title: In vitro antiplasmodial and antioxidant activities of bisbenzylisoquinoline alkaloids from Alseodaphne corneri Kosterm.
abstract: OBJECTIVE
  To study antiplasmodial and antioxidant activities of the isolation of alkaloids from the active dichloromethane extract of Alseodaphne corneri.
  
  
  METHODS
  Phytochemical studies of the crude extract led to the isolation of six alkaloids using recycle high performance liquid chromatography and preparative thin layer chromatography. The antiplasmodial activity of the isolated compounds was evaluated using the histidine-rich protein II assay. The isolated alkaloids were also tested for their antioxidant activity using three different assays; DPPH, ferric reducing ability of plasma and metal chelating assays.
  
  
  RESULTS
  Malaria infection caused the formation of free radicals which subsequently led to oxidative stress and apoptosis. The antioxidant properties of the alkaloids under investigation revealed that in addition to the antiplasmodial activity, the alkaloids could also prevent oxidative stress. (+)-laurotetanine and (+)-norstephasubine exhibited strong antiplasmodial activities with IC50 values of 0.189 and 0.116 μM, respectively.
  
  
  CONCLUSIONS
  Interestingly, the two most potent compounds that exhibit antiplasmodial activity also exhibit good antioxidant activities. The crude dichloromethane extract and the isolated compounds exert substantial antiplasmodial and antioxidative activities which in turn suppress oxidative stress and cause less damage to the host.
authors.affiliation: Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Azeana
authors.initials: A
authors.lastname: Zahari
authors.affiliation: Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Abdulwali
authors.initials: A
authors.lastname: Ablat
authors.affiliation: Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Yasodha
authors.initials: Y
authors.lastname: Sivasothy
authors.affiliation: Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Jamaludin
authors.initials: J
authors.lastname: Mohamad
authors.affiliation: H.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan.
authors.forename: Muhammad I
authors.initials: MI
authors.lastname: Choudhary
authors.affiliation: Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia. Electronic address: khalijah@um.edu.my.
authors.forename: Khalijah
authors.initials: K
authors.lastname: Awang
keywords: Antioxidant; Antiplasmodial; Bisbenzylisoquinoline; Laurotetanine; Norstephasubine; Oxidative stress