title: Bioactive compounds from endemic plants of Southwest Portugal: inhibition of acetylcholinesterase and radical scavenging activities.
abstract: BACKGROUND
  Natural products are reported to have substantial neuroprotective activity due to their radical scavenging capacity, and also acetylcholinesterase (AChE) inhibitory capacity, both activities important in neurodegeneration.
  
  
  OBJECTIVE
  The undesirable side effects of compounds in pharmacological use make it important to identify natural neuroprotective molecules. This work assesses the potential of five endemic Portuguese plants as sources of neuroprotective compounds.
  
  
  METHODS
  Antioxidant capacity for peroxyl radical was determined by Oxygen Radical Absorbance Capacity method and for hydroxyl by Electron Paramagnetic Resonance, as well as AChE inhibitory capacity of the plant hydroethanolic extracts. The molecules responsible for these valuable properties were also tentatively identified by HPLC.
  
  
  CONCLUSIONS
  Armeria rouyana and Thymus capitellatus presented some of the highest phenolic contents (76.60 ± 7.19 and 12.82 ± 0.24 mg GAE g−1 dw, respectively) and antioxidant capacities (592 ± 116 and 449 ± 57 μmol TE g−1 dw, respectively). The flavonoids were identified as the phytomolecules related to the antioxidant capacity of these plant extracts; in the case of A. rouyana, l-ascorbic acid also made an important contribution (3.27 ± 0.26 mg g−1 dw). Plant extracts clearly demonstrated effective AChE inhibitory activity (480 ± 98 and 490 ± 46 μg mL−1, respectively), that could be associated to polyphenols.
  
  
  CONCLUSIONS
  The extracts of A. rouyana and T. capitellatus and their active components, especially polyphenols, demonstrate interesting neuroprotective potential. They, therefore, deserve further study as their phytomolecules are promising sources of either natural neuroprotective products and/or novel lead compounds.
authors.affiliation: Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, 2780-157 Oeiras, Portugal.
authors.forename: Lucélia
authors.initials: L
authors.lastname: Tavares
authors.forename: Sofia
authors.initials: S
authors.lastname: Fortalezas
authors.forename: Meenu
authors.initials: M
authors.lastname: Tyagi
authors.forename: David
authors.initials: D
authors.lastname: Barata
authors.forename: Ana Teresa
authors.initials: AT
authors.lastname: Serra
authors.forename: Catarina Maria Martins
authors.initials: CM
authors.lastname: Duarte
authors.forename: Rui Oliveira
authors.initials: RO
authors.lastname: Duarte
authors.forename: Rodrigo Pedro
authors.initials: RP
authors.lastname: Feliciano
authors.forename: Maria Rosário
authors.initials: MR
authors.lastname: Bronze
authors.forename: Maria Dalila
authors.initials: MD
authors.lastname: Espírito-Santo
authors.forename: Ricardo Boavida
authors.initials: RB
authors.lastname: Ferreira
authors.forename: Cláudia Nunes
authors.initials: CN
authors.lastname: Santos
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D002800:Cholinesterase Inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D002851:Chromatography, High Pressure Liquid; D016166:Free Radical Scavengers / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D018696:Neuroprotective Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D010946:Plants, Medicinal / Q000737:chemistry*; D059808:Polyphenols / Q000302:isolation & purification / Q000494:pharmacology; D011174:Portugal
chemical_list: D000975:Antioxidants; D002800:Cholinesterase Inhibitors; D016166:Free Radical Scavengers; D018696:Neuroprotective Agents; D010936:Plant Extracts; D059808:Polyphenols