Screening of phytoconstituents,investigation of antioxidant and antibacterial activity of methanolic and aqueous extracts of Cucumis sativus L.

The phytoconstituents,antioxidant potential and antibacterial activity of cucumis sativus (c. sativus) cultivated in pakistan were studied. in addition,the effect of extraction techniques (mercerization and refluxing) on the total phenolics,antioxidant activity and antibacterial potential of c. sativus fruit pulp were also studied. methanol extract was screened for its phytoconstituents. the antioxidant activity was assessed by determination of total phenolic contents (tpc),total flavonoid contents (tfc) and performing different in vitro antioxidant models such as 2,2-diphenyl- 1-picryl hydrazyl (dpph) free radical scavenging,reducing power,percent inhibition of peroxidation in linoleic acid and nitric oxide free radical scavenging assays. phytochemicals screening results revealed the presence of flavonoids,glycosides,tannic acid and saponins while absence of alkaloids,steroids and anthraquinones. the tpc was found in appreciable concentration (41.03 mg gallic acid equivalent (gae)/g) in extract obtained by 4h methanolic mercerization. long refluxing technique (4h refluxing) was found unfavorable to some extent as it resulted only 33.69 mg gae/g tpc in methanolic extract. anyhow the extraction with water using mercerization and refluxing techniques found least effective e.g. 4h mercerization and refluxing showed 14.14 and 18.16 mg gae/g respectively. antibacterial assay showed extract obtained by 4h and 2h methanolic mercerization have good potential to inhibit the growth (09.6±0.7 to 18.5±0.8 mm) of infection causing bacteria. the results of antioxidants and antibacterial in vitro assays advocated that 4h methanolic mercerization is an effective extraction technique. therefore,it could be concluded that methanolic mercerization is a technique of maximum extraction of phenolics and bioactive constituents.