PVA/Inulin-Based Sustainable Films Reinforced with Pickering Emulsion of Niaouli Essential Oil for Potential Wound Healing Applications

Abstract

In this study, sustainable water-based films were produced via the solvent-casting method. Petroleum-free-based polyvinyl alcohol (PVA) and carbohydrate-based inulin (INL) were used as matrices. Vegetable-waste pumpkin powder was used in the study because of its sustainability and antibacterial properties. Pickering emulsions were prepared using β-cyclodextrin. The influence of the different ratios of the β-cyclodextrin/niaouli essential oil (β-CD/NEO) inclusion complex (such as 1:1, 1:3, and 1:5) on the morphological (SEM), thermal (TGA), physical (FT-IR), wettability (contact angle), and mechanical (tensile test) characteristics of PVA/inulin films were investigated. Moreover, the antibacterial activities against the Gram (−) (Escherichia coli and Pseudomonas aeruginosa) and Gram (+) (Staphylococcus aureus) bacteria of the obtained films were studied. From the morphological analysis, good emulsion stability and porosity were obtained in the Pickering films with the highest oil content, while instability was observed in the Pickering films with the lowest concentration of oil content. Thermal and spectroscopic analysis indicated there was no significant difference between the Pickering emulsion films and neat films. With the addition of Pickering emulsions, the tensile stress values decreased from 7.3 ± 1.9 MPa to 3.3 ± 0.2. According to the antibacterial efficiency results, films containing pumpkin powder and Pickering emulsion films containing both pumpkin powder and a ratio of 1:1 (β-CD/NEO) did not have an antibacterial effect, while Pickering emulsion films with a ratio of (β-CD/NEO) 1:3 and 1:5 showed an antibacterial effect against Escherichia coli, with a zone diameter of 12 cm and 17 cm, respectively. Among the samples, the films with ratio of (β-CD/NEO) 1:5 had the highest antioxidant capacity, as assessed by DPPH radical scavenging at 12 h intervals. Further, none of the samples showed any cytotoxic effects the according to LDH and WST-1 cytotoxicity analysis for the NIH3T3 cell line. Ultimately, it is expected that these films are completely bio-based and may be potential candidates for use in wound healing applications.

Pickering emulsion: From controllable fabrication to biomedical application

“…Although there was no significant difference in wound healing rates between the curcumin group and the Pickering emulsion group after 14 days, the latter promoted high storage in the stratum corneum and slowly released the drug to deeper layers of the skin. In addition, other compoents of Pickering emulsion also exerted therapetuic effect 112,113 . Bao et al.…”

“…In addition, other compoents of Pickering emulsion also exerted therapetuic effect. 112,113 Bao et al developed a Pickering emulsion composed of chitosan nanoparticles, tea tree oil and curcumin. The tea tree oil contained in the Pickering emulsion could be sustained to release and further strengthen its antibacterial activity toward several bacteria.…”

Rheological and Micro-Rheological Properties of Chicory Inulin Gels

“…Inulin has also been used as a drug stabilizer in pharmaceutical formulations, as a modifier and/or carrier for drug delivery, and as a diagnostic/therapy agent for diseases [ 4 ]. There is a report recently indicating that inulin-based films can be used as wound healing materials [ 5 ]. Wound healing materials would be biocompatible with the human body and have a soft consistency with a high water content.…”

“…And wound healing gels provide mechanical support and adhesion sites for cells in the living body and give mechanical strength and structural integrity to tissues and organisms [ 6 , 7 , 8 ]. Inulin’s biological nature, gel formation with high water content, and soft consistency make inulin gel a good candidate for wound healing material [ 5 ]. Moreover, inulin has many applications in the food industry as a fat replacer and a substitute for starch [ 9 ].…”

“…When inulin is dispersed into water, it forms a white creamy three-dimensional gel network composed of sub-micron particles [ 5 , 10 ]. The resulting inulin gels are stable in acidic and high-temperature conditions and provide interesting opportunities to modify rheological properties in food and nonfood applications.…”