Virginiamycin is an antibiotic produced by Streptomyces virginiae. The recovery process involves a crystallization step (solvent evaporation and precipitation using an antisolvent). To systematically evaluate the industrial crystallization process, the finished product was characterized by granulometry, X-ray diffraction, optical microscopy, scanning electron microscopy, hot-stage microscopy, thermogravimetry, near-infrared spectroscopy, and microbiological activity. The industrial process was simulated on a laboratory scale, analyzing the particle chord length size distribution as a function of time and studying the crystal formation in real time using focused beam reflectance. Analysis of the industrial process through quality by design and design of experiments showed that the crystallization process also influenced the values of the microbiological activity, and the current operation did not result in optimal values. The industrial process was modified within the certified conditions, which resulted in eliminating unexpected stops due to crystallization fouling and yielded high microbiological activity values in the finished product.

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工业结晶工艺的改进：弗吉尼亚霉素的生产

弗吉尼亚霉素是弗吉尼亚州链霉菌产生的抗生素。回收过程涉及结晶步骤（使用抗溶剂进行溶剂蒸发和沉淀）。为了系统地评估工业结晶过程，通过粒度分析，X射线衍射，光学显微镜，扫描电子显微镜，热台显微镜，热重分析，近红外光谱和微生物活性对成品进行了表征。在实验室规模上模拟了工业过程，分析了随时间变化的粒子弦长尺寸分布，并使用聚焦光束反射率实时研究了晶体形成。通过设计和实验设计，通过质量对工业过程进行分析，结果表明，结晶过程也影响了微生物活性的值，并且当前操作未获得最佳值。在认证的条件下对工业流程进行了修改，从而消除了由于结晶结垢引起的意外停机，并在最终产品中产生了很高的微生物活性值。