文献类型：期刊文献

英文题名：Micellization Activity of the Natural Lipopeptide [Glu₁, ASP₅] Surfactin-C15 in Aqueous Solution

作者：Zou, Aihua[1,2,3];Liu, Jing[1,2];Garamus, Vasil M.[3];Yang, Ying[1,2];Willumeit, Regine[3];Mu, Bozhong[1,2]

机构：[1]E China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]E China Univ Sci & Technol, Inst Appl Chem, Shanghai 200237, Peoples R China;[3]GKSS Forschungszentrum Geesthacht GmbH, D-21502 Geesthacht, Germany

年份：2010

卷号：114

期号：8

起止页码：2712

外文期刊名：JOURNAL OF PHYSICAL CHEMISTRY B

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000274842600020)】；

基金：The support of this work by the Alexander von Humboldt Foundation, by Research Fund for the New Teacher of the Doctoral Program of Higher Education of China (2008025 11024), and by the grant from the Ministry of Science and Technology of China (2007CB707801) is gratefully acknowledged.

语种：英文

摘要：Surface tension, small angle neutron scattering (SANS), freeze-fracture transmission electron microscopy (IFF-TEM), and circular dichroism (CD) have been used to study the self-aggregation properties of the natural lipopeptide [Glu(1), ASP(5)] surfactin-C15 in 0.01 M phosphate buffer Solution (PBS) at pH 7.4. It has been found that the critical micelle concentration (cmc) of surfactin is 1.54 x 10(-5) M, the surface tension at the cmc (sigma(cmc)) is 27.7 mN/m, and the area per molecule at the air-water interface is 107.8 angstrom(2). Surfactin molecules adopt a beta-sheet conformation already at low concentrations. This feature probably makes it surface-active at Such low concentrations. From SANS and FF-TEM results, it is seen that surfactin exhibits a strong self-assembly ability to form sphere-like micelles and some larger aggregates even at the rare low concentration. The aggregation number of sphere-like micelles is much smaller than that for conventional surfactants of similar alkyl chain length.