Characterization, in vitro binding properties, and inhibitory activity on pancreatic lipase of β-glucans from different Qingke (Tibetan hulless barley) cultivars

In order to explore Qingke beta-glucans as functional food ingredients for prevention of obesity, the physicochemical structures, in vitro binding properties, and inhibitory activities on pancreatic lipase of beta-glucans from three different Qingke cultivars, including Ganyucang (black), Dingqing (blue), and Zangqing 320 (white), were investigated and compared. Results showed that molecular weights, particle sizes, and intrinsic viscosities beta-glucans from colored (black and blue) Qingke cultivars were much higher than those of white Qingke beta-glucans, respectively. In addition, the constituent monosaccharides of beta-glucans from colored Qingke cultivars were determined as arabinose, xylose, glucose, and galactose, and glucose was the dominant monosaccharide. Furthermore, colored Qingke beta-glucans exerted strong fat binding, cholesterol binding, and bile-acid binding capacities, as well as inhibitory activities on pancreatic lipase, which were much higher than those of white Qingke beta-glucans. Indeed, the fat binding, cholesterol binding, and bile-acid binding capacities, as well as the inhibitory activities on pancreatic lipase of Qingke beta-glucans were positively associated with their molecular weights and intrinsic viscosities. Results are beneficial for better understanding of the structure-function relationship of Qingke beta-glucans, and beta-glucans from colored Qjngke cultivars (Ganyucang and Dingqing) could be further explored as functional food ingredients for prevention of obesity. (C) 2018 Elsevier B.V. All rights reserved.