عنوان المقالة: التقييم المختبري للتأثير المميت لمستخلص الألوفيرا والعسل ضد سلالات الأكنثاميبا In vitro amoebicidal effect of Aloe vera ethanol extract and honey against Acanthamoeba spp. cysts
Ghada Mohamed Kadry, Mousa A. M. Ismail, Nagwa Mostafa El-Sayed, Hanan S. El-Kholy & Dina M. Hamdy El- Akkad
الملخص الانجليزي
This study evaluated in vitro effect of different
concentrations of Aloe vera (A. vera) ethanol extract and
honey against Acanthamoeba spp. cysts in comparison with
chlorhexidine (the drug of choice for treatment of Acanthamoeba
infection) at different incubation periods. Four
different concentrations of the tested agents were used,
100, 200, 400, and 600 lg/ml for A. vera ethanol extract
and 25, 50, 100, and 200 lg/ml for honey. Isolated Acanthamoeba
spp. cysts from keratitis patients were incubated
with different concentrations of the tested agents as well as
chlorhexidine 0.02% (drug control) for different incubation
periods (24, 48, 72 h). After each incubation period, the
effect of A. vera extract and honey against Acanthamoeba
cysts was assessed by counting the number of viable cysts,
determining the inhibitory percentage and detecting the
morphological alternations of treated cysts compared to
non-treated and drug controls. Both A. vera ethanol extract
and honey showed a concentration and time-dependent
effect on the viability of Acanthamoeba cysts. In comparison
with chlorhexidine (the drug control), A. vera ethanol
extract possessed a potent cysticidal activity at all tested
concentrations throughout different incubation periods,
except for concentration 100 lg/ml which recorded the
lower inhibitory effect. With increasing the dose of A. vera
ethanol extract to 200, 400, 600 lg/ml, the recorded inhibitory
percentages of Acanthamoeba cysts viability were
82.3%, 92.9% and 97.9% respectively, after 72 h compared
to 76.3% of chlorhexidine. Similarly, honey at concentrations
of 50–100 lg/ml gave higher inhibitory effect of 59%
and 76.7%, respectively compared to chlorhexidine which
showed an inhibitory percentage of 55.7% after 24 h.
Meanwhile, the lowest tested concentration of honey
(25 lg/ml) gave an inhibitory effect by 47.7–67% which
was less than that of chlorhexidine throughout different
incubation periods. With increasing the dose of honey to
200 lg/ml, the inhibitory effect was 98.9% after 72 h
higher than that of chlorhexidine (76.9%). Using a scanning
electron microscope, Acanthamoeba cysts treated by
A. vera ethanol extract showed alternations in their shapes
with flattening, collapsing, and laceration of their walls.
Also, treated cysts by honey were highly distorted and
difficult to identify because most of them were shrinkage
and collapsed to a tiny size. On the other hand, chlorhexidine
showed less structural and morphological changes of
Acanthamoeba cysts. A. vera ethanol extract and honey had
considerable cysticidal effects on Acanthamoeba cysts.
They may give promising results for treatment of Acanthamoeba
keratitis.
ا.د. نجوى مصطفى السيد | Prof. Nagwa Mostafa El-Sayed | 3864