title: 15-Lipoxygenase inhibition of Commelina benghalensis, Tradescantia fluminensis, Tradescantia zebrina.
abstract: OBJECTIVE
  To evaluate the 15-lipoxygenase inhibitory activity of the methanol leaf extracts of Commelina benghalensis, Tradescantia fluminensis (T. fluminensis) and Tradescantia zebrina.
  
  
  METHODS
  The inhibitory activity was evaluated using a spectrophotometric assay by observing the increase in absorbance at 234 nm due to the formation of the product 13-hydroperoxyoctadecadienoic acid. The extracts were also tested for the presence of terpenoids, saponins, tannins, flavonoids, steroids, phenolic compounds, alkaloids and cardiac glycosides.
  
  
  RESULTS
  All the extracts inhibited the action of 15-lipoxygenase at a concentration of 0.2 µg/mL. T. fluminensis and Tradescantia zebrina exhibited higher than 50% inhibition with T. fluminensis at 87.2%. T. fluminensis was partitioned with ethyl acetate and hexane and their IC50 values were determined at 8.72 µg/mL and 98.04 µg/mL, respectively.
  
  
  CONCLUSIONS
  T. fluminensis is a potentially good source of 15-lipoxygenase inhibitors.
authors.affiliation: Institute of Chemistry, College of Science, University of the Philippines, Diliman Quezon City, Philippines 1101.
authors.forename: Cean Socorro M
authors.initials: CS
authors.lastname: Alaba
authors.affiliation: Institute of Chemistry, College of Science, University of the Philippines, Diliman Quezon City, Philippines 1101.
authors.forename: Christine L
authors.initials: CL
authors.lastname: Chichioco-Hernandez
keywords: 15-Lipoxygenase; Inflammation; Medicinal plants; Plant extracts