Department of Phytochemistry, Medicinal Plants and Drugs Research Institute, Shahid Beheshti University, G.C., Evin, Tehran, Iran.
Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, Via L. Borsari 46, 44121, Ferrara, Italy.
Anal Bioanal Chem. 2024 Apr;416(10):2553-2564. doi: 10.1007/s00216-024-05228-6. Epub 2024 Mar 9.
Crocin-I, a valuable natural compound found in saffron (Crocus sativus L.), is the most abundant among the various crocin structures. Developing a cost-effective and scalable purification process to produce high-purity crocin-I is of great interest for future investigations into its biological properties and its potential applications in the treatment of neurological disorders. However purifying crocin-I through single-column preparative chromatography (batch) poses a yield-purity trade-off due to structural similarities among crocins, meaning that the choice of the collection window sacrifices either yield in benefit of higher purity or vice versa. This study demonstrates how the continuous countercurrent operating mode resolves this dilemma. Herein, a twin-column MCSGP (multicolumn countercurrent solvent gradient purification) process was employed to purify crocin-I. This study involved an environmentally friendly ethanolic extraction of saffron stigma, followed by an investigation into the stability of the crocin-I within the feed under varying storage conditions to ensure a stable feed composition during the purification. Then, the batch purification process was initially designed, optimized, and subsequently followed by the scale-up to the MCSGP process. To ensure a fair comparison, both processes were evaluated under similar conditions (e.g., similar total column volume). The results showed that, at a purity grade of 99.7%, the MCSGP technique demonstrated significant results, namely + 334% increase in recovery + 307% increase in productivity, and - 92% reduction in solvent consumption. To make the purification process even greener, the only organic solvent employed was ethanol, without the addition of any additive. In conclusion, this study presents the MCSGP as a reliable, simple, and economical technique for purifying crocin-I from saffron extract, demonstrating for the first time that it can be effectively applied as a powerful approach for process intensification in the purification of natural products from complex matrices.
西红花中的主要类胡萝卜素藏红花素 I 是一种有价值的天然化合物，它在各种藏红花素结构中含量最丰富。开发一种经济高效且可扩展的纯化工艺来生产高纯度的藏红花素 I，对于研究其生物特性以及在治疗神经紊乱方面的潜在应用具有重要意义。然而，由于藏红花素结构相似，通过单柱制备型色谱（批处理）来纯化藏红花素 I 会导致产率和纯度之间的权衡取舍，这意味着收集窗口的选择要么牺牲产率以提高纯度，要么反之。本研究展示了连续逆流操作模式如何解决这一困境。本文采用双柱 MCSGP（多柱逆流溶剂梯度纯化）工艺来纯化藏红花素 I。该研究涉及从西红花柱头进行环保的乙醇提取，随后研究了在不同储存条件下进料中藏红花素 I 的稳定性，以确保在纯化过程中进料组成稳定。然后，最初设计、优化了批处理纯化工艺，随后进行了放大到 MCSGP 工艺的研究。为了进行公平比较，两种工艺均在相似的条件下进行评估（例如，总柱体积相似）。结果表明，在纯度等级为 99.7%时，MCSGP 技术具有显著的效果，即回收率提高了 334%，生产效率提高了 307%，溶剂消耗减少了 92%。为了使纯化过程更加环保，仅使用乙醇作为有机溶剂，无需添加任何添加剂。总之，本研究展示了 MCSGP 是一种从西红花提取物中纯化藏红花素 I 的可靠、简单且经济的技术，首次证明它可有效地应用于从复杂基质中纯化天然产物的强化过程。
