Page 35 - Book of Abstracts

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

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OXIDATIVE STRESS BIOMARKERS IN THE HUMAN ERYTHROCYTE SUSPENSIONS
EXPOSED TO EXTRACTS OBTAINED FROM COELOGYNE ASPERATA LINDL. LEAVES
1
2
Lyudmyla Buyun , Halyna Tkachenko , Natalia Kurhaluk , Maryna Opryshko ,
2
1
Myroslava Maryniuk , Oleksandr Gyrenko
1
1
1 M.M. Gryshko National Botanic Garden, National Academy of Science of Ukraine, Kyiv, Ukraine;
E-mail.: buyun@nbg.kiev.ua
2 Institute of Biology and Earth Sciences, Pomeranian University in Słupsk, Poland
In the current study, crude water extracts derived from the leaves of epiphytic orchid
Coelogyne asperata Lindl. were assessed for antioxidant activities using the oxidative stress
biomarkers (2-thiobarbituric acid reacting substances) as a biomarker of lipid peroxidation,
carbonyl derivatives as biomarkers of protein oxidative modification) in the human erythrocyte
model.
The leaves of Coelogyne asperata cultivated under glasshouse conditions were sampled at
M.M. Gryshko National Botanical Garden (Kyiv, Ukraine). Freshly collected leaves were washed,
weighed, crushed, and homogenized in 0.1M phosphate buffer (pH 7.4) at room temperature.
Blood (10–20 ml) was obtained from normal volunteers via venipuncture. An erythrocyte
suspension at 1 % hematocrit was incubated with 4 mM phosphate buffer (pH 7.4) (control)
and pre-incubated with the extracts (0.5 and 5 mg/mL) at 37 °C for 60 min. For positive control,
phosphate buffer was used. The level of lipid peroxidation was determined by quantifying the
concentration of 2-thiobarbituric acid reacting substances (TBARS) with the Kamyshnikov
(2004) method. The rate of protein oxidative destruction was estimated from the reaction of
the resultant carbonyl derivatives of amino acid reaction with 2,4-dinitrophenylhydrazine
(DNFH) as described by Levine et al. (1990) and as modified by Dubinina et al. (1995).
The extract influence during incubation with erythrocyte suspension in a dose of 0.5
mg/mL caused a non-considerable decrease of TBARS level (by 11.6 %, p>0.05), while extract
in dose 5 mg/mL induced lipid peroxidation (increased TBARS level by 15.5 %, p<0.05)
compared to the control samples. Content of aldehydic derivatives of oxidatively modified
proteins was increased after treatment by extracts in doses of 0.5 and 5 mg/mL (by 6.9 %,
p>0.05, and 26 %, p<0.05, respectively) compared to control samples. On the other hand,
ketonic derivatives of oxidatively modified proteins were decreased after treatment by extracts
in doses of 0.5 and 5 mg/mL (by 6.3 %, p>0.05, and 5.8 %, p>0.05, respectively) compared to
control samples.
The results of the current research indicated that crude extract obtained from C. asperata
leaves in a dose of 0.5 mg/mL possessed an effective antioxidant effect after the treatment of a
suspension of human erythrocytes. The protective effect of C. asperata extract is evident by the
suppression of lipid peroxidation biomarker (TBARS level), as well as ketonic derivatives of
oxidatively modified proteins. Extract of C. asperata leaves in a dose of 5 mg/mL exhibited
prooxidative effect increasing lipid peroxidation and protein oxidation. It should be taken into
consideration that the potential antioxidant function of a plant extract in vivo cannot be directly
extrapolated from in vitro assays, since they do not take into account the metabolic
transformations and interactions that affect the bioavailability and biological action of
polyphenols.
Keywords: Coelogyne asperata, leaves, lipid peroxidation, 2-thiobarbituric acid reactive substance,
erythrocytes.
Acknowledgments
This study was carried out during the Scholarship Program supported by The Visegrad Fund in the
Institute of Biology and Earth Sciences, Pomeranian University in Słupsk (Poland). We thank The
Visegrad Fund for supporting our study.

5 International Scientific Conference Agrobiodiversity for Improving the Nutrition, Health, Quality of Life and |34
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Spiritual Human Development
November 3 2021
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