Purpose:
To investigate the essential oil content of
Clausena suffruticosa
leaf for its in-vitro
antibacterial, antifungal and cytotoxic activities.
Methods:
The essential oil of
Clausena suffruticosa leaf was extracted by hydrodistillation using a
modified Clevenger-type apparatus and was analyzed by GC-MS using electron impact ionization
method. Antibacterial, antifungal and cytotoxic screenings were made by disc diffusion technique,
poisoned food technique and brine shrimp lethality bioassay, respectively. Minimum inhibitory
concentration (MIC) of the oil was determined by measuring the zone of inhibition, with tetracycline as
reference standard. Fluconazole served as standard in the antifungal assessment.
Results:
A total of twenty two compounds, of which Estragole, Anethole and β-Ocimene were the major
ones, were found in the essential oil of
C. suffruticosa. The oil showed higher antibacterial activity
against
Shigella flexneri
than the reference, tetracycline (p < 0.05). Significant activity (p < 0.001)
against other Gram-positive microbes -
Staphylococcus aureus
,
Bacillus subtilis
,
Bacillus cereus
,
Bacillus polymyxa
and
Bacillus megaterium
– was also observed. However, Gram-negative bacteria -
Salmonella typhi
,
Shigella flexneri
,
Proteus mirabilis
and
Escherichia coli
.
Klebsiella pneumoniae
and
Shigella sonnei
- showed no sensitivity to the oil. In the antifungal assay, the oil exhibited greater activity
(p < 0.001) against
Aspergillus ochraceus
than the reference, fluconazole, Inhibition of other fungal
strains tested was also statistically significant (p < 0.001). The lethal concentration (LC
50) of the oil
against brine shrimp was 41.2 μg/ml in the cytotoxic assay.
Conclusion:
It is evident that the essential oil of
C. suffruticosa is a potent antimicrobial and cytotoxic
agent that should be further evaluated.
