Recent advances in the bioaccessibility and bioavailability of carotenoids and effects of other dietary lipophiles

Impact of Protein-Enriched Plant Food Items on the Bioaccessibility and Cellular Uptake of Carotenoids

Carotenoids are lipophilic pigments which have been associated with a number of health benefits, partly related to antioxidant effects. However, due to their poor solubility during digestion, carotenoid bioavailability is low and variable. In this study, we investigated the effect of frequently consumed proteins on carotenoid bioaccessibility and cellular uptake. Whey protein isolate (WPI), soy protein isolate (SPI), sodium caseinate (SC), gelatin (GEL), turkey and cod, equivalent to 0/10/25/50% of the recommended dietary allowance (RDA, approx. 60g/d), were co-digested gastro-intestinally with carotenoid-rich food matrices (tomato and carrot juice, spinach), and digesta further studied in Caco-2 cell models. Lipid digestion, surface tension and microscopic visualization were also carried out. Co-digested proteins positively influenced the micellization of carotenes (up to 3-fold, depending on type and concentration), especially in the presence of SPI (p < 0.001). An increased cellular uptake was observed for xanthophylls/carotenes (up to 12/33%, p < 0.001), which was stronger for matrices with an initially poor carotenoid micellization (i.e., tomato juice, p < 0.001), similar to what was encountered for bioaccessibility. Turkey and cod had a weaker impact. Significant interactions between carotenoids, lipids and proteins were observed during digestion. Co-digested proteins generally improved lipid digestion in all matrices (p < 0.001), especially for carrot juice, though slight decreases were observed for GEL. Protein impact on the surface tension was limited. In conclusion, proteins generally improved both carotenoid bioaccessibility and cellular uptake, depending on the matrices and carotenoid-type (i.e., carotene vs. xanthophylls), which may be relevant under specific circumstances, such as intake of carotenoid-rich food items low in lipids.

Carotenoids in Milk and the Potential for Dairy Based Functional Foods

Carotenoids are a family of over 1100 known natural pigments synthesized by plants, algae, fungi and bacteria. Dietary intake of carotenoids is necessary for mammals as they cannot be synthesized in the body. In cows, the nature of the diet consumed strongly influences the composition of milk produced and this includes carotenoid concentration and profile. Fresh forage is the richest source of carotenoids for cows. The main carotenoids identified in forages are lutein, β-carotene, zeaxanthin and epilutein. Manipulating cow feed via carotenoid supplementation increases the carotenoid content of bovine milk. In humans, carotenoids have anti-oxidant, anti-inflammatory and provitamin A activity. Lutein is a major carotenoid in human milk and the brain tissue of adults and infants. Lutein and zeaxanthin are linked to improved eye health and cognitive function. Traditionally for humans, fruit and vegetables have been the main source of carotenoid intake. Functional foods present an opportunity to incorporate these naturally occurring compounds into milk products for added health benefits, widening the range of dietary sources of carotenoids. We offer an overview of the literature to date on carotenoid-fortified dairy products and infant formula. This review will describe and summarize the key mechanisms by which the carotenoid profile of bovine milk can be manipulated. We present findings on the origin and role of carotenoids in bovine and human milk, outline factors that impact the carotenoid content of milk, evaluate carotenoid-fortified milk products and discuss the associated challenges, such as bioaccessibility and stability.

The Potential of Sweetpotato as a Functional Food in Sub-Saharan Africa and Its Implications for Health: A Review

Increasing urbanization in developing countries has resulted in busier lifestyles, accompanied by consumption of fast foods. The consequence is an increased prevalence in noncommunicable diseases (NCDs). Food-based approaches would be cheaper and more sustainable in reducing these NCDs compared to drugs, which may have side effects. Studies have suggested that consuming functional foods could potentially lower NCD risks. Sweetpotato is regarded as a functional food because it contains bioactive compounds. Recently, sweetpotato has gained attention in sub-Saharan Africa (SSA), but research has focused on its use in alleviating micronutrient deficiencies such as vitamin A deficiency, particularly the orange-fleshed variety of sweetpotato. Some studies conducted in other parts of the world have investigated sweetpotato as a functional food. There is a need to characterize the sweetpotato varieties in SSA and determine how processing affects their bioactive components. This review highlights some of the studies conducted in various parts of the world on the functionality of sweetpotato, its bioactive compounds, and how these are influenced by processing. In addition, the potential health benefits imparted by sweetpotato are expounded. The knowledge gaps that remain in these studies are also addressed, focusing on how they can direct sweetpotato research in SSA.

Electrospraying as a novel process for the synthesis of particles/nanoparticles loaded with poorly water-soluble bioactive molecules

Hydrophobicity and low aqueous-solubility of different drugs/nutraceuticals remain a persistent challenge for their development and clinical/food applications. A range of nanotechnology strategies have been implemented to address this issue, and amongst which a particular emphasis has been made on those that afford an improved biological performance and tunable release kinetic of bioactives through a one-step process. More recently, the technique of electrospraying (or electrohydrodynamic atomization) has attained notable impulse in virtue of its potential to tune attributes of nano/micro-structured particles (e.g., porosity, particle size, etc.), rendering a near zero-order release kinetics, diminished burst release manner, as well as its simplicity, reproducibility, and applicability to a broad spectrum of hydrophobic and poorly water-soluble bioactives. Controlled morphology or monodispersity of designed particles could be properly obtained via electrospraying, with a high encapsulation efficiency and without unfavorable denaturation of thermosensitive bioactives upon encapsulation. This paper overviews the recent technological advances in electrospraying for the encapsulation of low queues-soluble bioactive agents. State-of-the-art, advantages, applications, and challenges for its implementation in pharmaceutical/food researches are also discussed.

Carotenoid absorption in rats fed with vacuum-fried papaya chips depends on processed food microstructure associated with saturated and unsaturated oils

Many studies indicate that food matrix microstructure and type of dietary oil or fat play a key role in carotenoid absorption. Therefore, this work was designed to highlight the relationship between processed food microstructure and carotenoid absorption. This study aimed to evaluate the consumption of a carotenoid-rich fruit snack on lipid profile, glycemia and especially on carotenoid absorption/bioconversion in Wistar rats. Animals were fed with mixtures based on vacuum-fried papaya chips with either soy oil (PC-S) or palm oil (PC-P) during 7 days, receiving 0.29 mg lycopene/kg/day and 0.35 mg total carotenoids/kg/day. Lycopene and retinoids were analyzed in plasma and liver of rats by HPLC-DAD. Results showed that the consumption of mixtures based on papaya chips did not affect the lipid profile or glycemia in rat plasma, regardless the type of oil. Wide-field and confocal microscopy analyses of food matrix helped to understand why lycopene accumulation in the liver was higher (p < 0.05) in rats fed with PC-P (0.442 µg/g liver) than in those fed with PC-S (0.291 µg/g liver). A better dissolution of crystalloid lycopene was found in PC-P. Conversely, a higher bioconversion of provitamin A carotenoids was observed for soy products. The effect of type of oil was underlined by epifluorescence microscopy of papaya mixtures showing homogeneous and small lipid droplets for soy products. These results showed that PC-S could be recommanded as a healthy snack, being a source of provitamin A carotenoids and bioavailable lycopene in a diversified diet.

Influence of nutrients on the bioaccessibility and transepithelial transport of polybrominated diphenyl ethers measured using an in vitro method and Caco-2 cell monolayers

Previous research has shown the absorption of polybrominated diphenyl ethers (PBDEs) in the human gastrointestinal tract, but limited attention has been given to the influence of nutrients on PBDE absorption from food matrices. We investigated the effects of nutrients (oil, starch, protein, and dietary fiber) on the absorption and transport of PBDEs in a Caco-2 cell model and bioaccessibility of PBDEs by an in vitro gastrointestinal digestion method. The results showed that the accumulation ratios of PBDE congeners in Caco-2 cells were higher in the nutrient addition groups (oil: 26.7-50.6%, starch: 27.0-58.7%, protein: 12.1-44.1%, and dietary fiber: 28.2-55.1%) than the control group (7.17-36.1%), whereas the transport ratios were lower (oil: 2.30-7.20%, starch: 1.55-9.15%, protein: 1.04-8.78%, and dietary fiber: 0.85-7.04%) than control group (3.78-11.1%). Additionally, the PBDE bioaccessibility could be increased by adding the nutrients, particularly oil and starch. This study clarified the differences in PBDE absorption in the presence of nutrients using the in vitro digestion and Caco-2 cell model. The findings showed that nutrients were an important factor that promoted PBDE absorption in the gastrointestinal tract. Therefore, it is important to focus on a novel dietary strategy of food consumption with contaminant compounds to protect human health.

Advances in edible nanoemulsions: Digestion, bioavailability, and potential toxicity

The design, fabrication, and application of edible nanoemulsions for the encapsulation and delivery of bioactive agents has been a highly active research field over the past decade or so. In particular, they have been widely used for the encapsulation and delivery of hydrophobic bioactive substances, such as hydrophobic drugs, lipids, vitamins, and phytochemicals. A great deal of progress has been made in creating stable edible nanoemulsions that can increase the stability and efficacy of these bioactive agents. This article highlights some of the most important recent advances within this area, including increasing the water-dispersibility of bioactives, protecting bioactives from chemical degradation during storage, increasing the bioavailability of bioactives after ingestion, and targeting the release of bioactives within the gastrointestinal tract. Moreover, it highlights progress that is being made in creating plant-based edible nanoemulsions. Finally, the potential toxicity of edible nanoemulsions is considered.

Chili Pepper Carotenoids: Nutraceutical Properties and Mechanisms of Action

Chili pepper is a prominent cultivated horticultural crop that is traditionally used for food seasoning and is applied for the treatment and prevention of multiple diseases. Its beneficial health properties are due to its abundance and variety of bioactive components, such as carotenoids, capsaicinoids, and vitamins. In particular, carotenoids have important nutraceutical properties, and several studies have focused on their potential in the prevention and treatment of human diseases. In this article, we reviewed the state of knowledge of general aspects of chili pepper carotenoids (biosynthesis pathway, types and content in Capsicum spp., and the effects of processing on carotenoid content) and recent findings on the effects of carotenoid nutraceuticals, such as antioxidant, cancer preventive, anti-inflammatory, cardiovascular disorder preventive, and anti-obesity effects.

Addition of either gastric lipase or cholesterol esterase to improve both β-cryptoxanthin ester hydrolysis and micellarization during in vitro digestion of fruit pulps

Using the INFOGEST in vitro digestion protocol adapted to carotenoids, the impact of additional rabbit gastric lipase (RGL) on the hydrolysis extent of β-cryptoxanthin esters was evaluated for the first time, and compared with the addition of porcine cholesterol esterase (CEL). Both the modifications increased the hydrolysis of (all-E)-β-cryptoxanthin esters from mandarin and peach pulps, although the outcomes were different. Addition of RGL consistently increased the average hydrolysis extent from 55.2% to 59.5% in mandarin pulp and from 22.7% to 48.8% in peach pulp (p < 0.05). The addition of CEL produced lower hydrolysis extents, i.e., 58.5% in mandarin (not statistically significant) and 28.4% in peach (p < 0.05), compared to those obtained with RGL. The hydrolysis extent positively correlated with the carotenoid ester concentration in both matrices. Bioaccessibility values were higher in mandarin pulp (range 32-34%) compared to those in peach pulp (range 16-21%), and were associated with the hydrolysis extent of the carotenoid esters during digestion. Addition of RGL and CEL produced no significant (p < 0.05) effect on the overall carotenoid bioaccessibility values of mandarin, while positively affected those in peach. Altogether these results corroborate that the hydrolysis extent of xanthophyll esters limits bioaccessibility. Additionally, hydrophobicity of the carotenoid inversely correlates with micellarization, as free (all-E)-xanthophylls micellarized in a higher extent compared to (all-E)-β-carotene and xanthophyll esters. The new information of our results is that the addition of rabbit gastric lipase substantially contributes to the hydrolysis of β-cryptoxanthin esters from fruit pulps, and consequently, to increase carotenoid bioaccessibility, being even more effective than CEL.

Determination of water-soluble vitamins and carotenoids in Brazilian tropical fruits by High Performance Liquid Chromatography

Vitamins are organic compounds essential for normal physiological functioning and they need to be provided in adequate amounts by the diet. They are nutrients mainly associated to fruit consumption, playing an important role in the cellular function, growth and development of individuals. The present study aimed to analyze levels of vitamins B, C and carotenoids of fruits from the agrobiodiversity of Northeastern Brazil, among them cajuí (Anacardium spp), murici (Byrsonima crassifolia (L.) Kunth), pequi (Caryocar coriaceum Wittm.), jenipapo (Genipa americana L.), mangaba (Hancornia speciosa Gomes), bacuri (Platonia insignis Mart.), cajá (Spondias mombin L.), umbu-cajá (Spondias bahiensis P. Carvalho, Van den Berg & M. Machado), umbu (Spondias tuberosa Arruda), pitanga (Eugenia uniflora L.), araçá (Psidium sobralianum Landrum & Proença). The vitamins were quantified using the analytical method High Performance Liquid Chromatography (HPLC). Vitamin B complex levels varied from 0.003 ± 0.01 mg/100 g to 6.107 ± 0.06 mg/100 g. Vitamin C ranged from 0.36 ± 0.06 mg/100 g to 253.92 ± 9.02 mg/100 g. Carotenoid values ranged from 0.12 ± 0.02 μg/100 g to 395.63 ± 113.69 μg/100 g. Thus, the profile of water-soluble vitamins and carotenoids of the fruits analyzed was quantified. Therefore, these fruits can provide varied amounts of vitamins important to human health. However, it is interesting for the individual to consume fruits in a diversified manner, avoiding monotony and thus guaranteeing the daily intake of more nutrients.

Development of a Gemini Interfacial Antioxidant for Oil in Water Emulsion with Gallic Acid and Dodecyl Gemini Chains

In this study, development of the gemini gallate (GG) interfacial antioxidant for oil in water (O/W) emulsion was performed employing Steglich esterification with gallic acid and dodecyl gemini chains through a prepacked column and peristaltic pump-based purification system. The structural identity and purity of the prepared GG and monogallate (MG) were confirmed by NMR, Fourier transform infrared spectroscopy, and high-performance liquid chromatography-mass spectrometry. Further evaluation revealed that the GG possessed excellent radical scavenging activity and superior antioxidant activity in an O/W emulsion relative to the MG, especially under the condition of a reduced amount of the emulsifier. Microscopic investigation by a fluorescent probe and transmission electron microscopy (TEM) unveiled that the extraordinary antioxidant performance in the O/W emulsion was presumably attributed to preferable interfacial location because of the unique gemini molecular architecture. The superior antioxidant activity of the gemini antioxidant holds great promise for antioxidation in O/W emulsions.

A Brief Overview of Dietary Zeaxanthin Occurrence and Bioaccessibility

As it exhibits no provitamin A activity, the dietary intake of zeaxanthin is not considered essential. However, its contribution to ocular health has long been acknowledged. Numerous publications emphasize the importance of zeaxanthin alongside lutein in ocular diseases such as cataracts and age-related macular degeneration which constitute an important health concern, especially among the elderly. Considering that the average dietary ratio of lutein to zeaxanthin favors the first, more bioaccessible food sources of zeaxanthin that can hinder the development and progression of the above-mentioned disorders are of great interest. In this paper, a brief overview of the more recent state of knowledge as regards dietary sources together with their respective zeaxanthin bioaccessibility assessed through a standardized in vitro digestion method was provided.

Nutraceutical nanodelivery; an insight into the bioaccessibility/bioavailability of different bioactive compounds loaded within nanocarriers

Nanofoods is a current concept that is based on the application of nanotechnologies in the preparation of safe foods, with superior nutritional and sensory characteristics, and capable of providing multiple health benefits. In line with the principles of this concept, food scientists have focused on developing new types of nano biosystems that can contribute to increasing the bioavailability of bioactive compounds used in food fortification. Numerous research teams have investigated the main factors limiting oral bioavailability including: bioaccessibility, absorption and transformation of bioactive compounds and bioactive-loaded nanocarriers. The physicochemical processes involved in the factors limiting oral bioavailability have been extensively studied, such asthe release, solubility and interaction of bioactive compounds and nanocarriers during food digestion, transport mechanisms of bioactive compounds and nanoparticles through intestinal epithelial cells as well as the chemical and biochemical transformations in phase I and phase II reactions. In this comprehensive review, the physicochemical processes involved in the bioaccessibility/bioavailability of different encapsulated bioactive compounds, that play an important role in human health, will be explained including polyphenols, phytosterols, carotenoids, vitamins and minerals. In particular, the mechanisms involved in the cellular uptake of bioactive-loaded nanocarriers including transcellular transport (diffusion, endocytosis, pinocytosis, transcytosis, phagocytosis), paracellular transport (through the "tight junctions" between epithelial cells), and the active transport of bioactive compounds under the action of membrane transporters are highlighted.

The role of vitamin A and its pro-vitamin carotenoids in fetal and neonatal programming: gaps in knowledge and metabolic pathways

Vitamin A (VA) and its pro-vitamin carotenoids are naturally occurring lipophilic compounds involved in several cellular processes and metabolic pathways. Despite their broad spectrum of activities in the general population, dietary deficiencies of these compounds can potentially affect pregnancy outcomes. Since maternal nutritional status and diet composition during pregnancy and lactation can have long-lasting effects in offspring until adulthood, this study presents an overview of VA and the role of pro-VA carotenoids during pregnancy and lactation – the nutrition, metabolism, and biological effects in the offspring. The review aimed to discuss the pro-VA carotenoids and VA-associated pathways and summarize the results with reference to gestational disorders, and VA and pro-VA carotenoids as preventive agents. Also, considering that obesity, overweight, and metabolic diseases are major public health concerns worldwide, fetal and neonatal development is discussed, highlighting the physiological role of these molecules in obesity prevention. This review comprehensively summarizes the current data and shows the potential impact of these compounds on nutritional status in pregnancy and lactation.

Impact of onions in tomato-based sauces on isomerization and bioaccessibility of colorless carotenes: phytoene and phytofluene

Onions as an interesting ingredient have been proved to promote Z-isomerization of lycopene and increase bioaccessibility of total-lycopene. Phytoene (PT) and phytofluene (PTF), the precursors of lycopene, are colorless carotenes, which are attracting much attention and are also abundant in tomatoes. Therefore, onions might also affect the distribution and bioaccessibility of PT and PTF isomers during heating tomato (hot-break and cold-break purees)-onion-extra virgin olive oil (EVOO) sauces. The addition of onions (or diallyl disulfide present in onions) into tomato purees did not cause degradation of PT or PTF; however it favored E/Z-isomerization of PT and PTF by reducing the proportions of their natural Z-isomers (Z-15-PT and Z2,3-PTF) and decreased the bioaccessibility of total-PT and total-PTF. Simultaneously, a complex picture was obtained for the effect of onions on the bioaccessibility of individual PT and PTF isomers, depending on the precise isomer. Bioaccessibility of PT and PTF isomers in tomato-based sauces decreased in the order: 15-Z-PT > all-E-PT; Z2,3-PTF > all-E-PTF > Z4 or Z5-PTF; total-PT > total-PTF. E-isomerization of PT and PTF enhanced by onions during heating tomato-onion purees decreased their bioaccessibility.

Bile amount affects both the degree of micellarization and the hydrolysis extent of carotenoid esters during in vitro digestion

Carotenoid esters are present in considerable amounts in most fruits, such as in citrus. Although the bioavailability of carotenoid esters is similar or even higher compared to that of free carotenoids, these molecules are generally detected only in the free form in human plasma, suggesting that hydrolysis of carotenoid esters occurs in vivo. However, the available in vitro digestion methods were not able to achieve satisfactory carotenoid ester hydrolysis so far. As bile salts play an essential role in the hydrolytic action of lipolytic enzymes from pancreatin, we evaluated the effect of increasing the bile extract/food ratio from 0.045 to 0.12 (g g-1) on the hydrolysis of β-cryptoxanthin esters from mandarin pulp during in vitro digestion. Additionally, considering the positive effect of lipids on carotenoid bioavailability, the impact of soybean oil addition on carotenoid ester hydrolysis was studied. Finally, bioaccessibility and recovery of 33 carotenoids were assessed by LC-DAD-MS. The hydrolysis extent of β-cryptoxanthin esters enhanced from 29% to 55% by increasing the bile extract/food ratio, but reduced respectively to 28% and 11% by the addition of 1% and 10% oil (p < 0.05). The bioaccessibility of overall carotenoids improved from 19% to 35% by increasing the bile extract/food ratio, along with that of (all-E)-β-carotene (from 19 to 31%) and total (all-E)-β-cryptoxanthin (17% to 49%). Soybean oil addition reduced carotenoid micellarization, regardless of the concentration (p < 0.05). Irrespective of the bile extract amount and oil addition, the bioaccessibility of carotenoids was inversely related to its hydrophobicity, with respect to the following ranking: free xanthophylls > carotenes ≥ xanthophyll esters. Altogether, these results indicate that increasing the bile extract amount is a simple and inexpensive option to improve carotenoid ester hydrolysis in in vitro digestion protocols. Additionally, the constant amounts of bile (and possibly enzymes) of static methods, such as INFOGEST, should be further optimized for experiments involving lipid addition in which carotenoid bioaccessibility is evaluated.

Enhancing Efficacy, Performance, and Reliability of Cannabis Edibles: Insights from Lipid Bioavailability Studies

The legal sale of cannabis-enriched foods and beverages for medical or recreational purposes is increasing in many states and countries, especially in North America and Europe. These food-based cannabis delivery systems vary considerably in their compositions and structures, ranging from low-viscosity watery beverages to solid fatty chocolates. The rate and extent of release of the bioactive components in cannabis within the human gastrointestinal tract (GIT) affect their health and psychoactive effects. Studies with other types of hydrophobic bioactives, such as nutraceuticals and vitamins, have shown that food composition and structure have a major impact on their bioaccessibility, transformation, and absorption within the GIT, thereby influencing their bioavailability and bioactivity. This review outlines how insights on the bioavailability of other lipophilic bioactives can be used to facilitate the design of more efficacious and consistent cannabis-enriched products intended for oral consumption. In particular, the importance of food-matrix composition (such as fat type and level) and structural organization (such as fat domain dimensions) are discussed.

Impact of Pesticide Type and Emulsion Fat Content on the Bioaccessibility of Pesticides in Natural Products

There is interest in incorporating nanoemulsions into certain foods and beverages, including dips, dressings, drinks, spreads, and sauces, due to their potentially beneficial attributes. In particular, excipient nanoemulsions can enhance the bioavailability of nutraceuticals in fruit- and vegetable-containing products consumed with them. There is, however, potential for them to also raise the bioavailability of undesirable substances found in these products, such as pesticides. In this research, we studied the impact of excipient nanoemulsions on the bioaccessibility of pesticide-treated tomatoes. We hypothesized that the propensity for nanoemulsions to raise pesticide bioaccessibility would depend on the polarity of the pesticide molecules. Bendiocarb, parathion, and chlorpyrifos were therefore selected because they have Log P values of 1.7, 3.8, and 5.3, respectively. Nanoemulsions with different oil contents (0%, 4%, and 8%) were fabricated to study their impact on pesticide uptake. In the absence of oil, the bioaccessibility increased with increasing pesticide polarity (decreasing Log P): bendiocarb (92.9%) > parathion (16.4%) > chlorpyrifos (2.8%). Bendiocarb bioaccessibility did not depend on the oil content of the nanoemulsions, which was attributed to its relatively high water-solubility. Conversely, the bioaccessibility of the more hydrophobic pesticides (parathion and chlorpyrifos) increased with increasing oil content. For instance, for chlorpyrifos, the bioaccessibility was 2.8%, 47.0%, and 70.7% at 0%, 4%, and 8% oil content, respectively. Our findings have repercussions for the utilization of nanoemulsions as excipient foods in products that may have high levels of undesirable non-polar substances, such as pesticides.

Characterization and the impact of in vitro simulated digestion on the stability and bioaccessibility of carotenoids and their esters in two Pouteria lucuma varieties

Lucuma is a starchy orange-yellow fruit native to the Andean region. It is widely consumed in Latin America and has been recently adapted to the agronomical characteristics of the south region of Spain. However, its carotenoid profile has never been reported. The aim of this study was to characterize the carotenoid and carotenoid ester composition of lucuma pulps (var. Molina and Beltran) and assess their bioaccessibility with an in vitro simulated gastrointestinal digestion according to the INFOGEST® methodology. The carotenoid profile in lucuma pulps revealed a high qualitative diversity composed of 33 compounds, corresponding to 9 free xanthophylls, 9 hydrocarbon carotenes and 15 xanthophyll esters. (13Z)-violaxanthin, (all-E)-violaxanthin and (all-E)-antheraxanthin were the most abundant carotenoids in lucuma fruits and were naturally present as xanthophyll esters: (all-E)-antheraxanthin 3-O-palmitate, (all-E)-violaxanthin laurate and (all-E)-violaxanthin palmitate. Carotenoids were stable during in vitro digestion; however, their release from the food matrix was limited which contributed to their low bioaccessibility.

Impact of calcium levels on lipid digestion and nutraceutical bioaccessibility in nanoemulsion delivery systems studied using standardized INFOGEST digestion protocol

The bioaccessibility of hydrophobic bioactives may be greatly reduced in the presence of calcium.

Evaluation of the protein and bioactive compound bioaccessibility/bioavailability and cytotoxicity of the extracts obtained from aquaculture and fisheries by-products

Bioavailability, bioaccessibility, bioactivity and cytotoxicity define if a bioactive compound obtained from aquaculture and associated by-products can be assimilated and used for the body in a safe and efficient way. Four models are used to evaluate the bioavailability: in vitro (simulated gastrointestinal digestion using intestinal epithelial Caco-2 cell cultures); ex vivo (gastrointestinal organs or organoids in laboratory conditions); in situ (intestinal perfusion in animals) and in vivo (animal studies and human studies). In vitro models are very effective, predicting in vivo actions since they evaluate multiple conditions regardless physiological effects. However, in vivo systems are essential for the validation of the results. The use of a combined model between human digestion and cell culture-based models would solve these difficulties, allowing valid conclusions. These studies must be completed with the evaluation of cytotoxicity and oxidative stress markers, providing most accurate results regarding the adverse effect on the body. These methods would test the effect of food structure, food composition, dietary factors and the effect of food processing on bioavailability. Further studies should be carried out to establish a standardized method and achieve a balance between the use of in vivo and in vitro systems.

Fabrication of Curcumin-Loaded Dairy Milks Using the pH-Shift Method: Formation, Stability, and Bioaccessibility

The pH-shift method is a simple approach for incorporating certain kinds of polyphenol-based nutraceuticals into already existing colloidal systems. The polyphenols can be loaded into hydrophobic particles due to the fact that their water-solubility is relatively high under alkaline conditions but low under acid or neutral conditions. In this study, it was demonstrated that bovine milk could be enriched with curcumin using this approach, without adversely affecting milk fat globule stability. The storage stability of the curcumin-enriched bovine milk was assessed when samples were incubated for 60 days at different pH values and temperatures. The pH-stability was determined by storing curcumin-enriched milk at 4 °C for 60 days at pH 6.5, 7.0, and/or 8.0. At this low storage temperature, all milk samples were stable to fat globule aggregation, creaming, curcumin degradation (<13% loss), and color loss. The temperature-stability was determined by storing curcumin-enriched milk at pH 7 for 15 days at 4, 20, 37, or 55 °C. Curcumin breakdown decreased with decreasing storage temperature: 55 °C (43%) > 37 °C (21%) > 20 °C (10%) > 4 °C (5%). Interestingly, the color of the curcumin-enriched milks incubated at 4, 20, and 37 °C remained similar to that of the initial samples, but the sample stored at 55 °C showed significant color fading. Curcumin bioaccessibility determined using an in vitro gastrointestinal tract was around 40%, which was attributed to some chemical degradation and binding of the curcumin reducing its stability and solubilization. This study shows that a hydrophobic nutraceutical (curcumin) can be loaded into dairy milk products using a simple method, which could facilitate the creation of novel functional foods and beverages.

Liberation and Micellarization of Carotenoids from Different Smoothies after Thermal and Ultrasound Treatments

The consumption of a varied diet rich in fruit and vegetables helps prevent and treat certain chronic diseases. The development of smoothies based on derivatives from fruit and vegetables rich in bioactive compounds can help increase the consumption of these foods, and therefore, contribute to the prevention of various health problems. However, during the processing of the fruit and vegetable smoothies, these properties may change. The elaboration of smoothies is based on fruits and vegetables rich in carotenoids: Carrot juice-papaya-mango (smoothie A) and carrot juice-pumpkin-mango (smoothie B). The objective of this study is to evaluate the impact of the application of different thermal technologies (mild and intensive heat treatment) and non-conventional technologies (ultrasound) on carotenoids (α-carotene, β-carotene, lutein and β-cryptoxantin) and determine the physiochemical parameters of derivatives from fruit and vegetable smoothies. In addition, the bioaccessibility of carotenoids is also evaluated through a process of in vitro simulated digestion. With regard to the bioaccessibility of the fruit and vegetable smoothies analyzed, a positive effect of temperature on liberation and micellarization was observed.

Chemical Composition and In Vitro Bioaccessibility of Antioxidant Phytochemicals from Selected Edible Nuts

The ultimate health benefits of peanuts and tree nuts partially depend on the effective gastrointestinal delivery of their phytochemicals. The chemical composition and in vitro bioaccessibility of tocopherols, tocotrienols and phenolic compounds from peanuts and seven tree nuts were evaluated by analytical and chemometric methods. Total fat and dietary fiber (g 100 g-1) ranged from 34.2 (Emory oak acorn) to 72.5 (pink pine nut; PPN) and from 1.2 (PPN) to 22.5 (pistachio). Samples were rich in oleic and linoleic acids (56-87 g 100 g-1 oil). Tocopherols and tocotrienols (mg·kg-1) ranged from 48.1 (peanut) to 156.3 (almond) and 0 (almond, pecan) to 22.1 (PPN) and hydrophilic phenolics from 533 (PPN) to 12,896 (Emory oak acorn); flavonoids and condensed tannins (mg CE.100 g-1) ranged from 142 (white pine nut) to 1833 (Emory oak acorn) and 14 (PPN) to 460 (Emory oak acorn). Three principal components explained 90% of the variance associated with the diversity of antioxidant phytochemicals in samples. In vitro bioaccessibility of tocopherols, tocotrienols, hydrophilic phenolics, flavonoids, and condensed tannins ranged from 11-51%, 16-79%, 25-55%, 0-100%, and 0-94%, respectively. Multiple regression analyses revealed a potential influence of dietary fiber, fats and/or unsaturated fatty acids on phytochemical bioaccessibility, in a structure-specific manner.

Improved Carotenoid Processing with Sustainable Solvents Utilizing Z-Isomerization-Induced Alteration in Physicochemical Properties: A Review and Future Directions

Carotenoids—natural fat-soluble pigments—have attracted considerable attention because of their potential to prevent of various diseases, such as cancer and arteriosclerosis, and their strong antioxidant capacity. They have many geometric isomers due to the presence of numerous conjugated double bonds in the molecule. However, in plants, most carotenoids are present in the all-E-configuration. (all-E)-Carotenoids are characterized by high crystallinity as well as low solubility in safe and sustainable solvents, such as ethanol and supercritical CO₂ (SC-CO₂). Thus, these properties result in the decreased efficiency of carotenoid processing, such as extraction and emulsification, using such sustainable solvents. On the other hand, Z-isomerization of carotenoids induces alteration in physicochemical properties, i.e., the solubility of carotenoids dramatically improves and they change from a “crystalline state” to an “oily (amorphous) state”. For example, the solubility in ethanol of lycopene Z-isomers is more than 4000 times higher than the all-E-isomer. Recently, improvement of carotenoid processing efficiency utilizing these changes has attracted attention. Namely, it is possible to markedly improve carotenoid processing using safe and sustainable solvents, which had previously been difficult to put into practical use due to the low efficiency. The objective of this paper is to review the effect of Z-isomerization on the physicochemical properties of carotenoids and its application to carotenoid processing, such as extraction, micronization, and emulsification, using sustainable solvents. Moreover, aspects of Z-isomerization methods for carotenoids and functional difference, such as bioavailability and antioxidant capacity, between isomers are also included in this review.

Iron, Catechin, and Ferulic Acid Inhibit Cellular Uptake of β-Carotene by Reducing Micellization

Green leafy vegetables have low β-carotene bioavailability, which we hypothesized to be, at least in part, due to high contents of fiber, minerals, and phenolics. We investigated the effects of pectin (40-120 μg/mL), iron (50-150 μg/mL), ferulic acid (30-90 μg/mL), and catechin (50-150 μg/mL), in a model system, on β-carotene micellization (in vitro digestion) and intestinal absorption (Caco-2 cell model). Iron, pectin, ferulic acid, and catechin on average reduced ( p < 0.05) β-carotene micellization (1.49 ± 0.05 μmol/L) by 66.9, 59.3, 43.2, and 51.7%, respectively. Iron reduced micellization by precipitating bile salts from solution and ferulic acid and catechin by inhibition of pancreatic lipase. β-Carotene uptake by Caco-2 cells (2.63 ± 0.22%) was reduced ( p < 0.05) by 37.4, 70.1, 77.0, and 75.1%, respectively, when it was digested with pectin, iron, ferulic acid, or catechin. However, when individual test compounds were added to already micellized β-carotene, they did not inhibit β-carotene uptake. The large reductions in β-carotene micellization observed in vitro warrant further investigation in humans using model green leafy vegetable systems to elucidate their relevance under real-life conditions.