植物油脂生物合成表面活性剂及产物分析

Biosynthesis and Characterization of Novel Surfactants Prepared using Vegetable Oils

摘要:

为了利用废弃油脂制备生物表面活性剂，用嗜麦芽寡养单胞菌(Stenotrophomonas maltophilia)WO-S14对不同植物油脂进行发酵，并对产物进行系统分析。通过发酵试验与性能分析，发现芝麻油的发酵产物具有优良的表面性能，对煤油的乳化率E24为75.22%，使水的表面张力降低至27.90 mN/m，且在较广的环境条件范围内具有良好稳定性。采用柱层析方法获得分离纯化的表面活性剂产物，通过薄层层析（TLC）、红外光谱（IR）、气质联用(GC-MS)、电喷雾质谱(ESI-MS)和串联质谱(MS/MS)等手段分析了产物的化学组成和结构，结果表明以芝麻油生物合成的表面活性剂主要是一种具有环状结构的脂肽，分子量为814，由含有15个碳原子的β-羟基脂肪酸和含有6个氨基酸分子的短肽组成，肽链中氨基酸连接顺序为：-Met-Glu-Ala-Ser-Ala-Val-，是一种新型脂肽类生物表面活性剂。

Abstract:

Different vegetable oils were fermented using Stenotrophomonas maltophilia WO-S14, with the objective of preparing biosurfactants from waste oil. The properties of the fermentation products were analyzed thoroughly and systematically. The fermentation product of sesame oil showed good surface properties; its emulsification index (E24) against kerosene was 75.22%; it could reduce the surface tension of water to 27.90 mN/m; it was highly stable under a wide range of environmental conditions. The surfactant product was purified by column chromatography and the chemical composition and structure of the purified product were studied by thin layer chromatography (TLC), infrared spectroscopy (IR), gas chromatography-mass spectrometry (GC-MS), electrospray ionization mass spectrometry (ESI-MS) and tandem mass spectrometry (MS/MS). The results indicated that the surfactant biosynthesized from sesame oil was a novel cyclic lipopeptide, with a molecular weight of 814. It was composed of a 15-carbon β-hydroxy fatty acid and a short peptide of six amino acid residues. The amino acid sequence of the peptide chain was Met-Glu-Ala-Ser-Ala-Val.