epoxycarotenoid dioxygenase (NCED), were identified. Results of gene expression analysis showed that ChCCOs exhibited diverse expression patterns in different organs and in fruits at different ripening stages. To investigate the roles of ChCCOs in carotenoids degradation, enzyme assays of the ChCCD1 and ChCCD4 were performed in Escerichia coli BL21(DE3) that can accumulate lycopene, β-carotene and zeaxanthin. The prokaryotic expressed ChCCD1 resulted in obvious degradation of lycopene, β-carotene and zeaxanthin, but ChCCD4 did not show similar functions. To further determine the cleaved volatile apocarotenoids of these two proteins, headspace gas chromatography/mass spectrometer analysis was performed. Results showed that ChCCD1 could cleave lycopene at 5, 6 and 5', 6' positions to produce 6-methy-5-hepten-2-one and could catalyze β-carotene at 9, 10 and 9', 10' positions to generate β-ionone. Our study will be helpful for clarifying the roles of CCO genes especially ChCCD1 in regulating carotenoid degradation and apocarotenoid production in C. humilis.

Thermal stabilities of lycopene and β-carotene in tomato pulp and pink grapefruit juice

Thermal stabilities of lycopene and β-carotene in tomato pulp and pink grapefruit juice were studied at 80, 95 and 110 °C. Lycopene and β-carotene degradations in both products followed to first-order reaction kinetics, but biphasic curves were obtained for β-carotene degradation. Stabilities of both pigments are highly affected by processing temperatures. For example, t 1/2 values for lycopene degradation decreased from 7.4 at 80 °C to 4.0 h at 110 °C in tomato pulp, and from 32.1 to 5.9 h in pink grapefruit juice, respectively. Similar decreases in t 1/2 values (46.8–27.3 h in tomato pulp and 113.6 to 11.7 h in grapefruit juice, respectively) were obtained for β-carotene degradations. Lycopene and β-carotene degradations in tomato pulp were not very sensitive to temperature elevations (E a = 22.7 and 20.2 kJ/mol, respectively), but very sensitive in pink grapefruit juice (E a = 63.8 and 85.3 kJ/mol, respectively). High correlations were found between a*, b*and h° values, and lycopene concentrations ( r = 0.659–0.978) and β-carotene concentrations ( r = 0.647–0.997). • Both pigments showed much higher thermostability in grapefruit juice than tomato pulp. • Both pigments were more sensitive to temperature changes in grapefruit juice than tomato pulp. • High correlations were found between colour values and pigment contents in both products. • Changes in red colour of both products can be followed by measuring a* and h° values. • Changes in yellow colour can be tracked by measuring h° values in tomato pulp.

Oxidative stability by isothermal calorimetry of solid lipid microparticles produced by particles from gas saturated solutions technique

This study aimed to investigate the application of isothermal calorimetry as technique for monitoring microparticles oxidation produced by particles from gas saturation solution (PGSS) technique. Microparticles were obtained by mixing linseed oil (9.1 g/100 g) with glycerol stearate (90.9 g/100 g). The process was carried out at 10 MPa, 55 °C for 30 min. To enhance microparticles oxidative stability, β-carotene was also added to the formulation (0.4 up to 1.6 mg/g of oil). The results showed that the fatty acid profile of the oil did not change after the encapsulation process. From the isothermal calorimetry traces, it was possible to determine the induction time (τIC) and the rates of oxidation during the inhibited (Rinh) and uninhibited (Runi) period. The microencapsulation by PGSS significantly (p < 0.05) increased τIC values of microparticles compared to the bulk oil, which resulted equal to 32 ± 1 × 104 s and 10.2 ± 2 × 104 s, respectively. On the other side, Rinh significantly decreased confirming the higher microparticles oxidative stability. β-carotene addition enhanced the oxidative stability proportionally to the concentration of the added antioxidant. At the end of the oxidation, the 3-OH-beta-apo-11-carotenal and the 3-OH-beta-apo-carotenone compounds derived from β-carotene degradation were detected.

Combined Heat and Mass Transfer Associated with Kinetics Models for Analyzing Convective Stepwise Drying of Carrot Cubes.

Stepwise drying is an effective technique that promotes energy saving without additional capital cost. The stepwise drying mode was investigated for energy consumption and dried product qualities using a coupled heat and mass transfer model associated with kinetics equations of volume shrinkage and degradation of β-carotene in carrot cubes. Simulations were performed using a finite element method with extension of a chemical species transport. Validation experiments were carried out under constant drying modes at 60 °C, 70 °C and 80 °C using a lab-scale convective hot air dryer. The verified models were subsequently employed to investigate the effects of two step-up drying modes (60 to 70 °C and 60 to -80 °C). The optimal drying condition was determined using the synthetic evaluation index (SI) with criteria of high specific moisture evaporation rate (SMER), low shrinkage ratio and β-carotene degradation. Simulated results showed comparable agreement with experimental data of moisture content, shrinkage ratio and β-carotene ratio. Step-up drying of 60 to 70 °C gave the highest SMER of 0.50 × 10-3 kg of water evaporated per kWh, while the operation at constant temperature of 80 °C gave the lowest value of 0.19 × 10-3 kg of water evaporated per kWh. Model-predicted results showed less shrinkage of carrot cubes, but higher degradation of β-carotene under step-up drying compared to single-stage drying under temperature of 60 °C. Based on the highest SI value (0.36), carrot cubes were optimally dried under step-up mode of 60 to 70 °C.

Encapsulation of β-carotene into food-grade nanofibers via coaxial electrospinning of hydrocolloids: Enhancement of oxidative stability and photoprotection

Εncapsulation of β-carotene in two different food hydrocolloid matrices, pure pullulan (PUL) and its blend with whey protein isolate (WPI) at a weight ratio of WPI:PUL 30:70, via coaxial electrospinning, was investigated. Τhe encapsulation efficiency of β-carotene in the generated WPI:PUL (30:70 w/w) and PUL nanofibers has reached up to ∼90% and ∼95%, respectively. Among the various operating parameters examined, the factor which had the greatest impact on encapsulation efficiency was the oil-β-carotene solution (core material) flow rate. More uniform thread-like nanofibers were obtained using pure pullulan as wall material, while the WPI:PUL (30:70 w/w) blend resulted in formation of nanostructures with bead-shaped morphologies periodically along the fiber axis. The β-carotene degradation kinetics followed an apparent first-order reaction model, showing highest values of the rate constants at an intermediate water activity level (aw = 0.53) for all matrices and storage temperatures (25 °C, 35 °C, 45 °C) examined. The degradation kinetics did not seem to be directly related with the molecular mobility of the fiber polymeric components (i.e., physical state of the amorphous wall material), as β-carotene losses were evident even at temperatures below their glass transition temperatures ( T g ). The electrospun WPI:PUL nanofibers were more suitable as carriers in delaying oxidation of β-carotene under different storage temperatures, a w levels and exposure to UV–Vis irradiation, compared to pure PUL. Overall, the coaxial electrospinning process using the mixture of WPI:PUL (30:70 w/w) as an encapsulation vehicle appears to be an effective technique to fabricate functional foods or dietary supplements enriched with β-carotene. • β-carotene was encapsulated through coaxial electrospinning for food applications. • β-carotene can be effectively encapsulated in WPI:PUL (30:70) and PUL nanofibers. • β-carotene solution flow rate had the greatest impact on encapsulation efficiency. • Both encapsulation structures showed improved stability at low humidity environments. • Electrospun WPI:PUL (30:70) nanofibers were more effective than PUL ones.

Thermal-induced impact on physicochemical property and bioaccessibility of β-carotene in aqueous suspensions fabricated by wet-milling approach

The physicochemical properties of β-carotene in aqueous system were scarcely explored before. Herein, β-carotene aqueous suspensions were fabricated by wet-milling, and the impact of milling temperature on thermal degradation kinetics, coloring mechanism, recrystallization behavior and bioaccessibility of β-carotene in aqueous system was investigated. The thermodynamic parameters indicated that the degradation of total β-carotene and all-trans isomer in aqueous suspensions was endothermic and energetically unfavorable. The hue of aqueous suspensions was dependent on the particle size and cis isomer ratio of β-carotene (especially in the formation of 13-cis isomer). The reduced conjugation effect of CC groups was responsible to the hypochromicity and amorphization of isomerized β-carotene. The recrystallization rate of β-carotene in aqueous suspensions was decreased owing to the presence of higher magnitude of steric hindrance between the isomerized β-carotene. The bioaccessibility of β-carotene was significantly increased through the nanoencapsulation and elevating the level of cis isomers of β-carotene.

Antioxidant Activity, Metal Chelating Ability and DNA Protective Effect of the Hydroethanolic Extracts of Crocus sativus Stigmas, Tepals and Leaves.

The present study investigated the antioxidant activity, metal chelating ability and genoprotective effect of the hydroethanolic extracts of Crocus sativus stigmas (STG), tepals (TPL) and leaves (LV). We evaluated the antioxidant and metal (Fe2+ and Cu2+) chelating activities of the stigmas, tepals and leaves of C. sativus. Similarly, we examined the genotoxic and DNA protective effect of these parts on rat leukocytes by comet assay. The results showed that TPL contains the best polyphenol content (64.66 µg GA eq/mg extract). The highest radical scavenging activity is shown by the TPL (DPPH radical scavenging activity: IC50 = 80.73 µg/mL). The same extracts gave a better ferric reducing power at a dose of 50 µg/mL, and better protective activity against β-carotene degradation (39.31% of oxidized β-carotene at a 100 µg/mL dose). In addition, they showed a good chelating ability of Fe2+ (48.7% at a 500 µg/mL dose) and Cu2+ (85.02% at a dose of 500 µg/mL). Thus, the antioxidant activity and metal chelating ability in the C. sativus plant is important, and it varies according to the part and dose used. In addition, pretreatment with STG, TPL and LV significantly (p < 0.001) protected rat leukocytes against the elevation of percent DNA in the tail, tail length and tail moment in streptozotocin- and alloxan-induced DNA damage. These results suggest that C. sativus by-products contain natural antioxidant, metal chelating and DNA protective compounds, which are capable of reducing the risk of cancer and other diseases associated with daily exposure to genotoxic xenobiotics.

Theoretical study on the mechanism and kinetics of the formation β-carotene epoxides from the oxidative degradation of β-carotene

Some factors such as oxidation can significantly affect the level of β-carotene after processing and during the storage of foods. Oxidative degradation of β-carotene with the active forms of oxygen produces β-carotene 5,6 and 5,8-epoxides. Two mechanisms involving a direct attack on the double bonds of the β-carotene by 1O2 (a neutral mechanism) and 3O2 (a radical mechanism) oxygen have been proposed and considered kinetically and thermodynamically by the density functional theory method. It concluded that due to the smaller energy barrier in the first step, the neutral mechanism with 1O2 is a more desirable path than the diradical mechanism with 3O2 and this was in complete agreement with the experimental reality of more reactivity of 1O2. The energy barriers of the stepwise manner in the intersystem crossing pathway showed a more favorable pathway in the neutral mechanism. The deviation of spin contamination values was ignorable in the diradical mechanism.