Phytochemical study on Stachys kurdica BOISS & HOHEN
Abstract
Introduction: Stachys kurdica (Lamiaceae) is annual and perennial plant with rectangular stems, simple leaves, pistil inflorescences, radial calix, bilabial corolla and nutlet fruits in the form of ovules or spindles or linear . This plant is found in various natural habitats of Iran and especially in Golestan province from mountainous areas such as Chahar Bagh, Shahkoh, Ziarat and Golestan National Park .This plant used in the treatment of cardiovascular diseases, dermatological, gastrointestinal and used as anti-inflammatory, anti-convulsant, analgesic, etc.
Goals: The aim of this study was to identify the chemical compounds in the extracts and evaluate their antioxidant activity.
Methods: At first, the plant was collected from the lands overlooking the village of Sarai in the Islamic Island and after identification, the herbarium specimen was kept in the herbarium of the Faculty of Pharmacy. After drying the plant in shade and at laboratory temperature, it was extracted by n-hexane, chloroform and methanol solvents respectively in soxhlet apparatus.
The dried n-hexane extract (3.65 g) was separated by decantation funnel into two methanol and n-hexane phases. Methanol phase collected (2.95 g), was subjected to vacuum liquid chromatography (VLC) using a step gradient of acetone in n-hexane (0%, 2%, 4%, 6%, 8%, 10%, 20%, 40% , 60% , 80% , 100%). The dried fractions were stained by TLC in two solvent systems. After merging similar fractions and dry and crystallize them at room temperature, the NMR method was used for identification.
The MeOH extract (2g ˟3) was fractionated with SPE method by using Sep-Pack (ODS) and a step gradient methanol in water mixture (20%, 40%, 60%, 80% and 100%). These fractions were isolated by preparative HPLC and determination compounds by NMR method. Antioxidant activity of the plant was measured by DPPH on chloroform and MeOH extracts.
Conclusion: Using preparative HPLC , the 40% methanolic fractions were separated and the compounds were collected according to the chromatograph pattern and retention time .by this method 2 compounds were separated and their structure were determined by ¹H,¹³C-NMR .
The determined compounds were:
1) Scutellarein 7-O-β-[6”- (acetyl)] glucoside
2) Acacetin 7 –[6”( apiosyl)- 2”(acetyl)]-glucoside
The results of DPPH test showed that MeOH extract of S. kurdica has more antioxidant effect in comparison to the chloroform extract.