Biodegradability and toxicity of monorhamnolipid biosurfactant diastereomers.
J Hazard Mater
; 364: 600-607, 2019 02 15.
Article
em En
| MEDLINE
| ID: mdl-30390580
ABSTRACT
Synthetic monorhamnolipids differ from biologically produced material because they are produced as single congeners, depending on the ß-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-ß-hydroxydecanoyl-ß-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 5â¯min EC50 values ranging from 39.6 to 87.5⯵M. The zebrafish assay showed that of 22 developmental endpoints tested, only mortality was observed at 120â¯h post fertilization; all Rha-C10-C10 diastereomers and bio-mRL caused significant mortality at 640⯵M, 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⯵M for human lung cell line H1299 after 72â¯h exposure. These data provide key information regarding Rha-C10-C10 diastereomers that is pertinent when considering potential applications.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Tensoativos
/
Glicolipídeos
Limite:
Animals
/
Humans
Idioma:
En
Revista:
J Hazard Mater
Assunto da revista:
SAUDE AMBIENTAL
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Estados Unidos