Effects of acetylation on the emulsifying properties of Artemisia sphaerocephala Krasch polysaccharide
Effects of acetylation on the emulsifying properties of Artemisia sphaerocephala Krasch polysaccharide
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DOI：
10.1016/j.carbpol.2016.02.039
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发表时间：
2016-06-25
影响因子：
11.2
通讯作者：
Ma, Zhen
中科院分区：
文献类型：
--
作者：
Li, Junjun;Hu, Xinzhong;Ma, Zhen
在本研究中，从白蒿中提取的多糖。种子（ASKP）被乙酰化以改善大分子的乳化性能。乙酰化的方法有多种，其中以甲酰胺为溶剂的乙酸酐-吡啶法被发现是最有效的一种。本研究中使用 HPSEC-MALS、FTIR 和 H-1 NMR 技术成功生产了具有不同取代度 (DS) 的乙酰化 ASKP 并进行了结构表征。结果表明乙酰化处理会导致ASKP的降解。而且，随着DS的增加，分子量和回转半径均增加，且分子构象趋于更加紧凑。低 DS（DS：0.04 和 0.13）使乙酰化 ASKP 的粘度低于 ASKP。随着 DS 的增加，乙酰化 ASKP 的粘度增加并超过 ASKP。与 ASKP 相比，乙酰化 ASKP 可以更大程度地降低表面张力，并在油/水乳液体系中表现出更小的液滴尺寸 (ZD)。乙酰化ASKP能够在60℃下稳定油/水乳液3天，其性能与阿拉伯树胶一样好。总之，ASKP 的这种疏水改性赋予了其更好的乳化性能。 (C) 2016 Elsevier Ltd. 保留所有权利。
In the present study, polysaccharides extracted from Artemisia sphaerocephala Krasch. seeds (ASKP) were acetylated to improve the emulsifying properties of the macromolecules. Several methods were applied for the acetylation purpose, among which the acetic anhydride-pyridine method with formamide as solvent was found to be the most effective one. Acetylated ASKPs with various degree of substitution (DS) were successfully produced and structurally characterized using HPSEC-MALS, FTIR and H-1 NMR techniques in this study. Results showed that acetylation treatment could cause the degradation of ASKP. Moreover, with the increase of DS, both the molecular weight and radius of gyration increased, as well as the molecular conformation trended to be more compact. Low DS (DS: 0.04 and 0.13) conferred acetylated ASKP a lower viscosity than that of ASKP. With the increase of DS, the viscosity of acetylated ASKPs increased and exceeded that of ASKP. Compared with ASKP, acetylated ASKPs could reduce the surface tension to a greater extent and demonstrated a much smaller droplet size (ZD) in an oil/water emulsion system. Acetylated ASKPs were capable of stabilizing the oil/water emulsion for 3 days at 60 degrees C, whose performance was as good as that of gum acacia. In conclusion, such a hydrophobic modification on ASKP conferred it better emulsifying properties. (C) 2016 Elsevier Ltd. All rights reserved.