Synthesis of Cationic Quaternized Nanolevan Derivative for Small Molecule and Nucleic Acid Delivery.

Levan is a biopolymer composed of fructose chains covalently linked by ß-2,6 glycosidic linkages. This polymer self-assembles into a nanoparticle of uniform size, making it useful for a wide range of applications. Also, levan exhibits various biological activities such as antioxidants, anti-inflammatory, and anti-tumor, that make this polymer very attractive for biomedical application. In this study, levan synthesized from Erwinia tasmaniensis was chemically modified by glycidyl trimethylammonium chloride (GTMAC) to produce cationized nanolevan (QA-levan). The structure of the obtained GTMAC-modified levan was determined by FT-IR, 1H-NMR and elemental (CHN) analyzer. The size of the nanoparticle was calculated using the dynamic light scattering method (DLS). The formation of DNA/QA-levan polyplex was then investigated by gel electrophoresis. The modified levan was able to increase the solubility of quercetin and curcumin by 11-folds and 205-folds, respectively, compared to free compounds. Cytotoxicity of levan and QA-levan was also investigated in HEK293 cells. This finding suggests that GTMAC-modified levan should have a potential application for drug and nucleic acid delivery.

Derivation of MUSIi016-A iPSCs from peripheral blood with blood type O Rh positive.

MUSIi016-A, a human induced pluripotent stem cell (iPSC), generated from peripheral blood mononuclear cells of a healthy blood group O Rh positive donor was reprogrammed using Sendai viral vectors containing Yamanaka's factors. MUSIi016-A iPSC showed pluripotent stem cell characteristics, highly expressed pluripotent markers, and a capacity to differentiate into all three embryonic cell lineages. This iPSC can be used as a model for the generation of blood cells in vitro.

Production and bioactivities of nanoparticulated and ultrasonic-degraded levan generated by Erwinia tasmaniensis levansucrase in human osteosarcoma cells.

Levan is a bioactive polysaccharide that can be synthesized by various microorganisms. In this study, the physicochemical properties and bioactivity of levan synthesized by recombinant levansucrase from Erwinia tasmaniensis were investigated. The synthesis conditions, including the enzyme concentration, substrate concentration, and temperature, were optimized. The obtained levan generally appeared as a cloudy suspension. However, it could transform into a hydrogel at concentrations exceeding 10 % (w/v). Then, ultrasonication was utilized to reduce the molecular weight and increase the bioavailability of levan. Dynamic light scattering (DLS) and gel permeation chromatography (GPC) indicated that the size of levan was significantly decreased by ultrasonication, whereas Fourier transform infrared spectroscopy, 1H-nuclear magnetic resonance, and X-ray powder diffraction revealed that the chemical structure of levan was not changed. Finally, the bioactivities of both levan forms were examined using human osteosarcoma (Saos-2) cells. The result clearly illustrated that sonicated levan had higher antiproliferative activity in Saos-2 cells than original levan. Sonicated levan also activated Toll-like receptor expression at the mRNA level. These findings suggested the important beneficial applications of sonicated levan for the development of cancer therapies.