title: Extraction of functional ingredients from spinach (Spinacia oleracea L.) using liquid solvent and supercritical CO₂ extraction.
abstract: BACKGROUND
  In this work three different techniques were applied to extract dry leaves of spinach (Spinacia oleracea): solid-liquid extraction (SLE), pressurised liquid extraction (PLE) and supercritical fluid extraction (SFE) to investigate the influence of extraction solvent and technique on extracts composition and antioxidant activity. Moreover, the influence of carotenoids and phenolic compounds on the antioxidant and anti-inflammatory activities of spinach extracts was also studied.
  
  
  RESULTS
  The higher concentrations of carotenoids and the lower content of phenolic compounds were observed in the supercritical CO₂ extracts; whereas water and/or ethanol PLE extracts presented low amounts of carotenoids and the higher concentrations of phenolic compounds. PLE extract with the highest content of phenolic compounds showed the highest antioxidant activity, although SFE carotenoid rich extract also showed a high antioxidant activity. Moreover, both extracts presented an important anti-inflammatory activity.
  
  
  CONCLUSIONS
  PLE seems to be a good technique for the extraction of antioxidant and anti-inflammatory compounds from spinach leaves. Moreover, spinach phenolic compounds and carotenoids present a high antioxidant activity, whereas spinach carotenoids seem to show a higher anti-inflammatory activity than phenolic compounds. It is worth noting that of our knowledge this is the first time the anti-inflammatory activity of lipophilic extracts from spinach leaves is reported.
authors.affiliation: Instituto de Investigación en Ciencias de la Alimentación CIAL (CSIC-UAM), CEI UAM + CSIC, C/Nicolás Cabrera 9, Universidad Autónoma de Madrid, 28049, Madrid, Spain.
authors.forename: Laura
authors.initials: L
authors.lastname: Jaime
authors.forename: Erika
authors.initials: E
authors.lastname: Vázquez
authors.forename: Tiziana
authors.initials: T
authors.lastname: Fornari
authors.forename: María del Carmen
authors.initials: Mdel C
authors.lastname: López-Hazas
authors.forename: Mónica R
authors.initials: MR
authors.lastname: García-Risco
authors.forename: Susana
authors.initials: S
authors.lastname: Santoyo
authors.forename: Guillermo
authors.initials: G
authors.lastname: Reglero
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D000975:Antioxidants / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D002338:Carotenoids / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D002461:Cell Line, Transformed; D025924:Chromatography, Supercritical Fluid; D016207:Cytokines / Q000378:metabolism; D005503:Food Additives / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D006801:Humans; D059625:Liquid-Liquid Extraction; D009000:Monocytes / Q000276:immunology / Q000378:metabolism; D010636:Phenols / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D064209:Phytochemicals / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D018515:Plant Leaves / Q000737:chemistry*; D052616:Solid Phase Extraction; D018724:Spinacia oleracea / Q000737:chemistry* / Q000191:economics
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D000975:Antioxidants; D016207:Cytokines; D005503:Food Additives; D010636:Phenols; D064209:Phytochemicals; D010936:Plant Extracts; D002338:Carotenoids
keywords: anti-inflammatory activity; antioxidant activity; carotenoids; extraction techniques; spinach leaves; total polyphenol content