Evaluation of microbial transglutaminase and ribose cross-linked soy protein isolate-based microcapsules containing fish oil

Vegetable proteins as encapsulating agents: Recent updates and future perspectives

The use of proteinaceous material is desired as it forms a protective gelation around the active core, making it safe through temperature, pH, and O₂ in the stomach and intestinal environment. During the boom of functional food utilization in this era of advancement in drug delivery systems, there is a dire need to find more protein sources that could be explored for the potential of being used as encapsulation materials, especially vegetable proteins. This review covers certain examples which need to be explored to form an encapsulation coating material, including soybeans (conglycinin and glycinin), peas (vicilin and convicilin), sunflower (helianthins and albumins), legumes (glutenins and albumins), and proteins from oats, rice, and wheat. This review covers recent interventions exploring the mentioned vegetable protein encapsulation and imminent projections in the shifting paradigm from conventional process to environmentally friendly green process technologies and the sensitivity of methods used for encapsulation. Vegetable proteins are easily biodegradable and so are the procedures of spray drying and coacervation, which have been discussed to prepare the desired encapsulated functional food. Coacervation processes are yet more promising in the case of particle size formation ranging from nano to several hundred microns. The present review emphasizes the significance of using vegetable proteins as capsule material, as well as the specificity of encapsulation methods in relation to vegetable protein sensitivity and the purpose of encapsulation accompanying recent interventions.

Interplay between transglutaminase treatment and changes in digestibility of dietary proteins

The changes in digestibility of TG-treated myofibrillar protein (MP), soybean protein isolate (SPI) and mixed proteins were evaluated by measuring liberation of primary amino groups, monitoring structural changes and investigating peptide fingerprints. TG treatment generally increased gastric digestion of treated proteins, possibly due to the structural changes occurred during TG treatment. In contrast, the initial intestinal digestion was suppressed by TG treatment. Compared with MP, the digestibility and peptide composition of SPI were affected by TG treatment to a larger degree, possibly due to the higher level of glutamine in SPI. Peptidomics analysis indicated that the changes in peptide composition of digests of TG-treated samples were related with the loss of Lys residues during TG treatment. Larger quantities of bioactive peptides KIEFEQFLPM, EVHEPEEKPRPK and TVKEDQVFPMNPPK were released after digestion of TG-treated MP. These results highlighted the complex and substantial influence of TG treatment on the digestibility of dietary proteins.

Improved stabilization of coix seed oil in a nanocage-coating framework based on gliadin-carboxymethyl chitosan-Ca2

Coix seed oil (CSO) is easily suffered functional-loss by oxidation and hydrothermal-treatment. The environmental stable nanocage-coating-CSO particles (OGC-Ca) by the frameworks consist of gliadins, carboxymethyl chitosan (CMCS) and Ca²⁺ were investigated. Results showed Ca²⁺ was the key controller for fabricating this nanocage-coating-frameworks, bridging macromolecule-chains with electrostatic interaction and hydrogen bonds, detected by FTIR, CD, DSC and XRD. SEM displayed new-formed velvet-like twigs after cross-linking CMCS to gliadins. Ca²⁺ assisted the nanocage-coating by significant down-sizing conversion OGC to OGC-Ca with consumption of twigs. OGC-Ca displayed a good stability towards heat (60-80 °C, 0-80 min), pH (3-8), NaCl (0-0.5 mM), storage (4/25 °C, 12 days), and a reduce of the pre-oxidation value of CSO in water and the improved controlled release of CSO in simulated GI tract. It illustrated GC-Ca frameworks would be a suitable delivery carrier for the CSO like pharmaceuticals and nutraceuticals for the food or medical use.

Advances of plant-based structured food delivery systems on the in vitro digestibility of bioactive compounds

Food researchers are currently showing a growing interest in in vitro digestibility studies due to their importance for obtaining food products with health benefits and ensuring a balanced nutrient intake. Various bioactive food compounds are sensitive to the digestion process, which results in a lower bioavailability in the gut. The main objective of structured food delivery systems is to promote the controlled release of these compounds at the desired time/place, in addition to protecting them during digestion processes. This review provides an overview of the influence of structured delivery systems on the in vitro digestive behavior. The main delivery systems are summarized, the pros and cons of different structures are outlined, and examples of several studies that optimized the use of these structured systems are provided. In addition, we have reviewed the use of plant-based systems, which have been of interest to food researchers and the food industry because of their health benefits, improved sustainability as well as being an alternative for vegetarian, vegan and consumers suffering from food allergies. In this context, the review provides new insights and comprehensive knowledge regarding the influence of plant-based structured systems on the digestibility of encapsulated compounds and proteins/polysaccharides used in the encapsulation process.

Legume proteins are smart carriers to encapsulate hydrophilic and hydrophobic bioactive compounds and probiotic bacteria: A review

Encapsulation is a promising technological process enabling the protection of bioactive compounds against harsh storage, processing, and gastrointestinal tract (GIT) conditions. Legume proteins (LPs) are unique carriers that can efficiently encapsulate these unstable and highly reactive ingredients. Stable LPs-based microcapsules loaded with active ingredients can thus develop to be embedded into processed functional foods. The recent advances in micro- and nanoencapsulation process of an extensive span of bioactive health-promoting probiotics and chemical compounds such as marine and plant fatty acid-rich oils, carotenoid pigments, vitamins, flavors, essential oils, phenolic and anthocyanin-rich extracts, iron, and phytase by LPs as single wall materials were highlighted. A technical summary of the use of single LP-based carriers in designing innovative delivery systems for natural bioactive molecules and probiotics was made. The encapsulation mechanisms, encapsulation efficiency, physicochemical and thermal stability, as well as the release and absorption behavior of bioactives were comprehensively discussed. Protein isolates and concentrates of soy and pea were the most common LPs to encapsulate nutraceuticals and probiotics. The microencapsulation of probiotics using LPs improved bacteria survivability, storage stability, and tolerance in the in vitro GIT conditions. Moreover, homogenization and high-pressure pretreatments as well as enzymatic cross-linking of LPs significantly modify their structure and functionality to better encapsulate the bioactive core materials. LPs can be attractive delivery devices for the controlled release and increased bioaccessibility of the main food-grade bioactives.

Review on plant protein-polysaccharide complex coacervation, and the functionality and applicability of formed complexes

Controlling the interactions between plant proteins and polysaccharides can lead to the development of novel electrostatic complexed structures that can give unique functionality. This in turn can broaden the diversity of applications that they may be suitable for. Overwhelmingly in the literature, work and reviews relating to coacervation have involved the use of animal proteins. However, with the increasing demand for plant-based protein alternatives by industry and consumers, a greater understanding of how they interact with polysaccharides is essential to control structure, functionality and applicability. This review discusses the factors governing the nature of protein-polysaccharide interactions, their functional attributes and industrial applications, with special attention given to plant proteins. © 2018 Society of Chemical Industry.

Sericin/RBA embedded gellan gum based smart nanosystem for pH responsive drug delivery

Polysaccharides protein complex offers a green alternative to synthetic polymers in the drug delivery system. Sericin (SC), a natural protein, in combination with rice bran albumin (RBA) and gellan gum (GG) forms a green based protein polysaccharide complex. The sericin functionalized gellan gum-rice bran (SC-GG-RBA) nanocomposites were characterized by different characterization techniques. It shows their prominent ability in balancing the biocompatibility, stability, biodegradability, and functionality of nanocarriers. The nanocomposites exhibited spherical shape with core protein-polysaccharide structures, and the average size was about 218 nm. High amount of Doxorubicin (DOX) was encapsulated into SC-GG-RBA nanocomposites in order to investigate the effective drug release in acidic tumor environment. DOX of 84% was released in vitro condition after 120 h in pH 4.0. DOX loaded green nanocomposites shows IC₅₀ 5 μg/mL which was very low compared to free DOX of 9 μg/mL after treatment with MCF-7 cells. Only 42% of cells were survived after treatment with green nanocomposites. This was due to the effective uptake of nanomaterial by cancer cells and direct release of DOX in cytoplasmic region. Such high performance green nanocomposites have great potential in expanding the utilization of biomaterial from natural resources and development of sensible application in biomedical field.

Complex coacervation in charge complementary biopolymers: Electrostatic versus surface patch binding

In this review, a number of systems are described to demonstrate the effect of polyelectrolyte chain stiffness (persistence length) on the coacervation phenomena, after we briefly review the field. We consider two specific types of complexation/coacervation: in the first type, DNA is used as a fixed substrate binding to flexible polyions such as gelatin A, bovine serum albumin and chitosan (large persistence length polyelectrolyte binding to low persistence length biopolymer), and in the second case, different substrates such as gelatin A, bovine serum albumin, and chitosan were made to bind to a polyion gelatin B (low persistence length substrate binding to comparable persistence length polyion). Polyelectrolyte chain flexibility was found to have remarkable effect on the polyelectrolyte-protein complex coacervation. The competitive interplay of electrostatic versus surface patch binding (SPB) leading to associative interaction followed by complex coacervation between these biopolymers is elucidated. We modelled the SPB interaction in terms of linear combination of attractive and repulsive Coulombic forces with respect to the solution ionic strength. The aforesaid interactions were established via a universal phase diagram, considering the persistence length of polyion as the sole independent variable.

Soy protein/soy polysaccharide complex nanogels: folic acid loading, protection, and controlled delivery

In this study, we developed a facile approach to produce nanogels via self-assembly of folic acid, soy protein, and soy polysaccharide. High-pressure homogenization was introduced to break down the original aggregates of soy protein, which benefits the binding of soy protein with soy polysaccharide and folic acid at pH 4.0. After a heat treatment that causes the soy protein denaturation and gelation, folic acid-loaded soy protein/soy polysaccharide complex nanogels were fabricated. The nanogels have a polysaccharide surface that makes the nanogels dispersible in acidic conditions where folic acid is insoluble and soy protein forms precipitates after heating. More importantly, the protein and polysaccharide can inhibit the reactions between dissolved oxygen and folic acid during UV irradiation. After the preparation and storage of the nanogels in the presence of heat, oxygen, and light in acidic conditions, most of the folic acid molecules in the nanogels remain in their natural structure and can be released rapidly at neutral pH, that is, in the intestine. Because most food and beverages are acidic, the nanogels are a suitable delivery system of folic acid in food and beverages.

In vitro study of the release properties of soy-zein protein microspheres with a dynamic artificial digestive system

The purpose of this work was to study the performance of microspheres of soy protein isolate (SPI), zein, or SPI-zein complex as vehicles of nutraceutical delivery under fasting and prandial conditions in an artificial digestive system (TIM-1). Riboflavin availability for absorption from the small intestine compartments reached 90% of the total load within 4 h, most of it (65-80%) turning up in the jejunum dialysis fluid, suggesting that this segment is the main site of absorption, regardless of the nature of the microspheres. However, the riboflavin concentrations and the availability for absorption profiles depended on microsphere formulation. Release from pure SPI and zein microspheres in the stomach compartment occurred within 15 min. The availability for absorption from both the jejunum and ileum compartment followed first-order kinetics, indicating that the limiting step in nutrient uptake with these two formulations is absorption by passive diffusion. SPI-zein complex microspheres provided sustained release of riboflavin over 4 h and a near-zero-order nutrient availability for absorption profile in both fasting and prandial states. Suspending SPI-zein complex microspheres in yogurt significantly delayed nutrient release, which would increase the likelihood of gastric-sensitive nutrients passing intact into the intestine for absorption. SPI-zein complex microspheres thus show potential for use as nutraceutical delivery vehicles in the creation of novel functional foods.

Elaboration and characterization of soy/zein protein microspheres for controlled nutraceutical delivery

Microspheres (15-25 microm) of soy protein isolate (SPI), zein, and SPI/zein blends were prepared using a cold gelation method as possible delivery systems for nutraceutical products. Microsphere matrix crystalline structure, swelling behavior, and nutrient load release kinetics in simulated gastrointestinal fluids were investigated. SPI microspheres showed early burst release of the model nutrient, whereas zein microspheres showed very slow release in both simulated gastric and intestinal fluids. Blending of SPI and zein provides a convenient method of adjusting the hydrophobicity and crystallinity of the protein matrix and hence its swelling behavior and in vivo nutrient release kinetics. Diffusion plays a major role in regulating nutrient release. SPI/zein microspheres blended at ratios of 5:5 and 3:7 showed near zero-order release kinetics over the test period in simulated intestinal buffer and thus have potential as delivery vehicles for nutraceutical products in functional foods.