TY - JOUR
T1 - Biodegradability and toxicity of monorhamnolipid biosurfactant diastereomers
AU - Hogan, David E.
AU - Tian, Fei
AU - Malm, Scott W.
AU - Olivares, Christopher
AU - Palos Pacheco, Ricardo
AU - Simonich, Michael T.
AU - Hunjan, Anoop S.
AU - Tanguay, Robert L.
AU - Klimecki, Walter T.
AU - Polt, Robin
AU - Pemberton, Jeanne E.
AU - Curry, Joan E.
AU - Maier, Raina M.
N1 - Publisher Copyright:
© 2018 Elsevier B.V.
PY - 2019/2/15
Y1 - 2019/2/15
N2 - Synthetic monorhamnolipids differ from biologically produced material because they are produced as single congeners, depending on the β-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 (CO2 respirometry), acute toxicity (Microtox assay), embryo toxicity (Zebrafish assay), and cytotoxicity (xCELLigence and MTS assays) of synthetic rhamnosyl-β-hydroxydecanoyl-β-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 μM. 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 μM, 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 μM 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.
AB - Synthetic monorhamnolipids differ from biologically produced material because they are produced as single congeners, depending on the β-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 (CO2 respirometry), acute toxicity (Microtox assay), embryo toxicity (Zebrafish assay), and cytotoxicity (xCELLigence and MTS assays) of synthetic rhamnosyl-β-hydroxydecanoyl-β-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 μM. 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 μM, 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 μM 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.
KW - Biodegradation
KW - Biosurfactant
KW - Rhamnolipid
KW - Stereochemistry
KW - Toxicity
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UR - http://www.scopus.com/inward/citedby.url?scp=85055730562&partnerID=8YFLogxK
U2 - 10.1016/j.jhazmat.2018.10.050
DO - 10.1016/j.jhazmat.2018.10.050
M3 - Article
C2 - 30390580
AN - SCOPUS:85055730562
SN - 0304-3894
VL - 364
SP - 600
EP - 607
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
ER -