National Engineering Research Center of JUNCAO Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China; College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China.
National Engineering Research Center of JUNCAO Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China.
Int J Biol Macromol. 2019 Jun 15;131:81-88. doi: 10.1016/j.ijbiomac.2019.03.042. Epub 2019 Mar 7.
Polysaccharide from Grifola frondosa is one of the best metal-ion chelating agents because of its structural characteristics and excellent functional activities. In this study, we synthesized and characterized a novel Grifola frondosa polysaccharide-chromium (III) [GFP-Cr(III)] complex. Response surface methodology (RSM) was used to optimize the reaction conditions for the maximum chelation rate of GFP-Cr(III) complex. The optimal reaction conditions obtained from RSM were as follows: concentration of CrCl 6.97 mg/mL, pH 7.75 and temperature 71.73 °C, respectively. The pH was the most significant factor, followed by reaction temperature and concentration of CrCl. Under the deduced optimal conditions (CrCl 7.0 mg/mL, pH 7.7 and temperature 70.0 °C), the experimental chelation rate was 28.01% ± 0.18% for GFP-Cr(III) complex, which agreed closely with the predicted value (27.61%). Fourier transform infrared (FTIR) spectroscopy revealed that the primary sites of chromium (III)-binding in polysaccharides were OH and CN groups, leading to the structure of GFP-Cr(III) complex was loose than the original polysaccharide. Nevertheless, Cr(III) did not make a fundamental change in the structure of GFP when comparing the FTIR spectra of GFP and GFP-Cr(III) complex. Additionally, the effects of GFP-Cr(III) complex on hyperglycemia and hyperlipidemia in high-fat diet (HFD) and streptozotocin (STZ)-induced diabetic mice were also investigated. Results showed that the serum total cholesterol (TC), total triglyceride (TG), low density lipoprotein cholesterol (LDL-C), fasting blood glucose levels and glucose tolerance in diabetic mice fed a high-fat diet (HFD) supplemented with GFP-Cr(III) complex (900 mg/kg day) were significantly lower than the diabetic group (P < 0.01). These results suggest that GFP-Cr(III) complex could be used as potential functional food ingredients for the prevention or treatment of hyperglycemia and hyperlipidemia.
灰树花多糖是一种最好的金属离子螯合剂，因为它具有结构特点和优异的功能活性。在本研究中，我们合成并表征了一种新型灰树花多糖-铬（III）[GFP-Cr（III）]配合物。响应面法（RSM）用于优化 GFP-Cr（III）配合物的最大螯合率的反应条件。从 RSM 获得的最佳反应条件如下：CrCl 浓度 6.97mg/mL，pH 7.75，温度 71.73°C。pH 是最显著的因素，其次是反应温度和 CrCl 浓度。在推断的最佳条件下（CrCl 7.0mg/mL，pH 7.7 和温度 70.0°C），GFP-Cr（III）配合物的实验螯合率为 28.01%±0.18%，与预测值（27.61%）非常接近。傅里叶变换红外（FTIR）光谱表明，多糖中铬（III）结合的主要部位是 OH 和 CN 基团，导致 GFP-Cr（III）配合物的结构比原始多糖疏松。然而，与 GFP-Cr（III）配合物的 FTIR 光谱相比，Cr（III）并没有使 GFP 的结构发生根本变化。此外，还研究了 GFP-Cr（III）配合物对高脂肪饮食（HFD）和链脲佐菌素（STZ）诱导的糖尿病小鼠高血糖和高血脂的影响。结果表明，高脂饮食（HFD）补充 GFP-Cr（III）配合物（900mg/kg/d）的糖尿病小鼠血清总胆固醇（TC）、总甘油三酯（TG）、低密度脂蛋白胆固醇（LDL-C）、空腹血糖水平和葡萄糖耐量明显低于糖尿病组（P<0.01）。这些结果表明，GFP-Cr（III）配合物可用作预防或治疗高血糖和高血脂的潜在功能性食品成分。
