ABSTRACT
RESEARCH BACKGROUND: Microbial contamination of food products is one of the significant causes of food spoilage and foodborne illnesses. The use of active packaging films incorporated with antimicrobial agents can be a measure to improve food quality and extend shelf life. Nevertheless, antimicrobial agents such as silver, copper, titanium and zinc in the packaging films have raised concerns among consumers due to toxicity issues. EXPERIMENTAL APPROACH: The current study aims to develop biodegradable gelatine-based edible films incorporated with microcapsules of Clitoria ternatea-derived anthocyanins as a natural antimicrobial agent. The impact of incorporation of microcapsules with anthocyanins on the morphology, thermal, mechanical, water vapour barrier and physicochemical properties of the gelatine films was evaluated in this study. The effectiveness of the developed films against foodborne pathogens and their application for perishable food protection were also investigated. RESULTS AND CONCLUSIONS: The results show that incorporating anthocyanin microcapsules enhances the gelatine film physical and mechanical properties by increasing the thickness, tensile strength, Young's modulus and elongation at break of the films. Scanning electronic microscopy analysis revealed that the film surface morphology with anthocyanin microcapsules had a homogeneous and smooth surface texture compared to the control. The thermogravimetric analysis also showed a slight improvement in the thermal properties of the developed films. Agar well diffusion assay revealed that the developed films exhibit significant inhibition against a broad-spectrum of bacteria. Furthermore, the films composed of gelatine with anthocyanin microcapsules significantly reduced the total viable count of microorganisms in the bean curd during storage for 12 days compared with the control films. NOVELTY AND SCIENTIFIC CONTRIBUTION: Increasing global awareness of healthy and safe food with minimal synthetic ingredients as preservatives has sparked the search for the use of antimicrobial agents of natural origins in active food packaging material. In this study, a safe and effective active packaging film was developed using an environmentally friendly biopolymer, gelatine film incorporated with microcapsules of Clitoria ternatea-derived anthocyanins as a natural antimicrobial agent. This study demonstrated that such a method is not only able to improve the film physical properties but can also significantly prolong the shelf life of food products by protecting them from microbial spoilage.
ABSTRACT
Microbial keratitis is the infection caused by pathogenic microorganisms that commonly occurs among the contact lens users. Various antimicrobial compounds were coated on contact lenses to kill keratitis causing microorganisms, however these compounds caused several adverse side effects. Hence, the aim of this study is to develop a silicone hydrogel contact lens coated with phomopsidione nanoparticle that inhibit keratitis causing clinical isolates. Phomopsidione nanoparticles were synthesized using polyvinyl alcohol as encapsulant. The nanoparticles showed an average size of 77.45â¯nm, with neutral surface charge. Two drug release patterns were observed in the drug release profile, which are the initial slow release phase with extended drug release (release rate 46.65⯵g/h), and the burst release phase observed on Day 2 (release rate 2224.49⯵g/h). This well-regulated drug delivery system enables the control of drug release to meet the therapeutic requirements. On agar diffusion assay, 3 out of 5 test microorganisms were inhibited by phomopsidione nanoparticle coated contact lenses, including two Gram negative bacteria. Besides, all test microorganisms showed at least 99% of growth reduction, with the treatment of the contact lens model. The drug loaded onto the nanoparticles is sufficient to prevent the bacterial growth. In conclusion, this study provides an effective alternative to combat keratitis-causing microorganisms among contact wearers.
