Genoprotective effect of cornelian cherry (Cornus mas L.) phytochemicals, electrochemical and ab initio interaction study.

Cornelian cherry (Cornus mas L.) has broad and multidimensional potential in preventing civilisational diseases. Part of these diseases results from DNA oxidative mutations. Thus, the paper aimed to predict how phenolics present in C. mas may interact with dsDNA in ab initio experiment and to check the effect of different cornelian cherry extracts on DNA structure and DNA oxidation. A special research model was designed using biosensor with a carbonpaste electrode. We resulted in various effects observed for phenolics and the extracts. Flavonoids, but of vitexin interacted with declining energy of the DNA models and liability of DNA oxidation. However, for 8-oxoguaniosine the trend was the opposite. Among the evaluated extracts, water-ethanolic extracts caused decline in adenine and guanine signals after dsDNA exposition on the extract. Principal component analysis showed that alcoholic extracts of cv. Szafer and Slowianin, which were rich in apigenin and kaempferol exhibit mild genoprotective effect.

The Genoprotective Role of Naringin.

Since ancient times, fruits and edible plants have played a special role in the human diet for enhancing health and maintaining youthfulness. The aim of our work was to determine the interactions between naringin, a natural ingredient of grapefruits, and DNA using an electrochemical biosensor. Electrochemical methods allow analyzing the damages occurring in the structure of nucleic acids and their interactions with xenobiotics. Our study showed that the changes in the location of electrochemical signals and their intensity resulted from the structural alterations in DNA. The signal of adenine was affected at lower concentrations of naringin, but the signal of guanine was unaffected in the same condition. The dynamics of changes occurring in the peak height and surface of adenine related to naringin concentration was also significantly lower. The complete binding of all adenine bases present in the tested double-stranded DNA solution was observed at naringin concentrations ranging from 8.5 to 10.0 µM. At larger concentrations, this active compound exerted an oxidizing effect on DNA. However, the critical concentrations of naringin were found to be more than twice as high as the dose absorbable in an average human (4 µM). The results of our work might be helpful in the construction of electrochemical sensors for testing the content of polyphenols and would allow determining their genoprotective functionality.

Application of DNA Hybridization Biosensor as a Screening Method for the Detection of Genetically Modified Food Components.

An electrochemical biosensor for the detection of genetically modified food components is presented. The biosensor was based on 21-mer single-stranded oligonucleotide (ssDNA probe) specific to either 35S promoter or nos terminator, which are frequently present in transgenic DNA cassettes. ssDNA probe was covalently attached by 5'-phosphate end to amino group of cysteamine self-assembled monolayer (SAM) on gold electrode surface with the use of activating reagents - water soluble 1-ethyl-3(3'- dimethylaminopropyl)-carbodiimide (EDC) and N-hydroxy-sulfosuccinimide (NHS). The hybridization reaction on the electrode surface was detected via methylene blue (MB) presenting higher affinity to ssDNA probe than to DNA duplex. The electrode modification procedure was optimized using 19-mer oligoG and oligoC nucleotides. The biosensor enabled distinction between DNA samples isolated from soybean RoundupReady® (RR soybean) and non-genetically modified soybean. The frequent introduction of investigated DNA sequences in other genetically modified organisms (GMOs) give a broad perspectives for analytical application of the biosensor.