Page 128 - Book of Abstracts

5 International Scientific Online Conference DOI: https://doi.org/10.15414/2021.9788055224015

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IN VITRO ANTIBACTERIAL ACTIVITY OF THE CRUDE ETHANOLIC EXTRACTS FROM THE
LEAVES OF SOME BEGONIA SPP. AGAINST ENTEROCOCCUS FAECALIS ISOLATE
Halyna Tkachenko , Lyudmyla Buyun , Natalia Kurhaluk , Yana Belayeva
1
2
1
2
1 Institute of Biology and Earth Sciences, Pomeranian University in Słupsk, Poland;
E-mail.: halyna.tkachenko@apsl.edu.pl
2 M.M. Gryshko National Botanic Garden, National Academy of Science of Ukraine, Kyiv, Ukraine
Begonia is now considered to be one of the five largest genera of vascular plants, and the
genus is increasingly used as a model for understanding the evolution of species-rich genera.
Moreover, phytochemical screening of Begonia species has revealed that many compounds,
isolated from these plants are highly bioactive. Considering that the therapeutic efficiency of
antimicrobials has become more complex due to the emergence of multidrug resistance, in the
present study, we aimed to evaluate the antimicrobial effects of ethanolic extracts obtained
from leaves of nine Begonia species against the Enterococcus faecalis (Andrewes and Horder)
Schleifer and Kilpper-Balz ATCC 51299™ strain using Kirby-Bauer agar disc diffusion assay.
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The leaves of Begonia plants, cultivated under glasshouse conditions, were sampled at
M.M. Gryshko National Botanical Garden (NBG), National Academy of Science of Ukraine. The
list of Begonia species, selected for this study includes Begonia solimutata L.B. Sm. & Wassh.,
Begonia goegoensis N.E.Br., Begonia foliosa Kunth, Begonia × bunchii L.H.Bailey (syn. Begonia ×
erythrophylla Hérincq), Begonia thiemei C.DC. (syn. Begonia macdougallii Ziesenh.), Begonia
peltata Otto & Dietr. (syn. Begonia kellermanii C.DC.), Begonia heracleifolia Cham. & Schltdl.,
Begonia dregei Otto & Dietr., Begonia mexicana G. Karst. ex Fotsch. Fresh leaves were washed,
weighed, crushed, and homogenized in 96 % ethanol (in proportion 1:19) at room temperature.
The extracts were then filtered and investigated for their antimicrobial activity. Strain tested
was plated on TSA medium (Tryptone Soy Agar) and incubated for 24 hr at 37 °C. Then the
suspension of microorganisms was suspended in sterile PBS and the turbidity adjusted
equivalent to that of a 0.5 McFarland standard. The antimicrobial susceptibility testing was
done on Muller-Hinton agar by the disc diffusion method (Kirby-Bauer disk diffusion
susceptibility test protocol). Muller-Hinton agar plates were inoculated with 200 µl of
standardized inoculum (10 CFU/mL) of the bacterium and spread with sterile swabs. Zone
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diameters were determined and averaged.
The current study has shown that ethanolic extracts obtained from leaves of Begonia
plants possessed moderate activity against E. faecalis. The diameters of the inhibition zone
were (14.87 ±0.87) mm for B. solimutata, (14.26 ±0.91) mm for B. goegoensis, (13.78 ±1.02) mm
for B. foliosa, (11.55 ±1.05) mm for Begonia × bunchii, (11.18 ±0.99) mm for B. thiemei, (12.58
±1.12) mm for B. peltata, (13.2 ±1.04) mm for B. heracleifolia, (14.61 ±1.17) mm for B. dregei,
and (14.53 ±1.20) mm for B. mexicana. The highest antimicrobial effect was recorded for B.
solimutata, B. dregei, B. goegoensis, and B. mexicana. The most antimicrobial effective plant
against E. faecalis was B. solimutata, being more active with the ethanolic extract (diameter of
inhibition zone was 14.26 ±0.91 mm).
The results of the current study provide informative data for the use of the crude ethanolic
extracts obtained from leaves of some Begonia species against bacterial microbial infections
caused by E. faecalis. According to our results, the leaf extract of B. solimutata, B. dregei, B.
goegoensis, and B. mexicana exhibited significant anti-E. faecalis effects. Therefore, these plants
could serve as source materials for the development of new antimicrobial agents. However,
further phytochemical research focused on these species will be needed to isolate and
characterize their antimicrobial effective constituents.
Keywords: Begonia, leaves, ethanolic extract, antimicrobial activity, agar disk diffusion assay.

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5 International Scientific Conference Agrobiodiversity for Improving the Nutrition, Health, Quality of Life and |127
Spiritual Human Development
November 3 2021
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