In vitro and in vivo study of the enhancement of carotenoid bioavailability in vegetables using excipient nanoemulsions: Impact of lipid content

Enhancing bioactive compounds in plant-based foods: Influencing factors and technological advances

Plant-based foods are natural sources of phytochemicals, which exhibit free radical scavenging capacity. However, the bioaccessibility of phytochemicals in foods are limited due to their poor stability and solubility within food matrix. Moreover, chemical degradation induced by processing further diminish the levels of these bioactive compounds. This review explores the impacts of thermal and non-thermal processing on fruits and vegetables, emphasizing the application of emerging technologies to enhance food quality. Innovative non-thermal technologies, which align with sustainable and environmentally friendly principles of green development, are particularly promising. Supercritical CO2 and cold plasma can be applied in extraction of phytochemicals, and these extracts also can be used as natural preservatives in food products, as well as improve the texture and sensory properties of food products, offering significant potential to advance the field of food science and technology while adhering to eco-friendly practices.

In vitro digestive behavior of emulsifier-stabilized excipient emulsions affects the bioaccessibility of flavonoids

BACKGROUND

Flavonoids, found in common vegetables and fruits, have health benefits that are often limited by their low bioavailability. Excipient emulsions provide an effective strategy to overcome these obstacles. However, the nature of the emulsifier used to formulate excipient emulsions and the chemical structure of the flavonoids both affect the bioaccessibility of the flavonoids.

RESULTS

The purpose of this study was to investigate the impact of the interfacial properties of excipient emulsions on the in vitro gastrointestinal fate of representative structural flavonoids (quercetin, kaempferol, and apigenin) through the INFOGEST method. Tween 80 (TW80) (a nonionic surfactant) was more effective at reducing the oil-water interfacial tension than whey protein isolate (WPI) (a protein-based emulsifier) or octenyl succinic anhydride (OSA)-modified starch (MS) (a polysaccharide-based emulsifier). Moreover, TW80 created excipient emulsions with smaller oil droplets, which were more resistant to oral and gastric conditions. The WPI-emulsions underwent severe flocculation in the gastric phase, leading to an appreciable increase in particle size (from 220 to 3000 nm). The TW80-coated oil droplets were more digestible than WPI- or MS-coated ones. This was attributed to the larger lipid surface area for lipase attachment. The bioaccessibility of quercetin, kaempferol, and apigenin was also affected by emulsifiers: TW 80 (25% to 45%) > WPI (14% to 29%) ≈ MS (15% to 25%). Flavonoid bioaccessibility appeared to be related to their molecular properties.

CONCLUSION

This study provides guidance for the design of effective excipient emulsions to enhance the bioavailability of flavonoids. © 2024 Society of Chemical Industry.

Effect of pectin structure on the in vitro bioaccessibility of carotenoids in simulated juice model

The impact of pectin structure on carotenoid bioaccessibility is still uncertain. This study aims to investigate how the different pectic polymers affected the bioaccessibility of carotenoids in a simulated juice model during static in vitro digestion. This study includes homogalacturonan (HG), which is a linear pectic polymer, rhamnogalacturonan-I (RG-I), which is a branched pectic polymer, and rhamnogalacturonan (RG), which is a diverse pectic polymer rich in RG-I, rhamnogalacturonan-II (RG-II), and xylogalacturonan domains. Juice models without pectin had the highest carotenoid bioaccessibility, suggesting pectin has negative effects on carotenoid bioaccessibility. During the intestinal phase, systems with HG showed the highest viscosity, followed by systems with RG and systems with RG-I. Systems with RG-I had lower carotenoid bioaccessibility than systems with HG and RG-II. Both the percentage of RG-I and the average side chain length of RG-I had negative correlations with carotenoid bioaccessibility. RG-I side chains with more arabinose and/or galactose might cause lower carotenoid bioaccessibility in this juice model system. This study offers valuable insights into the relationship between pectin structure and carotenoid bioaccessibility in a simulated juice model, highlighting the importance of considering pectin composition for maximizing carotenoid bioaccessibility and potential health benefits in fruit-based beverages.

Food nanoemulsions: how simulated gastrointestinal digestion models, nanoemulsion, and food matrix properties affect bioaccessibility of encapsulated bioactive compounds

Food nanoemulsions are known as very effective and excellent carriers for both lipophilic and hydrophilic bioactive compounds (BCs) and have been successfully used for controlled delivery and protection of BCs during gastrointestinal digestion (GID). However, due to sensitive and fragile morphology, BCs-loaded nanoemulsions have different digestion pathways depending on their properties, food matrix properties, and applied models for testing their digestibility and BCs bioaccessibility. Thus, this review gives a critical review of the behavior of encapsulated BCs into food nanoemulsions during each phase of GID in different static and dynamic in vitro digestion models, as well as of the influence of nanoemulsion and food matrix properties on BCs bioaccessibility. In the last section, the toxicity and safety of BCs-loaded nanoemulsions evaluated on in vitro and in vivo GID models have also been discussed. Better knowledge of food nanoemulsions' behavior in different models of simulated GI conditions and within different nanoemulsion and food matrix types can help to standardize the protocol for their testing aiming for researchers to compare results and design BCs-loaded nanoemulsions with better performance and higher targeted BCs bioaccessibility.

Emulsion-Based Delivery Systems to Enhance the Functionality of Bioactive Compounds: Towards the Use of Ingredients from Natural, Sustainable Sources

In recent years, the trend in the population towards consuming more natural and sustainable foods has increased significantly. This claim has led to the search for new sources of bioactive compounds and extraction methods that have less impact on the environment. Moreover, the formulation of systems to protect these compounds is also focusing on the use of ingredients of natural origin. This article reviews novel, natural alternative sources of bioactive compounds with a positive impact on sustainability. In addition, it also contains information on the most recent studies based on the use of natural (especially from plants) emulsifiers in the design of emulsion-based delivery systems to protect bioactive compounds. The properties of these natural-based emulsion-delivery systems, as well as their functionality, including in vitro and in vivo studies, are also discussed. This review provides relevant information on the latest advances in the development of emulsion delivery systems based on ingredients from sustainable natural sources.

Effect of the Emulsifier Used in Dunaliella salina-Based Nanoemulsions Formulation on the β-Carotene Absorption and Metabolism in Rats

SCOPE

Microalgae such as Dunaliella salina are a potential sustainable source of natural β-carotene due to their fast growth and high adaptability to environmental conditions. This work aims to evaluate the effect of the incorporation of β-carotene from this alga into different emulsifier-type nanoemulsions (soybean lecithin [SBL], whey protein isolate [WPI], sodium caseinate [SDC]) on its absorption, metabolization, and biodistribution in rats.

METHODS AND RESULTS

Nanoemulsions formulated with different emulsifiers at 8% concentration are obtained by five cycles of microfluidization at 130 mPa, then expose to an in vitro digestion or orally administer to rats. Feeding rats with nanoemulsions improves β-carotene uptake compared to control suspension, especially using SDC and WPI as emulsifiers. A greater presence of β-carotene and retinol in the intestine, plasma, and liver is observed, being the liver the tissue that shows the highest accumulation. This fact can be a consequence of the smaller droplets that protein-nanoemulsions present compared to that with SBL in the intestine of rats, which promote faster digestibility and higher β-carotene bioaccessibility (35%-50% more) according to the in vitro observations.

CONCLUSIONS

Nanoemulsions, especially those formulated with protein emulsifiers, are effective systems for increasing β-carotene absorption, as well as retinol concentration in different rat tissues.

In Vitro-In Vivo Study of the Impact of Excipient Emulsions on the Bioavailability and Antioxidant Activity of Flavonoids: Influence of the Carrier Oil Type

The influence of the carrier oil type on the bioavailability and bioactivity of flavonoids (quercetin, kaempferol, and apigenin) was examined using in vitro digestion, in situ intestinal perfusion, and pharmacokinetic studies. Here, medium-chain triglycerides (MCTs), long-chain triglycerides (LCTs), or MCT/LCT mixtures (1:1, w/w) served as the oil phase of excipient emulsions. Overall, the bioavailability and antioxidant activity of flavonoids increased when they were coingested with excipient emulsions. The in vitro bioaccessibility of flavonoids was affected by the carrier oil: LCT (17.9-22.8%) > MCT/LCT (12.1-13.7%) > MCT (9.2-12.6%). These differences were mainly attributed to the fact that the mixed micelles formed after the digestion of LCTs had larger hydrophobic domains to solubilize more flavonoids. However, in vivo pharmacokinetic experiments showed that the flavonoid concentrations in rat serum were comparable for all carrier oils (p > 0.05). Our results assist in formulating excipient emulsions to enhance the efficacy of flavonoids.

Research advances of in vivo biological fate of food bioactives delivered by colloidal systems

Food bioactives exhibit various health-promoting effects and are widely used in functional foods to maintain human health. After oral intake, bioactives undergo complex biological processes before reaching the target organs to exert their biological effects. However, several factors may reduce their bioavailability. Colloidal systems have attracted special attention due to their great potential to improve bioavailability and bioefficiency. Herein, we focus on the importance of in vivo studies of the biological fates of bioactives delivered by colloidal systems. Increasing evidence demonstrates that the construction, composition, and physicochemical properties of the delivery systems significantly influence the in vivo biological fates of bioactives. These results demonstrate the great potential to control the in vivo behavior of food bioactives by designing specific delivery systems. We also compare in vivo and in vitro models used for biological studies of the fate of food bioactives delivered by colloidal systems. Meanwhile, the significance of the gut microbiota, targeted delivery, and personalized nutrition should be carefully considered. This review provides new insight for further studies of food bioactives delivered by colloidal systems, as well as scientific guidance for the reasonable design of personalized nutrition.

Zein-Alginate-Phosphatidylcholine Nanocomplex Efficiently Delivers Lycopene and Lutein over Dietary-Derived Carotenoid Mixed Micelles in Caco-2 Cells

This study evaluated the potency of zein-alginate-phosphatidylcholine nanoparticles (NPs) on bioaccessibility/intestinal uptake of encapsulated lycopene (LY) and lutein (LT) versus dietary absorption using simulated digestion and human intestinal Caco-2 cells. LY-zein-alginate-PC (LYZAP) and LT-zein-alginate-PC (LTZAP) NPs yield desired properties, which exhibit sustained release and are suitable for oral administration. Interestingly, co-treatment of LYZAP + LTZAP showed better release of carotenoids instead of individual treatment at intestinal pH. Bioaccessibility, cellular uptake, and basolateral secretion of LY and LT from NPs were significantly enhanced than micellar carotenoids (dietary mode of absorption). The increased absorption of carotenoids from NPs correlated with triglyceride levels. The intestinal cell uptake of carotenoids by nanoencapsulation may be due to endocytosis, paracellular, and SRB-1 protein-mediated transport. Overall, LYZAP and LTZAP NPs possess superior properties to control the release and cellular uptake of unique or distinct carotenoids. The inclusion of alginate and phosphatidylcholine in zein-based nanoencapsulation could be a promising strategy to improve carotenoid bioavailability.

Mechanisms of carotenoid intestinal absorption and the regulation of dietary lipids: lipid transporter-mediated transintestinal epithelial pathways

Dietary lipids are key ingredients during cooking, processing, and seasoning of carotenoid-rich fruits and vegetables, playing vitals in affecting the absorption and utilization of carotenoids for achieving their health benefits. Besides, dietary lipids have also been extensively studied to construct various delivery systems for carotenoids, such as micro/nanoparticles, micro/nanoemulsions, and liposomes. Currently, the efficacies of these techniques on improving carotenoid bioavailability are often evaluated using the micellization rate or "bioaccessibility" based on in vitro models. However, recent studies have found that dietary lipids may also affect the carotenoid uptake via intestinal epithelial cells and the efflux of intracellular chyle particles via lipid transporters. An increasing number of studies reveal the varied impact of different dietary lipids on the absorption of different carotenoids and some lipids may even have an inhibitory effect. Consequently, it is necessary to clarify the relationship between the addition of dietary lipids and the intestinal absorption of carotenoid to fully understand the role of lipids during this process. This paper first introduces the intestinal absorption mechanism of carotenoids, including the effect of bile salts and lipases on mixed micelles, the types and regulation of lipid transporters, intracellular metabolizing enzymes, and the efflux process of chyle particles. Then, the regulatory mechanism of dietary lipids during intestinal carotenoid absorption is further discussed. Finally, the importance of selecting the dietary lipids for the absorption and utilization of different carotenoids and the design of an efficient delivery carrier are emphasized. This review provides suggestions for precise dietary carotenoid supplementation and offere an important reference for constructing efficient transport carriers for liposoluble nutrients.

Nano-enabled plant-based colloidal delivery systems for bioactive agents in foods: Design, formulation, and application

Consumers are becoming increasingly aware of the impact of their dietary choices on the environment, animal welfare, and health, which is causing many of them to adopt more plant-based diets. For this reason, many sectors of the food industry are reformulating their products to contain more plant-based ingredients. This article describes recent research on the formation and application of nano-enabled colloidal delivery systems formulated from plant-based ingredients, such as polysaccharides, proteins, lipids, and phospholipids. These delivery systems include nanoemulsions, solid lipid nanoparticles, nanoliposomes, nanophytosomes, and biopolymer nanoparticles. The composition, size, structure, and charge of the particles in these delivery systems can be manipulated to create novel or improved functionalities, such as improved robustness, higher optical clarity, controlled release, and increased bioavailability. There have been major advances in the design, assembly, and application of plant-based edible nanoparticles within the food industry over the past decade or so. As a result, there are now a wide range of different options available for creating delivery systems for specific applications. In the future, it will be important to establish whether these formulations can be produced using economically viable methods and provide the desired functionality in real-life applications.

Study on the digestive characteristics of short-and medium-chain fatty acid structural lipid and its rapid intervention on gut microbes: In vivo and in vitro studies

Structuring is a feasible scheme to improve lipids' value. Here, S_BL and S_LBL (C4-C12 structural lipids) were obtained through enzymatic ester-ester transesterification or acidolysis interesterification using glyceryl tributyrate/glyceryl tridodecanoate and lauric acid/glyceryl tributyrate as raw materials, respectively. The digestive characteristics of S_BL and S_LBL were investigated in vitro and in vivo, meanwhile, their effects on gut microbes were studied. Compared with their corresponding triglyceride physical mixture, S_BL possessed an ideal butyric acid sustained-release effect in simulated stomach digestion. Moreover, the sustained-release effect of S_LBL on glycerol monolaurate (GML) was revealed both in vivo and in vitro, while this effect of the S_BL was obviously occurred in small intestine. S_BL significantly increased the abundance of Bifidobacterium and S_LBL promoted the growth of Clostridiales within 24 h. Overall, both S_BL and S_LBL showed ideal sustained-release effects on GML rather than butyric acid, which may lead to positive changes in gut microbes.

Influence of Dietary Lipid Type on the Bioavailability of DDT and Its Metabolites in Soil: Mechanisms and Health Implications

The impact of dietary lipid type on DDTr (DDT and its metabolites) relative bioavailability (RBA) in soil was investigated using an in vivo mouse model and in vitro assays. Three different lipids were long chain triglycerides (LCT), medium chain triglycerides (MCT), and short chain triglycerides (SCT). DDTr-RBA markedly (p < 0.05) increased from 51.3 ± 10.8% (control) to 94.6 ± 15.9% (10% w/w LCT) and 112 ± 20.8% (20% LCT) in LCT amended treatments. A significant increase in DDTr-RBA (92.2 ± 9.84%, p < 0.05) was also observed when mice were administered diets containing 20% MCT; however, no influence on DDTr-RBA was observed for SCT amended diets. Mechanism exploration showed that LCT and MCT enhanced DDTr solubilization by a factor of 7.31-9.59 compared to controls as a consequence of micelle formation which promoted DDTr mobilization from soil. LCT significantly enhanced DDTr intestinal absorption via increasing synthesis and secretion of apolipoprotein B 48 (32.2 ± 2.08 mg/L), compared to MCT (22.1 ± 1.32 mg/L) and SCT (15.5 ± 2.03 mg/L) treated Caco-2 cells. Mouse gut microflora analysis highlighted that LCT and MCT may increase intestinal permeability by regulating abundance of Lactobacillus, which may influence the absorption of DDTr.

Future foods: Alternative proteins, food architecture, sustainable packaging, and precision nutrition

There are numerous challenges facing the modern food and agriculture industry that urgently need to be addressed, including feeding a growing global population, mitigating and adapting to climate change, decreasing pollution, waste, and biodiversity loss, and ensuring that people remain healthy. At the same time, foods should be safe, affordable, convenient, and delicious. The latest developments in science and technology are being deployed to address these issues. Some of the most important elements within this modern food design approach are encapsulated by the MATCHING model: Meat-reduced; Automation; Technology-driven; Consumer-centric; Healthy; Intelligent; Novel; and Globalization. In this review article, we focus on four key aspects that will be important for the creation of a new generation of healthier and more sustainable foods: emerging raw materials; structural design principles for creating innovative products; developments in eco-friendly packaging; and precision nutrition and customized production of foods. We also highlight some of the most important new developments in science and technology that are being used to create future foods, including food architecture, synthetic biology, nanoscience, and sensory perception.Supplemental data for this article is available online at https://doi.org/10.1080/10408398.2022.2033683.

Pickering emulsions stabilized by pea protein isolate-chitosan nanoparticles: fabrication, characterization and delivery EPA for digestion in vitro and in vivo

The work aimed to prepare pea protein isolate-chitosan (PPI-CS) nanoparticles, fabricate PPI-CS nanoparticles stabilized Pickering emulsions (PPI-CS Pickering emulsions) and deliver EPA for digestion in vitro and in vivo. The nanoparticles were characterized by scanning electron microscopy (SEM), and PPI-CS Pickering emulsions were characterized by physicochemical and rheological properties. The results showed that the size of PPI-CS nanoparticles was 194.22 ± 0.45 nm. Rheological measurement showed that the PPI-CS Pickering emulsions possessed a gel-like network. EPA encapsulated Pickering emulsions (EPA-PE, φ = 0.6) exhibited a high retention rate (93%) during storage and performed a lower release rate compared with EPA-PE (φ = 0.4) in vitro digestion. The area under the curve of EPA concentration of EPA-PE group and EPA-emulsions (EPA-Em) group was 1.71 and 1.48, respectively. It demonstrated that PPI-CS Pickering emulsions provided the possibility to deliver EPA for digestive absorption.

Comparison of Lutein Bioaccessibility from Dietary Supplement-Excipient Nanoemulsions and Nanoemulsion-Based Delivery Systems

The impact of lutein-loaded nanoemulsions and excipient nanoemulsions mixed with lutein-based dietary supplements (capsules and soft gels) on the bioaccessibility of lutein was explored using a simulated gastrointestinal tract (GIT). The particle size, particle size distribution, ζ-potential, microstructure, lipid digestibility, and lutein bioaccessibility of all the samples were measured after they were exposed to different environments (stomach and small intestine environments) within a simulated GIT. As expected, the bioaccessibility of lutein from the capsules (1.5%) and soft gels (3.2%) was relatively low when they were administered alone. However, the co-administration of excipient nanoemulsions significantly increased the bioaccessibility of lutein from both the capsules (35.2%) and soft gels (28.7%). This phenomenon was attributed to the fast digestion of the small oil droplets in the excipient nanoemulsions and the further formation of mixed micelles to solubilize any lutein molecules released from the supplements. The lutein-loaded nanoemulsions exhibited a much higher lutein bioaccessibility (86.8%) than any of the supplements, which was attributed to the rapid release and solubilization of lutein when the lipid droplets were rapidly and extensively digested within the small intestine. This study indicates that the bioaccessibility of lutein is much higher in nanoemulsion droplets than that in dietary supplements. However, consuming dietary supplements in the presence of nanoemulsion droplets can greatly increase lutein bioavailability. The results of this study have important guiding significance for the design of more effective lutein supplements.

Anti-aging properties of phytoconstituents and phyto-nanoemulsions and their application in managing aging-related diseases

Aging is spontaneous and inevitable process in all living beings. It is a complex natural phenomenon that manifests as a gradual decline of physiological functions and homeostasis. Aging inevitably leads to age-associated injuries, diseases, and eventually death. The research on aging-associated diseases aimed at delaying, preventing or even reversing the aging process are of great significance for healthy aging and also for scientific progress. Numerous plant-derived compounds have anti-aging effects, but their therapeutic potential is limited due to their short shelf-life and low bioavailability. As the novel delivery system, nanoemulsion can effectively improve this defect. Nanoemulsions enhance the delivery of drugs to the target site, maintain the plasma concentration for a longer period, and minimize adverse reaction and side effects. This review describes the importance of nanoemulsions for the delivery of phyto-derived compounds and highlights the importance of nanoemulsions in the treatment of aging-related diseases. It also covers the methods of preparation, fate and safety of nanoemulsions, which will provide valuable information for the development of new strategies in treatment of aging-related diseases.

Evaluation of the bioaccessibility of a carotenoid beadlet blend using an in vitro system mimicking the upper gastrointestinal tract

The release characteristics of a unique blend of carotenoid beadlets designed to increase bioavailability were tested using the dynamic gastrointestinal model TIM-1. Individual carotenoid bioaccessibility peaks were observed over approximately 3-4 hr in the order of lutein and zeaxanthin first, followed by lycopene, and then finally α- and β-carotene; when tested as a beadlet blend or when the beadlets were compressed into tablets. Bioaccessibility measurements of 7%-20% were similar to those previously reported in literature and comparable between the two formulations, beadlet blend and tablet formulations. Total recovery of carotenoids from all compartments ranged from 70% to 90% for all carotenoids, except lycopene where almost 50% was unrecoverable after digestion in the TIM system.