脂肪酸燕麦β-葡聚糖酯结构对其临界自聚集浓度和胶束粒径的影响

Effects of Structure Parameters of Fatty Acid Oat β-Glucan Ester on Its Critical Aggregation Concentration and Micelle Size

采用响应曲面法探讨了脂肪酸燕麦β-葡聚糖酯（fatty acid oatβ-glucan esters,FAOGE）的结构对其临界聚集浓度（critical aggregation concentration,CAC）值和胶束粒径的影响。考察的FAOGE结构参数包括：燕麦β-葡聚糖的分子质量（7.4×10~4~16.8×10~4 D）、取代度（0.010±0.002~0.030±0.002）和酰基链长（6、8、10）。结果表明：不同结构的FAOGE溶液的CAC值在质量浓度为0.050~0.165 mg/m L的范围内,其大小随着取代度、酰基链长的降低或β-葡聚糖分子质量的增加而增加。结构参数对CAC值的影响顺序为：酰基链长〉取代度〉燕麦β-葡聚糖分子质量。不同结构的FAOGE自聚集体的平均粒径在264.7~530.9 nm的范围内,且随着取代度、酰基链长的降低及β-葡聚糖分子质量的增加而逐渐增加,结构参数对自聚集体的平均粒径的影响顺序为：取代度〉酰基链长〉燕麦β-葡聚糖分子质量。

The structural dependence of the self-aggregation behavior and size of micelles of fatty acid oat β-glucan esters（FAOGEs） was investigated in this study. The structure parameters of FAOGEs tested included molecular weight（Mw） of β-glucan（7.4 × 10~4 –16.8 × 10~4 D）, degree of substitution（DS） of oat β-glucan fatty acid esters（0.010 ± 0.002–0.030 ± 0.002）, and acyl chain length（6, 8 and 10）. The results showed that the critical aggregation concentration（CAC） of FAOGEs with different structures was in the range of 0.050–0.165 mg/m L and increased significantly with decreasing DS and acyl chain length and with increasing Mw of oat β-glucan. The effect of structure parameters of FAOGE on CAC was in the decreasing order： acyl chain length 〉 DS 〉 Mw of oat β-glucan. The average micelle size of FAOGEs with different structures was in the range of 264.7–530.9 nm and increased significantly with decreasing DS and acyl chain length and with increasing Mwof oat β-glucan. The effect of structure parameters of FAOGE on micelle size was in the decreasing order： DS 〉 acyl chain length 〉 Mw of oat β-glucan.