Separation of chemical constituents in <i>Bidens pilosa</i> Linn. var. <i>radiata</i> Sch. Bip. by elution‐extrusion counter‐current chromatography using two new three‐phase solvent systems

Countercurrent chromatography (CCC) is a potent separation approach known for its remarkable efficiency and capacity in preparation. It's applied as a substitute or combined with different chromatographic techniques, resulting in its rebranding as multidimensional CCC (MDCCC). Numerous essential mixtures from natural products contain hundreds or thousands of distinct components of importance. These mix types are too complicated to separate in any reasonable time using a single CCC dimension. However, if a multidimensional technique is utilized, where a complex mixture is separated by an initial dimension, smaller fractions of that separation are gathered. Each fraction is studied individually; complex mixes can be resolved relatively quickly. Thus, several MDCCC separation features have been studied to demonstrate their advantages, limitations, and prospective capacity to separate exceedingly complex mixtures. In this review, MDCCC aspects, including principles, multiple columns system, multilayer coil J‐type, on‐line monitoring system, and applications, have been thoroughly_explored.

Section: Flavonoid and Phenolic Compoundsmentioning

confidence: 99%

Recent trends in multidimensional countercurrent chromatography

Muhire,

Sun,

Zhang

et al. 2024

“…The combination of elution and extrusion significantly increased the polarity span of CCC [15,16]. As a novel and efficient separation technology, EECCC has achieved some successful applications [17][18][19][20].…”

Section: Introductionmentioning

confidence: 99%

Elution–extrusion counter‐current chromatographic separation and theoretical mechanism of antioxidant from Robinia pseudoacacia flower

Liu

Zhang

Tang

et al. 2023

Robinia pseudoacacia flowers have attracted much attention because of numerous bioactivities. In this study, its extract showed the potential scavenging ability for 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulphonate) and 1,1-diphenyl-2-picrylhydrazyl free radicals. Under the guidance of antioxidant activity, the antioxidant extract was enriched by liquid-liquid extraction. The partition coefficients of the two main components in antioxidant extracts differed greatly, so in this study, elution-extrusion counter-current chromatography with the solvent system of n-hexane-ethyl acetate-methanol-water (2.5:5:2.5:5, v/v) was used to enhance the separation efficiency, and the two main components were successfully obtained. Among them, kaempferol showed strong antioxidant activity, which can be responsible for the activity of the extract. In order to deeply understand the antioxidant mechanism of kaempferol, the thermodynamics, frontier molecular orbital, and kinetics of scavenging free radicals were investigated by density functional theory. The results showed that 4′-OH in kaempferol was the most active group, which can scavenge free radicals by hydrogen atom transfer in non-polar solvents and activate 3-OH to generate double hydrogen atom transfer in the gas phase. But in polar solvents, it was more inclined to clear radicals through single electron transfer and proton transfer. The kinetic result showed that kaempferol needed 9.17 kcal/mol of activation energy to scavenge free radicals.

“…Compared to the classical CCC method, it expands the polarity window of separation, making it applicable to the analysis of complex samples [13]. EECCC has many applications in separating complex mixtures [14][15][16]. In previous work, our research group used the elution-extrusion mode to achieve the continuous injection and separation of maslinic acid and oleanolic acid in olive pomace.…”

Section: Introductionmentioning

confidence: 99%

A model for continuous sample feed and separation with counter‐current chromatography based on elution‐extrusion mode and its application

Sun

Huang

Pei

et al. 2022

A novel and meaningful theoretical model was established with counter-current chromatography based on the elution-extrusion mode for efficient continuous separation. For the experimental verification of the theory, the separation of the binary mixture luteolin/baicalein was studied. The velocity model and volume model of the chromatographic separation behavior of the target compounds in the separation process were given by theoretical analysis. The results showed that this method had obvious advantages in the separation of binary mixtures. In addition, the established model was used to predict and isolate oleuropein from olive leaves. A two-phase solvent system of n-butanol/ethyl acetate/methanol/water (1:19:1:19, v/v/v/v) was chosen for the continuous separation of oleuropein. After optimizing the conditions in this way, a large amount of sample loading was achieved; the volume of injections can reach 48 ml, approximately 35.29% of the volume of the counter-current chromatography column, and oleuropein with a purity of 86.42% was obtained within 80 min. The model provided technical support for the prediction of chromatographic behavior and operating parameters during continuous separation and preparation of counter-current chromatography. It has great application prospects and significance in separation preparation, especially in large-scale industrial preparation.