title: Emulsan quantitation by Nile red quenching fluorescence assay.
abstract: A Nile red fluorescent technique to quantify 20-200 microg ml(-1) of emulsan was developed. Nile red dissolved in DMSO showed an adsorption peak at 552 nm, and emission peak at 636 nm, with molar extinction coefficient of 19,600 cm(-1) M(-1). Nile red fluorescence in DMSO was proportionally quenched by emulsan and the quenching was time-dependent. The assay was used to follow the production of emulsan by cultures of Acinetobacter venetianus RAG-1.
authors.affiliation: Department of Biomedical Engineering, School of Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA.
authors.forename: Guillermo R
authors.initials: GR
authors.lastname: Castro
authors.forename: Bridget K
authors.initials: BK
authors.lastname: Larson
authors.forename: Bruce
authors.initials: B
authors.lastname: Panilaitis
authors.forename: David L
authors.initials: DL
authors.lastname: Kaplan
mesh_terms: D000150:Acinetobacter / Q000378:metabolism; D005069:Evaluation Studies as Topic; D005453:Fluorescence; D010078:Oxazines / Q000378:metabolism; D011135:Polysaccharides, Bacterial / Q000032:analysis* / Q000378:metabolism; D013050:Spectrometry, Fluorescence / Q000379:methods*
chemical_list: D010078:Oxazines; D011135:Polysaccharides, Bacterial; C036028:emulsan; C044808:nile red