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  • Küçük Resim Yok
    Öğe
    Comparison of Chemical Contents of Extracts in Different Solvents of Propolis Samples Produced in Duzce Province
    (Düzce Üniversitesi, 2020) Dönmez, Mert; Karadeniz, Şeref; Yoldas, Taner; Aydın, Gülşah; Karagül, Pınar; Aksu, Osman; Göç Rasgele, Pınar
    Objective: Although the volatile components in the propolis composition are in very low concentration, they are extremely important for the characterization of propolis due to their aroma-giving properties and various biological activities. Since propolis is a product obtained from plants, its chemical composition depends on the local plant flora and the geographical and climatic characteristics of the region where the sample is collected. Therefore, different propolis samples can differ completely in terms of their chemistry and biological activities. Propolis extracts obtained by using different solvents have different contents. For this reason, the content of antioxidants varies, which causes differences in phenolic and flavonoid amounts. In the study, it was aimed to determine the efficacy of different propolis extracts produced as a result of beekeeping activities in Düzce province by comparing the chemical content. Material-Method: The extracts of propolis collected from Düzce province were prepared using ethanol, water and PEG400 – water solvents. In the study carried out, the volatile components of three different extracts of propolis samples obtained from hives belonging to Yığılca Region were examined with LC-MS/MS, GC-MS UV. The determination of the total phenolic component (TPC) level was carried out with the Folin-Ciocalteu reagent, and the total flavonoid content (TFC) level with the AlCl3 based method.Results: Major volatile constituents of Ethanolic extract; Diphenyl-1,2,5-oxadiazole (86.11%) and Benzenepropanoic acid ethyl ester (6.3%), Major volatile components of PEG400-water (50% - 50%) extract; 4-vinyl-2-methoxy-phenol (40.40%), Benzyl benzoate (17.16%), Methyl benzyl ketone (16.87%) ve Ethyl 3-methylnaphtho[1,2-c]pyrrole-1-carboxylate (14.32%), major volatile components of water extract; Benzyl Alcohol (79.91%) ve 4-vinyl-2-methoxy-phenol (8.86%). The highest TPC level was in ethanolic extract with 23,192.45 ± 396.54 mgGAE/100 g. Similarly, the highest TFC was found in ethanolic extract (7,190.12 ± 203.85 mgQE/100g). The water extract had the lowest levels at both TPC and TFC levels.Conclusion: It has been concluded that the highest phenolic content of propolis, which has recently begun to find an important use in the food and health sector, is obtained by ethanol extraction. When evaluated in terms of the obtained results from all methods, it is listed as Etanolic extract> PEG400> water extract. Further studies should be done using different solvents in order to extract as much of the components from propolis as possible.
  • Küçük Resim
    Öğe
    Effects of Some Adsorbents on the Pre-purification of Taxol (Anticancer Drug) from Hazelnut Nutshells
    (Asian Network Scientific Information-Ansinet, 2018) Oğuzkan, Sibel Bayıl; Karadeniz, Şeref; Karagül, Bora; Uzun, Ayşe; Aksoy, Elif Sine; Güler, Özen Özensoy; Uğraş, Halil İbrahim
    Background and Objective: The most important pharmaceutically active substance in plant-derived chemotherapy drugs is paclitaxel. Taxane compounds such as paclitaxel, cephalomannine, baccatin III and 10-Deacetylbaccatin III are found in hazelnut shells of Turkey's Black Sea region. This study aimed to determine the most effective adsorbent on the purity and efficiency of these taxane compounds from nutshells. Materials and Methods: The adsorbent effect on the purification of taxane compounds from hazelnut shells was studied using different adsorbent materials. For this purpose, extracts were obtained from samples of hazelnut shells collected, dried and ground into solvents. The resulting extract was concentrated into a stock solution. Samples taken from the stock solution were separately treated with seven different adsorbent materials and then filtered and analyzed with HPLC (High Performance Liquid Chromatography). Results: The HPLC analysis of taxane compounds determined on taxane, both the purification and whether or not the substance was lost, by measuring the efficiency at the same time. Graphene-oxide was found to be the adsorbent with the highest positive effect on the purification of paclitaxel in hazelnut nutshells in all cases. Graphene-oxide also had the least loss in terms of paclitaxel yield efficiency in hazelnut nutshells. Conclusion: The effects of adsorbent treatment increased both the purity and efficiency of taxane compounds and was, thus, a useful pre-purification method for shells obtained from Turkish hazelnuts. This shell waste material may prove to be a good alternative source of taxol as an anticancer drug.