The bacterial strain F4, isolated from olive oil-contaminated soil, has been found to produce biosurfactants as confirmed by oil displacement test and the emulsification index results. The identification of the strain F4, by 16S ribosomal RNA gene, showed a close similarity to Bacillus safensis, therefore the strain has been termed Bacillus safensis F4. The Thin Layer Chromatography (TLC) and the High Pressure Liquid Chromatography-Mass Spectrometry (HPLC–MS/MS) demonstrated that the biosurfactant had a lipopeptide structure and was classified as surfactin. The present study showed also that the produced biosurfactant has an important antibacterial activity against several pathogen strains as monitored with minimum inhibitory concentration (MIC) micro-assays. In particular, it presented an interesting anti-planktonic activity with a MIC of 6.25 mg mL⁻¹ and anti-adhesive activity which exceeded 80% against the biofilm-forming Staphylococcus epidermidis S61 strain. Moreover, the produced lipopeptide showed an antitumor activity against T47D breast cancer cells and B16F10 mouse melanoma cells with IC₅₀ of 0.66 mg mL⁻¹ and 1.17 mg mL⁻¹, respectively. Thus, our results demonstrated that Bacillus safensis F4 biosurfactant exhibited a polyvalent activity via a considerable antibiofilm and antitumoral potencies.

中文翻译：

---

脂解菌株Bacillus safensis F4的表面活性素的抗菌，抗粘附和细胞毒活性。

从排油试验和乳化指数结果证实，从橄榄油污染的土壤中分离出的细菌菌株F4可产生生物表面活性剂。通过16S核糖体RNA基因鉴定F4菌株与枯草芽孢杆菌相似，因此被称为枯草芽孢杆菌。F4。薄层色谱法（TLC）和高压液相色谱-质谱法（HPLC-MS / MS）表明，该生物表面活性剂具有脂肽结构，被归类为表面活性素。本研究还表明，所产生的生物表面活性剂对几种病原体菌株具有重要的抗菌活性，这是通过最小抑菌浓度（MIC）微量测定法进行监测的。尤其是，它呈现出有趣的抗浮游生物活性，MIC为6.25 mg mL ^-1，并且对形成生物膜的表皮葡萄球菌S61菌株的抗黏附活性超过80％。此外，产生的脂肽对T47D乳腺癌细胞和B16F10小鼠黑素瘤细胞具有IC ₅₀的抗肿瘤活性。分别为0.66 mg mL ^-1和1.17 mg mL ^-1。因此，我们的结果表明，安全芽孢杆菌F4生物表面活性剂通过相当大的抗生物膜和抗肿瘤效力表现出多价活性。