Effects of gellan gum and inulin on mixed-gel properties and molecular structure of gelatin

Effect of tremella polysaccharides on the quality of collagen jelly: insight into the improvement of the gel properties and the antioxidant activity of yak skin gelatin

BACKGROUND

The present study aimed to investigate the effects of tremella polysaccharides on the gel properties and antioxidant activity of yak skin gelatin with a view to improving the quality of collagen jellies. The preparation of composite gels were performed by yak skin gelatin (66.7 mg mL-1) and tremella polysaccharides with different concentrations (0, 2, 4, 6, 8 mg mL-1), and finally the collagen jelly was prepared by composite gel (yak skin gelatin: 66.7 mg mL-1; tremella polysaccharides:6 mg mL-1) with the best performance.

RESULTS

Tremella polysaccharides not only improved the hardness, springiness, gel strength, water holding capacity and melting temperature of yak skin gelatin, but also enhanced the composite gel's scavenging activity against ABTS radicals, DPPH radicals, O2 and OH radicals. The filling of tremella polysaccharides into the gelatin network increased the number of crosslinking sites inside the gel, which resulted in the gel network structure becoming dense and orderly. The gel particles became finer and more uniform, and the thermal stability was improved. Furthermore, the sensory score of commercially available gelatin jelly decreased more rapidly during storage compared to the composite gel jelly.

CONCLUSION

The gel properties and antioxidant activity of yak skin gelatin were improved by adding tremella polysaccharides, and then the quality and storage properties of the jelly were improved, which also provided technical reference for the development of functional gel food. © 2024 Society of Chemical Industry.

Gel properties and interactions of hydrogels constructed with low acyl gellan gum and puerarin

To develop composite hydrogels based on low acyl gellan gum (GG), the effect of puerarin (PUE) on the gel properties of GG was investigated. The results showed that the maximum storage modulus (G') of the 1.2 % GG/0.8 % PUE composite hydrogel was 377.4 Pa at 0.1 Hz, which was enhanced by 4.7-fold compared with that of 1.2 % GG. The melting temperature of this composite hydrogel increased from 74.1 °C to >80.0 °C. LF-NMR results showed that a significant amount of free water was present in the hydrogel matrix. The surface structure aggregation and the shrinkage of the honeycomb meshes in the composite hydrogel proved the cross-linking of PUE and GG. XRD, FTIR and molecular simulation results illustrated that hydrogen bonds were the most important factor controlling the interaction between GG and PUE. Thus, the GG/PUE composite hydrogel has good elasticity, thermal stability and water retention, which lays a good foundation for further application in the food industry.

Development of alkaline-stable nanoformulation of nisin: special insights through cytotoxic and antibacterial studies

Nisin, a thermostable, approved food preservative, has limited therapeutic applications because of its high pH and proteolytic enzyme instability. The unavailability of a rapid, simple method of detection also restricts the research of nisin. The objective of this study was to adapt the simple, rapid protein estimation method of detection for nisin formulation and to formulate and evaluate site-specific nanoformulation for therapeutic applications, viz. colon cancer, and anti-bacterial action. Three nanoformulations of nisin with chitosan, gellan gum, and dextran (ECN, EGN, and EDN) were prepared and characterized in vitro. Among three, EGN was selected as a good formulation based on its size surface charge, morphology, drug loading, and release characteristics. FT-IR and DSC revealed the interaction pattern and stability nature. The stability of nisin in an alkaline environment was confirmed by CD. Its therapeutic applications were proved by efficiency against colon cancer cells evaluated by MTT assay and AO/EB staining using Caco-2 cell lines. The in situ sol-gel mechanism imparted by gellan gum was proved the sole reason for the stability and activity of nisin in EGN at lower GIT. This was confirmed (using rheometer) by shear-thickening characteristics of formulation EGN in simulated colon fluid. The antibacterial activity against Staphylococcus aureus by disk diffusion method was also performed to confirm the retention of antimicrobial activity of nisin in EGN. Hence, gellan gum-nisin colloidal nanoparticles are found good candidates for drug delivery at lower GIT and stabilizing alkaline food materials.

Influence of Different pH Values on Gels Produced from Tea Polyphenols and Low Acyl Gellan Gum

To explore the influence of pH values on the properties of a compound system containing tea polyphenols (TPs) and low acyl gellan gum (LGG), the color, texture characteristics, rheological properties, water holding capacity (WHC), and microstructure of the compound system were measured. The results showed that the pH value noticeably affects the color and WHC of compound gels. Gels from pH 3 to 5 were yellow, gels from pH 6 to 7 were light brown, and gels from pH 8 to 9 were dark brown. The hardness decreased and the springiness increased with an increase in pH. The steady shear results showed that the viscosity of the compound gel solutions with different pH values decreased with increasing shear rates, indicating that all of the compound gel solutions were pseudoplastic fluids. The dynamic frequency results showed that the G' and G″ of the compound gel solutions gradually decreased with increasing pH and that G' was higher than G″. No phase transition occurred in the gel state under heating or cooling conditions at pH 3, indicating that the pH 3 compound gel solution was elastic. The WHC of the pH 3 compound gel was only 79.97% but the WHC of compound gels pH 6 and pH 7 was almost 100%. The network structure of the gels was dense and stable under acidic conditions. The electrostatic repulsion between the carboxyl groups was shielded by H⁺ with increasing acidity. The three-dimensional network structure was easily formed by an increase in the interactions of the hydrogen bonds.

3D printed MCT oleogel as a co-delivery carrier for curcumin and resveratrol

Designing a suitable matrix to protect sensitive bioactive compounds is an important stage in nutraceutical development. In this study, emulsion templated medium-chain triglycerides (MCT) oleogel was developed as co-delivery carriers for synergistic nutraceuticals, curcumin, and resveratrol and to 3D print in customized shapes for personalized nutrition. To obtain the stable emulsion, gelatin and gellan gum were added such that their protein-polysaccharide interaction helps in the structuring of the oil phase. Increasing the amount of gellan gum had a positive effect on stabilizing the emulsion but became the critical parameter during 3D printing. Hence, gellan gum of 1.5% (w/v) and gelatin at 10% (w/v) of water were considered optimum to produce a stable 30% O/W emulsion for 3D printing. Upon analyzing the in-vitro digestion behavior of the oleogel, it was observed that the bioactives were protected under oral and gastric conditions and allowed intestinal targeted delivery. The total bioaccessible fraction increased up to 1.13-fold and 1.2-fold for curcumin and resveratrol respectively compared to control (MCT oil). The FFAs release profile also indicated that gelators play an important role in lipase activity. Also, the ex-vivo everted gut sac analysis showed enhanced permeation of about 1.83 times and 1.13 times for curcumin and resveratrol respectively. Thus, this study provides useful insights into the 3D printing of emulsion templated oleogel as personalized nutraceutical carriers.

Current advances in cell therapeutics: A biomacromolecules application perspective

INTRODUCTION

Many chronic diseases have evolved and to circumvent the limitations of using conventional drug therapies, smart cell encapsulating delivery systems have been explored to customize the treatment with alignment to disease longevity. Cell therapeutics has advanced in tandem with improvements in biomaterials that can suitably deliver therapeutic cells to achieve targeted therapy. Among the promising biomacromolecules for cell delivery are those that share bio-relevant architecture with the extracellular matrix and display extraordinary compatibility in the presence of therapeutic cells. Interestingly, many biomacromolecules that fulfil these tenets occur naturally and can form hydrogels.

AREAS COVERED

This review provides a concise incursion into the paradigm shift to cell therapeutics using biomacromolecules. Advances in the design and use of biomacromolecules to assemble smart therapeutic cell carriers is discussed in light of their pivotal role in enhancing cell encapsulation and delivery. In addition, the principles that govern the application of cell therapeutics in diabetes, neuronal disorders, cancers and cardiovascular disease are outlined.

EXPERT OPINION

Cell therapeutics promises to revolutionize the treatment of various secretory cell dysfunctions. Current and future advances in designing functional biomacromolecules will be critical to ensure that optimal delivery of therapeutic cells is achieved with desired biosafety and potency.

Inulin and Its Application in Drug Delivery

Inulin’s unique and flexible structure, stabilization/protective effects, and organ targeting ability make it an excellent drug delivery carrier compared to other biodegradable polysaccharides. The three hydroxyl groups attached to each fructose unit serve as an anchor for chemical modification. This, in turn, helps in increasing bioavailability, improving cellular uptake, and achieving targeted, sustained, and controlled release of drugs and biomolecules. This review focuses on the various types of inulin drug delivery systems such as hydrogel, conjugates, nanoparticles, microparticles, micelles, liposomes, complexes, prodrugs, and solid dispersion. The preparation and applications of the different inulin drug delivery systems are further discussed. This work highlights the fact that modification of inulin allows the use of this polymer as multifunctional scaffolds for different drug delivery systems.