Distillable ionic liquid extraction of tannins from plant materials

Abstract

A distillable ionic liquid, N,N-dimethylammonium N′N′-dimethylcarbamate (DIMCARB), has been employed at room temperature to extract hydrolysable tannin materials from plant sources such as catechu (Acacia Catechu) and myrobolan (Terminalia Chebula). The extraction efficiencies (85%) were found be significantly higher compared to traditional extraction methods which utilise large quantities of water. Moreover, in the ionic liquid extraction method selectively higher concentrations of ellagic acid have been extracted from these raw materials. The results of hyde powder tests have revealed that the extracted materials have higher content of tannins compared to traditional extraction methods and this will be useful for tanning leather. Microbiological tests have shown that the ionic liquid extracted materials possess good shelf life and resist fungal growth.