Bioaccessibility Of Carotenes Research Articles

Development of highly stable phytosterol oleogel particle-based emulsions with improved bioaccessibility of ꞵ-carotene

Oral administration is the most preferred route for drug and bioactive delivery, although it raises great challenges due to the involvement of the gastrointestinal (GI) system and limited bioavailability. In this research, gelled oil particle-based emulsion with long shelf life and high gastrointestinal stability was successfully formulated using ꞵ-sitosterol and γ-oryzanol (SO) mixtures, as structuring agents, and tween 80 (TN80) as a surfactant. The effect of TN80 concentration, emulsification speed, γ-oryzanol and ꞵ-sitosterol ratio, and SO concentration was examined. The results show that the particle size was significantly reduced with homogenization speed, surfactant concentration, and SO concentration. The effect of SO concentration was further analyzed under simulated GI conditions and changes in their particle size, zeta potential, morphology, and ꞵ-carotene release were assessed. GI digestion tests revealed that unstructured oil particle-based emulsions exhibit a higher probability for particle coalescence compared to oleogel particle-based emulsions. The extent of lipid digestion was correlated to the particle size, with higher digestion extent at smaller particle size, and to the oleogel-network mechanical strength, with lower digestion extent in denser particle network. During the lipolysis process, smaller mixed micelles were formed when the particles were prepared using higher SO concentrations. Interestingly, an appreciable increase in the ꞵ-carotene bioaccessibility was observed, reaching maximum value at 10 %wt. SO, implying the effect of oil structuring on the ꞵ-carotene release process. Overall, these results suggest that the combination of solid texture and liquid lipid core in the oleogel particles offers mechanical protection and molecular micellization ability during digestion. Such characteristics can be utilized for effective encapsulation systems able to improve the bioaccessibility of hydrophobic molecules.

Red palm oil Pickering emulsion with pectin yields improved in vitro beta carotene bioaccessibility and oil stability: Physicochemical characterization and shelf stability studies

Pickering emulsion of red palm oil (RPO) with pectin as stabilizer was optimized using response surface methodology (RSM). RSM parameters for final red palm oil pickering emulsion (RPE) were 3% pectin, 30% RPO, and homogenization speed of 24,000 rpm for 15 min. RPE was subjected to physicochemical characterizations, along with storage studies for 15 days. Microstructure imaging of RPE confirmed pickering emulsion formation. Droplet diameter and zeta potential of RPE were 1.779 μm and −32.5 mV, respectively. Fourier transform infrared spectroscopy of RPE suggested hydrogen bonding interactions between the components, and thermogravimetric analysis revealed stability up to 40°C. Gastrointestinal bioaccessibility of naturally occurring β-carotene in the RPE (37.76 ± 1.2%) was found to be four times higher than that of RPO (8.7 ± 0.8%). The RPE was more stable at 4°C as indicated by storage analyses. RPE can improve the bioaccessibility of nutritionally important bioactive compounds. Practical applications Pickering emulsions of RPO stabilized by pectin can be used for developing functional foods with improved bioaccessibility of lipophilic bioactives such as carotenoids as well as for the delivery of temperature sensitive nutritional and bioactive compounds. These emulsions can also be found applications in beverages, low temperature processed foods and vegan fat substitutes.

Bioaccessibility of microalgae-based carotenoids and their association with the lipid matrix

The composition of microalgae can contribute to nutritious and functional diets. Among the functional compounds, carotenoids are in focus since positive effects on human health have been established, which are in turn related to their bioaccessibility. In addition to essential nutrients, our hypothesis was that microalgae biomasses could be used as sources of bioaccessible carotenoids. Thus, this study determined for the first time the bioaccessibility of carotenoids from biomass of Scenedesmus bijuga and Chlorella sorokiniana and their possible relationship with the lipid composition of the matrix. The samples were submitted to in vitro digestion protocol, and carotenoids were determined by HPLC-PDA-MS/MS. Individual bioaccessibility of carotenoids was ≥ 3.25%. In general, compounds in their cis conformation were more bioaccessible than trans; and total carotenes more than total xanthophylls. Twelve compounds were bioaccessible from the biomass of S. bijuga, and eight in C. sorokiniana. In S. bijuga, the bioaccessibility of total carotenoids was 7.30%, and the major bioaccessible carotenoids were 9-cis-β-carotene (43.78%), 9-cis-zeaxanthin (42.30%) followed by 9-cis-lutein (26.73%); while in C. sorokiniana, the total bioaccessibility was 8.03%, and 9-cis-β-carotene (26.18%), all-trans-β-carotene (13.56%), followed by 13-cis-lutein (10.71%) were the major compounds. Overall, the total content of lipids does not influence the bioaccessibility of total carotenoids. Still, the lipid composition, including structural characteristics such as degree of saturation and chain length of the fatty acid, impacts the promotion of individual bioaccessibility of carotenes and xanthophylls of microalgae. Finally, the results of this study can assist the development of microalgae-based functional food ingredients and products.

Effects of cooking and extra virgin olive oil addition on bioaccessibility of carotenes in tomato sauce

In this study, the effects of cooking and the addition of extra virgin olive oil on the in vitro bioaccessibility of carotenoids in tomato sauce were evaluated. The results indicated that total antioxidant activity, α-tocopherol, lycopene, β-carotene, lutein, and chlorophyll a contents were positively affected by the combination of cooking and addition of extra virgin olive oil. Moreover, after in vitro digestion, for intestinal phase, lycopene and Β-carotene were observed in all samples, whereas α-tocopherol and chlorophyll a were not detected in any of the samples. Lycopene (≈8.5-fold) and β -carotene (≈5-fold) were significantly improved (P < 0.05) by the effect of cooking and addition of extra virgin olive oil to the samples compared to control tomato sauce (without oil and cooking).

Effect of processing and oil type on carotene bioaccessibility in traditional foods prepared with flour and puree from orange‐fleshed sweetpotatoes

SummaryConsumption of Orange‐Fleshed sweetpotato (OFSP) and products as source of provitamin A is being promoted to tackle vitamin A deficiency (VAD) in sub‐Saharan Africa. However, limited information is available on β‐carotene retention in foods and delivery after digestion. The study assessed carotene retention and bioaccessibility following in vitro digestion on traditional foods having OFSP among the ingredients. Sunflower oil, margarine and beef fat were evaluated on their effect on β‐carotene bioaccessibility. Porridge and chapatis were prepared with either OFSP puree or flours in the formulations. Carotene retention was highest in chapatis (83%) as compared to porridge (65%). Micerallisation efficiency of all‐trans β‐carotene was comparable between similar products but greater in chapatis (62%) than porridge (11%). Sunflower oil had the highest all‐trans β‐carotene bioaccessibility compared to margarine and beef fat. The results support the promotion of consumption of OFSP‐based products as good source of provitamin A to fight VAD.

Carotenoid and polyphenol bioaccessibility and cellular uptake from plum and cabbage varieties

Plum and cabbage are rich in carotenoids and polyphenols. However, their bioactivity depends on their release and intestinal uptake. Four varieties of Brassicaceae (Duchy, Scots Kale, Kale, Kalorama) and Prunus (Cherry Plum, Plum 620, Ersinger, Italian Plum) were studied; bioaccessibility following in vitro digestion, cellular uptake (Caco-2 vs. co-culture cell model: Caco-2:HT-29-MTX (90:10%) and colonic fermentation were determined for carotenoids/polyphenols; the influence of certain kitchen preparations was likewise studied. Carotenoids were non-significantly influenced by the latter, while for polyphenols, boiling and steaming significantly reduced total phenolics (p<0.05). Carotenoid bioaccessibility did not differ significantly between Prunus vs. Brassicaceae varieties, but xanthophyll was higher than carotene bioaccessibility (p<0.01). Polyphenol bioaccessibility was low (<10%), possibly compromised by the cream containing test meal. Total carotenoid cellular uptake varied between varieties (0.3–4.1%), being higher for carotenes (4.1%) than for xanthophylls (1.6%, p<0.01), and were higher for the co-culture cell model compared to Caco-2 cells (p<0.01). Total carotenoid recovery in the colonic fraction varied from 4% to 25%. Lower bioaccessibility of carotenes thus appeared to be somewhat counterbalanced by higher cellular uptake. The potential positive role of the mucus layer for cellular uptake and the fate of the colonic digesta deserve further attention in the future.

ADAPTION OF AN IN VITRO DIGESTION METHOD TO EVALUATE CAROTENOID ACCESSIBILITY FROM VEGETABLES

There is evidence that carotenoids, the fat-soluble pigments in fruits and vegetables, are linked to improvements in certain chronic diseases including agerelated macular degeneration, cell-transformation and cardiovascular diseases. It is also known that for humans the bioavailability of carotenoids present in fruits and vegetables is comparatively low and strongly dependent on carotenoid species, chemical structure and food matrix. In this study, an in vitro digestion approach was used to screen the bioaccessible carotenoid content of raw and processed vegetables after three main digestion steps with saliva, gastric- and duodenal juices. The experimental setup was based on the in vitro digestion model of Oomen et al. (2003). First raw or cooked vegetable samples were chopped and incubated at 37°C for 10 min in a shaking water bath with human saliva (pH 6.5; α-amylase). Afterwards, simulation of the gastric phase was achieved by addition of gastric juice (pH 1.0; porcine pepsin) and incubated for an additional 1 h. In a third step, duodenal juice (pH 7.8; porcine pancreatin, porcine lipase) and porcine bile solution (pH 8.0) were added. Samples were then incubated under nitrogen for 2 h, centrifuged and the supernatants were freeze-dried. The six most important nutritional carotenoids (lutein, zeaxanthin, β-crypthoxanthin, α-carotene, β-carotene, lycopene) were quantified by HPLC-UV/VIS. The carotenoids were separated in 47 min on a C30 column with a methanol/MTBE gradient and detected by diode array detection (DAD). Freeze-dried supernatants were redissolved in the eluent, centrifuged and filtered before injection. External standards were used for quantification. In raw green leafy vegetables the carotenoid accessibility was low compared to orange/red colored vegetables and ranged between 4-16% for lutein, 7-25% for zeaxanthin and 12-22% for β-carotene. The bioaccessibility of carotenes and xanthophylls from raw red and orange vegetables was considerably higher and up to 57%. Generally, an increased carotenoid accessibility was observed after thermal processing. This adapted in vitro digestion method is a promising tool to investigate the carotenoid bioaccessibility from vegetables.

In vitro bioaccessibility of health-related compounds as affected by the formulation of fruit juice- and milk-based beverages

The purpose of this research was to evaluate the influence of the beverage formulation on the in vitro digestibility and bioaccessibility of phenolic compounds, vitamin C, and carotenoids, as well as antioxidant activity from milk, a blended fruit juice (BFJ) and a combination of both of them (BFJ–MB). The release of many phenolic substances was improved during gastric digestion of milk and BFJ–MB (around 5 and 75%), but not in BFJ. Vitamin C and carotenoids diminished significantly (P<0.05) in the gastric and intestinal digesta of each beverage. Phenolic acids, flavonoids, vitamin C and hydrophilic constituents with antioxidant activity were more bioaccessible in BFJ (up to 3.4 times) than in milk and BFJ–MB. On the contrary, the bioaccessibility of carotenes, xanthophylls and those compounds with lipophilic antioxidant activity was improved when milk was added to BFJ (up to 1.9 times). Results suggest that the addition of milk improved the bioaccessibility of lipophilic constituents but not that of hydrophilics. Nevertheless, BFJ–MB combines the nutritional ingredients of milk and BFJ. As a result, BFJ–MB could supply a higher diversity of bioaccessible compounds in comparison to that of milk and BFJ alone, promoting health and protecting against several diseases.

High Pressure Homogenization Increases the In Vitro Bioaccessibility of α‐ and β‐Carotene in Carrot Emulsions But Not of Lycopene in Tomato Emulsions

The correlation between food microstructure and in vitro bioaccessibility of carotenes was evaluated for tomato and carrot emulsions (5% olive oil) subjected to high pressure homogenization (HPH) at varying degrees of intensity. The aim was to investigate whether additional mechanical disruption of the food matrix could be utilized to further increase the carotene bioaccessibility of an already pre-processed material. The carotene bioaccessibility of the samples was measured after simulated in vitro digestion, carotene release to the oil phase was estimated by Confocal Raman spectroscopy and, to measure active uptake of carotenes, Caco-2 cells were incubated with the digesta of selected samples. HPH did not notably affect the retention of carotenes or ascorbic acid but significantly increased both the release and micellar incorporation of α- and β-carotene in carrot emulsions 1.5- to 1.6-fold. On the other hand, in vitro bioaccessibility of lycopene from tomato was not increased by HPH under any of the conditions investigated. Instead, the results suggested that lycopene bioaccessibility was limited by a combination of the low solubility of lycopene in dietary lipids and entrapment in the cellular network. Carotene uptake by Caco-2 cells appeared to be mainly dependent upon the carotene concentration of the digesta, but cis-trans isomerization had a significant impact on the micellarization efficiency of carotenes. We therefore conclude that HPH is an interesting option for increasing the bioaccessibility of carotenes from fruits and vegetables while maintaining a high nutrient content, but that the results will depend on both food source and type of carotene. A better understanding of the correlation between the processing of fruits and vegetables, microstructure and nutrient bioaccessibility can be directly applied in the production of food products with an increased nutritional value.

Changes in microstructure, beta carotene content and in vitro bioaccessibility of orange-fleshed sweet potato roots stored under different conditions

Orange-fleshed sweet potatoes {OFSP} (Ipomoea batatas (L.) Lam) contain high levels of beta carotene, an important provitamin A carotenoid. Stored sweet potato roots undergo many physiological changes that affect their beta carotene content and bioaccessibility as well as the tissue microstructure. This study investigated the changes in microstructure, beta carotene content and in vitro bioaccessibility of stored OFSP roots. Roots of two varieties of OFSP, Ejumula and SPK004/6/6 were each stored under the following conditions: in a pit (17-21 oC, RH 90-100%), saw dust (19-23oC, RH 86- 100%), dark room (24.5-28 oC, RH 68-100%) and ambient (24-27 oC, RH 68-100%). Samples were drawn monthly from each of the storage treatments and analyzed for changes in beta carotene content, in vitro bioaccessibility and tissue microstructure. Stored roots of Ejumula variety contained significantly more (P 0.05) beta carotene than those of the SPK004/6/6 variety. There was no significant difference (P 0.05) between varieties in regards to beta carotene bioaccessibility. Roots stored in pits retained higher beta carotene content compared to roots stored under other conditions. In vitro bioaccessibility was significantly higher (P 0.05) in roots stored in pits compared to roots stored under saw dust, dark room and ambient conditions. Samples of OFSP roots stored under ambient and dark room conditions retained the least amount of beta carotene and had the least amount of bioaccessible beta carotene. There was an increase in the level of cell wall lignification during storage of OFSP. The extent of lignification varied with storage method used. The roots stored under ambient and dark room conditions showed higher levels of lignification compared to those stored under sawdust and in pits. There were no differences in lignification between the different varieties studied. The study shows that storage of OFSP roots using methods that maintain low temperatures leads to higher retention of beta carotene and maintains higher in vitro bioaccessibility.Key words: Storage, beta carotene, bioaccessibility, microstructure

Effect of Carrot (Daucus carota) Microstructure on Carotene Bioaccessibility in the Upper Gastrointestinal Tract. 2. In Vivo Digestions

Nutrient bioaccessibility and subsequent absorption will be directly influenced by changes in food structure during gastrointestinal processing. The accompanying paper (Tydeman et al. J. Agric. Food Chem. 2010, 58, doi: 10.1021/jf101034a) reported results on the effect of carrot processing on the release of carotene into lipid phases during in vitro gastric and small intestinal digestions. This paper describes results from in vivo digestion of two of the types of processed carrot used previously, raw grated carrot and cooked carrot mashed to a puree. Ileostomy effluents from human volunteers fed meals containing the carrot material were used to study tissue microstructure and carotene release. Raw carrot shreds and intact cells that had survived the pureeing process were identifiable in ileal effluent. The gross tissue structure in the shreds had not changed following digestion. Carotene-containing particles remained encapsulated in intact cells, but were absent from ruptured cells. Microscopy revealed marked changes to the cell walls including swelling and pectin solubilization, which increased in severity with increasing residence time in the upper gut. These observations were entirely consistent with the in vitro observations. It was concluded that a single intact cell wall is sufficient to reduce carotene bioaccessibility from a cell by acting as a physical barrier, which is not broken down during upper gut digestion.

Effect of Carrot (Daucus carota) Microstructure on Carotene Bioaccessibilty in the Upper Gastrointestinal Tract. 1. In Vitro Simulations of Carrot Digestion

Studies investigating carotene bioaccessibility (release from the food matrix to a solubilized form) directly from plant material during the process of digestion are scarce, mainly due to the difficulties associated with obtaining such material. Therefore, this paper examines the relationship between tissue microstructure and carotene bioaccessibility using an in vitro digestion model. Dietary oil provides a pool for the initial solubilization. Therefore, carotene partitioning into an emulsified oil phase was assessed using raw carrot tissue and carrot tissue subjected to various degrees of heating and particle size reduction and, in all cases, was found to be greatly reduced compared with juiced carrot. Carotene bioaccessibility was found to be greater from raw tissues than heated tissues of the same size. This is because heating increases the propensity for intact cells to separate, effectively encapsulating the carotene. Although the gross structure of the tissues was found to be relatively unaffected by in vitro digestion, at the cellular level some cell-wall swelling and cell death were observed, particularly close to the surfaces of the tissue. This study suggests that cell-wall rupture prior to digestion is an absolute requirement for carotene bioaccessibility in the upper intestine and that heating does not enhance carotene release from intact cells.

Microstructure and In Vitro Beta Carotene Bioaccessibility of Heat Processed Orange Fleshed Sweet Potato

Orange fleshed sweet potato (OFSP) has been identified as a good source of beta-carotene but the beta-carotene bioaccessibility is affected by processing. In this study, the effect of traditional heat processing methods on the microstructure and in vitro bioaccessibility of beta-carotene from OFSP were investigated. Bioaccessibility was determined using simulated in vitro digestion model followed by membrane filtration to separate the micellar fraction containing bioaccessible beta-carotene. Processing led to decrease in the amount of all-trans-beta-carotene and increase in 13-cis-beta-carotene. Processed OFSP had significantly higher (P < 0.05) bioaccessible beta-carotene compared to the raw forms. Bioaccessibility varied with processing treatments in the order; raw < baked < steamed/boiled < deep fried. Light microscopy showed that the microstructure of OFSP was disrupted by the processing methods employed. The cell walls of OFSP were sloughed by the traditional heat processing methods applied. The findings show that heat processing improves bioaccessibility of beta-carotene in OFSP and this was probably due to disruption of the tissue microstructure.

Bioaccessibility of carotenes from carrots: Effect of cooking and addition of oil

Food processing and occurrence of dietary lipids are believed to be important and limiting factors for carotenoid bioavailability in humans. In the present study the isolated and combined effects of household cooking and addition of olive oil on the bioaccessibility of carotenes from carrots have been investigated. Although thermal treatment during cooking showed to have a negative impact on the carotenoid content, a positive effect on the micellarisation of carotenes and therefore on their bioaccessibility was found. Carotenes transferred to the digests were micellarised to a higher extent from cooked carrots (52%) than from crude carrots (29%). Addition of olive oil to carrot samples during cooking and before application of the in vitro digestion model had a marked positive effect on the release of carotenes, although the design of the model did not allow the correct estimation of this effect. The higher amounts of micellarised carotenes (80%) were found in the digest prepared from cooked carrots containing 10% olive oil. In general, the inclusion of olive oil during cooking increased the carotenoid extraction and micellarisation in a dose-dependent fashion. Although β-carotene and α-carotene were affected in a similar way by the cooking process, α-carotene appeared to be more efficiently incorporated into the micelles when olive oil was added to the samples. In conclusion, both processing and mainly lipid content (cooking oil in this case) significantly improve carotenoid bioaccessibility from carrots, and therefore may increase bioavailability in humans. The consumption of carotenoid-rich foods such as fruits and vegetables has been associated with a decrease of the risk of developing certain types of degenerative and chronic diseases. Processing of food and the interaction of carotenoids with lipophilic food components or ingredients may modify the amount of the released pigment from the food matrix, and therefore potentially increase or decrease their bioavailability. For this purpose, in the present study we have investigated the effects of cooking and presence of olive oil on the release of carotenes from carrots (as a model food) and their incorporation into absorbable micelles, the bioaccessibility. From the industrial point of view, a better understanding of the factors governing the release of carotenoids and other active components from vegetable foods is of great importance with the aim of optimising the manufacturing processes.

Effect of Cell Wall Degrading Enzymes on In Vitro Carotene Accessibility in Lactic Acid Fermented Carrot Beverage

ABSTRACT: Carrot purées with different particle size were prepared from fresh carrots using 2 different food processors. The purées were fermented with lactic acid bacteria (Lactobacillus plantarum) with and without addition of cell wall degrading enzymes (Pectinex® Ultra SP‐L and CellubrixTM L). The bioaccessibility of carotenes was estimated using an in vitro digestion method. In carrots processed to a particle size &lt;1.5 mm, the in vitro β‐carotene accessibility was 46% and neither fermentation nor addition of cell wall‐degrading enzymes had any further effect on the in vitro accessibility. In carrot purées with a coarser particle size, the in vitro β‐carotene accessibility was 18%; that significantly increased by adding high amounts of cellulases or pectinases or a combination of the enzymes either in low or high amounts. The improved accessibility was correlated with reduced particle size of the carrot purée.