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目的应用Box-Behnken设计响应面法优化黑果枸杞总黄酮纯化工艺条件及相关参数。方法考察6种大孔吸附树脂静态、动态吸附和解吸性能,用单因素试验分别对上样浓度、上样体积、上样pH、洗脱液浓度、洗脱液体积和洗脱流速进行考察,以黑果枸杞总黄酮纯化后含量为指标,再从6个单因素中选出对解吸附试验影响最显著的3个因素进行三因素三水平Box-Behnken设计响应面实验。结果 NKA-9型大孔树脂为纯化黑果枸杞总黄酮的最佳树脂,最佳纯化工艺条件为总黄酮提取液浓度为4mg/mL,pH为4.0,按5BV进行上样,再用3VB的80%乙醇在2mL/min流速下进行洗脱,黑果枸杞总黄酮含量可以从4.54%提高到43.19%。结论此工艺对黑果枸杞总黄酮的纯化效果较好,工艺简单且稳定性良好,适用于工业化生产。 相似文献
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Sabra Al‐Mughairi Poulose Yesudhason Moza Al‐Busaidi Aaliah Al‐Waili Waleed A. K. Al‐Rahbi Nashwa Al‐Mazrooei Saoud H. Al‐Habsi 《Journal of food science》2013,78(7):T1082-T1090
The results of this study present analytical data of the mercury levels in several fish and shellfish species to create awareness among individuals of the risks associated with consuming fish contaminated with mercury. Mercury concentrations varied from a mean of 0.02 mg/kg in Indian mackerel to 0.19 mg/kg in shark in both fresh and frozen fish, from 0.02 mg/kg in sardines to 0.18 mg/kg in skipjack tuna in canned fish, and from 0.02 mg/kg in Indian mackerel to 0.79 mg/kg in shark in dried fish. Shellfish contained a slightly higher amount of mercury than fresh or frozen fish with a mean of 0.09 mg/kg. Trophic position, followed by habitat, was the most important factors for variability in mercury concentrations in fish and shellfish. The maximum safe weekly intake (MSWI) values of mercury were significantly higher for herbivores than for carnivores. The MSWI value for total mercury in the case of consuming most (72%) fish species was more than 5 kg; however, the MSWI value was never more than 5 kg in most (66%) shellfish species. Risks were identified upon consumption of 120 g of dried shark when exceeding the provisional tolerable weekly intake threshold (1.6 μg/kg) for methylmercury. Therefore, fish‐eating populations should reduce the quantity of dried shark to efficiently diminish the exposure to mercury. 相似文献
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