Toxicity Profiling of Biosurfactants Produced by Novel Marine Bacterial Strains

Abstract

Surface active agents (SAAs), currently used in modern industry, are synthetic chemicals produced from non-renewable sources, with potential toxic impacts on humans and the environment. Thus, there is an increased interest for the identification and utilization of natural derived SAAs. As such, the marine environment is considered a promising source of biosurfactants with low toxicity, environmental compatibility, and biodegradation compared to their synthetic counterparts. MARISURF is a Horizon 2020 EU-funded project aiming to identify and functionally characterize SAAs, derived from a unique marine bacterial collection, towards commercial exploitation. Specifically, rhamnolipids produced by Marinobacter MCTG107b and Pseudomonas MCTG214(3b1) strains were previously identified and characterized while currently their toxicity profile was assessed by utilizing well-established methodologies. Our results showed a lack of cytotoxicity in in vitro models of human skin and liver as indicated by alamar blue and propidium iodide assays. Additionally, the use of the single gel electrophoresis assay, under oxidative stress conditions, revealed absence of any significant mutagenic/anti-mutagenic potential. Finally, both 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulphonicacid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) cell-free assays, revealed no significant anti-oxidant capacity for neither of the tested compounds. Consequently, the absence of significant cytotoxicity and/or mutagenicity justifies their commercial exploitation and potential development into industrial end-user applications as natural and environmentally friendly biosurfactants.

Non-Ionic Surfactants for Stabilization of Polymeric Nanoparticles for Biomedical Uses

“…Polyhydroxy Surfactants: Involve ethylene oxide-free nonionic stabilizers known for their dermatological properties and favorable environmental profile [42]. Rhamnolipids: Biosurfactants produced by marine bacteria have shown a lack of cytotoxicity and mutagenicity, which justifies their commercial exploitation as natural and ecological biosurfactants [43,44]. Animal-derived surfactants: in the same context of using biocompatible surfactants, bioglycolipids such as cerebrosides (which represent a group of non-ionic surfactants) and gangliosides (these are good cationic surfactants) have been proposed [45].…”

Characterisation of cytotoxicity and immunomodulatory effects of glycolipid biosurfactants on human keratinocytes

“…The cytotoxicity effects of rhamnolipids and sophorolipids have been demonstrated in vitro against mouse skin fibroblasts (NCTC clone 929), spontaneously transformed human keratinocyte cell line (HaCaT cells), and normal human dermal fibroblastic cells (Lydon et al 2017;Maeng et al 2018;Haque et al 2020;Rodríguez-López et al 2020;Voulgaridou et al 2021). However, most of these studies utilised either impure preparations, poorly characterised or single class of glycolipids resulting in significant interstudy variations, which in effect render glycolipids less attractive for use in skincare applications.…”

Characterization and Cytotoxicity of Pseudomonas Mediated Rhamnolipids Against Breast Cancer MDA-MB-231 Cell Line

“…The IC 50 value was 101.8 μg/ml for DNM50RL and 2.064 μg/ml for ascorbic acid as determined from GraphPad Prism software. At 1 mg/ml, MCTG107b and MCTG214 (3b1) derived biosurfactant exhibited only 9.67 ± 3.27% and 15.46 ± 4.03% inhibition for DPPH assay ( Voulgaridou et al, 2021 ).…”