Biological activities of crude leaf extract and fractions of Scutellaria sibthorpii (Benth.) Halácsy: An endemic plant of North-Cyprus.

Scutellaria sibthorpii is used in treatment of bacterial infections, pains and inflammations. The leaf was extracted by maceration and then partitioned with hexane, ethyl acetate and n-butanol. The extract was screened for phytochemicals. The antioxidant activity was assayed using DPPH, H₂O₂ and β-carotene. The total phenolic and flavonoid contents were estimated using Folin-Ciocalteu's and AlCl₃. The crude extract/fractions were tested on E. coli, S. typhi, B. subtilis and S. aureus using agar disk diffusion. Lorke's method was used to determine the LD₅₀. The analgesic activity was determined using ethanoic acid-induced writhing, hotplate and formalin-induced nociception. Anti-inflammatory activity was investigated by means of formalin-induced acute inflammation. The antipyretic activity was studied using Brewer's yeast. The ethyl acetate fraction (EtFSs) had IC₅₀ of 0.4352mg/mL in the H₂O₂ and IC₅₀ of 0.00014mg/mL. The MIC of EtFSs against S. aureus was 1.25mg/mL and 2.5mg/mL on S. typhi. LD₅₀ of the CrESs/fractions were greater than 5000mg/Kg. The analgesic and anti-inflammatory activities were higher in EtFSs when compared to piroxicam. The fractions decrease the rectal temperature of the rats in the same way as paracetamol at 200mg/Kg. This research has for the first time validated the used of Scutellaria sibthorpii traditionally as analgesic, anti-inflammatory and antipyretic.