TY - JOUR
T1 - Acetoin modulates conformational change of surfactin
T2 - Interfacial assembly and crude oil-washing performance
AU - Hu, Fangxiang
AU - Liu, Yuyue
AU - Lin, Junzhang
AU - Wang, Weidong
AU - Yu, Dinghua
AU - Li, Shuang
N1 - Publisher Copyright:
© 2021 Elsevier B.V.
PY - 2021/4
Y1 - 2021/4
N2 - Due to its special structure, the cyclic lipopeptide surfactin showed remarkable responsiveness to stimuli such as pH, temperature and metal ions. However, few studies investigated the effect of fermented by-products on the conformational change and interfacial assembly of surfactin. Here, the effect of acetoin, a primary metabolite of Bacillus subtilis, on the conformational change and interfacial assembly of surfactin was studied in detail. Surface tension measurements showed that the critical micelle concentration (CMC) of surfactin increased from 1.14 × 10−5 to 4.32 × 10−5 M in the presence of acetoin. Moreover, acetoin has increased the interfacial tension of surfactin aqueous solution-crude oil from 1.08 mN/m to 3.01 mN/m. Circular dichroism (CD) spectra and dynamic light-scattering (DLS) further demonstrated that acetoin had induced the conformational transition of surfactin from β-sheet to β-turn structure, and caused surfactin forming some larger micelle aggregations. Afterwards, it was further found that acetoin decreased the oil sand cleaning efficiency of surfactin from 59.7% to 6.6%, and deteriorated the O/W emulsion stability and altered the silicate wettability toward less water wet state. Based on the experimental results, a possible mechanism of the interaction between surfactin and acetoin was proposed.
AB - Due to its special structure, the cyclic lipopeptide surfactin showed remarkable responsiveness to stimuli such as pH, temperature and metal ions. However, few studies investigated the effect of fermented by-products on the conformational change and interfacial assembly of surfactin. Here, the effect of acetoin, a primary metabolite of Bacillus subtilis, on the conformational change and interfacial assembly of surfactin was studied in detail. Surface tension measurements showed that the critical micelle concentration (CMC) of surfactin increased from 1.14 × 10−5 to 4.32 × 10−5 M in the presence of acetoin. Moreover, acetoin has increased the interfacial tension of surfactin aqueous solution-crude oil from 1.08 mN/m to 3.01 mN/m. Circular dichroism (CD) spectra and dynamic light-scattering (DLS) further demonstrated that acetoin had induced the conformational transition of surfactin from β-sheet to β-turn structure, and caused surfactin forming some larger micelle aggregations. Afterwards, it was further found that acetoin decreased the oil sand cleaning efficiency of surfactin from 59.7% to 6.6%, and deteriorated the O/W emulsion stability and altered the silicate wettability toward less water wet state. Based on the experimental results, a possible mechanism of the interaction between surfactin and acetoin was proposed.
KW - Acetoin
KW - Emulsification stability
KW - Interfacial assembly
KW - Oil washing
KW - Stimulus responsive
KW - Surfactin
KW - Wettability alteration
UR - http://www.scopus.com/inward/record.url?scp=85100656817&partnerID=8YFLogxK
U2 - 10.1016/j.colsurfb.2021.111602
DO - 10.1016/j.colsurfb.2021.111602
M3 - 文章
C2 - 33571865
AN - SCOPUS:85100656817
SN - 0927-7765
VL - 200
JO - Colloids and Surfaces B: Biointerfaces
JF - Colloids and Surfaces B: Biointerfaces
M1 - 111602
ER -