title: Antiviral activity of maca (Lepidium meyenii) against human influenza virus.
abstract: OBJECTIVE
  To investigate antiviral activity of maca to reduce viral load in Madin-Darby canine kidney (MDCK) cells infected with influenza type A and B viruses (Flu-A and Flu-B, respectively).
  
  
  METHODS
  Maca were extracted with methanol (1:2, v/v). The cell viability and toxicity of the extracts were evaluated on MDCK cells using method MTT assay. Antiviral activity of compounds against Flu-A and Flu-B viruses was assayed using a test for determining the inhibition of the cytopathic effect on cell culture and multiplex RT-PCR.
  
  
  RESULTS
  The methanol extract of maca showed low cytotoxicity and inhibited influenza-induced cytopathic effect significantly, while viral load was reduced via inhibition of viral growth in MDCK infected cells. Maca contains potent inhibitors of Flu-A and Flu-B with a selectivity index [cytotoxic concentration 50%/IC50] of 157.4 and 110.5, respectively.
  
  
  CONCLUSIONS
  In vitro assays demonstrated that maca has antiviral activity not only against Flu-A (like most antiviral agents) but also Flu-B viruses, providing remarkable therapeutic benefits.
authors.affiliation: Centro de Investigación de la Facultad de Ciencias de la Salud, Escuela de Medicina, Universidad Peruana de Ciencias Aplicadas-UPC, Lima, Peru. Electronic address: jdelvall@upc.edu.pe.
authors.forename: Juana
authors.initials: J
authors.lastname: Del Valle Mendoza
authors.affiliation: Servei de Microbiologia, Hospital Vall d'Hebron, Pg. Vall d'Hebron, 119-129, Barcelona 08035, Spain.
authors.forename: Tomàs
authors.initials: T
authors.lastname: Pumarola
authors.affiliation: Departamento Acadómico de Microbiologóa y Parasitologóa, Facultad de Ciencias Biológicas, Universidad Nacional Mayor de San Marcos (UNMSM), Avda, Venezuela s/n, Lima-1, Peru.
authors.forename: Libertad Alzamora
authors.initials: LA
authors.lastname: Gonzales
authors.affiliation: Centro de Investigación de la Facultad de Ciencias de la Salud, Escuela de Medicina, Universidad Peruana de Ciencias Aplicadas-UPC, Lima, Peru; Centre de Biotecnologia Molecular (CEBIM), Departament d'Enginyeria Quómica, ETSEIB, Universitat Politècnica de Catalunya (UPC) Barcelona Tech, Avda, Diagonal 647, Barcelona E-08028, Spain.
authors.forename: Luis J
authors.initials: LJ
authors.lastname: Del Valle
keywords: Antiviral activity; Flu; Influenza virus; Lepidium meyenii; Maca