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To study the effects of hot air temperature and slice thickness on the drying characteristics, physicochemical properties and antioxidant components of Mulusasiatica Nakai slices. The Mulusasiatica Nakai slices with thickness of 3 mm and 5 mm were dried in the hot air temperature range of 60, 70, 80, 90 ℃. Five classical food thin layer drying models were used to nonlinear fit the experimental data, and the diffusion coefficient and activation energy were calculated. The color, hardness, rehydration properties and antioxidant components of the dried slices were analyzed. Results showed that, the drying time was obviously shortened with the increase of hot-air temperature and the decrease of slice thickness. In the experimental drying temperature range, the effective diffusion coefficient increased with the increase of temperature. The activation energies were 17.46 kJ/mol and 23.82 kJ/mol when the slice thickness was 3 and 5 mm, respectively. Fick diffusion model was used to describe the evaporation process of Mulusasiatica Nakai slices. Compared with other models, Page model could better fit the drying process of Mulusasiatica Nakai slices. When the slice thickness was 3 mm and the hot-air temperature was 90 ℃, the dried product was light yellow, with high rehydration performance and low hardness. In terms of antioxidant retention, heat lost about 50% of ascorbic acid, but only about 35% of total phenolics. In conclusion, the slice thickness could be selected to be 3mm, the hot air temperature 90 ℃ for drying, drying time 90 min, dried product color was light yellow, higher rehydration performance, lower hardness, and could better retain the antioxidant components in Mulusasiatica Nakai.

This study was to investigate the potential mechanisms of treatment with metformin (Met) combined with kaempferol (Kae) against postmenopausal osteoporosis. Experiments were conducted in both ovariectomy (OVX)-induced osteoporosis rats and in vitro using RAW264.7 cells, MC3T3-E1 cells, and HUVECs. Results demonstrated the therapeutic effect of Met combined with Kae on osteoporosis. In vivo, Kae alone and in combination with Met treatments enhanced tibial trabecular microstructure, bone mineral density (BMD), and mechanical properties in OVX rats without causing hepatotoxicity and nephrotoxicity. It also reduced bone resorption markers (CTX-1 and TRAP) and increased the bone formation marker (PINP) level in the serum of OVX rats. The expression of bone resorption marker TRAP was reduced, while bone formation markers Runx2 and ALP were enhanced in the bone tissue of OVX rats. Furthermore, Met combined with Kae also promoted the expression of angiogenesis-related markers CD31 and VEGF in OVX rats. In vitro, MC3T3-E1s cells treated with Met combined with Kae showed higher expression of ALP, Runx2, and VEGF. Interestingly, the treatment did not directly promote HUVECs migration and angiogenesis, but enhanced osteoblast-mediated angiogenesis by upregulating VEGF levels. Additionally, Met combined with Kae treatment promoted VEGF secretion in MC3T3-E1, and activated the Notch intracelluar pathway by upregulating HES1 and HEY1 in HUVECs. Meantime, their stimulation on CD31 expression were inhibited by DAPT, a Notch signaling inhibitor. Overall, this study demonstrates the positive effects of Met combined with Kae on osteoporotic rats by promoting osteogenesis-angiogenesis coupling, suggesting their potential application in postmenopausal osteoporosis.

This present work investigated the influence of black rice anthocyanins as antioxidants on the oxidation stability of oil. Malonic acid, succinic acid and succinic anhydride were grafted on black rice anthocyanins through acylation method to improve their antioxidant activity in oil. The results from fourier transform infrared spectroscopy (FTIR) showed new absorption peaks near 1744 cm-1 and 1514 cm-1, which implied that malonic acid, succinic acid and succinic anhydride grafted on the -OH of glucoside and rutinoside through esterification reaction and resulted that the polarity of these were reduced. Total content of anthocyanin (TAC) decreased to 166. 3 mg/g, 163.7 mg/g and 150.2 mg/g, respectively after modification with succinic acid, malonic acid and succinic anhydride. Compared with native anthocyanins, the acylation of black rice anthocyanins partially reduced its antioxidant activity. In addition, DPPH clearance of molecular modified anthocyanins decreased to 62.6% (San-An). As revealed in the oil stability through the determination of primary oxidation products (PV) and secondary oxidation products (p-AV), Sa-An, Ma-An and San-An showed stronger antioxidant activity in Schaal oven accelerated oxidation test during 12 days than native black rice anthocyanin in both corn oil and flaxseed oil. Molecular modified black rice anthocyanins are expected to be used as colorants, antioxidants, etc. in oil-rich food. [ABSTRACT FROM AUTHOR]