Pseudomonas aeruginosa is a common opportunistic pathogen of respiratory tract
and cause both hospital and community acquired infections. For the treatment of
infections antibiotics are used but due to random selection of commonly used antibiotics,
resistance in P. aeruginosa has developed. This problem may leads to the high morbidity
and mortality rate. Different medicinal plants have antibacterial activity in their
secondary metabolite. Secondary metabolites are terpens, flavonoids, alkaloids and
alcohols etc. So the plant extract could be the alternative therapy for the treatment to
reduce the antibiotic resistance problem.
Isolates of P. aeruginosa was procured from the main clinical laboratory of Mayo
Hospital, Lahore and identified biochemically according to bergey’s manual of
determinative bacteriology. Antibiotic resistance pattern of identified P. aeruginosa was
evaluated by Kirby Bauer disc diffusion assay against selected antibiotics includes
ciprofloxacin, levofloxacin, meropenem and imipenem. Measure the zone of inhibition
and isolates marked as resistant, intermediate and sensitive. Resistant strains were
alienated for further evaluation.
Leaves of Eucalyptus globulus (Tasmanian blue gum) and Calotropis procera
(apple of Sodom) proceed for extraction and the plant extracts was obtained by using
solvent chloroform and ethanol. Percentage yield of both plant extract was calculated.
High percentage yield was obtained from Eucalyptus globulus and less percentage yield
was gained from Calotropis procera in comparison The obtained extract was dried and
the resultant material was used in well diffusion assay to evaluate the antibiotic
CHAPTER 6
SUMMARY
Summary
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sensitivity of resistant P. aeruginosa against selected plants. Stock of plant extracts was
prepared by dissolving 1g of plant extract in 1ml of DMSO. Well diffusion assay was
performed and zones were measured in millimeter and categorized as resistant, sensitive
and intermediate. Isolates that are susceptible to plant extracts were separated and
Minimum inhibitory concentration of susceptible isolates was determined by broth micro
dilution assay and cytotoxicity profiling was done by 3-(4, 5-dimethyl-2-thiazolyl)-2,5-
diphenyl-2H-tetrazolium bromide (MTT) assay and cell survival percentage was
calculated.
Data recorded during the study was analyzed by one-way analysis of variance
(ANOVA) followed by Duncan’s test using the SPSS statistical software program.
Differences were considered significant at P < 0.05.