Abstract:

In order to study effective extracting conditions, pigment constituents extracted from naturally brown cotton via ethanol/water solution system were investigated. The ratio of ethanol to water solution had significant influence on the pigment constituents extracted from naturally brown cotton. It is showed that the components with a retention time between 0-5min could be easily separated, while in the retention time from 7-17min a class of pigments could not be separated with satisfaction. The pigments in naturally brow cotton are strongly hydrophilic substances and extracting efficiency of the pigments was very low if using more than 90% ethanol to water solution, revealing not suitable for pigment extraction. While 0% ethanol solution was suitable for extraction of component in retention time of 1.4min, 30% ethanol solution was suitable for extraction of components in retention times of 1.7min, 2.2min and 9.6min, and 50% ethanol solution was suitable for extraction of component in retention time of 14.6min.