Encapsulation Of Bioactive Compounds Research Articles

Improved encapsulation efficiency and storage stability of lutein by soy protein isolate nanocarriers with thermal and trypsin treatments.

Encapsulation of bioactive compounds within protein-based nanoparticles has garnered considerable attention in the food and pharmaceutical industries because of its potential to enhance stability and delivery. Soy protein isolate (SPI) has emerged as a promising candidate, prompting the present study aiming to modify its properties through controlled thermal and trypsin treatments for improved encapsulation efficiency (EE) of lutein and its storage stability. The EE of lutein nanoparticles encapsulated using SPI trypsin hydrolysates (SPIT) with three varying degrees of hydrolysis (4.11%, 6.91% and 10.61% for SPIT1, SPIT2 and SPIT3, respectively) increased by 12.00%, 15.78% and 18.59%, respectively, compared to SPI. Additionally, the photostability of SPIT2 showed a remarkable increase of 38.21% compared to SPI. The superior encapsulation efficiency and photostability of SPIT2 was attributed to increased exposure of hydrophobic groups, excellent antioxidant activity and uniform particle stability, despite exhibiting lower binding affinity to lutein compared to SPI. Furthermore, in SPIT2, the protein structure unfolded, with minimal impact on overall secondary structure upon lutein addition. The precise application of controlled thermal and trypsin treatments to SPI has been shown to effectively produce protein nanoparticles with substantially improved encapsulation efficiency for lutein and enhanced storage stability of the encapsulated lutein. These findings underscore the potential of controlled thermal and trypsin treatments to modify protein properties effectively and offer significant opportunities for expanding the applications of protein-based formulations across diverse fields. © 2024 Society of Chemical Industry.

Layer-by-Layer Assembling and Capsule Formation of Polysaccharide-Based Polyelectrolytes Studied by Whispering Gallery Mode Experiments and Confocal Laser Scanning Microscopy

The layer-by-layer (LbL) assembling of oppositely charged polyelectrolytes was studied using semi-synthetic polysaccharide derivatives, namely the polycations 6-aminoethylamino-6-deoxy cellulose (ADC) and cellulose (2-(ethylamino)ethylcarbamate (CAEC), as well as the polyanion cellulose sulfate (CS). The synthetic polymers poly(allylamine) (PAH) and poly(styrene sulfonate) (PSS) were employed as well for comparison. The stepwise adsorption process was monitored by whispering gallery mode (WGM) experiments and zeta-potential measurements. Distinct differences between synthetic- and polysaccharide-based assemblies were observed in terms of the quantitative adsorption of mass and adsorption kinetics. The LbL-approach was used to prepare µm-sized capsules with the aid of porous and non-porous silica particle templates. The polysaccharide-based capsule showed a switchable permeability that was not observed for the synthetic polymer materials. At ambient pH values of 7, low-molecular dyes could penetrate the capsule wall while no permeation occurred at elevated pH values of 8. Finally, the preparation of protein-loaded LbL-capsules was studied using the combination of CAEC and CS. It was shown that high amounts of protein (streptavidin and ovomucoid) can be encapsulated and that no leaking or disintegration of the cargo macromolecules occurred during the preparation step. Based on this work, potential use in biomedical areas can be concluded, such as the encapsulation of bioactive compounds (e.g., pharmaceutical compounds, antibodies) for drug delivery or sensing purposes.

Application of functional compounds from agro-industrial residues of Brazilian's tropical fruits extracted by sustainable methods in alginate-chitosan microparticles

The extraction and encapsulation of bioactive compounds have emerged as promising strategies to enhance their utility in various industrial applications. This study explores functional compounds derived from tropical fruit waste, including grape pomace, jabuticaba, and dragon fruit. These compounds were extracted using sustainable methods such as ultrasound-assisted extraction, maceration, and pressurized liquid extraction for incorporation into alginate and chitosan microparticles. Among the extraction methods employed, pressurized liquid extraction demonstrated the highest efficiency in recovering phenolic compounds, anthocyanins, and betalains. The optimized microparticles were tailored to specific fruit sources, with chitosan concentrations of 0.19%, 0.27%, and 0.34%, and alginate concentrations of 2.26%, 1.79%, and 1.73% for grape pomace, dragon fruit husk, and jabuticaba peel, respectively. These microparticles exhibited encapsulation efficiencies ranging from 98.43% to 99.78%. Furthermore, they displayed low solubility (0.23%–0.39%) and high hygroscopicity (38.92%–41.01%). In vitro gastrointestinal digestibility tests showed that the bioaccessibility of the phenolic compounds reached up to 95%. This finding suggests that the encapsulated bioactive compounds remain highly bioavailable, making them potentially valuable in the development of pharmaceutical and health products as well as functional foods. In conclusion, this research underscores the significance of valorizing tropical fruit by-products in Brazil through pressurized liquid extraction, followed by their efficient encapsulation within alginate and chitosan matrices. This process not only reduces waste but also opens up exciting avenues for applications in the food and pharmaceutical sectors.

Fabrication of fast-dissolving electrospun polyvinyl alcohol/pea protein isolate nanofibers for enhancing solubility of Lion’s Mane mushroom extract

This research aimed to produce “fast-dissolving nanofibers” from polyvinyl alcohol (PVA) and pea protein isolate (PPI) by electrospinning using a green approach. Lion’s Mane (LM) mushroom extract was added to the optimized PVA/PPI solution (PVA:PPI 50:50 by weight ratio added with 1 % v/v Tween20) to increase solubility of LM extract. LM extract can be encapsulated within PVA/PPI nanofibers and fast-dissolved in a phosphate solution. Results exhibited high potential use of electrospinning for encapsulation of bioactive compounds through fast-dissolving nanofiber forms.

Effect of the Structural Modification of Plant Proteins as Microencapsulating Agents of Bioactive Compounds from Annatto Seeds (Bixa orellana L.).

This project studied the use of lentil protein (LP) and quinoa protein (QP) in their native and modified states as carrier material in the encapsulation process by the ionic gelation technique of annatto seed extract. Soy protein (SP) was used as a model of carrier material and encapsulated bioactive compounds, respectively. The plant proteins were modified by enzymatic hydrolysis, N acylation, and N-cationization to improve their encapsulating properties. Additionally, the secondary structure, differential scanning calorimetry (DSC), solubility as a function of pH, isoelectric point (pI), molecular weight (MW), the content of free thiol groups (SH), the absorption capacity of water (WHC) and fat (FAC), emulsifier activity (EAI), emulsifier stability (ESI), and gelation temperature (Tg) were assessed on proteins in native and modified states. The results obtained demonstrated that in a native state, LP (80.52% and 63.82%) showed higher encapsulation efficiency than QP (73.63% and 45.77%), both for the hydrophilic dye and for the annatto extract. Structural modifications on proteins improve some functional properties, such as solubility, WHC, FAC, EAI, and ESI. However, enzymatic hydrolysis on the proteins decreased the gels' formation, the annatto extract's encapsulated efficiency, and the hydrophilic dye by the ionic gelation method. On the other hand, the modifications of N-acylation and N-cationization increased but did not generate statistically significant differences (p-value > 0.05) in the encapsulation efficiency of both the annatto extract and the hydrophilic dye compared to those obtained with native proteins. This research contributes to understanding how plant proteins (LP and QP) can be modified to enhance their encapsulating and solubility properties. The better encapsulation of bioactive compounds (like annatto extract) can improve product self-life, potentially benefiting the development of functional ingredients for the food industry.

Palm-based nanofibrillated cellulose (NFC) in carotenoid encapsulation and its incorporation into margarine-like reduced fat spread as fat replacer.

Nanofibrillated cellulose (NFC) from plant biomass is becoming popular, attributed to the protective encapsulation of bioactive compounds in Pickering emulsion, preventing degradation and stabilizing the emulsion. NFC, as a natural dietary fiber, is a prominent fat replacer, providing a quality enhancement to reduced-fat products. In this study, NFC Pickering emulsions were prepared at NFC concentrations of 0.2%, 0.4%, 0.6%, 0.8%, and 1% to encapsulate carotenoids. The NFC Pickering emulsions at NFC concentrations of 0.4%, 0.6%, 0.8%, and 1% were incorporated into margarine-like reduced fat (3%) spreads as the aqueous phase. Characterization of both NFC Pickering emulsion and the incorporated NFC Pickering emulsion, margarine-like reduced fat spreads, was conducted with mastersizer, rheometer, spectrophotometer, and texture analyzer. The particle size (73.67±0.35 to 94.73±2.21nm), viscosity (138.36±3.35 to 10545.00±567.10mPas), and creaming stability (25% to 100% stable) of the NFC Pickering emulsions were increased significantly when increasing the NFC concentration, whereas the encapsulation efficiency was highest at NFC 0.4% and 0.6%. Although imitating the viscoelastic solid-like behavior of margarine was difficult, the NFC Pickering emulsion properties were still able to enhance hardness, slip melting point, and color of the reduced fat spreads compared to the full-fat margarine, especially at 0.6% of NFC. Overall, extensive performances of NFC can be seen in encapsulating carotenoids, especially at NFC concentrations of 0.4% and 0.6%, with the enhancement of Pickering emulsion stability while portraying futuristic possibilities as a fat replacer in margarine optimally at 0.6% of NFC concentration. PRACTICAL APPLICATION: Nanocellulose extracted from palm dried long fiber was utilized to encapsulate carotenoids and replace fats in margarine-like reduced fat (3%) spreads. Our study portrayed high encapsulation efficiency and successful fat replacement with promising stability performances. Hence, nanocellulose displayed extensive potential as encapsulating agents and fat replacers while providing quality and sustainability enhancements in reduced-fat food.

Microencapsulation of Hibiscus sabdariffa L. extract using porous starch and gum Arabic: Optimized process, characterization, stability, and simulated gastrointestinal conditions

Hibiscus extract exhibits considerable antioxidant activity and a high anthocyanin content, which suggesting potential health benefits. However, these compounds are highly susceptible to environmental factors. The aim of this study was to establish the optimal conditions for the encapsulation of Hibiscus sabdariffa extract (HSE) using mixed porous maize starch–gum Arabic to enhance the stability of bioactive compounds under accelerated aging conditions. Response surface methodology (RSM) was used to optimize microencapsulation conditions through spray drying. The optimal conditions for microencapsulation of HSE by RSM were determined to be 126 °C at the inlet temperature (IT) and 8.5 % at the total solid content (TSC). Using these conditions, the amount of bioactive compounds in optimized microcapsules (OMs) was 2368 mg GAE/100 g, 694 mg QE/100 g, and 930 mg EC3G/100 g, of phenolic compounds, flavonoids, and anthocyanin, respectively. The release rate of anthocyanins during in vitro digestion was more effectively regulated in the OM sample, which retained up to 40 % of anthocyanins compared with 10 % in the HSE. The experimental values in this study exhibit high assertiveness, which renders the optimization model technologically and financially viable for the encapsulation of bioactive compounds with potential use in the food and pharmaceutical industries.

Encapsulation of zingerone by self-assembling peptides derived from fish viscera: Characterization, interaction and effects on colon epithelial cells

The purpose of the present work was to encapsulate zingerone (a bioactive compound from ginger) by self-assembling peptides derived from fish viscera. The encapsulation conditions were investigated and the structure of fish peptides-zingerone complex was characterized. The interaction between zingerone and fish peptides was investigated using fluorescence spectroscopy. Further research was performed on the in vitro release of zingerone and fish peptide-zingerone as well as their antiproliferative effects on colon epithelial Caco-2 cells. The results demonstrated that zingerone can be successfully encapsulated by self-assembling peptides derived from fish viscera with high encapsulation efficiency and loading capacity. Furthermore, transmission electron microscope and confocal laser scanning microscope observations revealed the successful encapsulation of zingerone by fish viscera peptides. In addition, in vitro release and antiproliferative activity against Caco-2 cells can be significantly increased by encapsulating zingerone via peptide self-assembly. The current study advances knowledge of encapsulation of bioactive compounds through peptide self-assembly.

Ultrasound-Assisted Maillard Conjugation of Yeast Protein Hydrolysate with Polysaccharides for Encapsulating the Anthocyanins from Aronia.

Valorisation of food by-products, like spent brewer's yeast and fruit pomaces, represents an important strategy for contributing to sustainable food production. The aims of this study were to obtain Maillard conjugates based on spent yeast protein hydrolysate (SYH) with dextran (D) or maltodextrin (MD) by means of ultrasound treatment and to use them for developing encapsulation systems for the anthocyanins from aronia pomace. The ultrasound-assisted Maillard conjugation promoted the increase of antioxidant activity by about 50% compared to conventional heating and SYH, and was not dependent on the polysaccharide type. The ability of the conjugates to act as wall material for encapsulating various biologically active compounds was tested via a freeze-drying method. The retention efficiency ranged between 58.25 ± 0.38%-65.25 ± 2.21%, while encapsulation efficiency varied from 67.09 ± 2.26% to 88.72 ± 0.33%, indicating the strong effect of the carrier material used for encapsulation. The addition of the hydrolysed yeast cell wall played a positive effect on the encapsulation efficiency of anthocyanins when used in combination with the SYH:MD conjugates. On the other hand, the stability of anthocyanins during storage, as well as their bioavailability during gastrointestinal digestion, were higher when using the SYH:D conjugate. The study showed that hydrolysis combined with the ultrasound-assisted Maillard reaction has a great potential for the valorisation of spent brewer's yeast as delivery material for the encapsulation of bioactive compounds.

Effect of incorporating modified pinhão starch in alginate-based hydrogel beads for encapsulation of bioactive compounds by hydrodynamic electrospray ionization jetting

Known for its antioxidant properties, Araucaria angustifolia bracts extract was encapsulated using hydrodynamic electrospray ionization jetting within calcium alginate cross-linked hydrogel beads with varying contents of modified pinhão starch. The rheological properties of the dispersions and analysis of the physicochemical and digestive properties of encapsulated beads were studied. The results demonstrated that dispersions containing starch exhibited higher viscosity and reduced compliance values, indicating samples with stronger, more compact, and stable structures that are less susceptible to deformation. This was confirmed by the beads rupture strength test. The ATR-FTIR analysis suggest that no new chemical bonds were formed, with encapsulation being responsible only for physical interactions between the functional groups of the polymers used and the active groups of the compounds present in the extract. The thermal stability of starch-containing beads was higher. Total tannins were higher in beads containing starch, with 53.61 %, 56.83 %, and 66.99 % encapsulation yield for samples with 2 %, 4 %, and 6 % starch, respectively, and the remaining antioxidant activity ranged from 96.04 % to 81.08 %. In vitro gastrointestinal digestion simulation indicated that the highest releases occurred in the intestinal phase, ranging from 60.72 % to 63.50 % for the release of total phenolic compounds.

Optimizing encapsulation of black carrot extract using complex coacervation technique: Maximizing the bioaccessibility and release kinetics in different food matrixes

The encapsulation of bioactive compounds at the micro-scale presents an advanced approach for the food and nutraceutical industries. However, the challenge lies in determining optimal encapsulation parameters for each specific bioactive compound and encapsulation method. In addressing this, our study demonstrates the application of statistical programs to streamline the optimization of wet-lab experimental designs. Focusing on the encapsulation technique of complex coacervates for black carrot phenolic extract (BCPE), the response surface methodology was employed to optimize encapsulation parameters in terms of coating material, the core-to-coating material ratio, and the pH of the encapsulation environment. The optimum conditions predicted by RSM to produce BCPE-loaded complex coacervates were found to be a pH of 3.02, a core-to-coating ratio of 10g/100g, and a coating material composition of 59.10g/100 mL maltodextrin, and 0.90g/100 mL whey protein isolate. According to the RSM pattern with 84% desirability, encapsulation efficiency was found 86.08%. In addition, the effect of different food matrixes was examined on the in vitro bioaccessibility of spray-dried BCPE loaded complex coacervated powder (BCPE-CCp). To explore the impact of protein and carbohydrate richness, along with food temperature on capsule stability, the BCPE-CCp was incorporated into skim milk, apple juice, and chocolate beverages (1g/100 mL). Notably, heat treatment had no significant effect on the in vitro bioaccessibility of BCPE-CCp in terms of total phenolic compound and antioxidant activity (p < 0.05), indicating its suitability for hot formulations. Furthermore, the release of BCPE in a protein-rich environment was observed to be higher than in a carbohydrate-rich food matrix under both gastric and intestinal conditions. These findings provide valuable insights into the stability and release dynamics of BCPE-CCp in different food settings, supporting its adaptability for diverse formulations, including those involving elevated temperatures.

Encapsulation of bioactive compounds extracted from haritaki pulp (Terminalia chebula Retzius): characterization of physical, thermal, and morphological properties

The bioactive compounds of haritaki (Terminalia chebula Retzius) were microencapsulated using zein and starch as the encapsulating agents, utilizing both conventional (encapsulator) and advanced (freeze drying) techniques.

Effect of different hydrocolloids on Ca (II) – alginate beads containing extracts from Arthrospira platensi

Alginate was applied in food matrix, and pharmaceutical products for efficient encapsulation of bioactive compounds or as a drug carrier. In the current study phycocyanin isolated from dry Arthrospira platensis/Spirulina was encapsulated in alginate beads. The aim of the current research was to evaluate the effect of different hydrocolloids (inulin, pectin and guar) at different pH values and temperatures on phycocyanin content in the alginate beads. The alginate microspheres were formed with 1% sodium alginate, 6% sucrose, 1% phycocyanin, and selected hydrocolloids, as neutral polysaccharides (inulin and guar) and anionic heteropolysaccharides (pectin). Moreover, the diameter of alginatephycocyanin beads with or without hydrocolloids was evaluated. The addition of sucrose and inulin in a concentration of 6 % to alginate-phycocyanin beads stored at 25 and 37 °C showed the highest content of phycocyanin. The phycocyanin loss was minor at pH 6 and pH 9, respectively, especially when 0.8% pectin or 6% inulin was added to the alginate matrix. XRD patterns of all beads showed amorphous humps situated at different angles, depending on the particulate type of the hydrocolloid. The current research evaluates the potential of alginate beads with phycocyanin, as well as with pectin, guar and inulin to be used in food and pharmaceutical products.

Encapsulation of Bioactive Compounds from Germinated Mung Bean by Freeze-Drying, Release Kinetics, and Storage Stability.

This research explores the application of germinated mung bean extract, rich in GABA (Gamma-aminobutyric acid) and polyphenols, in enhancing human health. Recognizing the instability of these bioactive compounds in environmental conditions, encapsulation emerges as a pivotal technique to broaden their applications in food and pharmaceuticals. Utilizing response surface methodology and Box-Behnken design, the freeze-drying formulation for encapsulating the aqueous extract was optimized. Second-order polynomial models were developed, exhibiting statistical adequacy in predicting key variables such as encapsulation efficiency for GABA (EE-GABA) and total polyphenol content (EE-TPC), as well as encapsulation yield for GABA (EY-GABA) and total polyphenol content (EY-TPC). The established optimal formulation was validated, resulting in predicted values for EE-GABA, EE-TPC, EY-GABA, and EY-TPC. The release kinetics of encapsulated particles were investigated, highlighting the suitability of the Korsmeyer-Peppas and Higuchi models. Assessing the stability of the encapsulated powder under varying temperatures and humidities revealed degradation rates, half-life, and activation energy, with moisture equilibrium established at 4.70%, indicative of long-term stability. In conclusion, the encapsulated germinated mung bean powder demonstrates high stability, making it a promising candidate for integration into food products and functional ingredients.

“Electromillifluidic” encapsulation of cinnamon oil: Characterization and in-vitro digestion assessment

Electromillifluidic is introduced as a novel encapsulation technique to fabricate small core-shell millicapsules filled with cinnamon oil with high productivity. The effect of the flow rate ratios of dispersed and continuous phases and applied voltage on encapsulation efficiency, loading capacity, size, and sphericity of millicapsules were analyzed. Reynolds number confirmed a Laminar flow in the glass tube (0.028). The small Capillary value (0.095), electric Capillary numbers (0.024–0.054) of the continuous phase, and also Weber number of the dispersed phase (4.7 × 10−4–15.3 × 10−4) showed a dripping flow regime. Enhancing the voltage reduced the size and sphericity; however, the Young Modulus was improved. The maximum release of oil (97.19%) from chitosan-coated millicapsules in the gastrointestinal tract and its lowest leakage (73.43%) were observed at 18 and 0 kV, respectively. The results confirm the potential of this technique for the encapsulation of bioactive compounds in the food and pharmaceutical industry.

Effect of Chemical Degradation of Sodium Alginate on Capsaicin Encapsulation

Capsaicin is known as an oily extract of paprika that is characterized by pungent taste and bioactivity. It also may cause irritation to the mouth and stomach which is why is so important to immobilize capsaicin on a carrier to prevent it. The usage of alginate oligomers, which has an antioxidant potential compared to alginate, is of benefit because it may be used in the immobilization of bioactive substances that are fragile to oxidation. The purpose of this study was to use sodium alginate oligomers as a coating material in the encapsulation process of paprika oleoresin. Alginate oligomers were produced by chemical degradation with hydrogen peroxide. The characteristics of the samples were obtained by measuring the viscosity, the contact angle of the surface, and the surface tension of solutions. The obtained solution of alginate oligomers served as the carrier material for the immobilization of capsaicin. Capsules were prepared by ionic gelation using a calcium chloride solution as a crosslinking agent. In this way, capsules without and with the core (capsaicin) were prepared and their ability to scavenge free radicals (DPPH) and iron-reducing properties (FRAP) were determined. The stability of the capsules was examined by thermal decomposition and under conditions of the gastric and small intestine, and capsaicin content was detected using high-performance liquid chromatography. It was found that alginate oligomers could be used in the encapsulation of bioactive compounds and the efficiency was above 80%. Capsule production from alginate oligomers affected their thermal stability. The use of alginate derivatives as a carrier increased the antioxidant properties of the finished product, as well as its ability to reduce iron ions. The use of alginate oligomers as a coating material prevented the active substance from being released too early in the conditions of the small intestine, prolonged the stability of the capsules, and supported their durability in gastric conditions.

Use of Ora-pro-nóbis (Pereskia aculeata Miller) mucilage as a wall material in microencapsulation by complex coacervation

Innovative materials for the encapsulation of bioactive compounds are a permanent challenge. In this sense, the purpose of the study was to evaluate the use of Ora-pro-nobis mucilage (MOPN) as a wall material to replace Arabic gum (AG), in microencapsulation by complex coacervation of bocaiuva (Acrocomia aculeata) pulp oil. The MOPN was obtained from green leaves, and the pH, color, water activity, humidity, fixed mineral residue, proteins, lipids, and extraction effectiveness were determined. MOPN was employed as a partial or total replacement of AG in the microencapsulation of bocaiuva pulp oil. Dehydrated and wet mucilages were used to emulsion formation. The interaction between biopolymers, the effectiveness, efficiency of microencapsulation, and the morphological characteristics of microcapsules were confirmed. In addition, the bioactive compounds (chlorophyll and β-carotene) and antioxidant activity were evaluated. The microcapsules were produced using moist mucilage. Microcapsules obtained with AG/gelatin/ bocaiuva oil were considered as control samples. MOPN showed brown color and chlorophyll content of 72.44±5.74 mg 100 g-1. The interaction between AG and MOPN in microcapsule formation was proven for the formulations with 25 and 50% MOPN substitution. The effectiveness was 74.83 and 75.22%, and encapsulation efficiency was 79.18 and 74.59%, respectively, verified through optical micrograph. In addition, the microcapsules with 25 and 50% MOPN as wall material showed three times more antioxidant activity against ABTS, and two times more β-carotene compared to the control microcapsule.

Prospects of earthworm coelomic fluid as a potential therapeutic agent to treat cancer.

Cancer is a major public health concern because it is one of the main causes of morbidity and mortality worldwide. As a result, numerous studies have reported the development of new therapeutic compounds with the aim of selectively treating cancer while having little negative influence on healthy cells. In this context, earthworm coelomic fluid has been acknowledged as a rich source of several bioactive substances that may exhibit promising anticancer activity. Therefore, the objective of the present review is to evaluate the findings of the reported studies exploring the antitumor effects of coelomic fluid in the context of its possible utilization as a natural therapeutic agent to cure different types of cancer. The possible mechanisms underlying the coelomic fluid's anticancerous potential as well as the possibility for future development of cutting-edge therapeutic agents utilizing coelomic fluid-derived natural bioactive compounds to treat cancer disorders have been discussed along with future challenges. In addition, the feasibility of encapsulation of bioactive compounds derived from coelomic fluid with nanomaterials that could be further explored to attain more effective anticancer competence is discussed.

PH-Responsive Chitosan-Doped ZnO Hybrid Hydrogels for the Encapsulation of Bioactive Compounds in Aquaculture.

In this study, we synthesized and characterized pH-responsive Chitosan-AgCl-doped ZnO hybrid hydrogels and evaluated their potential for loading aquaculture bioactive compounds, and assessed their antimicrobial properties against a threatening pathogen associated with disease across a broad spectrum of warm water fish and invertebrates. Hydrogel characterization consisted of assessing morphology via SEM, composition via EDS, hydrogels' network components interactions via FT-IR and pH response through swelling behavior determinations. The swelling characterization of the synthesized hydrogels demonstrated a pH-responsive behavior, showing that low pH values caused the hydrogel polymeric network to expand and capture more of the aqueous solution. These characteristics make the synthesized hydrogels suitable for the encapsulation and controlled release of drugs and bioactive compounds in aquaculture. Chitosan_ZnO hybrid hydrogels showed great antimicrobial activity against Vibrio harveyi, even better than that of loaded PB hydrogels. Here, we provide evidence for the potential capacity of Chitosan_ZnO hybrid hydrogels for the preventive and curative treatment of diseases that impact aquaculture animal health and prevent drug resistance by bacteria.

ZnO nanoparticles impregnated with Hibiscus sabdariffa L. extract: Characterization and antimicrobial activity

Zinc oxide can be a vehicle for the encapsulation of bioactive compounds obtained from Hibiscus sabdariffa L by-products due to its mesoporous structure. The nanoparticles obtained with zinc nitrate showed an average particle size of 120 mn, when impregnated with ultrasound-assisted extract of Jamaican by-product did not show morphological alterations, however; it was observed that there is a modification of the ZnO energy bands attributed to the interactions between ZnO and the extract molecules. T1.0% and T1.5% presented higher inhibition on Listeria Monocytogenes, Staphylococcus aureus, Escherichia coli and Staphylococcus mutans compared to T0.5% and EUSJ. The results show that the synthesis process and the impregnation of Jamaican by-product extracts have interesting antibacterial properties associated with the potentiating effect of ZnO and extract, which can be a starting point for further studies on some applications or other types of microorganisms