Extraction, separation and identification of bioactive compounds in barley using LC-MS/MS

Abstract

An extraction procedure, based on alkaline and acidic hydrolysis, was developed, using the Box-Behnken design of experiment, with the aim to achieve an exhaustive recovery of free and also linked polyphenols, i.e. bonded to cell structures, in barley (Hordeum Vulgare L.) samples. An LC-MS/MS (MRM transition mode) method was developed for analysis of the samples extracted through the optimized procedure, and to achieve a correct quali-quantitative characterization of a specific group of polyphenols. The optimized procedure was also employed for the extraction and the identification of bioactive molecules in a dietary supplement composed of dried leaves of barley, commonly known as “young barley”. A selectivity study was carried out employing some of the compounds identified in young barley, and by using six different columns (C18, silica, ES-CN and OH5 types). The results showed that different mechanisms are involved in the retention of the standards, especially in case of HILIC mode.