Preparation and Characterization of Natural Material Extracted from Germinated Brown Rice

Purpose: The aim of this study was to prepare and evaluate a natural material extracted from germinated brown rice (GBR). Herein, we evaluated whether the natural material could positively activate the biological effects seen during bone formation, including enhancement of metabolic activity, osteogenesis, and the expression of vascular endothelial growth factor (VEGF), one of the growth factors in human osteoblast-like cells. Methods: The natural material was created by a hot water extraction process after being soaked for 2~3 days in tap water and dried at $50^{\circ}C$. The material was characterized using field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Fourier transformed infrared (FTIR) spectroscopy. The biological behaviors of the material were also investigated; we performed tests to assess cell cytotoxicity, metabolic activity, osteogenic markers related to bone formation, and VEGF. Results: The EDX, XRD, and FTIR results for the natural material indicated the presence of organic compounds. The natural material caused positive increases in cell metabolic activity and mineralized bone formation without cytotoxicity. The protein levels in the extract for the $6.25{\mu}g/mL$, $12.25{\mu}g/mL$, $25{\mu}g/mL$, $50{\mu}g/mL$, and $100{\mu}g/mL$ groups were significantly different from that for the control. Conclusions: The GBR-based natural material was easy to prepare and had characteristics of a potential biomaterial. The biocompatibility of this natural material was evaluated using in vitro techniques; our findings indicate that this novel material is promising for agricultural and biological applications.