Preparation and characterization of octenyl succinylated starch microgels via a water-in-oil (W/O) inverse microemulsion process for loading and releasing epigallocatechin gallate

Structural properties and antioxidant capacity of different aminated starch-phenolic acid conjugates

Different aminated starch (AS) [EEAS (introducing ethylenediamine into starch using cross-linking-etherification-amination method (CEA)), EPAS (introducing o-phenylenediamine using CEA), OEAS (introducing ethylenediamine using cross-linking-oxidation-amination method (COA)), and OPAS (introducing o-phenylenediamine using COA)] were synthesized. The AS-phenolic acids [gallic acid (GA), syringic acid (SA), and vanillic acid (VA)] conjugates were prepared by laccase-catalyzed reaction. The grafting efficiency of EEAS on GA, SA, and VA was 36.59%, 69.71%, and 68.85%, respectively. SA reduced the maximum depolymerization rate of EEAS. The relative crystallinity of EEAS and EPAS grafted phenolic acid increased, and their particles showed severe breakage in appearance. OEAS-phenolic acid conjugates lost its granular structure and behaved as flakes and lumps, while the surface of OPAS-phenolic acid conjugates remained smooth after grafting phenolic acid. GA increased the DPPH· scavenging efficiency of EEAS from 16.12% to 79.92%. The increased antioxidant capacity of the conjugates suggested that AS-phenolic acids conjugates have high potential for applications.

Bioactive compounds delivery and bioavailability in structured edible oils systems

The health benefits of bioactive compounds are dependent on the amount of intake as well as on the amount of these compounds that become bioavailable and bioaccessible. Various systems have been developed to deliver and increase the bioaccessibility of bioactive compounds. This review explores the impact of gelled (oleogels, bigels, emulgels, emulsions, hydrogels, and hydrogel beads), micro-(gels, particles, spheres, capsules, emulsions, and solid lipid microparticles) and nanoencapsulated systems (nanoparticles, solid lipid nanoparticles, nanostructured lipid carriers, nanoemulsions, liposomes, and nanoliposomes) on the digestibility and bioavailability of lipophilic and hydrophilic bioactives. Structurant molecules, the oil type, antioxidants, emulsifiers, and coatings in delivery systems with promising potential in food applications are critically discussed. The release and bio-accessibility of bioactive compounds in gelled systems are influenced by various factors, such as the type and concentration of gelators, the gelator-to-oil ratio, the type of antioxidant, the network of the system, and its hydrophobicity. The stability, bioaccessibility, and controlled release of bioactives were improved in structured emulsions. Several variables, including wall material, oil/water ratios, encapsulation process, and pH conditions, can affect the bioactives release in microencapsulated systems. Factors like coating type and core-to-wall ratio impact the stability and release of core components. The encapsulating material, the encapsulation technology, and the nature of the nanomaterials all have an impact on the bioaccessibility of nanoencapsulated systems. Nanoliposomes provide enhanced stability and absorption. In general, all encapsulated systems have shown great potential in improving the distribution and availability of bioactive compounds.

Novel a-linolenic acid emulsions stabilized by octenyl succinylated starch -soy protein-epigallocatechin-3-gallate complexes: Characterization and antioxidant analysis

In this study, octenyl succinylated starch (OSAS)-soy protein (SP)-epigallocatechin-3-gallate (EGCG) complexes were designed to enhance the physical and oxidative stability of α-linolenic acid emulsions. Formations of OSAS-SP-EGCG complexes were confirmed via particle size, ξ-potential, together with fourier transform infrared (FTIR). A mixing ratio of 1:2 for OSAS to SP-EGCG resulted in ternary complexes with the highest contact angle (59.69°), indicating the hydrophobicity. Furthermore, the characteristics of α-linolenic acid emulsions (oil phase volume fractions (φ) of 10% and 20%) stabilized by OSAS-SP-EGCG complexes were investigated, including particle size, ξ-potential, emulsion stability, oxidative stability, and microstructure. These results revealed exceptional physical stability together with enhanced oxidative stability for these emulsions. Particularly, emulsions utilizing complexes having a 1:2 OSAS to SP-EGCG ratio exhibited superior emulsion stability. These findings provide theoretical support to the development of emulsions containing high levels of α-linolenic acid and for the broader application of α-linolenic acid in food products.

Comparison and analysis of mechanism of β-lactoglobulin self-assembled gel carriers formed by different gelation methods

Based on the findings of our previous studies, a comprehensive comparative investigation of the quality and formation mechanism of gels obtained from protein self-assemblies induced by different methods is necessary. Self-assembled heat-induced gels had higher gel mechanical strength, and hydrophobic interactions played a greater role. Whether or not heat treatment was used to induce gel formation may play a more important role than the effect of divalent cations on gel formation. Hydrogen bonds played an important role in all gels formed using different gelation methods. Furthermore, Self-assembled cold-induced gels were considered to can load bioactive substances with different hydrophilicity properties due to the high water-holding capacity and the smooth, dense microstructure. Therefore, β-lactoglobulin fibrous and worm-like self-assembled cold-induced gels as a delivery material for hydrophilic bioactive substances (epigallocatechin gallate, vitamin B2) and amphiphilic bioactive substance (naringenin), with good encapsulation efficiency (91.92 %, 97.08 %, 96.72 %, 96.52 %, 98.94 %, 97.41 %, respectively) and slow-release performance.

Formation and Application of Starch-Polyphenol Complexes: Influencing Factors and Rapid Screening Based on Chemometrics

Understanding the nuanced interplay between plant polyphenols and starch could have significant implications. For example, it could lead to the development of tailor-made starches for specific applications, from bakinag and brewing to pharmaceuticals and bioplastics. In addition, this knowledge could contribute to the formulation of functional foods with lower glycemic indexes or improved nutrient delivery. Variations in the complexes can be attributed to differences in molecular weight, structure, and even the content of the polyphenols. In addition, the unique structural characteristics of starches, such as amylose/amylopectin ratio and crystalline density, also contribute to the observed effects. Processing conditions and methods will always alter the formation of complexes. As the type of starch/polyphenol can have a significant impact on the formation of the complex, the selection of suitable botanical sources of starch/polyphenols has become a focus. Spectroscopy coupled with chemometrics is a convenient and accurate method for rapidly identifying starches/polyphenols and screening for the desired botanical source. Understanding these relationships is crucial for optimizing starch-based systems in various applications, from food technology to pharmaceutical formulations.

Recent progress in promoting the bioavailability of polyphenols in plant-based foods

Polyphenols are important constituents of plant-based foods, exhibiting a range of beneficial effects. However, many phenolic compounds have low bioavailability because of their low water solubility, chemical instability, food matrix effects, and interactions with other nutrients. This article reviews various methods of improving the bioavailability of polyphenols in plant-based foods, including fermentation, natural deep eutectic solvents, encapsulation technologies, co-crystallization and amorphous solid dispersion systems, and exosome complexes. Several innovative technologies have recently been deployed to improve the bioavailability of phenolic compounds. These technologies may be utilized to increase the healthiness of plant-based foods. Further research is required to better understand the mechanisms of action of these novel approaches and their potential to be used in food production.

Cell Staining Microgels Derived from a Natural Phenolic Dye: Hematoxylin Has Intriguing Biomedical Potential

Hematoxylin (HT) as a natural phenolic dye compound is generally used together with eosin (E) dye as H&E in the histological staining of tissues. Here, we report for the first time the polymeric particle preparation from HT as poly(Hematoxylin) ((p(HT)) microgels via microemulsion method in a one-step using a benign crosslinker, glycerol diglycidyl ether (GDE). P(HT) microgels are about 10 µm and spherical in shape with a zeta potential value of -34.6 ± 2.8 mV and an isoelectric point (IEP) of pH 1.79. Interestingly, fluorescence properties of HT molecules were retained upon microgel formation, e.g., the fluorescence emission intensity of p(HT) at 343 nm was about 2.8 times less than that of the HT molecule at λex: 300 nm. P(HT) microgels are hydrolytically degradable and can be controlled by using an amount of crosslinker, GDE, e.g., about 40%, 20%, and 10% of p(HT) microgels was degraded in 15 days in aqueous environments for the microgels prepared at 100, 200, and 300% mole ratios of GDE to HT, respectively. Interestingly, HT molecules at 1000 mg/mL showed 22.7 + 0.4% cell viability whereas the p(HT) microgels exhibited a cell viability of 94.3 + 7.2% against fibroblast cells. Furthermore, even at 2000 mg/mL concentrations of HT and p(HT), the inhibition% of α-glucosidase enzyme were measured as 93.2 ± 0.3 and 81.3 ± 6.3%, respectively at a 0.03 unit/mL enzyme concentration, establishing some potential application of p(HT) microgels for neurogenerative diseases. Moreover, p(HT) microgels showed two times higher MBC values than HT molecules, e.g., 5.0 versus 2.5 mg/mL MIC values against Gram-negative E. coli and Gram-positive S. aureus, respectively.

Effect of different proportions of glycerol and D-mannitol as plasticizer on the properties of extruded corn starch

In this study, thermoplastic starch (TPS) was prepared by melt extrusion process, in which glycerol and/or D-mannitol were used as plasticizers, and the effect of different glycerol/D-mannitol ratios (4:0, 3:1, 2:2, 1:3, and 0:4) on the physicochemical properties of the extruded starch samples was investigated. The short-range molecular order, crystallization, gelatinization, thermal stability, and thermal properties of the TPS samples were analyzed through attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray diffraction (XRD), rapid visco analysis (RVA), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The results showed that the crystallinity and short-range molecular order of the TPS samples increased with increasing glycerol content. Conversely, the water absorption index (WAI) and water solubility index (WSI) of the TPS samples decreased with increasing glycerol content. In addition, the TPS samples with higher glycerol content exhibited higher gel and thermal stabilities. This study provides a theoretical basis for starch extrusion and plasticization in the preparation of TPS-based materials with specific properties.

Preparation, characterization and release kinetics of a multilayer encapsulated Perilla frutescens L. essential oil hydrogel bead

Encapsulation has been widely used as the protection of essential oils, which gives the possibility of their implementation as food preservatives. In this study, Perilla frutescens L. essential oil (PLEO) microcapsule powders were prepared firstly by spray drying method using octenyl succinic anhydride starch (OSAs) as wall material, and then they were further encapsulated by sodium alginate and chitosan via polyelectrolyte complex coacervates method. The best results were obtained by using 4 % of OSAs-PLEO microcapsule powders, 2 % of sodium alginate and 1.5 % of chitosan producing PLEO hydrogel beads with encapsulation efficiency of 61.29 % and loading degree of 41.11 %. Morphology observation showed PLEO hydrogel beads was a millimeter scale spherical particle. FTIR assay confirmed the physical embedding of OSAs on PLEO and the formation of complex coacervates between sodium alginate and chitosan. TG and DSC assay showed the chitosan/alginate/OSAs complex coacervates as wall materials substantially improved the thermal stability of PLEO. Besides, PLEO hydrogel beads had a better stability in aqueous and acidic food formulations, which achieved a complete and prolonged release of PLEO. The Peppas-Sahlin model was the best approach for PLEO release profile, and release phenomenon was mainly governed by Fickian diffusion.

Mechanisms of lipid oxidation in water-in-oil emulsions and oxidomics-guided discovery of targeted protective approaches

Lipid oxidation is an inevitable event during the processing, storage, and even consumption of lipid-containing food, which may cause adverse effects on both food quality and human health. Water-in-oil (W/O) food emulsions contain a high content of lipids and small water droplets, which renders them vulnerable to lipid oxidation. The present review provides comprehensive insights into the lipid oxidation of W/O food emulsions. The key influential factors of lipid oxidation in W/O food emulsions are presented systematically. To better interpret the specific mechanisms of lipid oxidation in W/O food emulsions, a comprehensive detection method, oxidative lipidomics (oxidomics), is proposed to identify novel markers, which not only tracks the chemical molecules but also considers the changes in supramolecular properties, sensory properties, and nutritional value. The microstructure of emulsions, components from both phases, emulsifiers, pH, temperature, and light should be taken into account to identify specific oxidation markers. A correlation of these novel oxidation markers with the shelf life, the organoleptic properties, and the nutritional value of W/O food emulsions should be applied to develop targeted protective approaches for limiting lipid oxidation. Accordingly, the processing parameters, the application of antioxidants and emulsifiers, as well as packing and storage conditions can be optimized to develop W/O emulsions with improved oxidative stability. This review may help in emphasizing the future research priorities of investigating the mechanisms of lipid oxidation in W/O emulsion by oxidomics, leading to practical solutions for the food industry to prevent oxidative rancidity in W/O food emulsions.

Development, application and future trends of starch-based delivery systems for nutraceuticals: A review

As a natural biopolymer, starch is ideally adapted as an encapsulant material for nutraceutical delivery systems due to its unique nature of extensive sources, versatility and high biocompatibility. This review offers an outline of recent advances in the development of starch-based delivery systems. The structure and functional properties of starch in encapsulating and delivering bioactive ingredients are first introduced. Structural modification of starch improves the functionalities and extends the applications of starch in novel delivery systems. Then, various nutraceutical delivery systems are systematically summarized, which include porous starch, starch particle, amylose inclusion complex, cyclodextrin, gel, edible film and emulsion. Next, the delivery process of nutraceuticals is discussed in two parts: digestion and release. Intestinal digestion plays an important role during the whole digestion process of starch-based delivery systems. Moreover, controlled release of bioactives can be achieved by porous starch, starch-bioactive complexation and core-shell structure. Finally, the challenges of the existing starch-based delivery systems are deliberated, and the directions for future research are pointed out. Composite delivery carriers, co-delivery, intelligent delivery, delivery in real food systems, and reuse of agricultural wastes may be the research trends for starch-based delivery systems in the future.

Preparation and characterization of garlic polysaccharide-Zn (II) complexes and their bioactivities as a zinc supplement in Zn-deficient mice

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Garlic polysaccharide-Zn (II) complexes were prepared.

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The structural characterization confirmed the formation of complexes.

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The complexes could significantly improve the health of Zn-deficient mice.

This study explored the potential of garlic polysaccharides (GPs) as a carrier for synthesizing GP-Zn (II) complexes to supplement Zn. According to the response surface analysis, the optimal preparation conditions were: mass ratio of GPs to Zn²⁺ 1:0.21, temperature 53 °C, pH 5.9 and time 148.75 min, with the maximum chelation rate of 90.11%. The chelation of GPs and Zn²⁺ involved O—H/C—O/O—C—O groups, increased crystallinity and altered absorption peaks of circular dichroism spectra, with a higher thermal stability, particle size and negative zeta potential. Compared with inorganic zinc salts, supplementation of GP-Zn (II) complexes showed enhance zinc supplementation effects in Zn-deficient mice model: increased body weight, organ index and Zn (II) levels in serum and liver, enhanced Superoxidedismutase (SOD) activity and alkaline phosphatase activity, decreased NO content and Malondialdehyde (MDA) content and improved colon and testicular morphology. Therefore, GP-Zn (II) complex can be used as a potential zinc supplement for Zn-deficient individuals.

Preparation and characterization of vaccarin, hypaphorine and chitosan nanoparticles and their promoting effects on chronic wounds healing

Chronic wounds have become an important factor hindering human health, affecting tens of millions of people worldwide, especially diabetic wounds. Based on the antibacterial properties of chitosan, the angiogenesis promoting effect of vaccarin (VAC) and the anti-inflammatory effect of hypaphorine (HYP), nanoparticles with high bioavailability were prepared. VAC, HYP and chitosan nanoparticles (VAC + HYP-NPS) were used to the treatment of chronic wounds. Transmission electron microscopy (TEM) images showed the nanoparticles were spherical. ZetaPALS showed the potential of nanoparticles were -12.8 ± 5.53 mV and the size were 166.8 ± 29.95 nm. Methyl thiazolyl tetrazolium (MTT) assay showed that VAC + HYP-NPS had no toxicity and the biocompatibility was satisfactory. In the treatment of chronic wounds in diabetic rats, VAC + HYP-NPS significantly promoted the re-epithelialization of chronic wounds and accelerated the healing of chronic wounds. In the process of chronic wounds healing, VAC + HYP-NPS played the antibacterial effect of chitosan, the angiogenic effect of VAC and the anti-inflammatory effect of HYP, and finally promoted the chronic wounds healing. Overall, the developed VAC + HYP-NPS have potential application in chronic wounds healing. In view of the complexity of the causes of chronic wounds, multi-target drug administration may be an effective way to treat chronic wounds.

Food-Grade Microencapsulation Systems to Improve Protection of the Epigallocatechin Gallate

Epigallocatechin gallate (EGCG) is a catechin and one of the most abundant polyphenols in green tea, and it is under research for its potential benefit to human health and for its potential to be used in disease treatments, such as for cancer. However, the effectiveness of polyphenols depends on preserving their bioactivity, stability, and bioavailability. The EGCG was microencapsulated by a spray-drying process, using different biopolymers as encapsulating agents (gum arabic, modified chitosan and sodium alginate), in order to overcome some of the limitations of this compound. The microparticles showed a diameter around 4.22 to 41.55 µm (distribution in volume) and different morphologies and surfaces, depending on the encapsulating agent used. The EGCG release was total, and it was achieved in less than 21 min for all the formulations tested. The EGCG encapsulation efficiency ranged between 78.5 and 100.0%. The release profiles were simulated and evaluated using three kinetic models: Korsmeyer-Peppas (R²: 0.739-0.990), Weibull (R²: 0.963-0.994) and Baker-Lonsdale (R²: 0.746-0.993). The Weibull model was the model that better adjusted to the experimental EGCG release values. This study proves the success of the EGCG microencapsulation, using the spray-drying technique, opening the possibility to insert dried EGCG microparticles in different food and nutraceutical products.

Encapsulation of luteolin using oxidized lotus root starch nanoparticles prepared by anti-solvent precipitation

In this study, luteolin-oxidized lotus root starch (OLRS) nanoparticles (NPs) were developed to improve the stability and antioxidant activity of luteolin. Results showed that a stable luteolin-OLRS NPs was formed using luteolin and OLRS (oxidation degree, 15%) in the weight ratio of 3:1, as well as anti-solvent and solvent in the volume ratio of 10:1. Under this condition, the particle size, polydispersity index and zeta-potential of luteolin-OLRS NPs was 305 nm, 0.173 and -20.8 mV, respectively. The analysis of transmission electron microscopy, X-ray diffractometer and Fourier transform infrared spectroscopy demonstrated that the luteolin was successfully encapsulated in OLRS NPs, giving an encapsulation efficiency of 87.2%. The release characteristic and antioxidant activity of encapsulated luteolin were further investigated. Results exhibited that the OLRS NPs enabled luteolin to be stable in simulated gastric fluid and sustained release in simulated intestinal fluid, leading to the enhancement of antioxidant activity of luteolin.