Effects of Sangju Honey on Oral Squamous Carcinoma Cells.

Since ancient times, honey has been used in traditional medicine owing to its pharmacological effects. It possesses anticancer properties. However, the therapeutic implications of Sangju honey in cancer remains unknown. Therefore, we aimed to demonstrate the potential anticancer effects of Sangju honey on human oral squamous cell carcinoma (OSCC), particularly focusing on epithelial-mesenchymal transition (EMT) and apoptotic and mitogen-activated protein kinase (MAPK) signaling pathways. Ca9-22 and YD-10B human OSCC cells were treated with 0.25% or 0.5% Sangju honey, and the cell viability was examined using the Cell Counting Kit-8 assay. Cell morphology studies were conducted to observe morphological changes, and the wound-healing assay was performed to evaluate the proliferation of honey-treated OSCC cells. Western blot analysis was conducted to investigate protein expression related to EMT and apoptotic and MAPK signaling pathways. Sangju honey reduced cell viability, induced morphological changes, and significantly suppressed the proliferation and migration of Ca9-22 and YD-10B cells. The expression of E-cadherin and N-cadherin was increased and decreased, respectively, in both OSCC cell lines. Moreover, Sangju honey stimulated apoptosis by increasing the expression of p21, p53, cleaved caspase 3, and caspase 9. Furthermore, it downregulated the expression of phospho (p)-extracellular signal-regulated kinases 1 and 2, p-c-Jun amino-terminal kinase, and p-p38 in Ca9-22 and YD-10B cells. Sangju honey inhibits Ca9-22 and YD-10B cell proliferation by regulating EMT, inducing apoptosis, and suppressing the MAPK signaling pathway. Thus, it is a potential anticancer agent for human OSCC.

Metabolic Engineering of Extremophilic Bacterium Deinococcus radiodurans for the Production of the Novel Carotenoid Deinoxanthin.

Deinoxanthin, a xanthophyll derived from Deinococcus species, is a unique organic compound that provides greater antioxidant effects compared to other carotenoids due to its superior scavenging activity against singlet oxygen and hydrogen peroxide. Therefore, it has attracted significant attention as a next-generation organic compound that has great potential as a natural ingredient in a food supplements. Although the microbial identification of deinoxanthin has been identified, mass production has not yet been achieved. Here, we report, for the first time, the development of an engineered extremophilic microorganism, Deinococcus radiodurans strain R1, that is capable of producing deinoxanthin through rational metabolic engineering and process optimization. The genes crtB and dxs were first introduced into the genome to reinforce the metabolic flux towards deinoxanthin. The optimal temperature was then identified through a comparative analysis of the mRNA expression of the two genes, while the carbon source was further optimized to increase deinoxanthin production. The final engineered D. radiodurans strain R1 was able to produce 394 ± 17.6 mg/L (102 ± 11.1 mg/g DCW) of deinoxanthin with a yield of 40.4 ± 1.2 mg/g sucrose and a productivity of 8.4 ± 0.2 mg/L/h from 10 g/L of sucrose. The final engineered strain and the strategies developed in the present study can act as the foundation for the industrial application of extremophilic microorganisms.