Abstract:
The flavonoids of the leaves of PsidiumGuajavawas investigated .Extraction of the leaves with 95% ethanol gave a crude .Phytochemical screening revealed the presence of flavonoids , steroids and the absence of alkaloids . The crude was fractionated over silica gel with acetic acid 30% only a single flavonoid was detected on UV light .The structure of the flavonoid was elucidated on basis of its spectral data and the following tentative structure was proposed .
Both of pure flavonoid and the crude extract of theleaves were subjected to antibacterial activity . The crude
product was found to be potent aginst : Echerichia coli, Staphylocousaureus ,Bacillus subtile , Sallomenatyphia , Aspergillusniger , Candidealbacan. However the pure flavonoid showed weak antibacterial activity .