Preparation of biodegradable xanthan-glycerol hydrogel, foam, film, aerogel and xerogel at room temperature

Structural and Physiochemical Properties of Polyvinyl Alcohol-Succinoglycan Biodegradable Films

Polyvinyl alcohol (PVA)-bacterial succinoglycan (SG) biodegradable films were developed through a solvent-casting method. Effects of the PVA/SG ratio on the thickness, transmittance, water holding capacity, and structural and mechanical properties were investigated by various analytical methods. All the prepared films were transparent and uniform, and XRD and FTIR analyses confirmed that PVA was successfully incorporated into SG. The films also showed excellent UV-blocking ability: up to close to 80% with increasing SG concentration. The formation of effective intermolecular interactions between these polymers was evidenced by their high tensile strength and moisture transport capacity. By measuring the biodegradation rate, it was confirmed that films with high SG content showed the fastest biodegradation rate over 5 days. These results confirm that PVA/SG films are eco-friendly, with both excellent biodegradability and effective UV-blocking ability, suggesting the possibility of industrial applications as a packaging material in various fields in the future.

Effect of polyvinyl alcohol and carboxymethylcellulose on the technological properties of fish gelatin films

The objective of this work was to develop biodegradable films by mixing gelatin/carboxymethylcellulose (FG/CMC) and gelatin/polyvinyl alcohol (FG/PVOH) and to evaluate the effect of adding these polymers on the properties of fish gelatin films. The films FG/CMC and FG/PVOH were produced in the proportions 90/10, 80/20 and 70/30 and characterized their physical, chemical and functional properties. The addition of CMC and PVOH improved the mechanical strength, barrier property and water solubility of gelatin films. FG/CMC films showed greater tensile strength and greater solubility than FG/PVOH. The maximum concentration of CMC promoted the highest mechanical resistance, while the highest PVOH content produced the film with the lowest solubility. The proposed mixing systems proved to be adequate to improve the properties of fish gelatin films, with potential for application in the packaging sector.

Insights into the Role of Biopolymer-Based Xerogels in Biomedical Applications

Xerogels are advanced, functional, porous materials consisting of ambient, dried, cross-linked polymeric networks. They possess characteristics such as high porosity, great surface area, and an affordable preparation route; they can be prepared from several organic and inorganic precursors for numerous applications. Owing to their desired properties, these materials were found to be suitable for several medical and biomedical applications; the high drug-loading capacity of xerogels and their ability to maintain sustained drug release make them highly desirable for drug delivery applications. As biopolymers and chemical-free materials, they have been also utilized in tissue engineering and regenerative medicine due to their high biocompatibility, non-immunogenicity, and non-cytotoxicity. Biopolymers have the ability to interact, cross-link, and/or trap several active agents, such as antibiotic or natural antimicrobial substances, which is useful in wound dressing and healing applications, and they can also be used to trap antibodies, enzymes, and cells for biosensing and monitoring applications. This review presents, for the first time, an introduction to biopolymeric xerogels, their fabrication approach, and their properties. We present the biological properties that make these materials suitable for many biomedical applications and discuss the most recent works regarding their applications, including drug delivery, wound healing and dressing, tissue scaffolding, and biosensing.

Use of xanthan gum for whole cell immobilization and its impact in bioremediation - a review

Xanthan gum is one of the exo-polysaccharides produced by bacteria and is characterized by unique non-Newtonian properties. Its structure and conformation strongly depend on the fermentation conditions and such factors as temperature and ions concentration. The properties of the xanthan gum were appreciated in the controlled drug delivery but in the crosslinked form. Due to its ability to enhance the survival rate of immobilized bacteria, the potential of a crosslinked form is promising. Unfortunately, xanthan gum crosslinking procedures often require toxic substances or harsh environmental conditions, which cannot be used in the entrapment of living cells. In this study, we summarised a crosslinking method that could potentially be modified to reduce its toxicity to living cells. Moreover, this review also includes using xanthan gum in bioremediation studies and possible utilization methods to avoid carrier accumulation in the environment.

A Review on Revolutionary Natural Biopolymer-Based Aerogels for Antibacterial Delivery

A biopolymer-based aerogel has been developed to become one of the most potentially utilized materials in different biomedical applications. The biopolymer-based aerogel has unique physical, chemical, and mechanical properties and these properties are used in tissue engineering, biosensing, diagnostic, medical implant and drug delivery applications. Biocompatible and non-toxic biopolymers such as chitosan, cellulose and alginates have been used to deliver antibiotics, plants extract, essential oils and metallic nanoparticles. Antibacterial aerogels have been used in superficial and chronic wound healing as dressing sheets. This review critically analyses the utilization of biopolymer-based aerogels in antibacterial delivery. The analysis shows the relationship between their properties and their applications in the wound healing process. Furthermore, highlights of the potentials, challenges and proposition of the application of biopolymer-based aerogels is explored.

Saponin foam for soil remediation: On the use of polymer or solid particles to enhance foam resistance against oil

Foams can be used to remediate aquifer pollution due to industrial leaks. However, when in contact with oily pollutants, foams may collapse and thus have a very limited life-time. A suitable formulation of biodegradable foam that resists oil contact is therefore needed. Hence, the ability of xanthan polymer and silica colloidal particles to stabilise foam against oil was investigated. Their performance in terms of stabilisation was evaluated via foam generation experiments in columns of porous medium, conducted with and without oil. The results show that the addition of xanthan polymer led to an increase in the viscosity of the solution, which thwarted the formation of foam. It did not improve the resistance of foam to oil, but increased altogether the resistance factor up to more than twice the original value. Concerning silica particles, it was demonstrated that they both noticeably increased resistance factor and moderately stabilised foam against oil by 20% at optimum concentration. As such, this study presents a new way to reinforce foam against oil for soil remediation issues.

Eminence of Microbial Products in Cosmetic Industry

Cosmetology is the developing branch of science, having direct impact on the society. The cosmetic sector is interested in finding novel biological alternatives which can enhance the product attributes as well as it can substitute chemical compounds. Many of the compounds are having biological origin and are acquire from bacteria, fungi, and algae. A range of biological compounds, like bio-surfactant, vitamins, antioxidants, pigments, enzymes, peptides have promising features and beneficial properties. Moreover, these products can be produced commercially with ease. The review will encompass the importance and use of microbial compounds for new cosmetic formulations as well as products associated with it.

Formation of Nanofibrous Structure in Biopolymer Aerogel during Supercritical CO2 Processing: The Case of Chitosan Aerogel

Supercritical drying is widely considered as the gold standard to produce aerogels that preserve the microstructure of the gels, but we have found this is not always the case. Chitosan aerogel, one of the emerging biopolymer aerogels, was prepared by chemical cross-linking gelation, followed by solvent exchange with methanol and supercritical drying using CO₂. Small-angle X-ray scattering analysis shows that the structure of the wet gel, which consists of Gaussian chains of individual molecular strands, converts into a nanofibrous network during CO₂ processing. In situ observation reveals a drastic shrinkage of the gel in CO₂, demonstrating that physical coagulation caused by the low affinity between chitosan and CO₂ is the main structure-forming step. These results challenge the common perception of supercritical drying: it is no longer an inactive drying method, but rather an active nanostructure forming a tool to produce porous biopolymer materials with tailored structure and properties.