State Key Laboratory of Microbial Technology, Shandong University, Jinan, China.
J Surg Res. 2012 Apr;173(2):286-91. doi: 10.1016/j.jss.2010.09.013. Epub 2010 Oct 8.
Sophorolipids (SLs) obtained from yeast broth are mixtures of many sophorolipid molecules with different structures, and have attracted more attention since they were found to have good antimicrobial, anticancer, anti-inflammatory, and anti-HIV activities. We investigated the effects of sophorolipid molecules with different structures on human esophageal cancer cells in the present work.
Ten sophorolipid (SL) molecules were separated and purified from the sophorolipids mixture using preparative HPLC, and their structures were identified by MS analyses. The effects of sophorolipid molecules with different structures on two human esophageal cancer cell lines, KYSE 109 and KYSE 450, were investigated by MTT assay.
The structures of the 10 sophorolipid molecules differ in acetylation degree of sophorose, unsaturation degree of hydroxyl fatty acid, and lactonization or ring opening. The results demonstrated that the inhibition of diacetylated lactonic sophorolipid on two esophageal cancer cells (total inhibition at 30 μg/mL concentration) was stronger than that of monoacetylated lactonic sophorolipid (totally inhibition at 60 μg/mL concentration). Difference of unsaturation degree of hydroxyl fatty acid in SL molecules also had obvious influence on their cytotoxicity to esophageal cancer cells. The sophorolipid with one double bond in fatty acid part had the strongest cytotoxic effect on two esophageal cancer cells (total inhibition at 30 μg/mL concentration). Acidic sophorolipid showed hardly any anticancer activity against esophageal cancer cells.
In this study, the relationship of anticancer activities of natural sophorolipid molecules and the differences in their structures was revealed, which probably further reveals the mechanism of SL bioactivities and will be helpful in the modification of SL structures to obtain more novel SLs with excellent bioactivities.
酵母发酵液中提取的槐糖脂（SL）是具有不同结构的许多槐糖脂分子的混合物，由于其具有良好的抗菌、抗癌、抗炎和抗 HIV 活性而受到越来越多的关注。本研究考察了不同结构的槐糖脂分子对人食管癌细胞的影响。
采用制备型 HPLC 从槐糖脂混合物中分离纯化了 10 种槐糖脂（SL）分子，并通过 MS 分析鉴定了它们的结构。通过 MTT 法检测了不同结构的槐糖脂分子对两种人食管癌细胞系 KYSE109 和 KYSE450 的影响。
10 种槐糖脂分子的结构在槐糖的乙酰化程度、羟基脂肪酸的不饱和度、内酯化或开环方面存在差异。结果表明，二乙酰化内酯槐糖脂对两种食管癌细胞的抑制作用（在 30μg/mL 浓度下完全抑制）强于单乙酰化内酯槐糖脂（在 60μg/mL 浓度下完全抑制）。槐糖脂分子中羟基脂肪酸不饱和度的差异对其对食管癌细胞的细胞毒性也有明显影响。脂肪酸部分有一个双键的槐糖脂对两种食管癌细胞的细胞毒性最强（在 30μg/mL 浓度下完全抑制）。酸性槐糖脂对食管癌细胞几乎没有抗癌活性。
本研究揭示了天然槐糖脂分子的抗癌活性与其结构差异之间的关系，这可能进一步揭示了 SL 生物活性的机制，并有助于对 SL 结构进行修饰，以获得具有优异生物活性的新型 SL。
