Designing bio-nanocomposite hydrogels that combine structural performance with controlled bioactive release remains a key challenge in functional polymer science. In this work, we developed a crosslinked nanocomposite hydrogel system based on chitosan-tuna protein interactions, in which chitosan nanoparticles (CsNP) and phycocyanin-loaded chitosan nanoparticles (Ph-CsNP) were incorporated as reinforcing nanoparticle agents. The nanoparticles were first prepared by ionotropic gelation and thoroughly characterized in terms of colloidal properties such as particle size, zeta potential, and polydispersity index, as well as encapsulation efficiency. The resulting Ph-CsNP were then incorporated into the matrix of a glutaraldehyde crosslinked composite, and the effect of nanoparticle loading on the viscoelastic, mechanical, structural and thermal properties of the hydrogel network was systematically explored. The results revealed that both CsNP and Ph-CsNP are reinforcing agents, enhancing the network integrity and swelling capacity, and thus emphasizing the interactions between the polysaccharide and the protein at the interface, which define the composite architecture. Release kinetics analysis revealed that phycocyanin release from both formulations followed a diffusion-controlled Fickian mechanism, whereas incorporation into the hydrogel matrix further prolonged release and improved bioactive retention in the HG-20(Ph-CsNP) formulation. Overall, these findings highlight the potential of incorporating nanoparticle reinforcement with biopolymer composite engineering to develop tunable polymeric matrices exhibiting programmable release behavior. Such systems represent promising candidates for functional biomaterials and controlled bioactive delivery, although additional biological studies are needed to validate their biomedical potential.

A novel alkaline-stable protease designated BS2 was purified from a newly isolated bacterium, Bacillus safensis S406, through ammonium sulphate (40–60

Aims: This study aimed to explore the gelling capacity of European eel protein isolate (EPI) through the formulation of novel emulsion protein isolate-based gel (EPIGs) and to evaluate how fortification with bioactive European eel oil (EO) could influence the structural and functional properties of acid-induced gels. Methods: EPIGs were prepared by heat treatment (90°C/60 min) of EPI dissolved in acetic acid (20%, v/v). followed by emulsification with EO at two distinct ratios: 1:2 and 1:4 (EO: EPI, w/w). The resulting gels were characterized using Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), texture analysis, and scanning electron microscopy (SEM). Results: A 4% EPI solution in acetic acid formed a gel at 54°C, indicating superior thermal stability and approving strong gelling potential. FTIR analysis confirmed the successful incorporation of EO into the gel matrix, while TGA revealed a slight increase in thermal degradation onset temperatures with higher EO content (from 375°C for EPIG1:4 to 382°C for EPIG1:2). Texture analysis showed that EO incorporation slightly enhanced gel elasticity (from 12.93 mm to 13.19 mm), attributed to interactions between oil droplets and the protein matrix. SEM microstructural evaluation indicated that higher EO amount (EPIG1:2) resulted in larger pore formation, whereas EPIG1:4 exhibited a more compact, less porous structure. Keywords: European eel; Emulsion Protein Isolate-based Gel; FTIR; Thermogravimetric; SEM.

Selenium nanoparticles (SeNPs) attract considerable attention for their promising applications in the biomedical field, driven by their unique properties and antioxidant activities. However, their practical use is often hindered by issues such as instability and aggregation. In this study, a polysaccharide, P2, extracted from Ononis natrix, was used to stabilize SeNPs to address these limitations. P2-SeNPs were prepared through a green synthesis method involving sodium selenite, P2, and ascorbic acid, and characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR) spectroscopy, and X-ray diffraction (XRD). P2-SeNPs exhibited a smaller particle size and enhanced stability compared to unmodified SeNPs. UV-Vis spectroscopy and X-ray photoelectron spectroscopy (XPS) demonstrated the presence of Se–O bonds, suggesting effective stabilization by covalent bonding between SeNPs and P2. Stability tests revealed that P2-SeNPs maintained good dispersion under various conditions, with optimal stability observed at refrigerated temperatures and neutral pH. Moreover, P2-SeNPs exhibited better antioxidant activities than unmodified SeNPs, as evidenced by higher DPPH radical scavenging, ABTS radical scavenging, and metal chelation ratios. This difference is attributed to both the reduced aggregation and smaller size of P2-SeNPs. Therefore, it is concluded that P2-SeNPs exhibit significant potential as an effective antioxidant agent for biomedical applications.

Composite hydrogels were synthesized using carboxymethyl chitosan (CMCh) and polysaccharides (PS) extracted from Ononis natrix through chemical cross-linking with genipin, a naturally derived cross-linker. Hydrogels with different PS/CMCh ratios were characterized in terms of their structural, morphological, thermal, rheological, and biological properties. The results showed that an increase in PS concentration enhanced both the swelling capacity and viscoelastic properties of the hydrogels. In vitro drug release was carried out using ascorbic acid (Aas) and curcumin (Cur) as model of hydrophilic and hydrophobic bioactive molecules, respectively. Drug loading was achieved by immersion of lyophilized hydrogel in a drug solution. The release profiles showed a higher release rate at physiological pH (7.4) compared to acidic pH (5.5) due to enhanced hydrogel swelling under neutral conditions. Modeling with Korsmeyer-Peppas equation revealed Fickian diffusion-controlled release for Aas and non-Fickian diffusion-controlled release for Cur. Moreover, the composite hydrogels displayed notable antioxidant activity, and Aas-loaded hydrogel exhibited antibacterial effects against Staphylococcus aureus, highlighting their promise in counteracting oxidative damage and microbial infection, two crucial factors in the wound healing process. Therefore, it is concluded that the PS/CMCh composite hydrogel presents great potential for the development of biomaterials from renewable resources for controlled drug delivery systems and wound care applications.

The objective of this research was to assess the impact of distinct drying techniques, specifically freeze drying (FD) and spray drying (SD), on the physicochemical, functional and biological properties of collagenous protein isolate derived from bluefin tuna (CPI). The freeze-dried sample (CPI-FD) displayed superior emulsification contributing to its higher solubility. In contrast, the spray-dried sample (CPI-SD) exhibited the highest foaming capacity and stability, attributed to the smaller particle size generated by the SD process. CPI-FD demonstrated greater gelation capacity, characterized by a lower gelation concentration (LGC), indicating gels prepared with CPI-FD had higher elastic and viscous moduli compared to those from CPI-SD. In summary, diversely dried CPIs showcased intriguing functional, physical, and biological properties, thereby underlining their potential utility in a range of applications, particularly within the food industry as a nutritional ingredient.

The food packaging sector is focused on developing innovative materials to enhance food safety and quality while reducing environmental impact. Accordingly, this study aimed to develop packaging based on bovine gelatin (G) blended with crude sweet orange juice pomace pectin (SOPP) at different ratios (G/SOPP = 85/15, 65/35, 50/50, w/w). The obtained crude SOPP was highly methylated and exhibited antioxidant and antibacterial properties due to the presence of galacturonic acid (<70%) and phenolic compounds (58.2 +/- 0.8 mg/g SOPP). High-performance liquid chromatography with diode array detection analysis revealed the presence of hesperidin, catechin, and naringin as major phenolic compounds in SOPP. Further, the incorporation of this latter improved gelatin-based packaging structural homogeneity, opacity, water vapour barrier features, glass transition temperature and tensile strength. G-SOPP (50/50) film showed efficient antibacterial activity against Escherichia coli and Bacillus subtilis and high antioxidant potential reaching values of 0.7, 48.7%, 76.7% and 68.9% for reducing power, ss-carotene bleaching inhibition, DPPH (2,2-diphenyl1-picrylhydrazyl) and ABTS+ (2,20-azinobis-[3-ethylbenzothiazoline-6-sulphonic acid]) radicals scavenging activities, respectively. Another interesting finding is that the combination of G and SOPP reduced the oil solubility of G-SOPP films suggesting great physical integrity of the film over 63 days. The polyphenol content released from G-SOPP blend film in a fatty simulant increased as SOPP content of films was increased. G-SOPP (50/50) film, designed as a pouch, delays the photooxidation process of virgin olive oil over 63 days of storage time, without altering its organoleptic properties. Overall, these outstanding results highlighted the potential use of gelatinpectin blend films for active packaging of oils and lipid-based foods.

Polysaccharides were extracted from Ononis natrix leaves using various methods, including hot water maceration (HWM), ultrasound-assisted extraction (USE), enzyme-assisted extraction (ENE), combined enzyme-ultrasound (EUS) and combined maceration-ultrasound (MUS) treatment. The extracted crude polysaccharides were characterized in terms of physicochemical, structural, techno-functional features, and biological activities. HWM extraction showed the highest yield (13.7 ± 0.3

In this work, silver nanoparticles (AgNPs) were elaborated using a simple, low-cost, and reproducible method by thermal treatment at 90°C of chitooligosaccharides (COSs), produced by chitosan depolymerization using the digestives chitosanases from Portunus segnis viscera, in the presence of AgNO3. The characterization of the obtained AgNPs, using UV–visible spectroscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS), and Fourier-transform infrared (FTIR) spectroscopy analyses, showed that they are crystalline, spherical and stable for a month at 4°C. Moreover, the biological properties of the synthesized AgNPs were evaluated, proving that they exhibited interesting antioxidant and antibacterial activities. The present investigation suggested that COSs will be a good source for the preparation of AgNPs that could be useful in different industrial and biomedical applications.

Marine-derived protein hydrolysates and bioactive peptides are receiving increased interest for their human health-promoting effects. In fact, biopeptides are extensively described in the literature to be owned with strong activities that may treat and/or prevent different diseases. Current trends are addressed toward the production and purification methods of bioactive peptides, which are delicate and almost performed at laboratory scale and limited their large-scale production for marketing purposes. Besides in vitro and in vivo experiments, in silico studies based on simulation using bioinformatics strategies are providing large amounts of data related to the screening of peptide activity, the production method (enzyme(s) and protein parent selection), structure–activity relationship, and bioavailability, resulting in a new cost-effective scientific strategy. However, in silico findings should be confirmed in vitro after peptide synthesis and addressed to clinical assays. In this sense, the present chapter provides an overview on the recent researches on the production of seafood-derived hydrolysates and biopeptides, their structural characteristics involved in the studied biological activities, and their potential applications in food and nutraceutical areas.

The defatted viscera from smooth hound were the raw material used to produce four protein hydrolysates using three different microbial proteases (Neutrase, Esperase and Purafect) and the endogenous enzymes, named VPH-N, VPH-E, VPH-P and VPH-EE, respectively. Hydrolysates showed different degrees of hydrolysis (DH) depending on the enzyme used, where the VPH-P had the highest DH (30

In the present study, sulfated polysaccharides (SPs) from smooth hound shark were extracted using different precipitation agents, the cetylpyridinium chloride (CPC) or ethanol, named SHSP-I and SHSP-II, respectively. The UV-visible scan demonstrated the absence of nucleic acids or proteins in the extracted SHSPs. The antioxidant, anticoagulant and anti-proliferative activities were also investigated. Results showed that SHSPs displayed reducing and scavenging capacities, as shown by the oxygen radical absorbance capacity, the total antioxidant capacity and the hydroxyl radical-scavenging activities. Moreover, extracted SPs were able to prolong the activated partial thromboplastin time (aPTT), the prothrombin time (PT) and the thrombin time (TT) and they reduced the fibrinogen level (FL), without inducing erythrocytes hemolysis, which indicated that they inhibited the intrinsic and extrinsic coagulation pathways and the thrombin-mediated fibrin formation. The SHSP-I was more effective on prolonging the blood clotting time, by more than 120 s at 1 mg/ml in the aPTT and about 70 s and 60 s at 2.5 mg/ml in the PT and TT, respectively, compared to the SHSP-II. The anti-proliferative activity of SHSPs was tested against the growth of K562 human myelogenous leukemia cells and Caco-2 colon cancer cells. Data showed that both polysaccharides have a dose-dependent inhibitory effect, where SHSP-I exhibited the strongest activity against the tested cells and the K562 was more sensitive than Caco-2 line cells to the action of SHSPs. The overall data suggested that SPs from shark viscera could be useful as natural nutraceutical agents.

The present work aims to quantitatively and qualitatively monitor the production of lipopeptide mixtures by Bacillus methylotrophicus DCS1 strain in Landy medium and to investigate the antifungal activities of DCS1 strain and its produced lipopeptides. The in vitro activities were tested by the direct confrontation and agar well diffusion methods, while the in vivo study was carried out in order to test the efficiency of DCS1 bacterial suspension in the control of Fusarium wilt in tomato plants. Identification of lipopeptides by mass spectrometry (LC/MSD-TOF) showed that lipopeptide isoforms produced during the first 24 h and 48 h of fermentation are identical, belonging to bacillomycin D and fengycins A and B homologues with a difference in the yield of production. After 72 h of fermentation corresponding to the end of incubation period, B. methylotrophicus DCS1 is able to produce a mixture of surfactin, pumilacidin, iturin A/mycosubtilin, iturin C1, bacillomycin D and fengycins A and B isoforms. The results of in vitro antifungal experiments suggest that B. methylotrophicus DCS1 has a significant potential as a biocontrol agent, owing to lipopeptides produced, endowed with antifungal activity against several phytopathogenic fungi. The curative treatment of tomato plants with DCS1 bacterial suspension was more effective in the protection against Fusarium oxysporum f. sp. radicis-lycopersici (FORL) than the preventive treatment by comparing the average number of leaves remaining healthy after 30 days of each treatment and the appearance of tomato plants roots. The results indicate that B. methylotrophicus DCS1 exhibit a significant suppression of Fusarium wilt symptoms in tomato plants comparable to that of commercial fungicides and could be an alternative to chemically synthesized pesticides.

Food packaging must guarantee the products' quality during the different operations including packing and maintenance throughout transportation and storage until to consumption. Thus, it should satisfy, both, food freshness and quality preservation and consumers health safety. Natural bio-sourced polymers have been explored as safe edible materials for several packaging applications, being interestingly carrier of bioactive substances, once added to improve films' properties. Gelatin and chitosan are among the most studied biomaterials for the preparation of edible packaging films due to their excellent characteristics including biodegradability, compatibility and film-forming property. These polymers could be used alone or in combination with other polymers to produce composite films with the desired physicochemical and mechanical properties. When incorporated with bioactive substances (natural extracts, polyphenolic compounds, essential oils), chitosan/gelatin-based films acquired various biological properties, including antioxidant and antimicrobial activities. The emerging bioactive composite films with excellent physical attributes represent excellent packaging alternative to preserve different types of foodstuffs (fruits, meat, fish, dairy products, …) and have shown great achievements. This chapter provides the main techniques used to prepare gelatin- and chitosan- based films, showing some examples of bioactive compounds incorporated into the films' matrix. Also, it illustrates the outstanding advantages given by these biomaterials for food preservation, when used as coating and wrapping agents.

This experiment aimed to investigate the effects of dietary supplementation of saffron petal (SP) on lactation performance, nutrients digestibility, and antioxidant status of dairy goats. Eighteen multiparous Saanen goats were randomly divided into three groups and fed with one of experimental diets containing 0 (control), 1.5, and 3% of SP (DM basis). Dry matter intake (DMI) and milk yield were recorded daily. The individual blood samples were collected on days 0, 21, 42 and antioxidant capacity was measured in blood. The milk samples were collected on weeks 1, 3 and 6 of the trial and analyzed for antioxidant status. DMI, body weight (BW) and nutrients digestibility were similar following SP ingestion. Compared with control, supplementation with 3% SP increased milk production (P < 0.05). Of all milk components, only the protein content was increased (P < 0.05) in goats receiving 3% SP diet. Plasma glucose and cholesterol decreased (P < 0.05) in goats fed 3% SP. The plasma malondialdehyde (MDA) was depressed and total antioxidant capacity (TAC) was enhanced in both plasma and milk of goats fed 3% SP. Likewise, the activity of glutathione peroxides (GPx) was enhanced (P <= 0.05) with 3% SP supplementation, however, no differences were observed for the activity of superoxide dismutase (SOD) in the blood. Overall, the findings implied that SP supplementation (up to 3% DM of diet) for lactating goats increased milk yield and improved the antioxidant status of blood and milk without deleterious effects on DMI and nutrients digestibility.

The present work deals with the development of novel biopolymer-based composite hydrogels (HGs) based on chitosan and protein isolate derived from marine byproducts, and their functional applications. Chitosan (Cs) from blue crab shells and bluefin tuna protein isolate (BTPI) were selected to prepare composite hydrogels. The data from the characterization demonstrated that by increasing the BTPI content to 20% (w/w, Cs), hydrogels became more porous, elastic, and mechanically stable. Furthermore, all HGs present good antioxidant activity in a BTPI concentration-dependent manner. Based on the overall structural, swelling, and mechanical properties, HG-20 was selected for in-vitro release study of phycocyanin. Release patterns show that HG-20 is able to release phycocyanin (Ph) under acidic and neutral microenvironments. The local application of HG-20 loaded or not by Ph for wound repair in rats' models was further studied. All tested HG exhibited an interesting wound healing-promoting ability. Importantly, Ph-loaded HG-20 has been found to accelerate wound closure, compared to unloaded HG-20.

Lipopeptides from Bacillus methylotrophicus DCS1 are endowed with interesting properties. The composition of production medium and culture conditions were optimized by studying the effect of 14 variables in a 23 run Plackett-Burman design (PBD) to screen for key factors with the aim of improving lipopeptides yield and surface activity with low production costs. In PBD, four significant factors (Urea, CaCl2, gruel and temperature) affecting the production, were choosed for further optimization and constructed via Box-Behnken design (BBD). Enhanced lipopeptides production was carried out using gruel as carbon source at a concentration of 40 g L-1 and urea as nitrogen source at a concentration of 5.5 g L-1. The optimal conditions were 33 °C temperature, pH 7.5, an agitation of 175 rpm and 2.5% inoculum size. Utilizing the predicted optimized conditions, the maximum lipopeptides yield of 4.7 g L-1 was reached which accord well with the predicted value.

Hydrogels based on natural polysaccharides represent a growing group of suitable biomaterials for the elabo-ration of effective wound healing dressings, especially for the treatment of chronic wounds. This work was intended to prepare a polysaccharide-based hydrogel for diabetic wound healing which would help maintain the well-being of diabetes and improve their quality of life. For this purpose, a pectic polysaccharide (OPS) was extracted and purified, for the first time, from Tunisian okra pods and its physicochemical and rheological features, antioxidant and in vivo and in vitro wound healing activities were investigated. OPS, an acidic poly-saccharide with a molecular weight of 3.28 x 106 Da and a polydispersity index of 1.03, was mainly composed of galactose (24.45 %), galacturonic acid (24.6 %) and rhamnose (18.25 %). Combined with FT-IR and NMR an-alyses, it consisted of a pectic rhamnogalacturonan I (RG-I) structure with galactan side chains. The OPS demonstrated antioxidant potential, gelling ability, cytocompatibility properties, non-cytotoxicity and cell migration and proliferation promoting activities, which met the requirements for wound dressings. Then, the in vivo cutaneous wound healing effect of OPS-based hydrogel was investigated using an alloxan-induced diabetic rat model, and results showed that it significantly accelerated the wound healing process by acting in the ac-celeration of the recovery of the dermis and inducing more blood vessels formation and tissue granulation. Overall, these results provide new insights into the development of a promising and effective okra pectin-based hydrogel for the treatment of chronic diabetic wounds.