Effects of calcium on lipid digestion in nanoemulsions stabilized by modified starch: Implications for bioaccessibility of β -carotene

Hyaluronic acid-poly(glyceryl)10-stearate nanoemulsion for co-delivery of fish oil and resveratrol: Enhancing bioaccessibility and antioxidant potency

Hyaluronic acid (HA), an endogenous polysaccharide comprising alternating D-glucuronic acid and N-acetylglucosamine units, is renowned for its high hydrophilicity, biocompatibility, and biodegradability. These attributes have rendered HA invaluable across medical and drug delivery fields. HA can be altered through physical, chemical, or enzymatic methods to improve the properties of the modified substances. In this work, we synthesized a derivative via the esterification of HA with poly(glyceryl)10-stearate (PG10-C18), designated as HA-PG10-C18. This novel derivative was employed to fabricate a nano co-delivery system (HA-PG10-C18@Res-NE) for fish oil and resveratrol (Res), aiming to enhance their stability and bioaccessibility. An exhaustive investigation of HA-PG10-C18@Res-NE revealed that the HA-modified system displayed superior physicochemical stability, notably in withstanding oxidation and neutralizing free radicals. Moreover, in vitro simulated digestion underscored the system's enhanced bioaccessibility of Res and more efficient release of free fatty acids. These outcomes underscore the strategic advantage of HA in modifying PG10-C18 for nanoemulsion formulation. Consequently, HA-PG10-C18 stands as a promising emulsifier for encapsulating lipophilic bioactives in functional foods, nutraceuticals, and pharmaceuticals.

Water-in-oil Pickering emulsion using ergosterol as an emulsifier solely

As a crucial component of the fungal cell membranes, ergosterol has been demonstrated to possess surface activity attributed to its hydrophobic region and polar group. However, further investigation is required to explore its emulsification behavior upon migration to the oil-water interface. Therefore, this study was conducted to analyze the interface properties of ergosterol as a stabilizer for water in oil (W/O) emulsion. Moreover, the emulsion prepared under the optimal conditions was utilized to load the water-soluble bioactive substance with the chlorogenic acid as the model molecules. Our results showed that the contact angle of ergosterol was 117.017°, and its dynamic interfacial tension was obviously lower than that of a pure water-oil system. When the ratio of water to oil was 4: 6, and the content of ergosterol was 3.5 % (ergosterol/oil phase, w/w), the W/O emulsion had smaller particle size (438 nm), higher apparent viscosity, and better stability. Meanwhile, the stability of loaded chlorogenic acid was improved under unfavorable conditions (pH 1.2, 90 °C, ultraviolet irradiation, and oxidation), which were 73.87 %, 59.53 %, 62.53 %, and 69.73 %, respectively. Additionally, the bioaccessibility of chlorogenic acid (38.75 %) and ergosterol (33.69 %), and the scavenging rates of the emulsion on DPPH radicals (81.00 %) and hydroxyl radicals (82.30 %) were also enhanced. Therefore, a novel W/O Pickering emulsion was prepared in this work using ergosterol as an emulsifier solely, which has great potential for application in oil-based food and nutraceutical formulations.

Advancements in lipid-based delivery systems for functional foods: a comprehensive review of literature and patent trends

Lipid-based delivery systems (LDS) have emerged as cornerstone techniques for bolstering the bioavailability of lipophilic bioactive compounds, addressing challenges related to solubility, stability, and absorption. This critical review examined a substantial dataset of 6,907 scientific articles and 3,021 patents from 2001-2023, elucidating the multifaceted evolution of LDS, with a particular focus on its industrial and patent-driven perspective. Notably, there were pronounced surges in functional food patent applications in 2004, 2011, and 2019. The trajectory revealed a shift from foundational nanoemulsions to more complex structures, such as double/multiple emulsions, solid lipid nanoparticles, Pickering emulsions, and bigels. The review further identified the top 10 leading institutions shaping this domain. Technologies like spray-drying, microfluidics, and phase gelation had revolutionized the landscape, resulting in refined sensory experiences, innovative reduced-fat formulations, enriched beverages, tailor-made infant nutrition, and nuanced release mechanisms for flavors. The review also spotlighted current research frontiers, notably Pickering emulsions, bigels, and multiple emulsions. These emerging technologies not only exemplified the ongoing innovation in the field but also underscored their potential in reshaping the future landscape of value-added functional foods.

Research progress on chitin/chitosan-based emulsion delivery systems and their application in lipid digestion regulation

Excessive lipid intake is linked to an elevated risk of health problems. However, reducing lipid contents may influence food structure and flavor. Some alternatives are needed to control the lipid absorption. Emulsions are common carriers for lipids, which can control the hydrolysis and absorption of lipids. Chitin (Ch) and chitosan (CS) are natural polysaccharides with good biodegradability, biocompatibility, and unique cationic properties. They have been reported to be able to delay lipolysis, which can be regarded as one of the most promising agents that regulates lipid digestion (LiD). The application of Ch/CS and their derivatives in emulsions are summarized in this review with a focus on their performances and mechanisms for LiD regulation, aiming to provide theoretical guidance for the development of novel Ch/CS emulsions, and the regulation of LiD. A reasonable design of emulsion interface can provide its resistance to the external environment and then control LiD. The properties of emulsion interface are the key factors affecting LiD. Therefore, systematic study on the relationship between Ch/CS-based emulsion structure and LiD can not only instruct the reasonable design of emulsion interface to accurately regulate LiD, but also provide scientific guidelines for applying Ch/CS in functional food, medicine and other fields.

Application of Curcumin Emulsion Carrier from Ultrasonic-Assisted Prepared Octenyl Succinic Anhydride Rice Starch

The emulsification of ultrasonic-assisted prepared octenyl succinic anhydride (OSA) rice starch on curcumin was investigated in the present study. The results indicated that the encapsulation efficiency of curcumin in emulsions stabilized by OSA-ultrasonic treatment rice starch was improved, from 81.65 ± 0.14% to 89.03 ± 0.09%. During the in vitro oral digestion, the particle size and Zeta potential of the curcumin emulsion did not change significantly (p > 0.05). During the in vitro digestive stage of the stomach and small intestine, the particle size of the curcumin emulsion continued to increase, and the absolute potential continued to decrease. Our work showed that OSA-pre-treatment ultrasonic rice starch could improve curcumin bioavailability by increasing the encapsulation efficiency with stronger stability to avoid the attack of enzymes and high intensity ion, providing a way to develop new emulsion-based delivery systems for bioactive lipophilic compounds using OSA starch.

Changes of physico-chemical properties of nano-biomaterials by digestion fluids affect the physiological properties of epithelial intestinal cells and barrier models

Background

The widespread use of nano-biomaterials (NBMs) has increased the chance of human exposure. Although ingestion is one of the major routes of exposure to NBMs, it is not thoroughly studied to date. NBMs are expected to be dramatically modified following the transit into the oral-gastric-intestinal (OGI) tract. How these transformations affect their interaction with intestinal cells is still poorly understood. NBMs of different chemical nature—lipid-surfactant nanoparticles (LSNPs), carbon nanoparticles (CNPs), surface modified Fe₃O₄ nanoparticles (FNPs) and hydroxyapatite nanoparticles (HNPs)—were treated in a simulated human digestive system (SHDS) and then characterised. The biological effects of SHDS-treated and untreated NBMs were evaluated on primary (HCoEpiC) and immortalised (Caco-2, HCT116) epithelial intestinal cells and on an intestinal barrier model.

Results

The application of the in vitro SDHS modified the biocompatibility of NBMs on gastrointestinal cells. The differences between SHDS-treated and untreated NBMs could be attributed to the irreversible modification of the NBMs in the SHDS. Aggregation was detected for all NBMs regardless of their chemical nature, while pH- or enzyme-mediated partial degradation was detected for hydroxyapatite or polymer-coated iron oxide nanoparticles and lipid nanoparticles, respectively. The formation of a bio-corona, which contains proteases, was also demonstrated on all the analysed NBMs. In viability assays, undifferentiated primary cells were more sensitive than immortalised cells to digested NBMs, but neither pristine nor treated NBMs affected the intestinal barrier viability and permeability. SHDS-treated NBMs up-regulated the tight junction genes (claudin 3 and 5, occludin, zonula occludens 1) in intestinal barrier, with different patterns between each NBM, and increase the expression of both pro- and anti-inflammatory cytokines (IL-1β, TNF-α, IL-22, IL-10). Notably, none of these NBMs showed any significant genotoxic effect.

Conclusions

Overall, the results add a piece of evidence on the importance of applying validated in vitro SHDS models for the assessment of NBM intestinal toxicity/biocompatibility. We propose the association of chemical and microscopic characterization, SHDS and in vitro tests on both immortalised and primary cells as a robust screening pipeline useful to monitor the changes in the physico-chemical properties of ingested NBMs and their effects on intestinal cells.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12989-022-00491-w.

Encapsulation of a Desmodium intortum Protein Isolate Pickering Emulsion of β-Carotene: Stability, Bioaccesibility and Cytotoxicity

Owing to their excellent characteristics, Pickering emulsions have been widely used in the development and the application of new carriers for embedding and for delivering active compounds. In this study, β-carotene was successfully encapsulated in a Pickering emulsion stabilized using Desmodium intortum protein isolate (DIPI). The results showed that the encapsulation efficiencies of β-carotene in the control group Tween 20 emulsion (TE) and the DIPI Pickering emulsion (DIPIPE) were 46.7 ± 2.5% and 97.3 ± 0.8%, respectively. After storage for 30 days at 25 °C and 37 °C in a dark environment, approximately 79.4% and 72.1% of β-carotene in DIPIPE were retained. Compared with TE, DIPIPE can improve the stability of β-carotene during storage. In vitro digestion experiments showed that the bioaccessibility rate of β-carotene in DIPIPE was less than that in TE. Cytotoxicity experiments showed that DIPI and β-carotene micelles within a specific concentration range exerted no toxic effects on 3T3 cells. These results indicate that DIPIPE can be used as a good food-grade carrier for embedding and transporting active substances to broaden the application of the protein-based Pickering emulsion system in the development of functional foods.

Biophysical insights into modulating lipid digestion in food emulsions

During the last decade, major scientific advances on understanding the mechanisms of lipid digestion and metabolism have been made, with a view to addressing health issues (such as obesity) associated with overconsumption of lipid-rich and sucrose-rich foods. As lipids in common foods exist in the form of emulsions, the structuring of emulsions has been one the main strategies for controlling the rate of lipid digestion and absorption, at least from a colloid science viewpoint. Modulating the kinetics of lipid digestion and absorption offers interesting possibilities for developing foods that can provide control of postprandial lipaemia and control the release of lipophilic compounds. Food emulsions can be designed to achieve considerable differences in the kinetics of lipid digestion but most research has been applied to relatively simple model systems and in in vitro digestion models. Further research to translate this knowledge into more complex food systems and to validate the results in human studies is required. One promising approach to delay/control lipid digestion is to alter the stomach emptying rate of lipids, which is largely affected by interactions of emulsion droplets with the food matrices. Food matrices with different responses to the gastric environment and with different interactions between oil droplets and the food matrix can be designed to influence lipid digestion. This review focuses on key scientific advances made during the last decade on understanding the physicochemical and structural modifications of emulsified lipids, mainly from a biophysical science perspective. The review specifically explores different approaches by which the structure and stability of emulsions may be altered to achieve specific lipid digestion kinetics.

The impact of the physical form of torularhodin on its metabolic fate in the gastrointestinal tract

Torularhodin is a fungal carotenoid with multiple health benefits. However, the relationship between its physical form and metabolic fate in the gastrointestinal tract (GIT), which is essential to its bioavailability and health efficacy, has rarely been studied. Thus, physical forms of torularhodin including nanoemulsion powder (T-EP), capsules of the T-EP by alginate (T-EPA), and solution in MCT oil (T-oil) were used in the study. T-EP was produced through OSA-starch-mediated torularhodin emulsification and spray drying whereas the T-EPA was alginate-based capsules of the T-EP particles that were entrapped in the network structure of the alginate matrix as observed by scanning electron microscopy (SEM). The oil digestibility in the simulated small intestine was decreased from T-EP (100%), T-oil (60%) to T-EPA (40%), and the bioaccessibilities were 27%, 15% and 12%, respectively. The in vivo study using mice revealed that the content of torularhodin gradually decreased along with the digestion time in both the stomach and small intestine while a significantly higher colonic accumulation was observed in T-EPA compared to T-oil and T-EP. In vitro fecal fermentation showed that propionate (32 mM) was the predominant metabolite produced by torularhodin in the physical form of T-EPA. Thus, the physical form of torularhodin is a significant contributing factor to its GIT metabolic fate, and a health outcome-oriented design of the physical form of torularhodin or other nutraceuticals is beneficial for the development of functional foods with enhanced health benefits.

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 Cellular Absorption and Metabolism of β-Carotene Loaded in Nanocarriers after In Vitro Digestion

Three protein emulsifiers encapsulating β-carotene (BC) with accompanying lipids into nanoemulsions (NEs) or without lipids into nanoparticles (NPs) were fabricated to study the effect of the type of interfacial protein on carrier design and the structure remodeling during digestion on the overall uptake and metabolism of BC in Caco-2 cells. BC-loaded micelles and micellar-like aggregates were collected after in vitro digestion and applied to Caco-2 cell monolayers. The digestion process significantly enhanced the cellular uptake of BC by 1.2-2.2 times and 4.1-8.2 times loaded in NEs and NPs, respectively. Whey protein isolate-based carriers improved the absorption but decreased the metabolism of BC to retinyl palmitate. The presence of lipids was found to improve metabolism and aid the transport of retinoids to the basolateral side of Caco-2 monolayers. Understanding the transportation behavior of the protein-based nanocarries after digestion may contribute to the design of biosafe carriers with higher bioavailability to deliver lipophilic nutrients.

Role of calcium on lipid digestion and serum lipids: a review

Calcium is an essential nutrient for humans that can be taken as supplement or in a food matrix (e.g. dairy products). It is suggested that dietary calcium may have a beneficial effect on cardiovascular risk but the mechanism is not clear. In this review, the main mechanisms of the possible cholesterol-lowering effect of calcium, i.e. interaction with fatty acids and bile acids, are described and clinical evidences are presented. The observations from interventional studies of the possible cholesterol-lowering effect in terms of the main related mechanisms are variable and do not seem to fulfill all the related aspects. It seems that the interplay of calcium in blood lipid metabolism might be due to its complex and multiple roles in the lipid digestion in the small intestine. The interactions between calcium and, fatty acids and bile may lead to impaired mixed micelle formation and solubilization, which is crucial in the lipid absorption and metabolism. In addition, the calcium source and its surrounding matrix will have an influence over the physiological outcome. This research is important for the delivery and formulation of calcium, particularly with the move toward plant-based diets.

Structural modification of whey protein isolate by cinnamaldehyde and stabilization effect on β-carotene-loaded emulsions and emulsion gels

The effect of cinnamaldehyde (CA) on the structure and properties of whey protein isolate (WPI) was investigated. The resultant WPI/CA complex was used as stabilizer to form emulsions and emulsion gels, which were used for the delivery and protection of β-carotene. The particle size and hydrophobicity of WPI solution increased and then decreased with the addition of CA. Circular dichroism showed that CA mainly changed the secondary structure of WPI, with increasing β-fold content from 47.2% to 72.9%. The fluorescence spectra showed that both tryptophan and tyrosine in WPI were involved in the interaction with CA. WPI/CA complex as the stabilizer could form the stable emulsions and emulsion gels, which showed better protection effect on β-carotene, and helped enhance its bioaccessibility. The knowledge provides insights into the development of new multifunctional food ingredients and the enhancement of protein modification in food system.

Grape seed proanthocyanidin-loaded gel-like W/O/W emulsion stabilized by genipin-crosslinked alkaline soluble polysaccharides-whey protein isolate conjugates: Fabrication, stability, and in vitro digestion

The present work aims to fabricate the genipin-crosslinked alkaline soluble polysaccharides-whey protein isolate conjugates (G-AWC) to stabilize W/O/W emulsions for encapsulation and delivery of grape seed proanthocyanidins (GSP). After crosslinking reaction, the molecular weight was increased and surface hydrophobicity was decreased. Then, the G-AWC and polyglycerol polyricinoleate (PGPR, a lipophilic emulsifier) were employed to prepare a GSP-loaded W/O/W emulsion with the addition of gelatin and sucrose in W₁ phase via a two-step procedure. Creamed emulsion could be fabricated at W₁/O volume fraction (Φ) of 10%-70% and further increased Φ to 75% or even up to 90% could obtain gel-like emulsion with notably elastic behaviors. In the W₁/O/W₂ emulsion with Φ of 80%, the encapsulation efficiency (EE) of GSP reached up to 95.86%, and decreased by ca. 10% after a week of storage. Moreover, the encapsulated GSP in the emulsion showed a remarkably higher bioaccessibility (40.72%) compared to free GSP (13.11%) in the simulated gastrointestinal digestion. These results indicated that G-AWC-stabilized W/O/W emulsions could be an effective carrier to encapsulate water-soluble bioactive compounds with enhanced stability and bioaccessibility.

Starch-based materials encapsulating food ingredients: Recent advances in fabrication methods and applications

Encapsulation systems have gained significant interest in designing innovative foods, as they allow for the protection and delivery of food ingredients that have health benefits but are unstable during processing, storage and in the upper gastrointestinal tract. Starch is widely available, cheap, biodegradable, edible, and easy to be modified, thus highly suitable for the development of encapsulants. Much efforts have been made to fabricate various types of porous starch and starch particles using different techniques (e.g. enzymatic hydrolysis, aggregation, emulsification, electrohydrodynamic process, supercritical fluid process, and post-processing drying). Such starch-based systems can load, protect, and deliver various food ingredients (e.g. fatty acids, phenolic compounds, carotenoids, flavors, essential oils, irons, vitamins, probiotics, bacteriocins, co-enzymes, and caffeine), exhibiting great potentials in developing foods with tailored flavor, nutrition, sensory properties, and shelf-life. This review surveys recent advances in different aspects of starch-based encapsulation systems including their forms, manufacturing techniques, and applications in foods.

Fate of β-Carotene within Loaded Delivery Systems in Food: State of Knowledge

Nanotechnology has opened new opportunities for delivering bioactive agents. Their physiochemical characteristics, i.e., small size, high surface area, unique composition, biocompatibility and biodegradability, make these nanomaterials an attractive tool for β-carotene delivery. Delivering β-carotene through nanoparticles does not only improve its bioavailability/bioaccumulation in target tissues, but also lessens its sensitivity against environmental factors during processing. Regardless of these benefits, nanocarriers have some limitations, such as variations in sensory quality, modification of the food matrix, increasing costs, as well as limited consumer acceptance and regulatory challenges. This research area has rapidly evolved, with a plethora of innovative nanoengineered materials now being in use, including micelles, nano/microemulsions, liposomes, niosomes, solidlipid nanoparticles, nanostructured lipids and nanostructured carriers. These nanodelivery systems make conventional delivery systems appear archaic and promise better solubilization, protection during processing, improved shelf-life, higher bioavailability as well as controlled and targeted release. This review provides information on the state of knowledge on β-carotene nanodelivery systems adopted for developing functional foods, depicting their classifications, compositions, preparation methods, challenges, release and absorption of β-carotene in the gastrointestinal tract (GIT) and possible risks and future prospects.

Stability, Interfacial Structure, and Gastrointestinal Digestion of β-Carotene-Loaded Pickering Emulsions Co-stabilized by Particles, a Biopolymer, and a Surfactant

Novel Pickering emulsions were stabilized by complex interfaces in the presence of zein colloidal particles (ZCPs), propylene glycol alginate (PGA), and rhamnolipid (Rha) for delivery of β-carotene. The influence of the particle-surfactant, particle-biopolymer, and particle-biopolymer-surfactant mixed interfaces on the physiochemical properties and digestion fate of Pickering emulsions was investigated. It is the first time that three different types of emulsifiers have been used to synergistically stabilize food Pickering emulsions for delivery of lipophilic nutraceuticals. The physicochemical stability, microstructure, rheological properties, and in vitro gastrointestinal digestion of Pickering emulsions were controlled by the addition sequence and mass ratio of multiple stabilizers, which showed the enhanced stability and delayed lipid digestion of the particle-biopolymer-surfactant-stabilized Pickering emulsions. After encapsulation into Pickering emulsions, the retention rate of β-carotene increased 2-fold under UV radiation for 8 h. The coexistence of ZCPs, PGA, and Rha could induce the competitive displacement, multilayer deposition, and interparticle network at the interface. The combination of particles, a biopolymer, and a surfactant delayed the lipolysis during in vitro gastrointestinal tract. By modulating the interfacial composition, the release rate of free fatty acids from Pickering emulsions was reduced from 19.46% to 2.83% through different mechanisms. The novel Pickering emulsion could be incorporated in foods as well as pharmaceuticals for controlled lipid digestion or targeted nutrient delivery purposes.

Improving the bioavailability of oil-soluble vitamins by optimizing food matrix effects: A review

The potency of oil-soluble vitamins (vitamins A, D, E and K) in fortified foods can be improved by understanding how food matrices impact their bioavailability. In this review, the major food matrix effects influencing the bioavailability of oil-soluble vitamins are highlighted: oil content, oil composition, particle size, interfacial properties, and food additives. Droplet size and aggregation state in the human gut impact vitamin bioavailability by modulating lipid digestion, vitamin release, and vitamin solubilization. Vitamins in small isolated oil droplets typically have a higher bioavailability than those in large or aggregated ones. Emulsifiers, stabilizers, or texture modifiers can therefore affect bioavailability by influencing droplet size or aggregation. The dimensions of the hydrophobic domains in mixed micelles depends on lipid type: if the domains are too small, vitamin bioavailability is low. Overall, this review highlights the importance of carefully designing food matrices to improve vitamin bioavailability.

Remodeling of β-Carotene-Encapsulated Protein-Stabilized Nanoparticles during Gastrointestinal Digestion In Vitro and in Mice

The remodeling of β-carotene-encapsulated protein nanoparticles (NPs) during digestion in vitro and in vivo was investigated. The NPs were formed using three different proteins. Hydrolysis of the surface protein during digestion resulted in structure remodeling of NPs and the formation of small-sized micellar-like aggregates below 100 nm, accelerating the release of β-carotene into the aqueous phase. However, the reduced surface ζ-potential in the intestinal fluid suggested the adsorption of bile salts, favoring the formation of small-sized micellar-like aggregates. A shifted peak of β-carotene in the micellar phase from 965 cm^-1 to about 855 cm^-1 in Fourier transform infrared spectroscopy analysis indicated that β-carotene existed in the amorphous state. Microstructure observation in vivo further confirmed that β-carotene was loaded in micellar-like aggregates and dispersed uniformly in water. The cellular uptake study showed that the absorption rate of digested NPs was significantly increased by 1.34- to 4.16-fold when compared with undigested NPs.

Chitosan reduces vitamin D bioaccessibility in food emulsions by binding to mixed micelles

Consumption of sufficiently high quantities of dietary fibers has been linked to a range of health benefits. Recent research, however, has shown that some dietary fibers interfere with lipid digestion, which may reduce the bioavailability of oil-soluble vitamins and nutraceuticals. For this reason, we examined the impact of a cationic polysaccharide (chitosan) on the bioaccessibility of vitamin D using the standardized INFOGEST in vitro digestion model. The vitamin D was encapsulated within an emulsion-based delivery system that contained whey protein-coated corn oil droplets. Our results showed that chitosan promoted severe droplet flocculation in the small intestine and reduced the amount of free fatty acids detected using a pH-stat method. However, a back-titration of the digested sample showed that the lipids were fully digested at all chitosan levels used (0.1-0.5%), suggesting that chitosan may have bound some of the free fatty acids released during lipid digestion. The presence of the chitosan decreased the bioaccessibility of vitamin D by about 37%, but this effect did not depend strongly on chitosan concentration (0.1-0.5%). It was hypothesized that chitosan bound to the vitamin-loaded mixed micelles and promoted their precipitation. The knowledge gained in this study might provide useful insights in designing emulsion-based delivery systems with high vitamin bioaccessibility.

Construction of octenyl succinic anhydride modified porous starch for improving bioaccessibility of β-carotene in emulsions

Modified porous starch (PS), by introducing octenyl succinic anhydride (OSA) moieties, was synthesized successfully, which was applied as an emulsion of β-carotene for the first time. The pores and channels within porous starch provided more possibilities for OSA to modify starch. The ester linkage of OSA modified PS with different degrees of substitution (DS) were confirmed by both ¹³C solid-state NMR and Fourier transform-infrared spectroscopy (FT-IR). The hydrophobic octenyl succinic and hydrophilic hydroxyl groups of OSA modified PS showed the good emulsifying capability, which could be utilized to prepare β-carotene emulsions. And the bioaccessibility of β-carotene was also enhanced with increasing DS of OSA modified starch. This study not only paves a new way using porous starches for modification of starch, but also offers an attractive alternative for obtaining emulsion-based delivery systems for bioactive components.

The synthesis and application of OSA modified porous starch.

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.

A stable high internal phase emulsion fabricated with OSA-modified starch: an improvement in β-carotene stability and bioaccessibility

A high internal phase emulsion (HIPE) was firstly fabricated with octenyl succinic anhydride modified starch through simple shear dispersion.

Impact of plant extract on the gastrointestinal fate of nutraceutical-loaded nanoemulsions: phytic acid inhibits lipid digestion but enhances curcumin bioaccessibility

The impact of phytic acid on lipid digestion and curcumin bioaccessibility in oil-in-water nanoemulsions was investigated using a simulated gastrointestinal tract (GIT).

Encapsulation of pterostilbene in nanoemulsions: influence of lipid composition on physical stability, in vitro digestion, bioaccessibility, and Caco-2 cell monolayer permeability

Nanoemulsions fabricated using medium chain triglycerides as carrier lipid are more effective for delivering pterostilbene than long chain triglycerides.

Preparation and characterization of nanoemulsion based β-carotene hydrogels

The aim of this study was to develop β-carotene hydrogels using nanoemulsions, with increased β-carotene aqueous solubility, bioavailability and improved physical and chemical stabilities. The nanoemulsion of β-carotene was prepared using a solvent-displacement technique and converted into hydrogels using sodium alginate as stabilizer and calcium chloride as cross-linker. The effects of formulation parameters, mainly, the effects sodium alginate and calcium chloride concentrations on the physicochemical properties of hydrogels were evaluated using a surface response methodology. The second order polynomial equations, subsequently, were suggested to predict the changes of studied physicochemical characteristics of hydrogels, with relatively high regression of coefficients values. Based on numerical multiple optimization, it was concluded that using 4.1 g/l sodium alginate and 5.7 g/l calcium chloride, resulted in a hydrogel with the most desired physicochemical characteristics. No significant differences between the measured and predicted data, reconfirmed the accuracy of the models.

Improved stability, epithelial permeability and cellular antioxidant activity of β-carotene via encapsulation by self-assembled α-lactalbumin micelles

The low aqueous solubility, stability and bioavailability of hydrophobic bioactive compounds, such as β-carotene (β-c), greatly hinder their application in foods. Nanocarriers could overcome this problem by facilitating the delivery of the functional ingredients. We prepared lactalbumin (α-lac) micelles by partial enzymatic hydrolysis in aqueous solution. β-c can be incorporated into the cores of these micelles via hydrophobic interactions. The aqueous solubility and stability under 60 °C heating or UV light irradiation of encapsulated β-c improved significantly compared with free β-c. Moreover, it had an increased cellular uptake (3 times) and transmembrane permeability (13 times) in a Caco-2 cell monolayer model. It suggested that α-lac micelle-encapsulated β-c had an enhanced cellular absorption and transport efficiency. Encapsulated β-c also exhibited an enhanced cellular anti-oxidant activity (CAA) compared with free β-c. This work demonstrates that α-lac micelles showed a great potential for delivery of hydrophobic bioactive compounds in foods.