title: Enzyme inhibitory and radical scavenging effects of some antidiabetic plants of Turkey.
abstract: OBJECTIVE
  Ethnopharmacological field surveys demonstrated that many plants, such as Gentiana olivieri, Helichrysum graveolens, Helichrysum plicatum ssp. plicatum, Juniperus oxycedrus ssp. oxycedrus, Juniperus communis var. saxatilis, Viscum album (ssp. album, ssp. austriacum), are used as traditional medicine for diabetes in different regions of Anatolia. The present study was designed to evaluate the in vitro antidiabetic effects of some selected plants, tested in animal models recently.
  
  
  METHODS
  α-glucosidase and α-amylase enzyme inhibitory effects of the plant extracts were investigated and Acarbose was used as a reference drug. Additionally, radical scavenging capacities were determined using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) ABTS radical cation scavenging assay and total phenolic content of the extracts were evaluated using Folin Ciocalteu method.
  
  
  RESULTS
  H. graveolens ethanol extract exhibited the highest inhibitory activity (55.7 % ± 2.2) on α-amylase enzyme. Additionally, J. oxycedrus hydro-alcoholic leaf extract had potent α-amylase inhibitory effect, while the hydro-alcoholic extract of J. communis fruit showed the highest α-glucosidase inhibitory activity (IC50: 4.4 μg/ml).
  
  
  CONCLUSIONS
  Results indicated that, antidiabetic effect of hydro-alcoholic extracts of H. graveolens capitulums, J. communis fruit and J. oxycedrus leaf might arise from inhibition of digestive enzymes.
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Gazi University, 06330 Hipodrom, Ankara, Turkey.
authors.forename: Nilüfer
authors.initials: N
authors.lastname: Orhan
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Gazi University, 06330 Hipodrom, Ankara, Turkey.
authors.forename: Sanem
authors.initials: S
authors.lastname: Hoçbaç
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Gazi University, 06330 Hipodrom, Ankara, Turkey.
authors.forename: Didem Deliorman
authors.initials: DD
authors.lastname: Orhan
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Gazi University, 06330 Hipodrom, Ankara, Turkey.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Asian
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Gazi University, 06330 Hipodrom, Ankara, Turkey.
authors.forename: Fatma
authors.initials: F
authors.lastname: Ergun
keywords: Gentiana olivier; Helichrysum; Juniperus; Viscum album; α-amylase; α-glucosidase