Interfacial tension (IFT) plays an important role in the processes like extraction and emulsification, and that low level IFT is usually preferred for better hydrodynamic performance of unit operations. The present study explores the effect of a saponin-rich extract from Glycyrrhiza glabra plant on the IFT of conventional n-hexane/water system. FTIR, HPLC and LC/MS analysis indicates a 31.39% glycyrrhizic acid as the main saponin, as well as flavonoid and phenolic compounds. The system IFT was decreased to 79.5% under the apparent CMC of about 0.20 wt%. Comparison of the obtained results with the previously reported results with extract products from other plants and with respect to much lower used dosage (less than 1:50) indicates the high preference of the product. More IFT reduction could still be achieved with temperature (within 293.2–313.2 K) and pH (within 5.5–8.5). Further, NaCl and CaCl₂ salts caused more IFT reduction due to salting-out effect and in the order of Hofmeister series; however, by strengthening the salting-in effect, IFT raised in the presence of Na₂SO₄. The obtained data at different temperatures were nicely reproduced with a correlation based on Szyszkowski adsorption isotherm, and the corresponding parameters were obtained with reasonable variations. Consequently, the adsorption thermodynamic parameters were determined.

中文翻译：

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甘草植物中富含皂素的提取物，低界面张力油/水提取的安全物质

界面张力（IFT）在萃取和乳化等过程中起着重要作用，并且通常优选使用低水平的IFT，以提高单元操作的流体力学性能。本研究探索了甘草中富含皂苷的提取物对常规n IFT的影响。-己烷/水系统。FTIR，HPLC和LC / MS分析表明，主要皂苷为31.39％的甘草酸，以及类黄酮和酚类化合物。在约0.20重量％的表观CMC下，系统IFT降低至79.5％。将获得的结果与先前报道的结果与其他植物的提取物进行比较，并且所使用的剂量要低得多（小于1:50），表明该产品具有很高的偏爱性。随着温度（293.2–313.2 K之内）和pH（5.5–8.5之内），仍可以实现更多的IFT降低。此外，由于盐析作用，NaCl和CaCl ₂盐引起更多的IFT降低，且顺序与Hofmeister级数相同。然而，通过增强盐化作用，在Na ₂ SO ₄存在下IFT升高。基于Szyszkowski吸附等温线，可以很好地再现在不同温度下获得的数据，并具有相关性，并且可以合理地获得相应的参数。因此，确定了吸附热力学参数。