title: Application of response surface methodology to optimize pressurized liquid extraction of antioxidant compounds from sage (Salvia officinalis L.), basil (Ocimum basilicum L.) and thyme (Thymus vulgaris L.).
abstract: The present study optimized pressurized liquid extraction (PLE) conditions using Dionex ASE® 200, USA to maximize the antioxidant activity [Ferric ion Reducing Antioxidant Power (FRAP)] and total polyphenol content (TP) of the extracts from three spices of Lamiaceae family (sage, basil and thyme). Optimal conditions with regard to extraction temperature (66-129 °C) and solvent concentration (32-88% methanol) were identified using response surface methodology (RSM). For all three spices, results showed that 129 °C was the optimum temperature with regard to antioxidant activity. Optimal methanol concentrations with respect to the antioxidant activity of sage and basil extracts were 58% and 60% respectively. Thyme showed a different trend with regard to methanol concentration and was optimally extracted at 33%. Antioxidant activity yields of the optimal PLE were significantly (p < 0.05) higher than solid/liquid extracts. Predicted models were highly significant (p < 0.05) for both total phenol (TP) and FRAP values in all the spices with high regression coefficients (R(2)) ranging from 0.651 to 0.999.
authors.affiliation: School of Food Science and Environmental Health, Dublin Institute of Technology, Cathal Brugha Street, Dublin 1, Ireland. mohammad.hossain@teagasc.ie
authors.forename: M B
authors.initials: MB
authors.lastname: Hossain
authors.forename: N P
authors.initials: NP
authors.lastname: Brunton
authors.forename: A B
authors.initials: AB
authors.lastname: Martin-Diana
authors.forename: C
authors.initials: C
authors.lastname: Barry-Ryan
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002934:Cinnamates / Q000032:analysis; D053630:Depsides / Q000032:analysis; D005290:Ferric Compounds / Q000737:chemistry; D008956:Models, Chemical; D018649:Ocimum basilicum / Q000737:chemistry*; D010636:Phenols / Q000032:analysis; D010936:Plant Extracts / Q000032:analysis; D011108:Polymers / Q000032:analysis; D011312:Pressure; D027543:Salvia officinalis / Q000737:chemistry*; D017365:Spices / Q000032:analysis; D013696:Temperature; D046930:Thymus Plant / Q000737:chemistry*; D000097123:Rosmarinic Acid
chemical_list: D000975:Antioxidants; D002934:Cinnamates; D053630:Depsides; D005290:Ferric Compounds; D010636:Phenols; D010936:Plant Extracts; D011108:Polymers; D000097123:Rosmarinic Acid; C011908:melanoidin polymers