title: Optimization of lycopene extraction from tomato cell suspension culture by response surface methodology.
abstract: Radioisotope-labeled lycopene is an important tool for biomedical research but currently is not commercially available. A tomato cell suspension culture system for the production of radioisotope-labeled lycopene was previously developed in our laboratory. In the current study, the goal was to optimize the lycopene extraction efficiency from tomato cell cultures for preparatory high-performance liquid chromatography (HPLC) separation. We employed response surface methodology (RSM), which combines fractional factorial design and a second-degree polynomial model. Tomato cells were homogenized with ethanol, saponified by KOH, and extracted with hexane, and the lycopene content was analyzed by HPLC-PDA. We varied five factors at five levels: ethanol volume (1.33-4 mL/g); homogenization period (0-40 s/g); saturated KOH solution volume (0-0.67 mL/g); hexane volume (1.67-3 mL/g); and vortex period (5-25 s/g). Ridge analysis by SAS suggested that the optimal extraction procedure to extract 1 g of tomato cells was at 1.56 mL of ethanol, 28 s homogenization, 0.29 mL of KOH, 2.49 mL of hexane, and 17.5 s vortex. These optimal conditions predicted by RSM were confirmed to enhance lycopene yield from standardized tomato cell cultures by more than 3-fold.
authors.affiliation: Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: Chi-Hua
authors.initials: CH
authors.lastname: Lu
authors.forename: Nancy J
authors.initials: NJ
authors.lastname: Engelmann
authors.forename: Mary Ann
authors.initials: MA
authors.lastname: Lila
authors.forename: John W
authors.initials: JW
authors.lastname: Erdman
mesh_terms: D002338:Carotenoids / Q000032:analysis / Q000302:isolation & purification*; D018929:Cell Culture Techniques; D002851:Chromatography, High Pressure Liquid; D000431:Ethanol; D005638:Fruit / Q000737:chemistry* / Q000166:cytology; D006878:Hydroxides; D000077276:Lycopene; D018551:Solanum lycopersicum / Q000737:chemistry*; D010755:Organophosphates; D010936:Plant Extracts / Q000737:chemistry; D017680:Potassium Compounds; D013223:Statistics as Topic
chemical_list: D006878:Hydroxides; D010755:Organophosphates; D010936:Plant Extracts; D017680:Potassium Compounds; C044268:hexylphosphonic acid diethyl ester; D002338:Carotenoids; D000431:Ethanol; D000077276:Lycopene; C029943:potassium hydroxide