Now showing 1 - 8 of 8
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Publication

Effect of the Addition of Extractives on The Reduction Of Vocs Emissions from Lacquers in the liquid state

2023, Brózdowski, Jakub, Gajewski, Erik, Szczepaniak, Oskar, Stachowiak-Wencek, Agata

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May DNA analyses be biased by hidden oxidative damage? Voltammetric study of temperature and oxidation stress effect

2024, Szczepaniak, Oskar, Ligaj, Marta

The analysis of nucleic acids is one of the fundamental parts of modern molecular biology and molecular diagnostics. The information collected predominantly depends on the condition of the genetic material. All potential damage induced by oxidative stress may affect the final results of the analysis of genetic material obtained using commonly used techniques such as polymerase chain reaction or sequencing. The aim of this work was to evaluate the effects of high temperature and pH on DNA structure in the context of the occurrence of oxidative damage, using square-wave voltammetry and two independent research protocols. We resulted in visible oxidation damage registered in acidic conditions after the thermal denaturation process (pH 4.7) with changes in the intensity of guanine and adenine signals. However, using phosphate buffer (pH 7.0) for DNA denaturation negatively affected the DNA structure, but without any oxidized derivatives present. This leads to the conclusion that oxidation occurring in the DNA melting process results in the formation of various derivatives of nucleobases, both electrochemically active and inactive. These derivatives may distort the results of molecular tests due to the possibility of forming complementary bonds with various nucleobases. For example, 8-oxoguanine can form pairs with both cytosine and adenine.

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Publication

Docking analysis of phenolic acid and flavonoids with selected TAS2R receptors and in vitro experiment

2024, Szczepaniak, Oskar, Jokiel, Maria, Stuper-Szablewska, Kinga, Kobus-Cisowska, Joanna

AbstractCornelian cherry fruits contain a wide range of phenolic acids, flavonoids, and other secondary metabolites. Selected flavonoids may inhibit the perceiving of bitterness, however, the full mechanism with all TAS2R bitter taste receptors is not known. The aim of the study was to determine the inhibitory effect of Cornus mas phenolics against the bitterness receptors TAS2R13 and TAS2R3 through functional in vitro assays and coupling studies. The overall effect was validated by analysing the inhibition of the receptors activity in cells treated with tested cornelian cherry extracts. The strength of interaction with both TAS2R receptors varied between studied compounds with different binding affinity. Most compounds bonded with the TAS2R3 receptor through a long-distant hydrophobic interaction with Trp89A and π–π orbital overlapping—between phenolic and tryptophane aromatic rings. For TAS2R13 observed were various mechanisms of interaction with the compounds. Nonetheless, naringin and quercetin had most similar binding affinity to chloroquine and denatonium—the model agonists for the receptor.

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Dataset

Interaction of flavonoids and phenolic acids with DNA

2022, Szczepaniak, Oskar

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Publication

Cornelian cherry fruits as a source of compounds that protect proteins from oxidative stress

2024, Szczepaniak, Oskar

Cornelian cherry fruits are rich in vitamin C, phenolics and other compounds shaping their high antioxidant profile. The study aimed to assess the cornelian cherry extract effect on the inhibition of protein oxidation. Observed was moderate inhibitory effect of the extract and antiradical activity against ABTS. However, both studied effects rather result from other bioactive compounds than the flavonoids.

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Publication

The use of attractants in reducing the occurrence of the Prunus serotina (Ehrh.)

2023, Baranowska, Marlena, Szczepaniak, Oskar, Meres, Bartłomiej, Korzeniewicz, Robert, Uniwersytet Przyrodniczy w Poznaniu

Abstract Black cherry, which occurs in European forests, contributes to their distortion or degradation of native ecosystems. Therefore, measures are taken to reduce its occurrence. One of them is the biological method involving grazing animals. The aim of this research was to develop and identify an attractant that would increase the attractiveness of black cherry as a feeding base for deer, which would limit its occurrence. This research was carried out in Zielonka (17.10941 E 52.553975 N). In the experiment, 3-year-olds were used: Tilia cordata, Acer pseudoplatanus, A. platanoides, Fagus sylvatica and Prunus serotina. Before planting the seedlings, their height was measured. The control (K, 10 trees) consisted of trees of each species that were not sprayed with attractants. Another set of 10 trees were treated over the entire surface of the shoots with a bait mixture (MW), and the next 10 trees were sprayed with a 10% aqueous solution of NaCl. The attractant spraying was repeated six times. All damage observed was recorded. The inventoried tree damage was divided into four categories: 0%, no damage; I, 1–20% damaged trees; II, 21–50% damaged trees and III, more than 50% damaged trees. The results of the Mann–Whitney U test (p = 0.0109), at the assumed level of significance (α = 0.05), showed that slightly higher seedlings were browsed. These studies indicate the potential of using attractants as preparations influencing the palatability of the black cherry for deer. All recorded bites were classified as degree I damage. The trees were gnawed by fallow deer, 35.33% of trees were not damaged by game at all, and 64.66% of trees were damaged in degree I. In the case of sycamore maple, Norway maple and linden, the bait mixture did not increase the number of nibbled buds and leaves, while NaCl increased the attractiveness of beech and black cherry as a feeding base. Conducting further research studies on the improvement of preparations may give a chance to reduce the use of chemicals in forest protection and give the possibility of using attractants where it is impossible to use herbicides.

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Publication

The Contribution of Cornelian Cherry (Cornus mas L.) Alcoholic Beverages on the Sensory, Nutritional and Anti-Nutritional Characteristics—In Vitro and In Silico Approaches

2024, Szczepaniak, Oskar, Stachowiak, Barbara, Jeleń, Henryk, Stuper-Szablewska, Kinga, Szambelan, Katarzyna Teresa, Kobus-Cisowska, Joanna

Food producers have focused on novel and attractive raw materials with functional properties. Cornelian cherry (Cornus mas L.) fruits contain numerous compounds that may be beneficial for health. Objective: This study aimed to compare and assess the physicochemical properties and amygdalin levels in brandy and liquor prepared from frozen cornelian cherry fruits. Density functional theory-based B3LYP functionals were used to analyze the spectral and optical properties of amygdalin. The contents of the compounds and volatile products of amygdalin decay were found in two spirituose beverages of Cornus mas, using HPLC and GC-MS. Significant differences in their physicochemical properties were detected between the samples. Alcoholic beverages based on cornelian cherry fruits were rich in a wide range of functional ingredients with a low concentration of amygdalin. In silico analysis showed that orbital density diffusion has a major effect on the physical properties of amygdalin, while differences between the polarities of water and ethanol had no noticeable effect on the spectral properties of the compound. Cornelian cherry-based alcoholic drinks might be interesting functional products with rich aromatic bouquets. The amygdalin concentration is low enough to pose no toxicological threat, but rather shapes the tastory bouquet of the products. Levels of amygdalin may be controlled using the same analytical methods for solutions with different ethanol–water ratios.

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Patent

Sposób wytwarzania chleba mieszanego z leżakowanymi liśćmi morwy białej, w szczególności dla diabetyków

2024, Przeor, Monika Teresa, Kobus-Cisowska, Joanna Magdalena, Kmiecik, Dominik, Szczepaniak, Oskar, Beszterda-Buszczak, Monika Krystyna