title: Sacha Inchi Oil (Plukenetia volubilis L.), effect on adherence of Staphylococus aureus to human skin explant and keratinocytes in vitro.
abstract: BACKGROUND
  Plukenetia volubilis L. (Euphorbiaceae) is a domesticated vine distributed from the high-altitude Andean rain forest to the lowlands of the Peruvian Amazon. Oil from the cold-pressed seeds, sold under the commercial name of Sacha Inchi Oil (SIO) is actually much in favour because it contains a high percentage of omega 3 and omega 6, and is hence used as a dietary supplement. SIO is also used traditionally for skin care, in order to maintain skin softness, and for the treatment of wounds, insect bites and skin infections, in a tropical context where the skin is frequently damaged.
  
  
  OBJECTIVE
  This study was designed in order to verify whether the traditional use of SIO for skin care would have any impact on Staphylococcus aureus growth and skin adherence, as S. aureus is involved in many skin pathologies (impetigo, folliculitis, furuncles and subcutaneous abscesses) being one if the main pathogens that can be found on the skin. Therefore, our objective was to assess SIO bactericidal activity and interference with adherence to human skin explants and the keratinocyte cell line. Cytotoxicity on that cells was also determined. The activity of SIO was compared to coconut oil (CocO), which is widely used for skin care but has different unsaturated fatty acids contents.
  
  
  METHODS
  Laboratory testing with certified oil, determined antibacterial activity against radio labelled S. aureus. Cytotoxic effects were measured with XTT on keratinocyte cells and with neutral red on human skin explants; phenol was used as cytotoxic control. Adherence assays were carried out by mixing H3-labelled S. aureus bacteria with keratinocyte cells and human skin explants, incubated with oils 2h before (to determine the inhibition of adherence, assimilated to a preventive effect) or 2h after the contact of the biological material with S. aureus (to assess the detachment of the bacteria, assimilated to a curative effect). Residual radioactivity measured after washings made it possible to determine the adherence intensity. Bactericidal effect was determined by colony counting on trypticase soy agar.
  
  
  RESULTS
  Laboratory assays showed that SIO and CocO, tested undiluted, were not cytotoxic on keratinocytes nor human explants and were not bactericidal neither. SIO was more active as antiadherent (preventive) than CocO on keratinocytes. There was no significant difference between detachment effects (curative) of both oils on keratinocytes but SIO was almost 5 times more active on the detachment of S. aureus from human skin explants.
  
  
  CONCLUSIONS
  From that study it can be concluded that the use of SIO on dermal cells is safe and efficient in the inhibition of S. aureus adherence. Our results tend to support the traditional use of undiluted SIO in skin care.
authors.affiliation: Institut de Recherche pour le Développement (IRD), UMR 152 Pharma-DEV, F-31062 Toulouse cedex 09, France; Université de Toulouse 3, UMR 152 Pharma-DEV, Faculté des Sciences Pharmaceutiques, F-31062 Toulouse cedex 09, France.
authors.forename: German
authors.initials: G
authors.lastname: Gonzalez-Aspajo
authors.affiliation: Fonderephar, Université Toulouse 3, Faculté des Sciences Pharmaceutiques, F-31062 Toulouse cedex 09, France.
authors.forename: Haouaria
authors.initials: H
authors.lastname: Belkhelfa
authors.affiliation: Fonderephar, Université Toulouse 3, Faculté des Sciences Pharmaceutiques, F-31062 Toulouse cedex 09, France.
authors.forename: Laïla
authors.initials: L
authors.lastname: Haddioui-Hbabi
authors.affiliation: Institut de Recherche pour le Développement (IRD), UMR 152 Pharma-DEV, F-31062 Toulouse cedex 09, France; Université de Toulouse 3, UMR 152 Pharma-DEV, Faculté des Sciences Pharmaceutiques, F-31062 Toulouse cedex 09, France.
authors.forename: Geneviève
authors.initials: G
authors.lastname: Bourdy
authors.affiliation: Institut de Recherche pour le Développement (IRD), UMR 152 Pharma-DEV, F-31062 Toulouse cedex 09, France; Université de Toulouse 3, UMR 152 Pharma-DEV, Faculté des Sciences Pharmaceutiques, F-31062 Toulouse cedex 09, France. Electronic address: eric.deharo@ird.fr.
authors.forename: Eric
authors.initials: E
authors.lastname: Deharo
mesh_terms: D001422:Bacterial Adhesion / Q000187:drug effects*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D019587:Dietary Supplements; D019665:Euphorbiaceae; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects / Q000382:microbiology; D010938:Plant Oils / Q000494:pharmacology*; D012867:Skin / Q000187:drug effects / Q000382:microbiology; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000254:growth & development / Q000502:physiology
chemical_list: D010938:Plant Oils
keywords: Human skin explant; Keratinocytes cells; Plukenetia volubilis L.; Sacha Inchi Oil; Staphylococcus aureus