Unveiling antioxidant capacity of standardized chitosan-tripolyphosphate microcapsules containing polyphenol-rich extract of Portulaca oleraceae.

The medicinal plant Portulaca oleraceae has a long history of usage in traditional medicine. Plant extracts have several interesting pharmacological effects but have some drawbacks that can be addressed via capsulation with chitosan. This work set out to do just that tally up the antioxidant effects of a polyphenol-rich P. olerace extract and see how capsulation affected them. The reflux extraction and response surface methodology (RSM) were carried out to optimize the phenolic and flavonoid content of P. oleraceae extract. Additionally, high-resolution mass spectrometry was employed to determine the secondary metabolite present in the extract. The microcapsules of extract-loaded chitosan were prepared using the ionic gelation method and characterized in terms of size, encapsulation efficiency (EE), and morphology of microcapsules. Fourier transform infrared (FTIR) was used to observe the successful production of microcapsules with a principal component analysis (PCA) approach. The antioxidant activity of microcapsules was established using the radical scavenging method. According to RSM, the highest amounts of TPC and TFC were obtained at 72.894 % ethanol, 2.031 h, and 57.384 °C. The compounds were employed from the optimized extract of P. oleraceae including phenolics and flavonoids. The microcapsules were secured with a %EE of 43.56 ± 2.31 %. The characteristics of microcapsules were approved for the obtained product's successful synthesis according to the PCA. The microcapsules have antioxidant activity in a concentration-dependent manner (p < 0.0001). The findings of this study underscored the benefits of employing chitosan as a nanocarrier for extract, offering a promising approach to enhance plant-derived therapies.

Encapsulation of pomegranate polyphenols by ionic gelation: Strategies for improved retention and controlled release.

This study aimed at producing pectin hydrogel beads by ionic gelation proce to carry pomegranate extract (PE) evaluating approaches to increase its retention and protect the polyphenols from environmental conditions that interfere in the stability and color of these compounds, such as the pH of the medium. Several strategies were tested to reduce the mass transfer and consequently increase its retention. The insertion of a filler (gelatinized starch), the employment of different concentrations from the external environment, the adsorption using blank pectin-starch beads, and the electrostatic coating using chitosan were performed. The release of entrapped compounds over time was employed to evaluate the release pattern of PE in water media. Diffusion coefficients calculated from these experiments were then used to estimate the PE release behavior. The encapsulation efficiency (EE) was significantly improved (42 % to 101 %) when equalizing the concentration of the external medium with that from the beads formulation. Furthermore, the increase in the PE concentration was proportional to the rise in the mechanical strength (MS) of the beads which indicates a modification of internal structure due to the presence of polyphenols. The adsorption was efficient in entrapping the active compound, and despite the high PE content observed for all beads (average value of 2960.26 mg of gallic acid equivalent/100 g sample), they had the lowest diffusion coefficient from the release in water media. Finally, the coating was able to reduce the release rate in most of the tests (DAB uncoated = 0.5 DAB coated), however, during the electrostatic deposition a loss of about 32 % of the phenolic compounds in the chitosan solution was observed which led to a reduced EE. Despite the obtention of retarded release, coating studies need to be improved. Some adjustments in the execution of this technique are necessary so that the losses are reduced and the process becomes viable for the use of beads in food.

In Vitro Bioaccessibility Assessment of Phenolic Compounds from Encapsulated Grape Pomace Extract by Ionic Gelation.

Grape pomace is a by-product of winemaking characterized by a rich chemical composition from which phenolics stand out. Phenolics are health-promoting agents, and their beneficial effects depend on their bioaccessibility, which is influenced by gastrointestinal digestion. The effect of encapsulating phenol-rich grape pomace extract (PRE) with sodium alginate (SA), a mixture of SA with gelatin (SA-GEL), and SA with chitosan (SA-CHIT) on the bioaccessibility index (BI) of phenolics during simulated digestion in vitro was studied. A total of 27 individual phenolic compounds (IPCs) were quantified by UHPLC. The addition of a second coating to SA improved the encapsulation efficiency (EE), and the highest EE was obtained for SA-CHIT microbeads (56.25%). Encapsulation affected the physicochemical properties (size, shape and texture, morphology, crystallinity) of the produced microbeads, which influenced the delivery of phenolics to the intestine and their BI. Thus, SA-GEL microbeads had the largest size parameters, as confirmed by scanning electron microscopy (SEM), and the highest BI for total phenolic compounds and IPCs (gallic acid, 3,4-dihydroxybenzoic acid and o-coumaric acid, epicatechin, and gallocatechin gallate) ranged from 96.20 to 1011.3%. The results suggest that encapsulated PRE has great potential to be used as a functional ingredient in products for oral administration.

An efficient method for improving the stability of Monascus pigments using ionic gelation.

BACKGROUND: Monascus pigments (Mps) are easily impacted by heating, pH and light, resulting in degradation. In this study, Mps were encapsulated by the ionic gelation method with sodium alginate (SA) and sodium caseinate (SC), as well as CaCl2 as a crosslinker. The encapsulated Mps SA/SC in four proportions (SA/SC: 1/4, 2/3, 3/2, 4/1, w/w). Then, the encapsulation efficiency and particle size of the SA/SC-Mps system were evaluated to obtain the optimal embedding conditions. Finally, the effects of heating, pH, light and storage on the stability of non-capsulated Mps and encapsulated Mps were assessed. RESULTS: SA/SC = 2/3 (AC2) had higher encapsulation efficiency (74.30%) of Mps and relatively small particle size (2.02 mm). The AC2 gel beads were chosen for further investigating the stability of encapsulated Mps to heating, pH, light and storage. Heat stability experiments showed that the degradation of Mps followed first-order kinetics, and the encapsulated Mps had lower degradation rates than non-capsulated Mps. Encapsulation could reduce the effect of pH on Mps. The effects of ultraviolet light on the stability of Mps were considered, and showed that the retention efficiency of encapsulated Mps was 22.01% higher than that of non-capsulated Mps on the seventh day. Finally, storage stability was also evaluated under dark refrigerated conditions for 30 days, and the results indicated that encapsulation could reduce the degradation of Mps. CONCLUSION: This study has proved that AC2 gel beads can improve the stability of Mps. Thus, the ionic gelation method is a promising encapsulation method to improve the stability of Mps. © 2023 Society of Chemical Industry.

Hybrid chitosan-lipid nanoparticles of green tea extract as natural anti-cellulite agent with superior in vivo potency: full synthesis and analysis.

The aim of this work is to exploit the advantages of chitosan (CS) as a nanocarrier for delivery of anti-cellulite drug, green tea extract (GTE), into subcutaneous adipose tissue. Primarily, analysis of herbal extract was conducted via newly developed and validated UPLC method. Ionic gelation method was adopted in the preparation of nanoparticles where the effect lecithin was investigated resulting in the formation of hybrid lipid-chitosan nanoparticles. Optimal formula showed a particle size of 292.6 ± 8.98 nm, polydispersity index of 0.253 ± 0.02, zeta potential of 41.03 ± 0.503 mV and an entrapment efficiency percent of 68.4 ± 1.88%. Successful interaction between CS, sodium tripolyphosphate (TPP) and lecithin was confirmed by Fourier-transform infrared spectroscopy, differential scanning calorimetry and X-ray diffraction. Morphological examination was done using transmission electron microscope and scanning electron microscope confirmed spherical uniform nature of GTE load CS-TPP nanoparticles. Ex vivo permeation study revealed permeability enhancing activity of the selected optimal formula due to higher GTE deposition in skin in comparison to GTE solution. Moreover in vivo study done on female albino Wistar rats carried out for 21 days proved successful potential anti-cellulite activity upon its application on rats' skin. Histological examination showed significant reduction of adipocyte perimeter and area and fat layer thickness. Results of the current study demonstrated that the developed GTE-loaded CS-TPP nanoparticle comprised of chitosan and lecithin showed permeability enhancing activity along with the proven lipolytic effect of green tea represent a promising delivery system for anti-cellulite activity.

Bioactive compounds in jamelão yogurt (Syzygium cumini L) / Compostos bioativos em iogurte de jamelão (Syzygium cumini L)

The jamelão fruit has been used in traditional Indian medicine and has recently attracted interest as a functional food, as it is rich in anthocyanins. Anthocyanins are of interest of the food industry due to their antioxidant power, attractive color and stability in acid-rich foods. This research used the gelation process with sodium alginate solution to obtain bioactive yogurt from the production of jamelão capsules added to natural yogurt. The proportion was 80% yogurt and 20% jellybean pulp capsules. The treatments were control yogurt (without the addition of jamelão capsules), jamelão capsules and bioactive yogurt (with the capsules). The objective was to study the antioxidant activity, physical-chemical, nutritional and microscopic stability of the product kept under refrigeration for 28 days at 4±1ºC. The addition of jamelão capsules in the yogurt changed the product's physical properties (increased humidity and decreased Brix and ash). There was an increase in the amount of phenols and anthocyanins, in addition to the antioxidant potential at 28 days of storage. The interior of the microcapsules was composed of a mesh structure through which the encapsulated material was distributed, as the capsules can be added to yogurt, to improve the antioxidant and nutritional capacity, which proves to be a promising and viable alternative.

A fruta Jamelão tem sido usada na medicina tradicional indiana e recentemente atrai interesse como alimento funcional, por ser rica em antocianinas. As antocianinas são de interesse da indústria de alimentos devido ao seu poder antioxidante, cor atraente e estabilidade em alimentos ácidos. Esta pesquisa utilizou o processo de gelificação com solução de alginato de sódio para obter iogurte bioativo, a partir da produção de cápsulas de jamelão adicionadas em iogurte natural. A proporção utilizada foi de 80% de iogurte e 20% de cápsulas de polpa de jamelão. Os tratamentos foram iogurte controle (sem adição de cápsulas de jamelão), cápsulas de jamelão e iogurte bioativo (contendo as cápsulas). O objetivo foi estudar a atividade antioxidante, a estabilidade físico-química, nutricional e microscópica do produto mantido sob refrigeração por 28 dias a 4 ± 1 ºC. A adição de cápsulas de jamelão no iogurte alterou as propriedades físicas do produto (aumento de umidade, diminuição de Brix e cinzas). Houve aumento na quantidade de fenóis e antocianinas, além do potencial antioxidante aos 28 dias de armazenamento. O interior das cápsulas era composto por uma estrutura em malha através da qual o material encapsulado foi distribuído. Desta forma, as cápsulas podem ser um ingrediente adicionado ao iogurte, melhorando a capacidade antioxidante e nutricional, provando ser uma alternativa promissora e viável.

Development, characterization and in vitro antioxidant activity of chitosan-coated alginate microcapsules entrapping Viola odorata Linn. extract.

Viola odorata Linn or sweet violet has several biological activities due to the presence of flavonoids, tannins, alaloid, glycoside, and saponins. However, susceptibility of these compounds to harsh conditions and low solubility is a great challenge for their incorporation into food products. Therefore, encapsulation can be an effective approach in this respect. In the present study, chitosan-coated microcapsules loaded with Viola extract were prepared for the first time and the effects of independent variables (sodium alginate: 1-1.5%, calcium chloride: 0.6-1.5% and extract concentrations: 5-10%) on encapsulation efficiency (EE%) were investigated. After evaluation of the model, the optimum condition for preparation of microcapsules was selected as 1.47% sodium alginate, 5.02% extract and 1.42% CaCl2 with EE% of 83.21%. The microcapsules developed at this condition had an acceptable spherical shape and the results obtained in Fourier transform-infrared spectroscopy (FTIR) indicated the presence of the extract within the microcapsules. The mean diameters of the uncoated and chitosan-coated microcapsules were 73 and 141 µm, respectively. The in vitro release in acidic medium (pH 1.5) and phosphate buffer saline (pH 7) were 43.21% and 95.39%, respectively. The prepared extract-loaded microcapsules have potential to be used in food products providing acceptable antioxidant activity.

Encapsulation of wheat germ oil in alginate-gelatinized corn starch beads: Physicochemical properties and tocopherols' stability.

Microencapsulation by production of polymer beads from ionic gelation is a useful method to improve the stability of nutritional compounds. Wheat germ oil is a nutritional source of unsaturated fatty acids and phytonutrients, such as tocopherols (α and ß), phytosterols, carotenoids, and phenolic compounds. This work studied the development of alginate-starch beads over the stability of encapsulated wheat germ oil. The beads contained sodium alginate and gelatinized corn starch in proportions of 2:0, 1:1, 1:2, and 1:4. The addition of small amounts (1:1) of gelatinized starch in the alginate emulsions improved the physicochemical properties and stability during storage. The emulsions had oil droplets with mean sizes ranging from 4.5 to 12.2 µm. The 1:1 samples showed more disperse oil droplets, explained by the molecular interaction between the starch chains and oil. The encapsulation efficiency was higher than 91%, and the beads' mean diameters were between 383.22 and 797.45 µm. The proportion of 1:1 alginate-starch also enhanced the beads' microstructures, avoiding oil oxidation. Six days accelerated stability (65 °C) evidenced higher tocopherols amounts (0.66 mg/g oil) and a lower oxidation (2.52 meq.O2 /kg oil) for the 1:1 samples compared to the remained samples. PRACTICAL APPLICATION: Alginate-gelatinized corn starch beads loaded with wheat germ oil can be used as an ingredient in functional food products for the enrichment of nutrients. The use of starch decreased the oil oxidation and the loss of tocopherols during storage, indicating that the quality of the wheat germ oil will be desirable for longer durations of food storage.

Pectin Hydrolysates from Different Cultivars of Pink/Red and White Grapefruits (Citrus Paradisi [macf.]) as Culture and Encapsulating Media for Lactobacillus Plantarum.

Citrus pectin hydrolysates (Citrus paradisi [Mafc.]) from "Foster," "Red Shambar," "Tangelo Orlando," and "Citrumelo Swingle" cultivars were obtained by partial chemical hydrolysis and their properties as culture media (sole carbon/nutrient source) and encapsulating agents of Lactobacillus plantarum CIDCA 83114 were evaluated. The concentration of neutral sugars was maximal after 2-hour hydrolysis. All hydrolysates were rich in glucose >xylose >galactose >galacturonic acid >mannose >arabinose. "Citrumelo Swingle" cultivar was the one with the highest concentration of xylose. After 24 hr of fermentation with L. plantarum CIDCA 83114, bacterial viability increased from 6.76 ± 0.14 to almost 9 log CFU/mL, and lactic acid concentration, from 2.63 ± 0.41 to 7.82 ± 0.15 mmol/L in all hydrolysates. Afterwards, bacteria were entrapped in pectate-calcium beads by ionotropic gelation. Bacterial viability did not significantly decrease after freeze-drying and storage the beads at 4 °C for 45 days. PRACTICAL APPLICATION: Pectin hydrolysates were adequate culture media for microorganisms, as determined by the viabililty and lactic acid production. Considering that citrus peels are agro-wastes obtained in large quantities, their use as encapsulating materials provides a solution to overcome the environmental problem they entail.

Release of anthocyanins from the hibiscus extract encapsulated by ionic gelation and application of microparticles in jelly candy.

Microparticles containing anthocyanin extract from Hibiscus sabdariffa L. (HE) were produced by the ionic gelation method by dripping-extrusion (D) and atomization (A). Double emulsion (HE/rapeseed oil/pectin) and a cross-linked solution (CaCl2) were used. The purpose of the study was to evaluate the release profile of anthocyanins under simulated gastrointestinal conditions, as well as microparticles application in pectin candy. Microparticles were incubated in simulated gastric and intestinal fluids and the release was evaluated by polyphenols, anthocyanin and color. Jelly candies were characterized and being tested for sensory acceptance (84 tasters). Samples were stored in the absence of light (25 °C/55% humidity) and evaluated for polyphenols, anthocyanin and color for 62-days. Microencapsulation of hibiscus anthocyanin resulted in improved enteric protection of bioactive compound, mainly in microparticles generated by dripping-extrusion. Application in jelly candy has shown to be technically feasible, with retention of up to 73% of bioactive compounds and mean sensorial acceptance of 70% tasters.

Encapsulation of stevia rebaudiana Bertoni aqueous crude extracts by ionic gelation - Effects of alginate blends and gelling solutions on the polyphenolic profile.

We formulated and characterised two alginate blends for the encapsulation of stevia extract (SE) via ionic gelation through an extrusion technique. Calcium chloride in SE and calcium chloride solutions were assessed as crosslinkers to overcome phenolic losses by diffusion and increase encapsulation efficiency (EE). Regardless of the blend, all stevia-loaded beads exhibited high EE (62.7-101.0%). The size of the beads decreased as EE increased. Fourier transform infrared analysis showed increased hydrogen bonding between SE and alginates, confirming the successful incorporation of SE within the matrix. Untargeted metabolomics profiling identified 479 free and encapsulated polyphenolic compounds. Flavonoids (catechin and luteolin equivalents) were predominant in SE whereas tyrosols and 5-pentadecylresorcinol equivalents were predominant in all bead formulations. Three-common discriminant compounds were exclusive to each blend and were inversely affected by the crosslinking conditions. Both alginate blends have been shown to be feasible as carrier systems of stevia extracts independent of crosslinking conditions.

Development and Characterization of Metformin Loaded Pectin Nanoparticles for T2 Diabetes Mellitus.

AIM: The present investigation was aimed to formulate and evaluate Metformin loaded pectin (PCM) nanoparticles (NPs) for sustained action for management of Type 2 Diabetes Mellitus (T2DM). METHOD: The nanoparticles were formulated by ionic gelation technique. The nano-formulations were subjected for the analyses of entrapment efficiency and drug release stud for 12h. The optimized formulation examined various in vitro characterizations such as particle size, zeta potential, surface morphology and FTIR studies. The in vitro heamocomptability, protein binding stability and glucose uptake studies were performed with nanoparticles. RESULTS: The PCMNP-4 showed drug entrapment efficiency, 68 ± 4.2 % and demonstrated favourable in vitro prolonged release characteristics. The mean particles diameter of optimized formulation was 482.7 nm and 0.270 poly dispersity index (PI), had spherical shape and zeta potential of (+38.85 mV). In addition, the nanoparticles were reasonably stable in the presence of excess bovine serum albumin, which suggested that the nanoparticles may also be stable in the blood stream. The percentage of haemolysis induced by Metformin and placebo PCNPs were less than 5%. The results indicated that the PCMNPs are hemocompatible and therefore, safe for oral administration. The glucose uptake was increased 1.5 fold in RBCs and L6 skeleton muscle cell line compared with Metformin. CONCLUSION: Hence, the designed nanoparticle system could possibly be advantageous in terms of prolonged release, to achieve reduced dose frequency and improve patient compliance.

Effects of microencapsulation by ionic gelation on the oxidative stability of flaxseed oil.

Flaxseed oil is a major source of omega-3 polyunsaturated fatty acids (PUFAs), as it contains nearly 50% of alpha-linolenic acid. For this reason it is highly susceptible to auto-oxidation. The aim of the work was to increase the stability of flaxseed oil by a microencapsulation process based on ionic gelation through vibrating-nozzle extrusion technology, using pectin as shell material. Two different drying systems, passive air drying (AD) and fluid bed (FB), were compared. The results show that the encapsulation efficiency is very high (up to 98%). Besides being approximately 20-fold faster, FB gives beads showing on average higher payload (76% vs 68%) and lower peroxide value (9.64 vs 21.33) than the AD. An accelerated test carried out on FB-dried beads shows that the oxidative stability of encapsulated oil is 13-fold higher than bulk oil (PV FB: 20 vs PV oil: 260), demonstrating the protecting effect of microencapsulation.

Development and characterization of iron-pectin beads as a novel system for iron delivery to intestinal cells.

Iron deficiency is the most common nutritional deficit worldwide. The goal of this work was to obtain iron-pectin beads by ionic gelation and evaluate their physiological behavior to support their potential application in the food industry. The beads were firstly analyzed by scanning electronic microscopy, and then physical-chemically characterized by performing swelling, thermogravimetric, porosimetry, Mössbauer spectroscopy and X-ray fluorescence analyses, as well as by determining the particle size. Then, physiological assays were carried out by exposing the beads to simulated gastric and intestinal environments, and determining the iron absorption and transepithelial transport into Caco-2/TC7 cells. Iron-pectin beads were spherical (diameter 1-2 mm), with high density (1.29 g/mL) and porosity (93.28%) at low pressure, indicating their high permeability even when exposed to low pressure. Swelling in simulated intestinal medium (pH 8) was higher than in simulated gastric medium. The source of iron [FeSO4 (control) or iron-pectin beads] did not have any significant effect on the mineral absorption. Regarding transport, the iron added to the apical pole of Caco-2/TC7 monolayers was recovered in the basal compartment, and this was proportional with the exposure time. After 4 h of incubation, the transport of iron arising from the beads was significantly higher than that of the iron from the control (FeSO4). For this reason, iron-pectin beads appear as an interesting system to overcome the low efficiency of iron transport, being a potential strategy to enrich food products with iron, without altering the sensory properties.

Structuring new alginate network aimed for delivery of dandelion (Taraxacum officinale L.) polyphenols using ionic gelation and new filler materials.

Alginate hydrogels are often used for immobilization of plant-derived bioactive compounds by fast and simple ionic gelation technique. However, the structure of alginate gel network is very porous and mostly result with high-diffusion rates of encapsulated compound, what limits its application as delivery vehicle. In order to prevent losses of bioactives and prepare efficient encapsulation systems, the aim of this study was to evaluate a potential of new natural fillers, cocoa powder (CP) and carob (C) for structuring alginate network aimed for encapsulation of aqueous dandelion (Taraxacum officinale L.) leaf extract using ionic gelation. Whey protein isolates served as a standard filler. The influence of different concentrations of gelling medium (2% and 3% calcium chloride) on encapsulation properties of alginate systems was also evaluated. Calcium concentration affected morphological properties (more acceptable when using 3% CaCl2), while textural properties and encapsulation efficiency of polyphenols and retained antioxidant capacity were more influenced by selected delivery materials. Alginate-whey protein isolates beads were scored with the highest loading capacity of polyphenols (>93%), while newly formulated binary mixtures (alginate-cocoa powder and alginate-carob) also enabled highly efficient entrapment of polyphenols (>88%). The slowest release of polyphenols in simulated gastrointestinal fluids were obtained when alginate was combined with CP and C, where system alginate-cocoa powder prepared with lower concentration of calcium chloride (2% CaCl2) enabled the most extended release of total polyphenols and hydroxycinnamic acids. Obtained results strongly justified implementation of new plant-derived functional fillers (cocoa powder and carob) for encapsulation purposes and opened new directions for designing of binary carrier's.

Nanoencapsulation of Red Ginseng Extracts Using Chitosan with Polyglutamic Acid or Fucoidan for Improving Antithrombotic Activities.

The potential of nanoencapsulation using bioactive coating materials for improving antithrombotic activities of red ginseng extract (RG) was examined. RG-loaded chitosan (CS) nanoparticles were prepared using antithrombotic materials, polyglutamic acid (PGA) or fucoidan (Fu). Both CS-PGA (P-NPs, 360 ± 67 nm) and CS-Fu nanoparticles (F-NPs, 440 ± 44 nm) showed sustained ginsenoside release in an acidic environment and improved ginsenoside solubility by approximately 122.8%. Both in vitro rabbit and ex vivo rat platelet aggregation of RG (22.3 and 41.5%) were significantly (p < 0.05) decreased within P-NPs (14.4 and 30.0%) and F-NPs (12.3 and 30.3%), respectively. Although RG exhibited no effect on in vivo carrageenan-induced mouse tail thrombosis, P-NPs and F-NPs demonstrated significant effects, likely the anticoagulation activity of PGA and Fu. Moreover, in the in vivo rat arteriovenous shunt model, P-NPs (156 ± 6.8 mg) and F-NPs (160 ± 3.2 mg) groups showed significantly lower thrombus formation than that of RG (190 ± 5.5 mg). Therefore, nanoencapsulation using CS, PGA, and Fu is a potential for improving the antithrombotic activity of RG.