title: Optimization of ultrasound assisted extraction of bioactive components from brown seaweed Ascophyllum nodosum using response surface methodology.
abstract: The objective of this study was to investigate the effect of key extraction parameters of extraction time (5-25 min), acid concentration (0-0.06 M HCl) and ultrasound amplitude (22.8-114 μm) on yields of bioactive compounds (total phenolics, fucose and uronic acid) from Ascophyllumnodosum. Response surface methodology was employed to optimize the extraction variables for bioactive compounds' yield. A second order polynomial model was fitted well to the extraction experimental data with (R(2)>0.79). Extraction yields of 143.12 mgGAE/gdb, 87.06 mg/gdb and 128.54 mg/gdb were obtained for total phenolics, fucose and uronic acid respectively at optimized extraction conditions of extraction time (25 min), acid concentration (0.03 M HCl) and ultrasonic amplitude (114 μm). Mass spectroscopy analysis of extracts show that ultrasound enhances the extraction of high molecular weight phenolic compounds from A. nodosum. This study demonstrates that ultrasound assisted extraction (UAE) can be employed to enhance extraction of bioactive compounds from seaweed.
authors.affiliation: School of Biosystems Engineering, University College Dublin, Dublin 4, Ireland.
authors.forename: Shekhar U
authors.initials: SU
authors.lastname: Kadam
authors.affiliation: Teagasc Food Research Centre, Ashtown, Dublin 15, Ireland. Electronic address: brijesh.tiwari@teagasc.ie.
authors.forename: Brijesh K
authors.initials: BK
authors.lastname: Tiwari
authors.affiliation: Teagasc Food Research Centre, Ashtown, Dublin 15, Ireland; Department of Life Sciences, School of Science, Sligo Institute of Technology Sligo, Sligo, Ireland.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Smyth
authors.affiliation: School of Biosystems Engineering, University College Dublin, Dublin 4, Ireland.
authors.forename: Colm P
authors.initials: CP
authors.lastname: O'Donnell
mesh_terms: D044646:Ascophyllum / Q000737:chemistry*; D005591:Chemical Fractionation / Q000379:methods*; D005643:Fucose / Q000302:isolation & purification*; D006851:Hydrochloric Acid / Q000737:chemistry; D008962:Models, Theoretical; D010636:Phenols / Q000302:isolation & purification*; D012624:Seaweed / Q000737:chemistry*; D013223:Statistics as Topic; D013634:Tannins / Q000032:analysis / Q000302:isolation & purification; D013997:Time Factors; D014465:Ultrasonics / Q000379:methods*; D014574:Uronic Acids / Q000302:isolation & purification*
chemical_list: D010636:Phenols; D013634:Tannins; D014574:Uronic Acids; D005643:Fucose; D006851:Hydrochloric Acid
keywords: Extraction; Fucose; Phenolic compounds; Seaweed; Ultrasound; Uronic acids