Maneerat Suppasil, Bamba Takeshi, Harada Kazuo, Kobayashi Akio, Yamada Hidenori, Kawai Fusako
Laboratory of Applied Microbiology, Research Institute for Bioresources, Okayama University, Japan.
Appl Microbiol Biotechnol. 2006 Mar;70(2):254-9. doi: 10.1007/s00253-005-0050-6. Epub 2005 Jul 30.
A marine bacterium, Myroides sp. SM1, can grow on weathered crude oil and show emulsification of it. The biosurfactant able to emulsify crude oil was excreted in culture supernatant of Myroides sp. SM1 grown on marine broth, which was extracted with chloroform/methanol (1:1) at pH 7 and purified by normal and reverse phase silica gel column chromatographies. The compound was ninhydrin-positive, and the chemical structure was elucidated by nuclear magnetic resonance (NMR), infrared spectroscopy (IR), fast atom bombardment mass spectrometry, and gas chromatography-mass spectrometry (GC-MS) to be a mixture of L: -ornithine lipids, which were composed of L: -ornithine and a different couple of iso-3-hydroxyfatty acid (C(15)-C(17)) and iso-fatty acid (C(15) or C(16)) in a ratio of 1:1:1. The critical micelle concentration for a mixture of ornithine lipids was measured to be approximately 40 mg/l. A mixture of ornithine lipids exhibited emulsifying activity for crude oil in a broad range of pH, temperature, and salinity and showed higher surface activity for oil displacement test than other several artificial surfactants and a biosurfactant, surfactin.
一种海洋细菌，即Myroides sp. SM1，能够在风化原油上生长并使其乳化。能够乳化原油的生物表面活性剂在Myroides sp. SM1在海洋肉汤中生长的培养上清液中分泌出来，该上清液在pH 7时用氯仿/甲醇（1:1）萃取，并通过正相和反相硅胶柱色谱法纯化。该化合物对茚三酮呈阳性反应，其化学结构通过核磁共振（NMR）、红外光谱（IR）、快原子轰击质谱和气相色谱-质谱（GC-MS）得以阐明，为L-鸟氨酸脂质的混合物，由L-鸟氨酸以及不同的一对异-3-羟基脂肪酸（C(15)-C(17)）和异脂肪酸（C(15)或C(16)）以1:1:1的比例组成。测得鸟氨酸脂质混合物的临界胶束浓度约为40 mg/l。鸟氨酸脂质混合物在广泛的pH、温度和盐度范围内对原油表现出乳化活性，并且在驱油试验中比其他几种人工表面活性剂和一种生物表面活性剂——表面活性素表现出更高的表面活性。
