title: Safety assessment of aqueous extract from leaf Smallanthus sonchifolius and its main active lactone, enhydrin.
abstract: BACKGROUND
  Leaves of Smallanthus sonchifolius (Poepp. & Endl.) H. Robinson (yacon) have been used since pre-Columbian times in the Andean region to prepare medicinal herbal tea with beneficial health properties. However, there are still disagreements about the safe use. This work was carried out to evaluate the toxicity profile of both, 10% decoction of yacon leaves and their major active lactone, enhydrin.
  
  
  METHODS
  In vitro cytotoxicity assays were performed with Hep-G2, COS1, CHO-K1 and Vero cell lines using a test of metabolic competence based upon assessment of mitochondrial performance. In vivo toxicity study was performed in adult Wistar rats. In the acute oral toxicity each group of rats was orally given a single dose of 10% decoction or enhydrin. General condition, behavior and mortality were recorded for up to 14 days post treatment. In subchronic toxicity studies, both products were given orally for 90 days to rats. Body weight and food intakes were observed weekly. Hematological, clinical chemistry parameters and organ weight were determined in all animals at the end of the experimental period.
  
  
  RESULTS
  Cell viability decreased in a concentration dependent fashion when cells were incubated with 2-200 μg of 10% decoction and 0.015-7.5 μg of enhydrin. In acute study in rats, there were no deaths or signs of toxicity observed after oral administration of single doses of 10% decoction or enhydrin at any dose level up to the highest dose tested (14.0 g/kg and 0.32 g/kg, respectively). In subchronic studies in rats, both products administered orally for 90 days at daily doses of 0.07, 0.14 and 0.28 g 10% decoction/kg and 0.4, 0.8 and 8.0 mg enhydrin/kg, did not caused haematological, biochemical and histological alterations.
  
  
  CONCLUSIONS
  The results presented in this paper lead us to the conclusion that the use of 10% decoction and enhydrin is safe in rat at doses in which it is demonstrated the hypoglycaemic effect.
authors.affiliation: Biological Research Institute, National Council of Scientific and Technical Research and National University of Tucumán, Chacabuco 461, San Miguel de Tucumán, Argentina.
authors.forename: Carolina Serra
authors.initials: CS
authors.lastname: Barcellona
authors.forename: Wilfredo Marcelino
authors.initials: WM
authors.lastname: Cabrera
authors.forename: Stella Maris
authors.initials: SM
authors.lastname: Honoré
authors.forename: María Inés
authors.initials: MI
authors.lastname: Mercado
authors.forename: Sara Serafina
authors.initials: SS
authors.lastname: Sánchez
authors.forename: Susana Beatriz
authors.initials: SB
authors.lastname: Genta
mesh_terms: D000818:Animals; D019659:Asteraceae; D016466:CHO Cells; D019556:COS Cells; D002470:Cell Survival / Q000187:drug effects; D002522:Chlorocebus aethiops; D006224:Cricetinae; D003412:Cricetulus; D005260:Female; D056945:Hep G2 Cells; D006801:Humans; D007004:Hypoglycemic Agents / Q000302:isolation & purification / Q000633:toxicity*; D007783:Lactones / Q000302:isolation & purification / Q000633:toxicity; D008297:Male; D010936:Plant Extracts / Q000633:toxicity*; D018515:Plant Leaves; D017208:Rats, Wistar; D012717:Sesquiterpenes / Q000302:isolation & purification / Q000633:toxicity*; D023382:Toxicity Tests, Acute; D059550:Toxicity Tests, Subchronic; D014709:Vero Cells
chemical_list: D007004:Hypoglycemic Agents; D007783:Lactones; D010936:Plant Extracts; D012717:Sesquiterpenes; C521984:enhydrin