Biodegradability and toxicity of monorhamnolipid biosurfactant diastereomers

JOURNAL OF HAZARDOUS MATERIALS

卷:364

Article

Hogan, David E.¹  Tian, Fei¹  Malm, Scott W.²  Olivares, Christopher³  Pacheco, Ricardo Palos⁴  Simonich, Michael T.⁵  Hunjan, Anoop S.²  Tanguay, Robert L.⁵  Klimecki, Walter T.²  Polt, Robin⁴  Pemberton, Jeanne E.⁴  Curry, Joan E.¹  Maier, Raina M.¹ 

[1] Univ Arizona, Dept Soil Water & Environm Sci, Tucson, AZ 85721 USA

[2] Univ Arizona, Dept Pharmacol & Toxicol, Tucson, AZ 85721 USA

[3] Univ Arizona, Dept Chem & Environm Engn, Tucson, AZ 85721 USA

[4] Univ Arizona, Dept Chem & Biochem, Tucson, AZ 85721 USA

[5] Oregon State Univ, Dept Environm & Mol Toxicol, 1007 Agr & Life Sci Bldg, Corvallis, OR 97331 USA

关键词: Rhamnolipid;    Biodegradation;    Toxicity;    Stereochemistry;    Biosurfactant;   

DOI  :  10.1016/j.jhazmat.2018.10.050

来源: Elsevier

【 摘 要 】

Synthetic monorhamnolipids differ from biologically produced material because they are produced as single congeners, depending on the beta-hydroxyalkanoic acid used during synthesis. Each congener is produced as one of four possible diastereomers resulting from two chiral centers at the carbinols of the lipid tails [(R,R), (R,S), (S,R) and (S,S)]. We compare the biodegradability (CO, respirometry), acute toxicity (Microtox assay), embryo toxicity (Zebrafish assay), and cytotoxicity (xCELLigence and MTS assays) of synthetic rhamnosyl-beta-hydroxydecanoyl-beta-hydroxydecanoate (Rha-C10-C10) monorhamnolipids against biosynthesized monorhamnolipid mixtures (bio-mRL). All Rha-C10-C10 diastereomers and bio-mRL were inherently biodegradable ranging from 34 to 92% mineralized. The Microtox assay showed all Rha-C10-C10 diastereomers and bio-mRL are slightly toxic according to the US EPA ecotoxicity categories with 5 min EC50 values ranging from 39.6 to 87.5 mu M. The zebrafish assay showed that of 22 developmental endpoints tested, only mortality was observed at 120 h post fertilization; all Rha-C10-C10 diastereomers and bio-mRL caused significant mortality at 640 NI, except the Rha-C10-C10 (R,R) which showed no developmental effects. xCELLigence and MTS showed IC50 values ranging from 103.4 to 191.1 mu M for human lung cell line H1299 after 72 h exposure. These data provide key information regarding Rha-C10-C10 diastereomers that is pertinent when considering potential applications.

【 授权许可】

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