Isolation of flavonoid extract from Georgian Citrus sinensis (Seike navel) peel and some of its properties

Author: Nika Atanelov
Co-authors: Nana Koshoridze, Giorgi Burjanadze, Giorgi Kuprava, Nino Arutinashvili
Keywords: Flavonoids, Psycho-emotional stress, Antioxidant system, Energy metabolism
Annotation:

Stress is an integral part of modernity that induces several adaptive, behavioral and physiological responses to retrieve homeostasis in biological system. It is known that basis of alterations induced by stress are mainly linked to intracellular biochemical processes that are reflected in changes of hormonal status, quantitative changes of signaling molecules, depletion of energy metabolism, decrease of antioxidant properties of cells, reduction of enzymatic activity and changes in transcriptional and translational intensivity and other important processes that can induce several pathologies and diseases. Consequently, the modern scientific society is focused on finding substances that are capable of preventing stress. At this point it is noteworth mentioning Flavonoids - compounds with literally proven antioxidant properties. Hence, the goal of the present study was to investigate potentially preventive properties of flavonoids towards oxidative processes and chronic psycho-emotional stress in the blood and cardiac muscle cells of white laboratory rats, induced by long-term social isolation and deprivation of natural cyrcadian rhythm. Isolation of polyphenol extract with significant amounts of flavonoid compounds (Georgian orange flavonoid - GOF) from precocious Georgian Citrus sinensis peel (Citrus sinensis (L.) Osbeck “Seike Navel”, form N26) was established by multistage process based on water associated fraction (WAF). It has been shown that daily administration of GOF (7.5 mg/kg) intraperitoneally during 30 days had positive influence on altered biochemical and physiological processes in blood and cardiac muscle cell, induced by chronic psycho-emotional stress. For instance, administration of GOF tends to upregulate activity of enzymes involved in antioxidant system (SOD, Catalase). On the other hand, GOF has positive affect on lipid superoxidation, quantitative changes of blood lipit spectrum, and concentration of intracellular nitric oxide and Ca2+ ions. It is noteworthy that administration of GOF also upregulated activities of several enzymes involved in energy metabolism, respectively Succinate dehydrogenase (SDH) and Creatine kinase (CK). Additionaly, properties of Georgian orange flavonoids (GOF) were compared to commercially used flavonoid - Nobiletin, also isolated from citrus sinensis peel. In terms of some parameters, GOF revealed better biological activity than Nobiletin.

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Bachelor's thesis_Atanelov [ka]