Abstract:
The aim of this study was to study the antibacterial activity of the
different concentrations of n-hexene, methanol and aqueous extracts of the
medicinal plants Psidium guajava leaves and Carthamus tinctorius seeds
using agar dilution method.
Hundred wound swabs were collected from patients with infected wounds
who attended Khartoum Teaching Hospital during the period from April to
June 2013.
The n-hexene, methanol and aqueous extracts of Psidium guajava leaves
(family Myrtaceae), and Carthamus tinctorius seeds (family Asteraceae) were
screened for their antimicrobial activity against standard bacteria; one Gram
positive (Staphylococcus aureus, ATCC 25923) and three Gram negative
(Klebsiella pneumoniae ATCC 53657, Pseudomonas aeruginosa ATCC 27853
and E.coli ATCC 25922). These extracts were also screened against clinical
isolates of S.aureus, K.pneumoniae, P.aeruginosa and E.col.
Methanol extracts of Psidium guajava leaves and Carthamus tinctorius
seeds were more active against one or more of the four bacteria ( S.aureus,
E.coli, K.pneumoniae and P.aeruginosa). The aqueous extract of Psidium
guajava leaves inhibits one or more of four tested bacteria. However the
aqueous extract of Carthamus tinctorius seeds exhibited no activity against
all tested bacteria and the n-hexene extract of two plants also showed no
activity against all the tested bacteria.
The antibacterial activity of five reference drugs; gentamicin,
erythromycin, amoclan, ciprofloxacin and tetracycline were determined
against the standard and clinical isolated bacteria and their activity was
compared to the activity of plants' extracts.
Gas chromatography analysis exhibited 23 compounds of Psidium guajava
leaves and also these compounds are identified qualitatively by the Retention
time, and quantitatively by the area under the curve.
