The essential oil derived from the bark of Cinnamomum zeylanicum L., Lauraceae, has gained significant attention because of its numerous biological benefits. This study aimed to perform a phytochemical analysis of commercially available Cinnamomum zeylanicum bark essential oil and to evaluate its antioxidant, antimicrobial, immunomodulatory, and antitumor properties. GC–MS analysis was employed to determine the phytochemical composition. The major component of the total essential oil composition was (E)-cinnamaldehyde, constituting 77.93%, followed by eugenol (4.34%), E-caryophyllene (3.68%), and linalool (2.79%). The antioxidant activity was confirmed by DPPH, ABTS, CUPRAC, and TAC assays. In the broth microdilution assay, cinnamon essential oil demonstrated strong antimicrobial activity, with MIC values ranging from 7.37 to 29.50 µg/mL. Furthermore, cinnamon essential oil demonstrated selective antitumor activity by inducing apoptosis and cell-cycle arrest in human colorectal cancer cells (HCT116) while sparing non-cancerous cells (MRC-5). In HCT116 cells, cinnamon essential oil induced apoptosis, downregulated Cyclin D and p-AKT, and caused G1-phase arrest. Additionally, cinnamon essential oil modulated immune responses by reducing pro-inflammatory cytokine production in activated splenocytes and enhancing pro-inflammatory activity in naïve cells. These findings highlight the great potential of the cinnamon bark essential oil in the development of new therapeutic agents.

Microencapsulation technology can be used for the protection of Alpha-tocopherol from degradation in unfavorable environments and enhancement of bioavailability and shelf-life of vitamin E. The aim of this study was the synthesis and characterization of alginate microparticles for the oral delivery of a-tocopherol. Four different formulations of Alpha-tocopherol loaded calcium alginate microparticles for oral delivery were synthesized by external ionotropic gelation method. The vitamin E content in microparticles was 0.5%, 1% and 2% (w/w); the vitamin E/sodium alginate ratio was 1:1 and 1:2. All microparticles were characterized by average particles size, swelling degree, vitamin E content, loading capacity, and encapsulation efficiency. Spherically shaped microparticles with the diameter of 500 to 1000 µm were obtained after the drying process. The size and the swelling degree did not change significantly in 0.1 M HCL, while they were increased in base conditions of phosphate buffer of pH 6.8 and 7.4. Encapsulated vitamin E content was not significantly different between formulations (0.30 ± 0.010 - 0.60 ± 0.021 mg/mL). The loading capacities were in the range between 10 ± 0.11% and 20.45 ± 0.22%, while encapsulation efficiency percentages were between 18.94 ± 0.32% and 31.91 ± 0.41%. The optimum conditions for Alpha-tocopherol encapsulation with the highest percentage of loading capacity and encapsulation efficacy were obtained using 1% sodium alginate, 2% calcium chloride, and vitamin E/polymer in the ratio 1:1. All four formulations showed the expected behavior in different mediums, which simulated gastrointestinal fluids in vivo (0.1 M HCL, phosphate buffer pH 6.8 and pH 7.4): gastroresistance, increasing in the size, and swelling degree in intestinal fluids. This emphasizes the use of alginate microparticles as a carrier for the oral delivery of vitamin E.