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所有酵母生物表面活性剂是否真的能够降低表面张力到30mN/m以下?
Kamil Wojciechowski1, Karolina Borucka2, Jolanta Mierzejewska2
1Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland; Department of Chemistry, University of Warmia and Mazury in Olsztyn, Olsztyn, Poland.
Colloids and surfaces. B, Biointerfaces
|August 16, 2023
概括
确定酵母生物表面活性剂的表面张力是棘手的. 测量结果可能是油乳液的产物,而不是真正的表面活动,需要谨慎地解释低值.
科学领域:
- 微生物学 微生物学
- 生物化学 生物化学
- 表面化学 表面化学
背景情况:
- 生物表面活性剂是微生物产生的表面活性化合物.
- 像Rhodotorula graminis和Rhodotorula babjevae这样的酵母菌株产生生物表面活性剂.
- 精确测量生物表面活性剂的表面张力对于理解其特性至关重要.
研究的目的:
- 调查生产生物表面活性剂的酵母培养基表面张力测量的可靠性.
- 在确定表面张力值时识别潜在的陷.
- 为了解释不同测量技术之间观察到的差异.
主要方法:
- 轴对称滴形状分析 (ADSA) 张力计用于测量动态表面张力.
- 威廉米板法用于基于力的表面张力测量.
- 分析的重点是培养基和Rhodotorula graminis和Rhodotorula babjevae的提取物.
主要成果:
- 随着时间的推移,ADSA显示表面张力下降,这表明表面活动减少.
- 威廉米板法产生了稳定的,低的表面张力值 (~30 mN/m).
- 这些差异归因于石油脱硫和扩散引起的测量工件,而生物表面活性剂有助于此.
结论:
- 在酵母培养基中观察到的低表面张力值可能是人工物,而不是真正的热力学吸附.
- 乳化油的存在,由生物表面活性剂稳定,影响测量结果.
- 对于酵母生物表面活性剂,报告的低表面张力值 (~30 ± 5 mN/m) 应谨慎解释,特别是如果存在乳液.
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