Abstract:

In order to compare the influence of different alkaline extractions on the yield of water-unextractable arabinoxylans from wheat bran (B-WUAX), and on the composition of alkaline extract, five different alkaline extractions were used to extract B-WUAX. Combining with the optimum extraction method for B-WUAX, the content of total sugar, protein, B-WUAX and ferulic acid in the alkaline extract were determined. The results showed that using saturated barium hydroxide as the extraction the highest yield and content of B-WUAX were obtained, and the values were 14.3%, 78.90% respectively. Saturated barium hydroxide had the highest selectivity of B-WUAX which was more suitable as the extraction to study B-WUAX in laboratory. There was no relationship between the yield of B-WUAX and the pH of the extraction but a high relationship between the ferulic acid content and alkalinity of extraction. Extracting B-WUAX with stronger alkaline extraction, lower ferulic acid content was obtained. Using alkaline electrolysis water and sodium hydroxide solution of hydrogen peroxide as extraction, the ferulic acid content were 1220 μg/g and 1064 μg/g respectively. Using saturated barium hydroxide as the extraction, the ferulic acid content was 53.3 μg/g. Due to more simple extraction process, lower cost, and proper yield, sodium hydroxide was more suitable as the extraction to produce B-WUAX at large scale.