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The marine Bacteroidota Zobellia galactanivorans has a polysaccharide utilization locus dedicated to the catabolism of the red algal cell wall galactan carrageenan and its unique and industrially important α‐3,6‐anhydro‐D‐galactose (ADG) monosaccharide. Here we present the first analysis of the specific molecular interactions that the exo‐(α‐1,3)‐3,6‐anhydro‐D‐galactosidase ZgGH129 uses to cope with the strict steric restrictions imposed by its bicyclic ADG substrate — which is ring flipped relative to D‐galactose. Crystallographic snapshots of key catalytic states obtained with the natural substrate and novel chemical tools designed to mimic species along the reaction coordinate, together with quantum mechanics/molecular mechanics (QM/MM) metadynamics methods and kinetic studies, demonstrate a retaining mechanism where the second step is rate limiting. The conformational landscape of the constrained 3,6‐anhydro‐D‐galactopyranose ring proceeds through enzyme glycosylation B1,4→[E4]≠→E4/1C4 and deglycosylation E4/1C4→[E4]≠→B1,4 itineraries limited to the Southern Hemisphere of the Cremer–Pople sphere. These results demonstrate the conformational changes throughout catalysis in a non‐standard, sterically restrained, bicyclic monosaccharide, and provide a molecular framework for mechanism‐based inhibitor design for anhydro‐type carbohydrate‐processing enzymes and for future applications involving carrageenan degradation. In addition, our study provides a rare example of distinct niche‐based conformational itineraries within the same carbohydrate‐active enzyme family. [ABSTRACT FROM AUTHOR]

AbstractThis study is aimed to evaluate the impact of methanolic extract of Artemisia vulgaris and isolated plant compound, β-Caryophyllene oxide against carrageenan-induced paw edema in rat model and its therapeutic potential compared with reference drug, Indometacin. Methanolic extract of A. vulgaris was characterized using FTIR, LC-MS, NMR spectral studies. Paw edema was induced by sub-plantar injection of 100 µl of 1% carrageenan. Oxidative enzymes, such as super oxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR), lipid peroxidation and C-reactive protein levels were measured in paw tissue. In silico evaluation of anti-inflammatory activity of plant compounds was evaluated against the molecular targets of inflammation. C-reactive protein and lipid-peroxidation levels were significantly increased whereas the activity levels of oxidative enzymes were significantly decreased in inflammation-induced rats. The recovery of oxidative enzyme levels was seen in treated groups in a dose dependent manner. C-reactive protein and lipid-peroxidation levels were significantly decreased in treated groups, indicating the anti-inflammatory activity of the plant extract and the plant compound. Computational analysis rationalizes the inhibitory ability of plant derived compound possibly by altering the inflammatory signaling pathway. [ABSTRACT FROM AUTHOR]

PVA‐κcarrageenan (κCar) gel is widely used in the pharmaceutical field for transdermal drug delivery, enhancing drug stability and bioavailability. This study aims to modify PVA‐κCar gel by introducing tannic acid. Lidocaine was used as a model drug for incorporation into the novel gel. The PVA‐κCar matrix was mixed with tannic acid prior to freeze– thaw cycle to create a gel composite. The physicochemical features of this gel were evaluated using FTIR, XRD, thermal analysis, and SEM. The presence of tannic acid has reduced the thermal stability of PVA‐κCar from 84 to around 70 °C. The gel content of tannic acid‐modified PVA‐κCar was 34.6% (A) and 52.1% (B). The addition of tannic acid substantially increased gel viscosity. Cytotoxicity analysis showed that tannic acid‐modified PVA‐κCar gel did not affect the viability of HCT colon cancer cells. The encapsulation efficiency of lidocaine in tannic acid‐modified PVA‐κCar was 13 ± 0.2% (A) and 12 ± 0.5% (B), while the drug loading was 0.96 ± 0.01 (A) and 0.91 ± 0.02 (B). In vitro release of lidocaine from the modified PVA‐κCar exhibited a sustained release mechanism in phosphate‐buffered saline solution. These findings indicate that the gel possesses advantageous characteristics as a drug carrier. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION This study investigated the contribution of 11 polysaccharides (2%, w/w), including pectin (PC), κ‐carrageenan (KC), ι‐carrageenan (IC), gellan gum (GG), guar gum (GM), sodium alginate (SA), konjac gum (KG), gum arabic (GA), fucoidan (FC), locust bean gum (LBG), and curdlan (CD), to the gel and microstructural properties of Meretrix meretrix clam gel (MMG).The hardness, springiness and chewiness of MMG with KC, IC, GG, SA and FC addition increased by ~10%–250%, while PC, GM, KG and LBG groups decreased by ~0.6% to 69%. KC, IC, SA, GG and FC decreased the cooking loss rate (CLR) by 69.4% to 88.7% and correspondingly enhanced the water holding capacity (WHC) by 10.2% to 21.4%, which was accompanied by an increased bound water and immobilized water area and high hydrogen proton density. The addition of KC transformed the MMG microstructure from a loose network with large pores to a compact, dense network, reducing lacunarity by 57.9%. The primary intermolecular forces in MMG with the incorporation of KC, IC, GG, SA and FC were hydrophobic interactions and disulfide bonds, which increased by 32.8%‐105.3% and 45.6%‐114.5% than MMG alone, respectively.Collectively, KC, IC, GG, SA and FC could improve the gel properties of MMG and the strongest synergistic combination was found in the MMG/KC system. This study suggests that the incorporation of polysaccharides is a strategy with potential for modifying the gel properties of shellfish surimi products. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Biopolymer based water‐in‐oil‐in‐water double (W1/O/W2) emulsion systems comprise a complex emulsion system that might be affected by several factors and the status at multiple phases. The present study investigated the physicochemical properties of W1/O/W2 double emulsions with inner W1 phase incorporated with various polysaccharides and the outer phase stabilized by whey protein isolate (WPI). Six different polysaccharides were selected as co‐emulsifiers in the inner phase, and their effects on morphology, droplet size, zeta potential and rheology properties were evaluated. Furthermore, the impact of WPI/polysaccharide concentration and pH on the physicochemical properties and storage stability of the emulsions was compared. RESULTS: Emulsions with an inner phase incorporated with xanthan gum and carrageenan exhibited better stability than others. Increasing the concentration of WPI enhanced the overall stability of the double emulsion, although it compromised the integrity of the internal W1/O interface. On the other hand, a 1.0% concentration of polysaccharide, specifically when carrageenan is used, slowed down droplet floating and coagulation. An acidic external aqueous phase (pH 4) led to larger and more uniform particle size distributions, as well as enhanced stability. The lower pH decreased the viscosity and delayed molecular exchange in the oil phase, thereby preserving the structure of the double emulsion. CONCLUSION: These findings contribute to a better understanding of the factors influencing the stability and properties of W1/O/W2 double emulsions with addition of anionic polysaccharides in the inner water phase. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Due to their biocompatibility and biodegradability, polysaccharide-based aerogels produced through supercritical fluid drying attract a lot of attention in the food industry, pharmaceuticals, tissue regeneration, etc. The aim of this study is to systematically review the types of polysaccharides used for aerogel fabrication, the approaches to their gelation before supercritical fluid drying, and the conditions of the drying. The literature screening was conducted according to the PRISMA protocol to give a full picture. Aerogels can be made using a wide range of polysaccharides (alginates, chitosan, agar, cellulose, carrageenans, starch, pectin, chitin, b-glucans, xanthan, guar gum, gellan gum, hyaluronic acid, tragacanth gum, locust bean gum), as well as polysaccharide-based biomaterials and artificial composites containing inorganic substances. The natural origin of the polysaccharides and a diversity of their chemical structure allow to explore a wide range of processing conditions for fabrication of aerogels for various applications. Different strategies to dissolve and gel the polysaccharides, aiming to reduce a number of required steps to aerogel formation and control its morphology, were reported. An analysis of the protocols used for supercritical drying of the formed gels showed trends toward process simplification and the implementation of one-pot strategies, as well as the better control over aerogel morphology, which open up opportunities for a wide application of polysaccharide-based aerogels in practice. [ABSTRACT FROM AUTHOR]

Plastic food packaging causes massive pollution in the environment via resource extraction, gas emissions, and the enduring plastic waste accumulation. Hence, it is of crucial importance to discover sustainable alternatives in order to protect ecosystems and conserve precious resources. Recently, seaweed has been emerging as a promising sustainable solution to plastic pollution. Seaweed is a fast-growing marine plant that is abundant in tropical coastlines and requires minimal resources to cultivate. In addition, seaweed is rich in valuable polysaccharides such as alginate, fucoidan, carrageenan, agar, and ulva, which can be extracted and processed into biodegradable films, coatings, and wraps. This ability allows the creation of an alternative to plastic food packages that are completely biodegradable, made from renewable resources, and do not linger in landfills or oceans for centuries. In this context, this review discusses the main classification of seaweed, their production and abundance in the world, and provides a summary of seaweed-based materials developed in the last 2–5 years for potential usage in the food packaging sector. [ABSTRACT FROM AUTHOR]

The main goal of this work was to develop bio-based and ecofriendly intelligent films as freshness indicators to monitor European hake (Merluccius merluccius) quality during storage by using a visual, non-destructive, and real-time technique. Locust bean gum (LBG)/κ-carrageenan (Car) films incorporating blueberry extract (BLE) or beetroot extract (BEE) were developed and their effectiveness to detect hake deterioration during 7 days of storage at 4 °C was evaluated. A visible color response from pink to blue was observed on the BLE films at the end of hake storage, which correlated with the hake deterioration profile, namely an increase in pH values (from 6.60 ± 0.04 to 8.02 ± 0.03), total viable count (TVC, from 4.61 ± 0.36 to 8.61 ± 0.21 log CFU/g), and total volatile basic nitrogen content (TVB-N, from 10.21 ± 1.97 to 66.78 ± 4.81 mg/100 g) beyond the spoilage threshold. The results of this study are very promising, since it was possible to develop a new effective intelligent bio-based responsive indicator film incorporating natural dye BLE, which has the potential to contribute to food waste reduction and improve food safety by detecting the hake freshness status. [ABSTRACT FROM AUTHOR]

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Simple Summary: Chicken liver pate is a smooth and spreadable product made from chicken meat, chicken livers, fat, seasoning and other optional ingredients (such as hydrocolloids). Hydrocolloids (polysaccharides or proteins) are commonly used in spreadable meat/poultry products (such as chicken liver pâté) to improve texture, stability and moisture retention, resulting in a product with desired functional and organoleptic properties. In general, the chicken liver pâté samples showed their highest hardness and viscoelastic moduli values when κ-carrageenan and furcellaran were used. Suggestions for producing a softer chicken liver pâté consistency involve utilizing ι-carrageenan at a level between 0.25% and 0.75% (w/w) or furcellaran at a 0.25% w/w concentration. We can conclude that the use of hydrocolloids in the manufacturing of chicken liver pâté could be an effective solution leading to the development of products with desired techno-functional properties. Hydrocolloids are used in spreadable meat or poultry products to improve consistency, emulsion stability and water retention, resulting in products with desired functional and organoleptic properties. The scope of the work was to evaluate the addition of three divergent algal hydrocolloids (κ-carrageenan, ι-carrageenan, furcellaran) at four different concentrations (0.25, 0.50, 0.75, and 1.00% w/w) on the physicochemical, textural, rheological and organoleptic properties of model chicken liver pâté (CLP) samples. Overall, the highest hardness and viscoelastic moduli values of the CLP samples were reported when κ-carrageenan and furcellaran were utilized at a concentration of 0.75% w/w (p < 0.05). Furthermore, increasing the concentrations of the utilized hydrocolloids led to increase in the viscoelastic moduli and hardness values of CLP. Compared to the control sample, an increase in spreadability was reported in the CLP samples with the addition of hydrocolloids. Finally, the use of algal hydrocolloids proved to be an effective way to modify the techno-functional properties of CLP. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the feasibility of producing electrospun fibers by combining polysaccharides, zein, and poly(ethylene oxide) (PEO) to simulate the fibers applied in plant-based meat analogs. The rheological properties of biopolymer solutions were evaluated, and the electrospun fibers were characterized according to their morphology, structural interactions, and thermal analysis. The results indicated that the fibers prepared in a ratio of 90:10 of zein/carrageenan from the mixture of a solution containing 23 wt.% of zein with a solution containing 1 wt.% of carrageenan and with the addition of 1 wt.% of PEO presented a promising structure for application as fibers in meat analogs because they have a more hydrophilic surface. Thus, they have good moisture retention. In addition, they have good thermal stability at high temperatures, which is crucial to achieve a consistent and pleasant texture. Furthermore, it was observed that adding zein and PEO helps with the spinnability of the polysaccharides, producing fibers with good homogeneity. [ABSTRACT FROM AUTHOR]

AbstractThe crude extract and the relative fractions and subfractions from the aerial parts of Anabasis articulata were isolated and analyzed by Gas Chromatography-Mass Spectrometry, in order to characterize their content of alkaloids. Six alkaloids belonging to three families, the tetrahydroisoquinolines, the phenethylamines, and the indole-alkaloids, were identified for the first time in A. articulata. All the extracts were subjected to four in vitro antioxidant assays and an in vivo anti-inflammatory test. Overall, the crude extract showed the highest antioxidant activity by FRAP and TAC assays, while DPPH and ABTS tests registered this record to the expense of its alkaloidal fraction. Moreover, the alkaloid-rich extract also exhibited a significant anti-inflammatory effect on carrageenan-induced rat paw edema, reaching the highest percentage of inhibition at the concentration of 150 mg/kg of body weight overtaking diclofenac (50 mg/kg BW) used as a positive control. All these results suggest that A. articulata is a promising source of alkaloids compounds, which could be helpful in the management of oxidative stress and associated damage, including the onset of inflammatory conditions and might be used for the development of new therapeutic strategies aimed at fighting pathologies based on inflammation. [ABSTRACT FROM AUTHOR]

Bioplastics are biobased or biodegradable plastic synthesized from natural resources with similar features to conventional plastic and environmental sustainability. Seaweed species abundant in the coastal regions of Bangladesh are yet to be explored for developing biodegradable plastic to solve the plastic pollution problem. Semi‐refined kappa carrageenan was extracted from Gracilaria sp. with Pressurized Hot Water Extraction (PHWE) and blended with sorbitol and polyethylene glycol 1540 in this study, respectively. The presence of carrageenan and other functional groups was confirmed with FTIR analysis. The bioplastic films showed over 90 % biodegradability after 16 days of soil burial test and 98 % water solubility after immersion for 16 days. Maximum 20 MPa tensile strength and 44 % elongation were observed from the bioplastic films. The polyethylene glycol 1540 blended films showed better physical and mechanical properties. SEM analysis was conducted to evaluate the influence of tensile strength and elongation on the surface integrity of the bioplastic films. The findings indicate that Gracilaria sp. found in the coastal regions of Bangladesh, can be a potential candidate for developing bioplastics for food packaging and many other applications. [ABSTRACT FROM AUTHOR]

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Background: Blackgrm is one of the most important pulse crops majorly cultivated in rainfed conditions of India. Soil moisture deficit, low and erratic rainfall, use of poor quality seeds, poor crop stand and improper crop management resulting in lower productivity in rainfed ecosystem. Reduced crop stand alone leads to 30% deficit in production. Availability of technology to overcome drought stress is one of the way to expand blackgram cultivation in dry tracks. Hydrophilic polymers may have great potential in restoration and reclamation, when used the polymers correctly and an ideal situations will have atleast 95% of their stores water available for plant absorption. There are N number of inorganic polymers available in the market, that can be applied in the form of soil application. Studies on Hydrophilic bio polymer seed coating to mitigate water stress is very megar or nil. Hence, the present study was formulated in blackgram as hydrophilic bio polymer seed coating on seed germination and field emergence. Methods: Seed coating experiment consists of seven hydrophilic biopolymers (Ethyl cellulose, Methyl cellulose, Carboxyl methyl cellulose, Agar, Gum Arabic, Xanthangum and Carrageenan); two coating methods (dry and dry powder concoction). The germination test conducted in sand media with 60% Water Holding Capacity of sand and PEG induced water stress and evaluated for seed quality parameters against uncoated seeds. Field experiments conducted with water stress periods of 10 days, 20 days and 25 days after life irrigation and observed for biometric and yield parameters. Result: Results revealed that blackgram seeds coated with bio polymerconcoctionof xanthan gum : carrageenan : Agar agar (4:1:1) @ 20 g/kg performed better in terms ofall seed quality parameters and withstand water stress upto 20 days after life irrigation with the yield increase of 53% over stressed control (Skipping irrigation for 20 days after life irrigation) and can be recommended as a pre sowing treatment for drought mitigation in blackgram. [ABSTRACT FROM AUTHOR]

Summary: Our study focuses on the gelling properties of pea protein (PP), which are comparatively weaker than those of other plant proteins, thereby limiting its application. However, we found that the addition of κ‐carrageenan (κ‐CAR) significantly (P < 0.05) increased PP gels' hardness and water‐holding capacity irrespective of gel formation temperature (80 or 95 °C). Rheological and microstructural analysis confirmed a synergistic effect between PP and κ‐CAR, with higher synergy values observed in hydrogels formulated at 95 °C. Molecular force studies revealed that non‐covalent interactions were dominant, with disulphide bonds contributing only to the structure of gels formed at 95 °C. These promising findings not only enhance our understanding of the PP and κ‐CAR gel formation mechanism but also hold practical implications, potentially leading to improved gelling properties of PP and expanding its applications in the food industry. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chinese Institute of Food Science & Technology is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Annona Senegalensis Pers. (Annonaceae) is a medicinal plant used to treat many pathologies, including inflammatory diseases and pain. The aim of this study was to investigate the analgesic and anti-inflammatory properties of Annona Senegalensis leaves aqueous extract in mice and rats. The analgesic activity was evaluated using the acetic acid (1%) induced writhing test and formalin (1%) test. The anti-inflammatory activity was performed using the carrageenan and the dextran induced hind paw oedema in rats. The extract induced a significant (p<0.05) and dose-dependent decrease in abdominal contortions compared with control mice. The maximum inhibition was 63.36% at the dose of 200 mg/kg body weight. Only the late phase of formalin induced nociception was significantly inhibited by the extract with a maximum inhibition value of 56.96% at the dose of 200 mg/kg body weight. In the anti-inflammatory investigation, the aqueous extract of the leaves of Annona Senegalensis produced a significant (p<0.05) and dose-dependent decrease in edema induced by carrageenan and dextran. The maximum inhibition was 57.14% obtained at the fifth hour at the dose of 200mg/kg for the carrageenan test. For the dextran test, the maximum inhibition was 59.80% obtained at the second hour at the dose of 200 mg/kg body weight. Our results show that Annona Senegalensis has peripheral analgesic and anti-inflammatory properties. It could therefore be an advantage in alternative medicine. [ABSTRACT FROM AUTHOR]

The treatment of second-degree burn wounds presents a significant clinical challenge, often characterized by prolonged healing times and risk of complications. In this study, the wound healing potential of bioactive marine sulfated polysaccharides ulvan and carrageenan formulated in gels at concentrations of 1.5%, 5.0%, and 10% w/w was evaluated. Hairless female SKH-hr2 mice (n = 7 per treatment) with burn-inflamed skin were treated with the polysaccharide-based gels, and the therapeutic efficacy was assessed using a comprehensive array of evaluation methods, including a histopathological analysis, clinical observation, photo-documentation, an image analysis, an evaluation of biophysical skin parameters, and FT-IR spectroscopy. Our findings indicate that the 10% w/w carrageenan gel exhibited significant enhancement in wound healing, particularly in the early stages of the healing process. This was evidenced by the restoration of the α-helix structure of collagen and the configuration of glycosaminoglycans, as demonstrated by FT-IR absorption bands of the skin both in vivo and ex vivo. Furthermore, the 5% w/w ulvan gel also demonstrated notable efficacy in promoting wound healing, particularly in the later stages of the healing process. These results suggest that carrageenan and ulvan gels hold promise for improving the efficiency of wound healing in second-degree burn wounds. Our study contributes to the understanding of the therapeutic potential of marine polysaccharides and provides insights into their mechanism of action in promoting wound healing. [ABSTRACT FROM AUTHOR]

Bio-degradable, active and intelligent films have sparked interest recently due to its great potential for food freshness monitoring. In this study, antioxidant and intelligent films were developed using carrageenan gum (CG), maize starch (MS), and anthocyanin from fresh Rosa chinensis flower extracts (RFE) and their physical, functional and structural properties were evaluated. The results indicated that incorporation of RFE with different amounts (1.2–3.6 mL/g, on MS basis) significantly increased thickness (0.063–0.092 mm), moisture content (10.16–14.12%), opacity, thermodynamic stability, elongation at break (13.75–28.68%) and decreased water contact angle ( 96.7 - 30.5 ∘ ) and tensile strength (45.48–16.28 MPa) of the films. The structural characterization revealed the formation of intermolecular hydrogen bonds between RFE and MS or CG in MS-CG-RFE films. The MS-CG-RFE films showed excellent pH and ammonia sensitivities with different colors from red to green. The MS-CG-RFE-C film displayed strong antioxidant activity, with a maximum DPPH radical scavenging rate of 71.72%. When employed for pork freshness monitoring, the MS-CG-RFE films showed visible color changes in response to changes of pork freshness. These findings imply that MS-CG-RFE films can be used in antioxidant and intelligent packaging in the food industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Conventional petroleum‐based packaging films cause severe environmental problems. In the present study, bio‐edible film was introduced as being safe to replace petroleum‐based polymers. A food application for edible sachets and a composite edible film (EF) from marine algae, Gracilaria fisheri (GF) extract, were proposed. RESULTS: Carbohydrates were the most prevalent component in fresh GF fronds. Under neutral conditions comprising 90 °C for 40 min, the structure of the extract was determined by Fourier transform infrared to be a carrageenan‐like polysaccharide. Glycerol was the best plasticizer for EF formation because it had the highest tensile strength (TS). The integration of gelatin into the algal composite film with gelatin (CFG) was validated to be significant. The best casting temperatures for 2 h were 70 and 100 °C among the four tested temperatures (25, 60, 70 and 100 °C). Temperatures did not result in any significant (P ≤ 0.05) differences in any character (color values, TS, water vapor permeability, oxygen transmission, thickness and water activity), except elongation at break. Visually, the CFG had a slightly yellow appearance. The best‐to‐worst order of film stability in the three tested solvents was oil, distilled water (DW) and ethanol. Its stability in ethanol (0–100%), temperature of DW (30–100 °C) and pH (3–7 in DW) demonstrated inverse relationships with the concentration or different conditions, except for pH 8–10 in DW. All treatments were significantly (P ≤ 0.05) different. CONCLUSION: The novel material made from polysaccharides from algae, G. fisheri, was used to improve EF. The edible sachet application is plausible from the EF. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Yellow mustard gum (YMG), which is extracted from the mucilaginous part of yellow mustard bran, has been considered an emerging natural hydrocolloid gum but lacks commercial development and production. To promote the commercial utilization of YMG, this study developed a pilot‐scale YMG production protocol in an economic and environmentally friendly way to produce a clean‐label YMG product. This YMG produced at pilot scale (YMW) was characterized in terms of chemical composition, rheological properties, and interaction with a commercial gum, κ‐carrageenan, and was compared with purified YMG through ethanol precipitation (YME). RESULTS: The protocol processed up to 100 L of raw material with zero solvent and a minimal number of steps and showed strong quasi‐industrial potential. The YMW showed a similar chemical composition as YME. However, the YMW contained a slightly lower amount of carbohydrate and a much larger amount of ash and potassium than the YME. The rheological results concluded that both the YMW and YME solutions exhibited shear‐thinning flow behavior and a weak gel, with YME showing higher viscosity and stronger gel structure. Most interestingly, YMW could form unpourable gels when blended with native κ‐carrageenan whereas YME barely achieved this despite the equivalent total gum concentration. CONCLUSION: This study demonstrated the feasibility of YMG production at a large scale with economic and green procedures and discovered its new functionality for commercial utilization. The gelling ability of YMG could provide it with wider applications as a result of a new potential synergistic combination. All this information should accelerate the process of full commercialization of YMG as a clean‐label functional ingredient. © 2024 His Majesty the King in Right of Canada. Journal of The Science of Food and Agriculture © 2024 Society of Chemical Industry. Reproduced with the permission of the Minister of Agriculture and Agri‐Food Canada. [ABSTRACT FROM AUTHOR]

This study investigated the adsorption of Oxytetracycline (OTC) from pharmaceutical wastewater using a kappa carrageenan based hydrogel (KPB). The aim of the present study was to explore the potential of KPB for long-term pharmaceutical wastewater treatment. A sustainable adsorbent was developed to address oxytetracycline (OTC) contamination. The hydrogel's structural and adsorption characteristics were examined using various techniques like Scanning Electron Microscope (SEM), Fourier Transform Infrared (FTIR), X-ray powder diffraction (XRD), and kinetic models. The results revealed considerable changes in the vibrational modes and adsorption bands of the hydrogel, suggesting the effective functionalization of Bentonite nano-clay. Kappa carrageenan based hydrogel achieved the maximum removal (98.5%) of OTC at concerntration of 40 mg/L, pH 8, cotact time of 140 min and adsorbent dose of 0.1 g (KPB-3). Adsorption of OTC increased up to 99% with increasing initial concentrations. The study achieved 95% adsorption capacity for OTC using a KPB film at a concentration of 20 mg/L and a 0.1 g adsorbent dose within 60 min. It also revealed that chemisorptions processes outperform physical adsorption. The Pseudo-Second-Order model, which emphasized the importance of chemical adsorption in the removal process, is better suited to represent the adsorption behavior. Excellent matches were found that R2 = 0.99 for KPB-3, R2 = 0.984 for KPB-2 and R2 = 0.989 for KPB-1 indicated strong chemical bonding interactions. Statisctical analysis (ANOVA) was performed using SPSS (version 25) and it was found that pH and concentration had significant influence on OTC adsorption by the hydrogel, with p-values less than 0.05. The study identified that a Kappa carrageenan-based hydrogel with bentonite nano-clay and polyvinyl alcohol (PVA) can efficiently remove OTC from pharmaceutical effluent, with a p-value of 0.054, but weak positive linear associations with pH, temperature, and contact time. This research contributed to sustainable wastewater treatment and environmental engineering. [ABSTRACT FROM AUTHOR]

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Copyright of Food & Fermentation Industries is the property of Food & Fermentation Industries and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, physically crosslinked injectable hydrogels based on carrageenan, locust bean gum, and gelatin, and mechanically nano-reinforced with green graphene oxide (GO), were developed to address the challenge of finding materials with a good balance between injectability and mechanical properties. The effect of GO content on the rheological and mechanical properties, injectability, swelling behavior, and biocompatibility of the nanocomposite hydrogels was studied. The hydrogels' morphology, assessed by FE-SEM, showed a homogeneous porous architecture separated by thin walls for all the GO loadings investigated. The rheology measurements evidence that G′ > G″ over the whole frequency range, indicating the dominant elastic nature of the hydrogels and the difference between G′ over G″ depends on the GO content. The GO incorporation into the biopolymer network enhanced the mechanical properties (ca. 20%) without appreciable change in the injectability of the nanocomposite hydrogels, demonstrating the success of the approach described in this work. In addition, the injectable hydrogels with GO loadings ≤0.05% w/v exhibit negligible toxicity for 3T3-L1 fibroblasts. However, it is noted that loadings over 0.25% w/v may affect the cell proliferation rate. Therefore, the nano-reinforced injectable hybrid hydrogels reported here, developed with a fully sustainable approach, have a promising future as potential materials for use in tissue repair. [ABSTRACT FROM AUTHOR]

To further develop a protein-polysaccharide composite fat replacer in low-fat meat products, this used pumpkin seed protein (PSP) and carrageenan to prepare a composite emulsion fat replacer, and added it to myofibrillar protein (MP) to form heat induced gel. The effects of the composite emulsion formed by PSP and carrageenan at various additive amounts on the properties of MP gels were investigated through the determination of gel moisture distribution, textural properties, microstructure, rheological properties, and other indexes. The results showed that when PSP and carrageenan composite emulsion was added at 50%, the water-holding properties and strength of the gel significantly improved (P<0.05), textural properties improved, and cooking loss and freeze-thaw stability significantly reduced (P<0.05). The rheological properties showed that the G' of the gel was always higher than the G". Therefore, a gel structure with elasticity and a denser and homogeneous microstructure was formed. Collectively, the gel properties of MP improved with the addition of 50% PSP and carrageenan composite emulsion. [ABSTRACT FROM AUTHOR]

Copyright of Food & Fermentation Industries is the property of Food & Fermentation Industries and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study addresses concerns related to potential health risks associated with chlorine residues in traditional tea bags, which exhibit resistance to decomposition in soil. Consequently, the study utilized carrageenan, derived from Eucheuma cottonii seaweed, as a coating material for edible film. This research explores the impact of carrageenan concentration and drying temperature on the performance of tea bags. This study applied the randomized complete block design to analyze the impact of three carrageenan concentrations (1%, 3%, and 5%) at three different drying temperatures (80°C, 85°C, and 90°C) on carrageenan-based film. The investigation comprehensively evaluates the compliance of the carrageenan-based film with commercial-grade quality standards through critical factors such as thickness, solubility, mechanical strength and hedonic analysis. The findings indicate that the most effective carrageenan-based edible film can be produced at a concentration of 3% and a drying temperature of 90°C, highlighting its potential as an eco-friendly alternative in tea bag production. [ABSTRACT FROM AUTHOR]

Bougainvillea flower is recognized as food coloring agent due to the presence of betacyanin compounds. The extraction of these compounds is followed by a subsequent process for encapsulation. Therefore, this research aimed to determine the effect of maltodextrin and carrageenan on encapsulation characteristics of bougainvillea flower dye extract and obtain the best ratio. Encapsulation was carried out with the ratio of maltodextrin and carrageenan, namely 10:0 (MC1), 9.5:0.5 (MC2), 9:1 (MC3), 8.5:1.5 (MC4), 8:2 (MC5) and 7.5:2.5 (MC6). The results showed that maltodextrin and carrageenan ratio significantly affected the amendment, moisture content, solubility, brightness level (L*), redness level (a*), yellowness level (b*), total betacyanin, surface betacyanin and encapsulation efficiency. Based on the test, the effectiveness index to produce the best treatment was MC3 with characteristics of amendment, moisture content, solubility, brightness level (L*), redness level (a*), yellowness level (b*), total betacyanin, surface betacyanin and encapsulation efficiency at 91.61 ± 0.34, 6.53 ± 0.22, 87.35 ± 1.90 %, 80.43 ± 1.37, 20.37 ± 0.49, 20.73 ± 0.40, 246.99 ± 2.70, 35.76 ± 0.46 mg/100 g and 85.52 ± 0.09 %, respectively. The encapsulated formulation of bougainvillea flower extract with maltodextrin and carrageenan in a balanced ratio can be used as an alternative to provide natural coloring in food processing. [ABSTRACT FROM AUTHOR]

The viscoelastic behavior of food‐grade biopolymers during gelation has a complex frequency spectrum that is difficult to measure by commercial rheometers. Master curves built by time–temperature superposition (TTS) of data arising from small‐amplitude oscillatory flow (SAOS) or stress relaxation at a given reference temperature can provide the frequency span required to describe the frequency spectrum of highly complex systems such as hydrocolloids (e.g., κappa‐carrageenan). In this work, master curves using TTS were obtained for various concentrations (1%–4% w/w). For a given concentration, mechanical spectra were generated for various temperatures (5, 10, 25, 37, and 45°C) to obtain the master curves and shifting factors (aT, bT) using the WLF (Williams–Landel–Ferry) equation. In this context, a methodology is suggested to obtain a wide observation window to describe complex spectra from gelling systems employed in the chemical industry. Practical applications: The rheological methods used in this work combined the enhancement of the frequency range from experimental stress relaxation and SAOS data with double superposition. These methods are already known, but the combination to achieve an ample frequency range of more than 8 decades represents a useful tool for industrial applications of gelling systems like food hydrocolloids (i.e., κappa‐carrageenan). It also helps to predict the viscoelastic behavior at temperatures and concentrations outside the usual range of rheometric measurements. It is further useful in the areas of equipment design and quality control for food products. [ABSTRACT FROM AUTHOR]

Copyright of Indonesian Fisheries Processing Journal / Jurnal Pengolahan Hasil Perikanan Indonesia is the property of IPB University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to explore the formation mechanism of the emulsion gel induced by high pressure processing (HPP) and its encapsulation and protection of functional ingredients, a curcumin-loaded whey protein isolate (WPI)/κ-carrageenan (κ-CG) composite emulsion gel induced by HPP was prepared. The effect of pressure (400, 500 and 600 MPa), holding time (10, 20 and 30 min) and concentration of κ-CG (0.8%, 1.0% and 1.2%, w/v) on the swelling rate, gel strength, the stability of curcumin in the emulsion gel, water distribution and its mobility, as well as the contents of interface protein were characterized. The results showed that the addition of κ-CG significantly reduced the protein concentration required for the formation of emulsion gel induced by HPP and greatly reduced the swelling rate of the emulsion gel. The gel strength and storage stability of the composite emulsion gels increased with the increase in pressure (400–600 MPa) and holding time (10–30 min). When the pressure increased to 500 MPa, the stability of curcumin in the emulsion gel significantly improved. When the ratio of WPI to κ-CG was 12:1 (the κ-CG concentration was 1.0%), both the photochemical and thermal stability of curcumin were higher than those of the other two ratios. The HPP significantly increased the mobility of monolayer water in the system, while the mobility of multilayer water and immobilized water was significantly reduced. Increasing the holding time and the concentration of κ-CG both can result in an increase in the interfacial protein content in the oil/water system, and the HPP treatment had a significant effect on the composition of the interfacial protein of the emulsion gel. [ABSTRACT FROM AUTHOR]

Carrageenans were widely utilized as thickening and gelling agents in the food and cosmetic industries, and their oligosaccharides have been proven to possess enhanced physicochemical and biological properties. In this study, Shewanella sp. LE8 was utilized for the depolymerization of κ-, ι-, and λ-carrageenan under conditions of fermentation. During a 24-h fermentation at 28 °C, the apparent viscosity of κ-, ι-, and λ-carrageenan decreased by 53.12%, 84.10%, and 59.33%, respectively, accompanied by a decrease in storage modulus, and loss modulus. After a 72-h fermentation, the analysis of methylene blue and molecular weight distribution revealed that ι-carrageenan was extensively depolymerized into smaller polysaccharides by Shewanella sp. LE8, while exhibiting partial degradation on κ- and λ-carrageenan. However, the impact of Shewanella sp. LE8 on total sugars was found to be limited; nevertheless, a significant increase in reduced sugar content was observed. The ESIMS analysis results revealed that the purified components obtained through ι-carrageenan fermentation for 72 h were identified as tetrasaccharides, while the two purified components derived from λ-carrageenan fermentation consisted of a hexasaccharide and a tetrasaccharide, respectively. Overall, the present study first reported the depolymerization of ι-and λ-carrageenan by Shewanella and suggested that the Shewanella could be used to depolymerize multiple carrageenans, as well as complex polysaccharides derived from red algae, to further obtain their oligosaccharides. [ABSTRACT FROM AUTHOR]

The viscoelastic response of carrageenan hydrogels to large amplitude oscillatory shear (LAOS) has not received much attention in the literature in spite of its relevance in industrial application. A set of hybrid carrageenans with differing chemical compositions are gelled in the presence of KCl or NaCl, and their nonlinear viscoelastic responses are systematically compared with mixtures of kappa- and iota-carrageenans of equivalent kappa-carrageenan contents. Two categories of LAOS response are identified: strain softening and strain hardening gels. Strain softening gels show LAOS non-reversibility: when entering the nonlinear viscoelastic regime, the shear storage modulus G′ decreases with increasing strain, and never recovers its linear value G0 after successive LAOS sweeps. In contrast to this, strain hardening carrageenan gels show a certain amount of LAOS reversibility: when entering the nonlinear regime, G′ increases with strain and shows a maximum at strain γH. For strains applied below γH, G0 shows good reversibility and the strain hardening behavior is maintained. For strains larger than γH, G0 decreases significantly indicating an irreversible structural change in the elastic network. Strain hardening and elastic recovery after LAOS prevail for hybrid carrageenan and iota-carrageenan gels, but are only achieved when blends are gelled in NaCl, suggesting a phase separated structure with a certain degree of co-aggregated interface for mixed gels. [ABSTRACT FROM AUTHOR]

In recent decades, renewable and biodegradable polysaccharide-based hydrogels have enjoyed wide applicability among them also as adsorbents for heavy metal removal from wastewaters. Herein we prepared hydrogel beads from iota and kappa carrageenans using a variety of salts as crosslinkers, that were tested for the first time in europium ion (Eu3+) sorption from an aqueous solution as representative lanthanide. The type of the salt, and especially the valance and the hydrated radius of the cation, were found to dictate hydrogel bead formation and structure and, therefore, the Eu3+ sorption yield. The results of ATR-FTIR, SEM and TGA analyses to characterize the iota carrageenan hydrogel beads that were prepared with alkali cations, before and after interaction with Eu3+, indicate that the adsorbent prepared with LiCl was much stiffer and more stable than those prepared with NaCl or KCl. The iota carrageenan beads that were prepared with LiCl were also reused 5 times while exhibiting high adsorption capacities. [ABSTRACT FROM AUTHOR]

[Display omitted] Engineering plant-based microgel particles (MPs) at a molecular scale is meaningful to prepare functional fat analogues. We hypothesize that oat protein isolate (OPI) and κ-carrageenan (CA) have synergy in MPs formation, using MPs with controllable structure, and further to fabricate fat analogues with adjustable characteristics is feasible. Their digestion fate will also be possibly modulated by interfacial coatings. OPI-based conjugated MPs with tunable rigidities by changing crosslinking densities were designed. The relationship between microgel structures, and emulsion gel properties was explored through spectroscopy, microstructure, rheology and tribology. The delivery to lycopene, as well as inhibiting digestion behaviors of fat analogues was evaluated in a simulated gastro-intestinal tract. The rigidity of conjugated MPs could be tailored to optimize the performance of fat analogues. OPI-1 %CA MPs could stabilize emulsions up to 95 % oil fraction with fine texture. Tribological behaviors had a dependence on microgel elasticity and interfacial coatings, medium hard MP-stabilized emulsion was less disrupted without coalescence after oral processing. Digestion was delayed by denser and harder MPs by softening the interfacial particle layer or limiting lipase accessibility. Softer conjugated MPs possessed better flexibility and were broken down more easily leading to a higher rate of lipid digestion. [ABSTRACT FROM AUTHOR]

The research aimed to produce microemulsions loaded with garlic essential oil (5, 10, and 15% w/w) to improve the mechanical and antimicrobial properties of Persian gum and k-carrageenan-based microemulgels against food pathogens. Microemulsions loaded with 10% garlic essential oil had an average particle size of 88.59 ± 2.59 mm and an encapsulation efficiency of 95.61 ± 1.38%. Microemulsions loaded with 10% garlic essential oil with levels of 3, 5, and 7% were used in the structure of hydrogels. Using garlic essential oil microemulsion (up to 50%) in microemulgels structure led to an increase in viscosity and consistency index. The rheological data were well-fitted by the power law model, and all samples had pseudoplastic (shear-thinning) behavior. The mechanical properties of microemulgels were improved by using microemulsions, and a 5% microemulsion of garlic essential oil was associated with an increase in hardness, cohesiveness, and chewiness indices. FTIR analysis confirmed that garlic essential oil is well placed in the microemulsion structure, and microemulsions containing garlic essential oil will strengthen the mechanical properties of microemulgels by establishing hydrogen bonds with the hydrogel matrix. The modeling of the release of garlic essential oil in food simulants showed that the highest amount of release occurs in aqueous media, and the Peleg model is the best description of the release behavior of the essential oil from the structure of microemulgels. The dominant mechanism involved in the garlic essential oil release in the food simulants was the Fickian release mechanism. Staphylococcus aureus showed the highest sensitivity against microemulgels loaded with garlic essential oil. [ABSTRACT FROM AUTHOR]

Summary: This study examined the rheological and textural properties of gels produced through emulsion gelation using pea protein isolate (PPI). Emulsions were prepared with varying PPI concentrations (2%–10%) and 0.25 oil fraction, followed by heat treatment. Higher PPI concentrations improved encapsulation efficiency (EE), but heat slightly reduced it, though EE remained above 90%. Droplet size decreased with higher PPI. The emulsion was then gelled with different kappa‐carrageenan (KC) concentrations (1%–2%) and pH levels (4–7). Gel hardness increased with KC content, while adhesiveness decreased. Springiness, cohesiveness and water‐holding capacity (WHC) rose with pH and KC, while meltability decreased. Rheological tests showed stronger gels with higher KC and lower pH. Storage time generally increased gel strength, except at pH 4. This work highlights the interplay between PPI, KC, pH and storage time in shaping the properties of pea protein‐based emulsions and gels. [ABSTRACT FROM AUTHOR]

Summary: The aim of this study was to investigate the effects of microbial transglutaminase (MTGase) on the textural properties and meltability of vegan cheese formulated using cashew paste, tapioca starch, coconut oil, and pea protein. The parameters were evaluated at various MTGase concentrations (0.1, 0.25, 0.5, 0.75, and 1%) and different incubation times (30, 60, and 90 min). A MTGase concentration of 0.25% resulted in higher meltability Index of 3.02 ± 0.14 and acceptable hardness of 3479.44 ± 14.49 g at 30 min of incubation time. However, prolonged incubation times were found to adversely affect the texture and meltability of the cheese. A similar adverse effect on texture was observed at an MTGase concentration of 0.1% at 60 and 90 min of incubation. The results revealed that lower MTGase concentrations with longer incubation times produced similar effects as higher MTGase concentrations with shorter incubation times. However, at a lower enzyme concentration of 0.1%, meltability was significantly higher (3.24 ± 0.33, P < 0.05) at 60 min of incubation compared to 90 min. The findings suggest that vegan cheese with improved texture, meltability, and sensory properties can be developed by combining cashew, tapioca starch, coconut oil, and pea protein in a ratio of 50:25:20:10, with 1% each of carrageenan and agar, and 60% water, and incubating the mixture with 0.25% MTGase for 30 min at 40 °C. [ABSTRACT FROM AUTHOR]

Summary: This study focuses on encapsulation of sugarcane polyphenols (SPs) to assess its impact on their bioaccessibility and efficacy in inhibiting starch digestion, thereby contributing to glycaemic control strategies. The hypothesis posits that encapsulation enhances both the bioaccessibility and functional effectiveness of SPs. Carboxymethyl cellulose (CMC) and carrageenan (CAR) were employed as encapsulating agents. The methodology included an evaluation of α‐amylase inhibitory activity and the bioaccessibility of SPs across various encapsulation formulations in vitro digestion, highlighting a specific formulation that combines 0.5% CMC and 0.5% CAR to encapsulate 0.4% SPs. Findings reveal that this formulation significantly increases SPs' bioaccessibility and exhibits the highest α‐amylase inhibitory activity, suggesting its potential to support a low glycaemic index (GI) diet (GI = 54.7). It was observed that the GI is significantly inversely correlated with the bioaccessibility of total polyphenols and proanthocyanidins in SPs, while the bioaccessibility of total flavonoids in SPs showed no significant effect on pGI. Interestingly, SPs encapsulated with CMC were less effective in inhibiting starch digestibility than unencapsulated SPs, attributed to the tight binding of CMC with polyphenols, which limits their interaction with starch and α‐amylase. The study highlights the crucial influence of encapsulation materials on polyphenol functionality and emphasises the need for strategic encapsulation in modulating glycaemic responses. These findings advance the understanding of how processing technologies can optimise the health benefits of dietary bioactives, guiding future research towards functional applications and dietary interventions for glycaemic control. [ABSTRACT FROM AUTHOR]

BACKGROUND: The cryoprotective effect of xylooligosaccharide (XO) and kappa‐carrageenan (KC) mixture on silver carp proteins in fluctuated frozen storage from 4 to −18 °C was analyzed. Positive control as a conventional cryoprotectant mixture of sucrose (4%) and sorbitol (4%), KC (3%) and XO/KC (3%) treatments were incorporated in silver carp surimi and myofibrillar proteins to analyze the water mobility and its influence on structural attributes. RESULTS: The temperature fluctuation significantly increased the structural alteration in samples with no treatments due to oxidative changes, protein denaturation and recrystallization. Meanwhile, the mixture of XO and KC (XO/KC 3%) significantly reduced the tertiary and secondary structural alterations by preventing the oxidative changes in α‐helix and tryptophan (Trp) residues. Moreover, XO/KC (3%) inhibited water mobility, hindering the T22 relaxation time, as compared to the samples added with KC (3%) and the positive control. Interestingly, the XO/KC (3%) mixture significantly reduced the formation of extracellular spaces and recrystallization by restricting the partial dehydration of muscles and extracellular solution concentration. CONCLUSION: From the current results, it can be concluded that the XO/KC mixture could be efficient in protecting aquatic food proteins during fluctuating frozen storage by preventing the exposure of Trp residues and α‐helix contents. Moreover, XO/KC restricted the water mobility by establishing a bond and making water unavailable for crystallization and recrystallization. Therefore, XO/KC could be used as an effective mixture to prevent fluctuated and frozen storage changes in aquatic foods. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Objectives. To develop a method to obtain a hydrosol of the salt of chitosan with sulfuric acid—chitosanium sulfate (ChS) hydrosol—and to study the effect of various water-soluble polysaccharides on its stability over time, as well as its resistance to indifferent and non-indifferent electrolytes.Methods. κ-Carrageenan, sodium alginate (SA), and xanthan were used as polymers which perform the function of colloidal protection for ChS nanoparticles. Capillary viscometry was used to study the viscosity of polymer solutions, their molecular weight, and their adsorption on ChS. The stability of the sols over time and their resistance to indifferent and non-indifferent electrolytes were evaluated photometrically. The hydrosol particle size was determined by means of dynamic light scattering.Results. On the surface of ChS, κ-carrageenan is adsorbed most strongly over a wide range of concentrations. The graphs of the dependencies of the relative change in the turbidity of sols with the addition of various polysaccharides on their weight concentration at a sol lifetime of 2 days have the shape of curves with a maximum. Sols with the addition of 0.0125% SA and κ-carrageenan in the range of 0.04% have the greatest stability over time. According to dynamic light scattering data, the average particle size of freshly prepared sols with the addition of the polymers to ensure their greatest stability over time are 10.8 nm and 14.6 nm, respectively. For freshly prepared sols without polysaccharides, this size is 24.8 nm. The hydrosol coagulation threshold with an indifferent electrolyte (NaCl) is 9.3 times higher than that with a non-indifferent electrolyte (Na2SO4). κ-Carrageenan and SA protect the hydrosol from coagulation with an indifferent electrolyte (NaCl) at all their used amounts. At the same polymer concentrations, no protection from coagulation with a non-indifferent electrolyte (Na2SO4) was observed.Conclusions. A method was developed to obtain ChS hydrosol with a positive particle charge. The stability of ChS sols over time was studied both without and with the addition of SA, κ-carrageenan, and xanthan. Sol coagulation thresholds with indifferent and non-indifferent electrolytes, as well as the protective numbers for κ-carrageenan and SA against the coagulation of hydrosols with these electrolytes, were established. The mechanism of stability of sols at certain concentrations of water-soluble polysaccharides was explained using data on the adsorption of these polysaccharides on the surface of chitosan treated with a solution of sulfuric acid. Based on the results of the work, it can be concluded that SA and κ-carrageenan can be used for the efficient stabilization of ChS hydrosols over time and for the colloidal protection of ChS from coagulation with sodium chloride.

This paper is dedicated to the research of phenomena noticed during tests of biodegradable carrageenan-based force and pressure sensors. Peculiar voltage characteristics were noticed during the impact tests. Therefore, the sensors' responses to impact were researched more thoroughly, defining time-dependent sensor output signals from calibrated energy impact. The research was performed using experimental methods when a free-falling steel ball impacted the sensor material to create relatively definable impact energy. The sensor's output signal, which is analogue voltage, was registered using an oscilloscope and transmitted to the PC for further analysis. The obtained results showed a very interesting outcome, where the sensor, which was intended to be piezoresistive, demonstrated a combination of behaviour typical for galvanic cells and piezoelectric material. It provides a stable DC output that is sensitive to the applied statical pressure, and in case of a sudden impact, like a hit, it demonstrates piezoelectric behaviour with some particular effects, which are described in the paper as proton transfer in the sensor-sensitive material. Such phenomena and sensor design are a matter of further development and research. [ABSTRACT FROM AUTHOR]

Biopolymers are polymers of natural origin and are environmentally friendly, carbon neutral and less energy-intense additives that can be used for various geotechnical applications. Biopolymers like xanthan gum, carrageenan, chitosan, agar, gellan gum and gelatin have shown potential for improving subgrade strength, erosion resistance, and as canal liners and in slope stabilization. But minimal research has been carried out on cellulose-based biopolymers, particularly microcrystalline cellulose (MCC), for their application in geotechnical and geo-environmental engineering. In this study, the effect of MCC on select geotechnical properties of kaolin, a weak, highly compressible clay soil, like its liquid and plastic limits, compaction behavior, deformation behavior, unconfined compression strength (UCS) and aging, was investigated. MCC was used in dosages of 0.5, 1.0, 1.5 and 2% of the dry weight of the soil, and the dry mixing method was adopted for sample preparation. The results show that the liquid limit increased marginally by 11% but the plasticity index was nearly 74% higher than that of untreated kaolin. MCC rendered the treated soil stiffer, which is reflected in the deformation modulus, which increased with both dosage and age of the treated sample. The UCS of kaolin increased with dosage and curing period. The maximum UCS was observed for a dosage of 2% MCC at a 90-day curing period. The increase in stiffness and strength of the treated kaolin with aging points out that MCC can be a potential soil stabilizer. [ABSTRACT FROM AUTHOR]

Critical‐size bone defects pose a formidable challenge in clinical treatment, prompting extensive research efforts to address this problem. In this study, an inorganic–organic multifunctional composite hydrogel denoted as PLG‐g‐TA/VEGF/Sr‐BGNPs is developed, engineered for the synergistic management of bone defects. The composite hydrogel demonstrated the capacity for mineralization, hydroxyapatite formation, and gradual release of essential functional ions and vascular endothelial growth factor (VEGF) and also maintained an alkaline microenvironment. The composite hydrogel promoted the proliferation and osteogenic differentiation of rat bone marrow mesenchymal stem cells (rBMSCs), as indicated by increased expression of osteogenesis‐related genes and proteins in vitro. Moreover, the composite hydrogel significantly enhanced the tube‐forming capability of human umbilical vein endothelial cells (HUVECs) and effectively inhibited the process of osteoblastic differentiation of nuclear factor kappa‐B ligand (RANKL)‐induced Raw264.7 cells and osteoclast bone resorption. After the implantation of the composite hydrogel into rat cranial bone defects, the expression of osteogenic and angiogenic biomarkers increased, substantiating its efficacy in promoting bone defect repair in vivo. The commendable attributes of the multifunctional composite hydrogel underscore its pivotal role in expediting hydrogel‐associated bone growth and repairing critical bone defects, positioning it as a promising adjuvant therapy candidate for large‐segment bone defects. [ABSTRACT FROM AUTHOR]

The effects of chia flour and κ-carrageenan on the physicochemical, textural, and sensory properties of reduced-fat chicken patties were investigated. Usage of chia flour decreased pH, while addition of κ-carrageenan increased it. Chicken patties with chia flour had higher thiobarbituric acid reactive substances (TBARS) and lower L*, a*, and b* values. Production stages significantly affected pH, TBARS, and color of the samples (p < 0.01); while pH, TBARS, a*, and b* values increased and L* value decreased after cooking. Adding chia flour and Kappa-carrageenan (κ-carrageenan) to reduced-fat chicken patties increased cooking yield and moisture retention while decreasing the shrinkage. Chia flour and κ-carrageenan increased hardness of samples and the highest mean value was found to be 68.70 ± 1.40 N in the group containing 8% beef fat + 4% chia flour + 5% breadcrumbs + 1% κ-carrageenan. However, adhesiveness and cohesiveness decreased by addition of chia flour and κ-carrageenan. Among the sensory properties, flavor, texture, and general acceptability were significantly affected by the addition of chia flour and κ-carrageenan (p < 0.01). Sensory properties were studied by panelist, and it was found that usage of 2% chia flour and 1% κ-carrageenan in reduced-fat chicken patties could be effective regarding product quality, health benefits, and consumer acceptance. [ABSTRACT FROM AUTHOR]

Flexible ammonia (NH3) gas sensors have gained increasing attention for their potential in medical diagnostics and health monitoring, as they serve as a biomarker for kidney disease. Utilizing the pre-designable and porous properties of covalent organic frameworks (COFs) is an innovative way to address the demand for high-performance NH3 sensing. However, COF particles frequently encounter aggregation, low conductivity, and mechanical rigidity, reducing the effectiveness of portable NH3 detection. To overcome these challenges, we propose a practical approach using polyvinyl alcohol-carrageenan (κPVA) as a template for in the situ growth of two-dimensional COF film and particles to produce a flexible hydrogel gas sensor (COF/κPVA). The synergistic effect of COF and κPVA enhances the gas sensing, water retention, and mechanical properties. The COF/κPVA hydrogel shows a 54.4% response to 1 ppm NH3 with a root mean square error of less than 5% and full recovery compared to the low response and no recovery of bare κPVA. Owing to the dual effects of the COF film and the particles anchoring the water molecules, the COF/κPVA hydrogel remained stable after 70 h in atmospheric conditions, in contrast, the bare κPVA hydrogel was completely dehydrated. Our work might pave the way for highly sensitive hydrogel gas sensors, which have intriguing applications in flexible electronic devices for gas sensing. [ABSTRACT FROM AUTHOR]