Page 133 - Book of Abstracts

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

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IN VITRO STUDIES OF ANTIOXIDANT POTENTIAL OF EXTRACT DERIVED FROM THE
LEAVES OF BEGONIA FOLIOSA KUNTH IN HUMAN ERYTHROCYTE SUSPENSION
2
Halyna Tkachenko , Lyudmyla Buyun , Natalia Kurhaluk , Maryna Opryshko ,
1
1
2
Myroslava Maryniuk , Oleksandr Gyrenko
2
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
The current study describes the effect of aqueous leaf extracts obtained from Begonia
foliosa Kunth with human erythrocytes suspension. Erythrocytes were chosen because
although less specialized than many other cell membranes they carry on enough functions in
common with them, i.e. active and passive transport, the production of ionic and electric
gradients, etc. Therefore, their structure can be considered representative of the plasma
membrane in general. Thus, 2-thiobarbituric acid reactive substances (TBARS) as a biomarker
of lipid peroxidation, aldehydic and ketonic derivatives of oxidatively modified proteins (OMP),
and total antioxidant capacity (TAC) have been used in order to assess oxidative stress in
erythrocytes' suspension after incubation with plant extract in dose 5 mg/mL.
The leaves of Begonia foliosa plants, cultivated under glasshouse conditions, were
sampled at M.M. Gryshko National Botanical Garden (NBG), National Academy of Science (NAS)
of Ukraine. Freshly collected leaves of B. foliosa were washed, weighed, crushed, and
homogenized in 0.1M phosphate buffer (pH 7.4) (in ratio 1:19, w/w) at room temperature. All
extracts were stored at -20 °C until use. Human blood (10-20 ml) was obtained from normal
volunteers via venipuncture. The Research Ethics Committee of Medical University in Gdańsk
(Poland) approved the study (KB-31/18). Human erythrocytes were isolated by centrifugation
at 3,000 rpm for 10 min and washed two times with 4 mM phosphate buffer (pH 7.4). An
erythrocyte suspension at 1 % hematocrit was incubated with 4 mM phosphate buffer (pH 7.4)
(control) and pre-incubated with the extract (5 mg/mL) at 37 °C for 60 min. This reaction
mixture was shaken gently while being incubated for a fixed interval at 37 °C. For positive
control, phosphate buffer was used.
The results obtained by incubating human erythrocyte suspension in the presence of the
aqueous extract derived from the leaves of B. foliosa revealed a significant decrease of TBARS
level (by 69.5 %, p <0.05), while the content of aldehydic and ketonic derivatives of oxidatively
modified proteins was non-significantly decreased (by 14.2 and 9.5 %, p >0.05) compared to
control samples. The maintenance of oxidative stress biomarkers on the persistent level
induced the non-statistically significant decrease in the total antioxidant capacity level (by 23.4
%, p >0.05). In conclusion, extract derived from the leaves of B. foliosa possessed antioxidant
defenses potential decreasing lipid peroxidation level in the human erythrocytes. These in vitro
assays indicate that B. foliosa extract screened is a significant source of natural antioxidants,
which might help prevent the progress of various oxidative stress-induced pathological
disorders. In particular, it was revealed that the antioxidant and antimicrobial activity of
B. trichocarpa Dalzell is associated with the presence of flavonoid quercetin. However, the
phytoconstituents responsible for the antioxidative activity of B. foliosa extract have not yet
been found. Therefore, further investigations need to be carried out to isolate and identify the
phytochemical constituents and antioxidant compounds present in the B. foliosa plant extract,
including high-performance liquid chromatography-mass spectrometry (HPLC-MS)-based
profiling.
Keywords: Begonia foliosa, leaves, lipid peroxidation, total antioxidant capacity, erythrocytes.

Acknowledgments
We are grateful to The Polish National Commission for UNESCO for supporting our study.

5 International Scientific Conference Agrobiodiversity for Improving the Nutrition, Health, Quality of Life and |132
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Spiritual Human Development
November 3 2021
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