College of Science, Northeast Agricultural University, Harbin 150030, People's Republic of China.
College of Science, Northeast Agricultural University, Harbin 150030, People's Republic of China.
Ultrason Sonochem. 2018 Dec;49:206-214. doi: 10.1016/j.ultsonch.2018.08.005. Epub 2018 Aug 10.
In this study, the influence of ultrasound irradiation on the characterization and bioactivities of the polysaccharide from blackcurrant fruits (BCP, molecular weight: M = 3.26 × 10 kDa) was investigated. Two degraded polysaccharides (U-400, M = 1.89 × 10 kDa, and U-600, M = 1.32 × 10 kDa) were obtained by different ultrasound powers of 400 W and 600 W, respectively. Compared with BCP, U-400 and U-600 showed 63.52% and 68.85% reductions in the particle size (Z), respectively; moreover, the dynamic viscosity of BCP was reduced by 27.88%, and 33.63%, separately. The reducing sugar content and thermal stability increased with the increase of ultrasound intensity. The degraded polysaccharides contained the same monosaccharide species as those of BCP but at different molar ratios. Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopic analysis confirmed that the degraded polysaccharides and BCP exhibited the similar structural features, which were mainly composed of six glycosidic bonds. A reduction in surface area of the flake-like structure was observed in the degraded polysaccharides compared to that of BCP, and they had no triple helix structure. Furthermore, the precise structural characteristics of U-600 were identified by 2D NMR analysis. The results of the bioactivity assays indicated that the ultrasound irradiation could evidently enhance the antioxidant (hydroxyl and superoxide radicals scavenging, lipid peroxidation inhibition, and DNA damage protection activities), α-amylase and α-glucosidase inhibition activities of BCP. These activities increased in the order of U-600 > U-400 > BCP. In particular, the DNA protection and α-amylase inhibition activities for U-600 were 52.19 ± 1.34% and 75.98 ± 0.77%, respectively, which were 2 times higher than those of BCP. U-600 prepared with the higher-intensity ultrasound exhibited the best physicochemical properties and bioactivities among the three polysaccharides. These results suggested that ultrasound irradiation was an efficient, green method to produce value-added polysaccharide for use in functional food or medicine.
本研究考察了超声辐照对黑加仑果实多糖（BCP，分子量：M=3.26×10 kDa）的特性和生物活性的影响。通过分别使用 400 W 和 600 W 的不同超声功率，得到了两种降解多糖（U-400，M=1.89×10 kDa，和 U-600，M=1.32×10 kDa）。与 BCP 相比，U-400 和 U-600 的粒径（Z）分别减小了 63.52%和 68.85%；此外，BCP 的动态粘度分别降低了 27.88%和 33.63%。还原糖含量和热稳定性随超声强度的增加而增加。降解多糖与 BCP 含有相同的单糖种类，但摩尔比不同。傅里叶变换红外（FT-IR）和核磁共振（NMR）光谱分析证实，降解多糖和 BCP 具有相似的结构特征，主要由六种糖苷键组成。与 BCP 相比，片状结构的比表面积减小，且无三螺旋结构。此外，通过二维 NMR 分析确定了 U-600 的精确结构特征。生物活性测定结果表明，超声辐照可显著增强 BCP 的抗氧化（羟基和超氧自由基清除、脂质过氧化抑制和 DNA 损伤保护）、α-淀粉酶和α-葡萄糖苷酶抑制活性。这些活性按 U-600＞U-400＞BCP 的顺序增加。特别是，U-600 的 DNA 保护和α-淀粉酶抑制活性分别为 52.19±1.34%和 75.98±0.77%，比 BCP 高 2 倍。用高强度超声制备的 U-600 表现出三种多糖中最佳的物理化学性质和生物活性。这些结果表明，超声辐照是一种生产具有附加值的多糖的有效、绿色方法，可用于功能性食品或药物。
