title: Anti-hyperglycaemic and antioxidant effects ofBidens tripartitaand quantitative analysis on its active principles.
abstract: OBJECTIVE
  Bidensspecies are used for their antidiabetic properties traditionally in many countries. Aim of this study is to evaluate hypoglycaemic and antidiabetic activity ofBidens tripartitaextract and to identify its active compounds through bioactivity guided isolation technique.
  
  
  METHODS
  Hypoglycaemic effects ofB. tripartitaextract and its sub-extracts were investigated in normal and glucose-hyperglycaemic rats. Streptozotocin induced diabetic rats were used to examine antidiabetic activity of the extract and its sub-extracts after acute and sub-acute administration. Additionally,in vitroenzyme inhibitory and antioxidant activities were evaluated. HPLC analyses were carried out to determine the active constituents of the extract and its sub-extracts.
  
  
  RESULTS
  Throughin vivobioactivity-guided fractionation process, ethyl acetate and n-buthanol sub-extracts were found to have potent antidiabetic activity.In vitroenzyme inhibitory activities of the same sub-extracts were found to be potent. The highest total phenol, flavonoid contents and radical scavenging activity was determined in ethyl acetate sub-extract. According to LC-MS analyses, chlorogenic acid, luteolin and 7-O-glucoside of luteolin (cynaroside) were determined as the main components of the active sub-extracts.
  
  
  CONCLUSIONS
  According to our results,B. tripartitahas potent antidiabetic activity and its active constituents might be beneficial for diabetes and its complications.
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Gazi University, 06330, Etiler, Ankara, Turkey.
authors.forename: Nilüfer
authors.initials: N
authors.lastname: Orhan
authors.affiliation: Republic of Turkey Social Security Institution, 06520, Balgat, Ankara, Turkey.
authors.forename: Ülkü Gökçen
authors.initials: ÜG
authors.lastname: İçöz
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Ankara University, 06500, Tandogan, Ankara, Turkey.
authors.forename: Levent
authors.initials: L
authors.lastname: Altun
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Gazi University, 06330, Etiler, Ankara, Turkey.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Aslan
keywords: Antidiabetic; Bidens tripartite; Chlorogenic acid; Cynaroside; Luteolin; Streptozotocin