Cinnamaldehyde loaded chitosan/tripolyphosphate nanoassemblies: Fabrication, characterization, and in vitro evaluation of antioxidant activity

Polysaccharide film containing cinnamaldehyde-chitosan nanoparticles, a new eco-packaging material effective in meat preservation

The development of novel eco-friendly materials like chitosan for food storage and preservation has become crucial in eliminating plastic packaging and minimizing waste. In this work, cinnamaldehyde has been encapsulated in chitosan nanoparticles and subsequently incorporated into a 2 % chitosan film. The obtained nanoparticles achieved an average radius size of 89.80 nm, PDI of 0.40, and spherical morphology determined by SEM. Cinnamaldehyde was encapsulated in chitosan nanoparticles achieving values of encapsulation close to 7 %, showing a biphasic release profile with sustained release during 5 days. Films with an average thickness of 0.124 mm and elongation at break of 63.66 % to 76.50 % were obtained. Finally, the antimicrobial properties of the films was tested showing reduction values in total aerobic value of 4.85 log cfu/g, total coliform of 1.26 log cfu/g and grow potential value of < 0.5 log10 for Listeria monocitogenes over 20 days.

Cinnamaldehyde-Contained Polymers and Their Biomedical Applications

Cinnamaldehyde, a natural product that can be extracted from a variety of plants of the genus Cinnamomum, exhibits excellent biological activities including antibacterial, antifungal, anti-inflammatory, and anticancer properties. To overcome the disadvantages (e.g., poor water solubility and sensitivity to light) or enhance the advantages (e.g., high reactivity and promoting cellular reactive oxygen species production) of cinnamaldehyde, cinnamaldehyde can be loaded into or conjugated with polymers for sustained or controlled release, thereby prolonging the effective action time of its biological activities. Moreover, when cinnamaldehyde is conjugated with a polymer, it can also introduce environmental responsiveness to the polymer through the form of stimuli-sensitive linkages between its aldehyde group and various functional groups of polymers. The environmental responsiveness provides the great potential of cinnamaldehyde-conjugated polymers for applications in the biomedical field. In this review, the strategies for preparing cinnamaldehyde-contained polymers are summarized and their biomedical applications are also reviewed.

Zingiber officinale essential oil-loaded chitosan-tripolyphosphate nanoparticles: Fabrication, characterization and in-vitro antioxidant and antibacterial activities

Zingiber officinale essential oil (ZEO) was encapsulated in chitosan nanoparticles at different concentrations using the emulsion-ionic gelation technique and its antioxidant and antibacterial effects were investigated. The results indicated that ZEO level had a significant effect on encapsulation efficiency (EE), loading capacity (LC), particle size and zeta potential. The value obtained for EE, LC, mean particle size and zeta potential were 49.11%-68.32%, 21.16%-27.54%, 198.13-318.26 nm and +21.31-43.57 mV, respectively. According to scanning electron micrographs, the nanoparticles had a spherical shape with some invaginations due to the drying process. The presence of essential oil within the chitosan nanoparticles was confirmed by Fourier transform infrared (FTIR) spectroscopy. In vitro release studies in simulated gastrointestinal fluid (SGF) and simulated intestinal fluid (SIF) indicated an initial burst effect followed by slow release with higher release rate in acidic medium of SGF. ZEO-loaded nanoparticles showed DPPH radical scavenging activity of 20%-61% which increased by raising the ZEO level. Moreover, results of antibacterial activity revealed that Staphylococcus aureus (with inhibition zones of 19-35.19 mm2) and Salmonella typhimurium (with inhibition zones of 9.78-17.48 mm2) were the most sensitive and resistant bacteria to ZEO, respectively. Overall, chitosan nanoparticles can be considered as suitable vehicles for ZEO and improve its stability and solubility.

Cinnamaldehyde-Based Self-Nanoemulsion (CA-SNEDDS) Accelerates Wound Healing and Exerts Antimicrobial, Antioxidant, and Anti-Inflammatory Effects in Rats’ Skin Burn Model

Cinnamaldehyde, the main phytoconstituent of the cinnamon oil, has been reported for its potential wound healing activity, associated to its antimicrobial and anti-inflammatory effects. In this study, we are reporting on the cinnamaldehyde-based self-nanoemulsifying drug delivery system (CA-SNEDDS), which was prepared and evaluated for its antimicrobial, antioxidant, anti-inflammatory, and wound healing potential using the rat third-degree skin injury model. The parameters, i.e., skin healing, proinflammatory, and oxidative/antioxidant markers, were evaluated after 3 weeks of treatment regimens with CA-SNEDDS. Twenty rats were divided randomly into negative control (untreated), SNEDDS control, silver sulfadiazine cream positive control (SS), and CA-SNEDDS groups. An aluminum cylinder (120 °C, 10-s duration) was used to induce 3rd-degree skin burns (1-inch square diameter each) on the rat’s dorsum. At the end of the experiment, skin biopsies were collected for biochemical analysis. The significantly reduced wound size in CA-SNEDDS compared to the negative group was observed. CA-SNEDDS-treated and SS-treated groups demonstrated significantly increased antioxidant biomarkers, i.e., superoxide dismutase (SOD) and catalase (CAT), and a significant reduction in the inflammatory marker, i.e., NAP-3, compared to the negative group. Compared to SNEDDS, CA-SNEDDS exhibited a substantial antimicrobial activity against all the tested organisms at the given dosage of 20 µL/disc. Among all the tested microorganisms, MRSA and S. typhimurium were the most susceptible bacteria, with an inhibition zone diameter (IZD) of 17.0 ± 0.3 mm and 19.0 ± 0.9 mm, respectively. CA-SNEDDS also exhibited strong antifungal activity against C. albicans and A. niger, with IZD of 35.0 ± 0.5 mm and 34.0 ± 0.5 mm, respectively. MIC and MBC of CA-SNEDDS for the tested bacteria ranged from 3.125 to 6.25 µL/mL and 6.25 to 12.5 µL/mL, respectively, while the MIC and MBC for C. albicans and A. niger were 1.56 µL/mL and 3.125 µL/mL, respectively. The MBIC and MBEC of CA-SNEDDS were also very significant for the tested bacteria and ranged from 6.25 to 12.5 µL/mL and 12.5 to 25.0 µL/mL, respectively, while the MBIC and MBEC for C. albicans and A. niger were 3.125 µL/mL and 6.25 µL/mL, respectively. Thus, the results indicated that CA-SNEDDS exhibited significant wound healing properties, which appeared to be attributed to the formulation’s antimicrobial, antioxidant, and anti-inflammatory effects.

Eugenol loaded chitosan nanoemulsion for food protection and inhibition of Aflatoxin B1 synthesizing genes based on molecular docking

The present investigation entails the fabrication and characterization of nanometric emulsion of eugenol (Nm-eugenol) encompassed into chitosan for assessing bio-efficacy in terms of in vitro antifungal actions, antiaflatoxigenic potential, and in situ preservative efficacy against Aspergillus flavus infestation and aflatoxin B₁ (AFB₁) mediated loss of dietary minerals, lipid triglycerides and alterations in composition of important macronutrients in stored rice. Nm-eugenol characterized by SEM, XRD, and FTIR exhibited biphasic burst release of eugenol. Reduction in ergosterol and methylglyoxal (AFB₁-inducer) content after Nm-eugenol fumigation depicted biochemical mechanism of antifungal and antiaflatoxigenic activities. In silico 3D homology docking of eugenol with Ver-1 gene validated molecular mechanism of AFB₁ inhibition. Further, significant protection of rice seeds from fungi, AFB₁ contamination and preservation against loss of rice minerals, macronutrients and lipids during storage suggested deployment of chitosan as a biocompatible wall material for eugenol encapsulation and application as novel green preservative for food protection.