Preparation and characterization of corn starch-β-carotene composites

Starch-based materials for drug delivery in the gastrointestinal tract-A review

Starch is a natural copolymer with unique physicochemical characteristics. Historically, it has been physically, chemically, or enzymatically modified to obtain ad-hoc functional properties for its use in different applications. In this context, the use of starch-based materials in drug delivery systems (DDSs) has gained great attention mainly because it is cheap, biodegradable, biocompatible, and renewable. This paper reviews the state of the art in starch-based materials design for their use in drug-controlled release with internal stimulus responsiveness; i.e., pH, temperature, colonic microbiota, or enzymes; specifically, those orally administered for its release in the gastrointestinal tract (GIT). Physical-chemical principles in the design of these materials taking into account their response to a particular stimulus are discussed. The relationship between the type of DDSs structure, starch modification routes, and the corresponding drug release profiles are systematically analyzed. Furthermore, the challenges and prospects of starch-based materials for their use in stimulus-responsive DDSs are also debated.

Flavor-food ingredient interactions in fortified or reformulated novel food: Binding behaviors, manipulation strategies, sensory impacts, and future trends in delicious and healthy food design

With consumers gaining prominent awareness of health and well-being, a diverse range of fortified or reformulated novel food is developed to achieve personalized or tailored nutrition using protein, carbohydrates, or fat as building blocks. Flavor property is a critical factor in the acceptability and marketability of fortified or reformulated food. Major food ingredients are able to interact with flavor compounds, leading to a significant change in flavor release from the food matrix and, ultimately, altering flavor perception. Although many efforts have been made to elucidate how food matrix components change flavor binding capacities, the influences on flavor perception and their implications for the innovation of fortified or reformulated novel food have not been systematically summarized up to now. Thus, this review provides detailed knowledge about the binding behaviors of flavors to major food ingredients, as well as their influences on flavor retention, release, and perception. Practical approaches for manipulating these interactions and the resulting flavor quality are also reviewed, from the scope of their intrinsic and extrinsic influencing factors with technologies available, which is helpful for future food innovation. Evaluation of food-ingredient interactions using real food matrices while considering multisensory flavor perception is also prospected, to well motivate food industries to investigate new strategies for tasteful and healthy food design in response to consumers' unwillingness to compromise on flavor for health.

Formation, Structural Characterization, and Functional Properties of Corn Starch/Zeaxanthin Composites

Zeaxanthin is a natural xanthophyll carotenoid and the main macular pigment that protects the macula from light-initiated oxidative damage, but it has poor stability and low bioavailability. Absorption of this active ingredient into starch granules as a carrier can be used to improve both zeaxanthin stability and controlled release. Optimization using three variables judged important for optimizing the system (reaction temperature of 65 °C, starch concentration of 6%, and reaction time of 2 h) was conducted for incorporation of zeaxanthin into corn starch granules, aiming for high zeaxanthin content (2.47 mg/g) and high encapsulation efficiency (74%). Polarized-light microscopy, X-ray diffraction, differential scanning calorimetry, and Fourier transform infrared spectroscopy showed that the process partially gelatinized corn starch; additionally, it showed the presence of corn starch/zeaxanthin composites, with the zeaxanthin successfully trapped in corn starch granules. The half-life time of zeaxanthin in corn starch/zeaxanthin composites increased to 43 days as compared with that of zeaxanthin alone (13 days). The composites show a rapid increase in zeaxanthin release with in vitro intestinal digestion, which is favorable for possible use in living systems. These findings could have application in designing effective starch-based carriers of this bioactive ingredient with enhanced storage stability and improved intestines-targeted controlled-release delivery.

Improved stability of β-carotene by encapsulation in SHMP-corn starch aerogels

This study aimed to prepare a starch-based aerogel with microporous network structure, and to investigate its physicochemical properties after β-carotene encapsulation. Corn starch aerogels (CSA) prepared with sodium hexametaphosphate (SHMP) as a cross-linking agent and β-carotene encapsulation were evaluated in terms of morphology, long- and short-range molecular order, bioavailability, and stability. After encapsulating β-carotene, the morphology of SHMP-CSA showed that the aerogels presented agglomeration, and the relative crystallinity increased from 17.2% to 22.2%. The characteristic bands of β-carotene were not found in the FT-IR pattern, and the short-range molecular order of aerogel was decreased, proving that β-carotene was well embedded in the aerogel. During the simulated in vitro release process, β-carotene was almost completely released. After ultraviolet or light irradiation, the retention rate of β-carotene was much higher than that in the control group. These results demonstrated that SHMP-CSA encapsulation could effectively improve the stability of β-carotene.

Formulation Approaches to Crystalline Status Modification for Carotenoids: Impacts on Dissolution, Stability, Bioavailability, and Bioactivities

Carotenoids, including carotenes and xanthophylls, have been identified as bioactive ingredients in foods and are considered to possess health-promoting effects. From a biopharmaceutical perspective, several physicochemical characteristics, such as scanty water solubility, restricted dissolution, and susceptibility to oxidation may influence their oral bioavailability and eventually, their effectiveness. In this review, we have summarized various formulation approaches that deal with the modification of crystalline status for carotenoids, which may improve their physicochemical properties, oral absorption, and biological effects. The mechanisms involving crystalline alteration and the typical methods for examining crystalline states in the pharmaceutical field have been included, and representative formulation approaches are introduced to unriddle the mechanisms and effects more clearly.

Natural carriers: Recent advances in their use to improve the stability and bioaccessibility of food active compounds

In the last decades, the incorporation of bioactive compounds in food supplements aroused the attention of scientists. However, these ingredients often exhibit both low solubility and stability and their poor bioaccessibility within the gastrointestinal tract limits their effectiveness. To overcome these drawbacks, many carriers have been investigated for encapsulating nutraceuticals and enhancing their bioavailability. It is note that several different vegetable wall materials have been applied to build delivery systems. Considering their encapsulation mechanism, lipid and protein-based carriers display specific interaction patterns with bioactives, whereas polysaccharidic-based carriers can entrap them by creating porous highly stable networks. To maximize the encapsulation efficiency, mixed systems are very promising. Following the current goal of using natural and sustainable ingredients, only a limited number of studies about the isolation of new ingredients from agro-food waste are available. In this review, a comprehensive overview of the state of art in the development of innovative natural lipid-, protein- and polysaccharide-based plant carriers is presented, focusing on their application as food active compounds. Different aspects to be considered in the design of delivery systems are discussed, including the carrier structure and chemical features, the interaction between the encapsulating and the core material, and the parameters affecting bioactives entrapment.

Biocomposites of Epoxidized Natural Rubber Modified with Natural Substances

This research aimed to show the possible impact of natural antioxidants on epoxidized natural rubber (ENR) and poly(lactic acid) (PLA) green composites. Thus, the ENR/PLA blends were prepared with the addition of three selected phytochemicals (catechin hydrate, eugenol and flavone). Obtained materials were submitted for solar aging. The analysis of the samples’ features revealed that catechin hydrate is a natural substance that may delay the degradation of ENR/PLA blends under the abovementioned conditions. The blend loaded with catechin hydrate presented stable color parameters (dE < 3 a.u.), the highest aging coefficient (K = 0.38 a.u.) and the lowest carbonyl index based on FT-IR data (CI = 1.56) from among all specimens. What is more, this specimen prolonged the oxidation induction time in comparison with the reference samples. Gathered data prove the efficiency of catechin hydrate as an anti-aging additive. Additionally, it was found that a specimen loaded with flavone changed its color parameters significantly after solar aging (dE = 14.83 a.u.) so that it would be used as an aging indicator. Eventually, presented eco-friendly ENR-based compositions may be applied in polymer technology where materials presenting specific properties are desirable.

Recent progresses in the delivery of β-carotene: From nano/microencapsulation to bioaccessibility

Beta-carotene (BC) as an efficient pro-vitamin is effective in improving vision, immune system and cognitive function as well as preventing coronary diseases and cancer. However, besides its poor chemical stability, the high lipophilic nature of BC reduces its dispersibility and consequently bioavailability which limits its application into food, pharmaceutical and nutraceuticals. Different carriers with vesicular or particulate structures have been studied and utilized for promoting BC solubility, dispersibility, and protection against diverse operational or environmental stresses and also controlling BC release and subsequent bioaccessibility. The current study, therefore reviews different micro/nanocarriers reported on BC encapsulation with special focusing on its bioavailability. Liposomal structures have been successfully used for enhancing BC stability and bioavailability. Besides, emulsion-based carriers including Pickering emulsions, nanoemulsions and microemulsions have been widely evaluated for BC encapsulation and protection. In addition, lipid-based nanoparticles and nanostructural carriers have also been applied successfully for this context. Moreover, gel structures including emulgels, hydrogels and oleogels are studied in some researches. Most of these delivery systems led to higher hydro-solubility and dispersibility of BC which consequently increased its bioavailability; thereupon could promote its application into food, cosmetic and nutraceutical products. However, for remarkable incorporation of BC and other bioactive compounds into edible products, the safety and toxicological aspects of these delivery system especially those designed in nano scale should be addressed in the further researches.

Structural and physicochemical properties of composites between starch nanoparticles and β-carotene prepared via nanoprecipitation

To apply starch nanoparticles (SNP) as host materials for β-carotene encapsulation, aqueous SNP dispersions (10, 25, 50, and 100 mg/10 mL) and β-carotene in acetone (10, 50, 100, 150, and 200 μg/mL) were mixed. The acetone in the mixture was evaporated to prepare SNP and β-carotene composites, which were homogeneously dispersed in aqueous media with over 90 % solubility. When SNP content was higher than 50 mg, over 80 % of β-carotene was encapsulated in the composite matrix. X-ray diffraction, nuclear magnetic resonance spectroscopy, and transmission electron microscopic analyses confirmed the micellar-shaped composite particles with diameters <120 nm and an amorphous structure. High SNP content in the composites enhanced β-carotene stability under extremely hot and acidic conditions as well as against ultraviolet rays and oxidation reactions. The encapsulated β-carotene was not readily released in simulated gastric fluid, but was gradually released in simulated intestinal fluid via SNP digestion in the composites.

Effects of potato and sweet potato flour addition on properties of wheat flour and dough, and bread quality

The effects of 10%-30% of wheat flour substitution with potato flour (PF) and sweet potato flour (SPF) on the flour and dough properties, the total polyphenol (TPC), and carotenoid contents (TCC) of bread, as well as their correlation with bread texture and starch digestibility, were investigated. With PF and SPF addition, the peak, breakdown, and setback viscosity of the flour decreased. The addition of PF and SPF reduced the dough formation and stabilization duration, as well as the hardness of the bread. The specific volume of the bread depended on the addition amount of PF and SPF. When the addition of PF and SPF was 15%, the bread had the lowest hardness and highest specific volume. The TPC and TCC in the bread depended on the added flour variety, and negatively influenced specific volume and positively influenced the content of resistant starch (RS).

Construction of ferulic acid modified porous starch esters for improving the antioxidant capacity

For exploration of a type of synthetic antioxidant dietary fiber (ADF), porous starch (PS), modified by esterification with ferulic acid (FA) moieties, was synthesized successfully, with different degree of substitution (DS). The ester linkage of FA modified PS was confirmed by ¹³C solid-state NMR and FT-IR. XRD analysis showed that starch ferulates had a different crystal structure from the V-type pattern of native starch, suggesting that the starch gelled during the esterification reaction, then re-crystallized into a different structure. Morphological studies revealed that FA modified PS esters had a different morphology of irregular beehive-like and dense fibrous-like structures compared with that of native starch. In vitro antioxidant assays showed that starch ferulates had excellent antioxidant capacity. In particular, FA modified PS esters had a much higher antioxidant capacity than free FA in the β-carotene–linoleic acid assay. This study has advanced the technology of using porous starches for modifying the biological activity of an antioxidant polyphenol. We expect this work would inspire further studies on the interactions of phenolics with other food ingredients in the food industry.

For exploration of a type of synthetic antioxidant dietary fiber (ADF), porous starch (PS), modified by esterification with ferulic acid (FA) moieties, was synthesized successfully, with different degree of substitution (DS).

Starch inclusion complex for the encapsulation and controlled release of bioactive guest compounds

The linear component of starch, especially amylose, is capable of forming inclusion complex (IC) with various small molecules. It could significantly modify the structure and properties of starch, and it could bring beneficial effects when bioactive compounds can be encapsulated. This review discusses the formation and characterization of the starch-guest IC and focuses on the recent developments in the use of starch ICs for the encapsulation and controlled release of bioactive guest compounds. A great number of guest compounds, such as lipids, aroma compounds, pharmaceuticals, and phytochemicals, were studied for their ability to be complexed with starch and/or amylose and some of the formed ICs were evaluated for the chemical stability improvement and the guest release regulation. Starch-guest ICs has a great potential to be a delivery system, as most existing studies demonstrated the enhancement on guest retention and the possibility of controlled release.

Improved stability and aqueous solubility of β-carotene via encapsulation in self-assembled bioactive oleanolic acid nanoparticles

Poor water solubility and stability of β-carotene (Car) greatly hinder its application in foods. Herein, naturally occurring bioactive oleanolic acid (OA) was used as a nanocarrier to overcome these shortcomings by fabricating Car-loaded OA nanoparticles (Car/OA NPs). Through optimization, the encapsulation efficiency and loading capacity reached 80.7% and 32.6%, respectively. Systematic characterization suggested that Car was successfully encapsulated, and hydrogen bonding and hydrophobic interactions are the main forces facilitating the self-assembly and encapsulation. Compared with free Car, Car/OA NPs exhibited significantly improved water dispersibility and enhanced stability against UV radiation, heat, ionic strength, and acidic conditions. Further, Car/OA NPs provided gastric protection, delayed-release in simulated gastric fluid (SGF) and controlled release in simulated intestinal fluid (SIF). Additionally, both OA NPs and Car/OA NPs showed markedly inherent hepatoprotective effects. This work demonstrates that OA NPs can be used as inherent bioactive nanocarriers to deliver hydrophobic nutrients and bioactive food components.

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.

Effects of the chemical and physical reaction conditions on the formation of nanocomposites made of starch and stearic acid

To evaluate the reaction conditions on the physicochemical properties of composites of starch and stearic acid, composites were prepared under reaction conditions that varied the starch concentration (0.5, 1, 3%), stearic acid addition level (5, 10, 25 mg), stearic acid addition rate (2, 4, 8, 16 mL/min), and temperature (70, 80, 90 °C). All conditions significantly impacted the recovery, mean particle size, and zeta potential of samples. Specifically, a higher starch concentration and temperature significantly increased the recovery of stearic acid, but the mean particle size of the composite increased with higher stearic acid addition level and starch concentration. Stearic acid content in the composite exhibited a significant correlation with zeta potential (r = 0.818, p = 0.001). During enzymatic digestion for 20 min, 8% of the stearic acid was released from the composite. Approximately 10 % of the stearic acid was degraded after 36 h of storage at 50°C under 75 % relative humidity.

Natural Compounds as Sustainable Additives for Biopolymers

In the last few decades, the interest towards natural compounds, coming from a natural source and biodegradable, for biopolymers is always increasing because of a public request for the formulation of safe, eco-friendly, and sustainable materials. The main classes of natural compounds for biopolymers are: (i) naturally occurring fillers (nFil), such as nano-/micro- sized layered alumino-silicate: halloysite, bentonite, montmorillonite, hydroxyapatite, calcium carbonate, etc.; (ii) naturally occurring fibers (nFib), such as wood and vegetable fibers; (iii) naturally occurring antioxidant molecules (nAO), such as phenols, polyphenols, vitamins, and carotenoids. However, in this short review, the advantages and drawbacks, considering naturally occurring compounds as safe, eco-friendly, and sustainable additives for biopolymers, have been focused and discussed briefly, even taking into account the requests and needs of different application fields.

Encapsulation and stabilization of β-carotene by amylose inclusion complexes

In the present study, we report a novel composition based on amylose (or starch) inclusion complex with an amphiphilic material as an effective encapsulation platform technology to incorporate guests of interest. Specifically, the encapsulation of β-carotene in amylose-surfactant and amylose/starch-ascorbyl palmitate (AscP) inclusion complexes was investigated. Surfactants of different hydrophilicity/lipophilicity were selected to cover a broad range of HLB values. The formation of the inclusion complexes was characterized by X-ray diffraction and differential scanning calorimetry. The ability of amylose-surfactant system to encapsulate β-carotene was dependent on the HLB value of the surfactants, instead of their ability to induce inclusion complexation. The incorporation of β-carotene hindered amylose-surfactant inclusion complex formation, whereas no significant effect was observed on structural and thermal properties of starch-AscP inclusion complex in the presence of β-carotene. The X-ray diffraction pattern of amylose-AscP-β-carotene showed that β-carotene molecules did not crystallize into a separated phase and thus were suggested to be homogeneously immobilized within the polycrystalline amylose-AscP inclusion complexes. During a storage period of six weeks at 20 and 30°C, the stability of β-carotene was improved by encapsulation in starch-AscP inclusion complexes compared with that in physical mixtures of the three components.