Partition of Tea Saponin with a Novel Recyclable Thermo-pH Aqueous Two-Phase Systems

Abstract

Aqueous two-phase systems (ATPS) have the advantages of environmentally friendly, high mass transfer efficiency, mild extraction conditions. However, it is difficult to recycle these components, which limits the large-scale application of ATPS in industrial production. In this study, a novel recyclable ATPS of PN/PADB4.78 was constructed with a thermo-responsive polymer PN and a pH-responsive polymer PADB4.78 for the partition study of tea saponin. The recovery of PN reached 98.71% by adjusting the temperature to above its lower critical solution temperature (LCST, 33.0 °C ) and the recovery of PADB4.78 was 97.32% by regulating the pH to its isoelectric point (pI, 4.78). Meanwhile, the phase formation mechanism of ATPS was studied by surface tension and low-field nuclear magnetic resonance (LF-NMR). The effects of polymer concentration, pH, temperature, types and concentrations of salt were investigated on tea saponin partition.In the 1.5% PN/3.5% PADB4.78 ATPS, the optimal partition coefficient (K) and extraction recovery (ERb) of crude tea saponin were 0.15 and 92.13% in the presence of 1.5 mM KCl at pH=7.6 and 25℃, respectively. The K and ERb of tea saponin from tea seeds were 0.12 and 94.50% with 7.5 mM LiBr at pH=8.0 and 25℃, respectively.

Double-Stimuli-Responsive (Temperature and pH) Aqueous Biphasic Systems Comprising Ionic Liquids

“…Double-stimuli-responsive systems provide a higher degree of customization of the target application and thus can be more easily adapted to industrial applications. Combining a thermo-sensitive polymer and a pH-sensitive polymer as the phase-forming agents is the most pursued route to develop double-stimuli-responsive ABS. − To the best of our knowledge, the development of IL-based ABS with double responsiveness to temperature and pH was not previously reported.…”

Protective Effect of Tea Saponins on Alcohol-Induced Gastric Mucosal Injury in Mice

“…Tea seed meal is generally considered useless after oil extraction, although it contains abundant triterpenoid saponins composed of glycosides, aglycones, and organic acid . Tea saponins have been extensively studied as natural surfactants for their emulsifying, decentralization, and foaming properties. − In addition, their pharmacological functions, such as antibacterial, anti-oxidation, and antihypertension, have also been investigated. − …”

“… 1 Tea saponins have been extensively studied as natural surfactants for their emulsifying, decentralization, and foaming properties. 2 − 4 In addition, their pharmacological functions, such as antibacterial, anti-oxidation, and antihypertension, have also been investigated. 5 − 7 …”