Isolation, characterization and prediction of biologically active glycoside compounds quercetin-3-rutinoside from the fruits of Ficus sycomorus

Ficus sycomorus (F. sycomorus) is a medicinal plant which has been used traditionally for its medicinal benefits as metabolic, cardiovascular, respiratory, antispasmodic and anti-inflammatory remedy. Therefore the present work was designed to isolate and characterize antibacterial compounds from the fruits of F. sycomorus and their antibacterial activity was assayed. The crude extract was prepared by using different polarity solvents. The pure bioactive compounds were isolated and characterized from the ethyl acetate extract by using different chromatographic techniques. The antibacterial activity of the isolated pure compounds and crude extracts was assessed by using disc diffusion method. The crude extract and flavonoids quercetin-3-rutinoside 1 showed significant antibacterial activities against two Gram positive bacteria: Staphylococcus aureus (S. aureus) and Streptococcus pneunoniae (S. pneunoniae) and two Gram negative bacteria: Escherichia coli (E. coli) and Haemophilus influenza (H. influenza) in the disc diffusion assay. Inhibition zones were in the range of 0-13 mm. The maximum inhibition was shown by compound 1 at concentration 200 μg/ml against S. aureus (IZ = 13 mm) in comparison with the standard levofloxacin. Phytochemical investigation on the ethyl acetate crude extract of fruits resulted in the isolation of one glycoside compound named quercetin-3-rutinoside 1 with several other minor compounds. The structure was deduced on the basis of ¹H NMR, ^13C-NMR, DEPT, COSY, HMBC, and MS. The results showed that the isolated pure compound 1 has significant antibacterial activity, which can be used as natural antibiotics for the treatment of different infection diseases.