A novel green gelatin–agar microencapsulation system with P. urinaria as an improved anti-A. niger model

Current Trends in Gelatin-Based Drug Delivery Systems

Gelatin is a highly versatile natural polymer, which is widely used in healthcare-related sectors due to its advantageous properties, such as biocompatibility, biodegradability, low-cost, and the availability of exposed chemical groups. In the biomedical field, gelatin is used also as a biomaterial for the development of drug delivery systems (DDSs) due to its applicability to several synthesis techniques. In this review, after a brief overview of its chemical and physical properties, the focus is placed on the commonly used techniques for the development of gelatin-based micro- or nano-sized DDSs. We highlight the potential of gelatin as a carrier of many types of bioactive compounds and its ability to tune and control select drugs' release kinetics. The desolvation, nanoprecipitation, coacervation, emulsion, electrospray, and spray drying techniques are described from a methodological and mechanistic point of view, with a careful analysis of the effects of the main variable parameters on the DDSs' properties. Lastly, the outcomes of preclinical and clinical studies involving gelatin-based DDSs are thoroughly discussed.

Development of chitosan-coated agar-gelatin particles for probiotic delivery and targeted release in the gastrointestinal tract

This study reports the development of a novel and simple formulation for probiotic delivery using chitosan-coated agar-gelatin gel particles. This methodology involves the production of agar-gelatin particles by thermally treating a mixture of agar and gelatin solutions at high temperatures (121 °C) and subsequently coating with chitosan. The particles were able to protect the probiotic strain Lactobacillus plantarum NCIMB 8826 during incubation for 2 h in simulated gastric fluid (pH 2), as no statistically significant loss (P > 0.05) in cell concentration was observed, and also resist dissolution in simulated intestinal fluid (pH 7.2). Interestingly, this protection is related to the fact that the intense thermal treatment affected the physicochemical properties of agars and resulted in the formation of a strong and tight polymer network, as indicated by the X-ray diffraction (XRD) analysis. Using an in vitro faecal batch fermentation model simulating the conditions of the distal part of the large intestine (pH 6.7–6.9), it was demonstrated by quantitative real-time PCR that the majority of L. plantarum cells were released from the agar-gelatin particles within 30 to 48 h. Overall, this work led to the development of a novel methodology for the production of probiotic-containing particles, which is simpler compared with current encapsulation technologies and has a lot of potential to be used for the controlled release of probiotics and potentially other solid bioactives in the large intestine.

Key Points

• Chitosan gel particles is a simple and scalable method of probiotic encapsulation.

• Autoclaving agar-gelatin particles increases their stability at low pH.

• Chitosan gel particles protected L. plantarum during gastrointestinal conditions.

• Probiotics could be controlled release in the colon using chitosan gel particles.

Fabrication and characterization of soluble soybean polysaccharide and nanorod-rich ZnO bionanocomposite

In this study, a novel bionanocomposite film was prepared by the casting method. Different concentrations [i.e., 0%, 1%, 2%, and 4% (w/w)] of nanorod-rich ZnO (ZnO-nr) were incorporated into soluble soybean polysaccharide (SSPS). The mechanical, thermophysical, antimicrobial, and barrier properties of the resultant bionanocomposite films were evaluated. Incorporation of 4% ZnO-nr into the SSPS matrix reduced water vapor permeability from 8.19×10(-11) to 5.25×10(-11) (gm(-1)s(-1)Pa(-1)) and oxygen permeability from 223 to 127(cm(3)μmm(-2)day(-1)atm(-1)). The elongation at break and heat seal strength of the films increased by over 20%. The moisture content, glass transition temperature, and tensile strength of the SSPS films significantly decreased by ZnO-nr incorporation. SSPS/ZnO-nr (4%) films showed 0% UV transmittance and were able to absorb over 70% of the near-infrared spectrum. The SSPS/ZnO-nr films exhibited excellent antimicrobial activity against Escherichia coli and Staphylococcus aureus. In summary, ZnO-nr is an excellent potential filler for SSPS-based films used as packaging materials.

Functional, thermal, and antimicrobial properties of soluble soybean polysaccharide biocomposites reinforced by nano TiO2

This study describes a new polysaccharide-based bionanocomposite developed through solvent casting. Different concentrations (i.e., 0%, 1%, 3%, and 5% (w/w)) of nano titanium dioxide (TiO2-N) were incorporated into soluble soybean polysaccharide (SSPS), and the functional properties of the resultant SSPS films were estimated. Incorporation of TiO2-N into the SSPS matrix decreased water vapor permeability from 7.41 to 4.44 × (10(-11)gm(-1) s(-1) Pa(-1)) and oxygen permeability from 202 to 98 (cm(3)μmm(-2) d(-1) atm(-1)). Moisture content also decreased, the glass transition temperature increased, and the mechanical properties and heat seal strength of the SSPS films improved. SSPS bionanocomposite films showed excellent antimicrobial activity against Escherichia coli and Staphylococcus aureus. In summary, TiO2-N shows potential use as a filler in SSPS-based films for the food and non-food industries.

Preparation and characterization of novel bionanocomposite based on soluble soybean polysaccharide and halloysite nanoclay

In this research, casting method was used to prepare novel polysaccharide-based bio-nanocomposite films with halloysite nanoclay (HNC). HNC was incorporated into soluble soybean polysaccharide (SSPS) at different concentrations (e.g., 1, 3, and 5%, w/w). Functional properties of SSPS films were evaluated following by ASTM standards. Incorporating HNC to SSPS matrix decreased water vapor permeability from 7.41 × 10(-11) to 3.27 × 10(-11) (gm(-1) s(-1) Pa(-1)) and oxygen permeability from 202 to 84 cm(3)(μm m(-2) day(-1) atm(-1)). By addition of HNC to SSPS films, glass transition temperature, tensile strength, and heat seal strength was increased and elongation at break was decreased. Uniform and smooth surface morphology revealed by scanning electron microscopy and shows no sign of phase separation among the film constitutes. In summary, HNC has the potential to be a filler in SSPS-based films for use in food and non-food packaging industries.

The Effects of Nano-SiO2 on Mechanical, Barrier, and Moisture Sorption Isotherm Models of Novel Soluble Soybean Polysaccharide Films

In this research, a novel polysaccharide-based bionanocomposite film was prepared via dispersion casting method. Nano-silicon dioxide (SiO2-N) was incorporated into soluble soybean polysaccharide (SSPS) at different concentrations (i.e., 0%, 1%, 3%, and 5% w/w dried SSPS). Mechanical (tensile strength, elongation at break, and Young’s modulus), physical (moisture content, water solubility, and moisture uptake), and barrier properties of bionanocomposite films were evaluated. Incorporation of 5% SiO2-N to SSPS matrix decreased water vapor permeability (WVP) from 7.96×10−11 to 4.75×10−11 g m−1 s−1 Pa−1 and oxygen permeability from 215 to 96 cm3 µm m−2 day−1 atm−1. Heat seal strength and mechanical properties of SSPS films were improved. Moisture sorption isotherm of SSPS films supported by SiO2-N was shifted to lower moisture content, and monolayer moisture content of the films decreased significantly (p<0.05). In summary, SiO2-N is a potential filler in SSPS-based films for packaging materials.

A review of the preparation and application of flavour and essential oils microcapsules based on complex coacervation technology

This paper briefly introduces the preparation and application of flavour and essential oils microcapsules based on complex coacervation technology. The conventional encapsulating agents of oppositely charged proteins and polysaccharides that are used for microencapsulation of flavours and essential oils are reviewed along with the recent advances in complex coacervation methods. Proteins extracted from animal-derived products (gelatin, whey proteins, silk fibroin) and from vegetables (soy proteins, pea proteins), and polysaccharides such as gum Arabic, pectin, chitosan, agar, alginate, carrageenan and sodium carboxymethyl cellulose are described in depth. In recent decades, flavour and essential oils microcapsules have found numerous potential practical applications in food, textiles, agriculturals and pharmaceuticals. In this paper, the different coating materials and their application are discussed in detail. Consequently, the information obtained allows criteria to be established for selecting a method for the preparation of microcapsules according to their advantages, limitations and behaviours as carriers of flavours and essential oils.