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Öğe Bee bread and bee pollen of different plant sources: determination of phenolic content, antioxidant activity, fatty acid and element profiles(Springer, 2020) Mayda, Nazli; Ozkok, Asli; Ecem Bayram, Nesrin; Gercek, Yusuf Can; Sorkun, KadriyeThis study aims to determine the plant sources, fatty acid composition, total phenolic-flavonoid content, antioxidant capacity, and elemental profile of bee pollen (BP) and bee bread (BB) samples from the same bee hive in different locations. 31 families and 71 species were determined by pollen analysis of BP and BB samples. Pollen frequencies in BB samples were generally similar or less than in BP. Total phenolic varied from 8.26 +/- 0.299 to 43.42 +/- 0.779 mg GAE/g, and total flavonoid ranged from 1.81 +/- 0.040 to 4.44 +/- 0.125 mg QE/g. ABTS and DDPH assays indicated that the samples have good antioxidant activity. Samples showed a protein content ranging from 17.6 to 22.2% while the total fatty acid was between 60.27 and 86.49%. The elemental analysis showed that all samples were rich in essential minerals. As a result, total protein, total fatty acids, moisture content and antioxidant capacity of BB samples were found to be lower than those of BP samples from the same hive. In spite of these data, it is necessary to work with more detailed and more samples to be able to say which bee product (bee pollen or bee bread) has superior properties as functional food.Öğe Bee bread from Anatolia: its chemical composition, phenolic and aromatic profiles, and antioxidant properties(Taylor & Francis Ltd, 2024) Kolayli, Sevgi; Okumus Yukunc, Gulsah; Kara, Yakup; Demir Kanbur, Esra; Can, Zehra; Ozkok, Asli; Tanugur Samanci, Asli ElifThis study investigated the botanical origin, chemical composition, phenolic and volatile aromatic profiles, and antioxidant activities of 11 bee bread samples from different regions of Anatolia, Turkey. The bee bread samples contained high amounts of proteins (19.61 g/100 g) and lipids (6.43 g/100 g). The bee breads were determined to have a rich mineral content. The antioxidant potential of the bee breads was predicted using total phenolic content (TPC), total flavonoid content (TFC), total condensed tannin (TCT) content, 2,2-diphenyl-1-picrylhydrazyl (DPPH), and ferric reducing antioxidant power (FRAP) assays. The TPC of the bee breads ranged between 2.041 +/- 0.170 and 3.224 +/- 0.006 mg GAE/g, while the TFC ranged from 0.323 +/- 0.004 to 1.903 +/- 0.017 mg QE/g. The FRAP assay showed antioxidant activity ranging from 17.778 +/- 0.207 to 49.752 +/- 0.856 mu mol FeSO4.7H2O/g, and the DPPH values were between 1.054 +/- 0.009 and 4.366 +/- 0.014 SC50 mg/mL. Using 25 standards, RP-HPLC-PDA quantified the composition of the phenolic compounds, attributed to their antioxidant activity. The highest concentrations were detected for t-cinnamic acid, rutin, and p-coumaric acid. One hundred nineteen volatile aromatic compounds were determined in the bee breads by solid-phase microextraction coupled with gas chromatography and mass spectrometry (SPME-GC-MS). The obtained values suggest that bee breads could serve as a potential source of nutrients and bioactive compounds for value-added food supplements and functional foods.Öğe Honey: Determination of volatile compounds, antioxidant and antibacterial activities(Czech Academy Agricultural Sciences, 2021) Karlidag, Semiramis; Keskin, Merve; Bayram, Sinan; Mayda, Nazli; Ozkok, AsliHoney is an important functional food for human health and nutrition that is collected by honey bees and stored in the honeycombs. In this study, total phenolic content, antioxidant activity and volatile compounds of 13 different honey samples collected from various districts of Malatya province were investigated. As a result of this study, it was determined that the total phenolic content varied between 8.50 mg GAE 100 g(-1) and 73.90 mg GAE 100 g(-1) and it was observed that the honey samples were rich in aldehydes, aliphatic acid and esters, alcohols, hydrocarbons, carboxylic acid esters, ketones, terpenes, fatty acids and esters. In addition, the antibacterial effects of honey samples were determined against 18 different pathogenic bacteria using agar well diffusion (AWD) method, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). In AWD assay, it was recorded that inhibition zone diameters varied between 9 mm and 14 mm and honey samples were found to have a partial inhibitory effect against selected target pathogens.Öğe Organic acids and their derivatives: minor components of bee pollen, bee bread, royal jelly and bee venom(Springer, 2022) Celik, Saffet; Gercek, Yusuf Can; Ozkok, Asli; Bayram, Nesrin EcemThis study aimed to determine the organic acid profiles of bee products such as royal jelly, bee venom, bee pollen and bee bread, as well as to verify the method employed in the study. For this purpose, royal jelly, bee venom, bee pollen and bee bread samples were obtained from different locations, and 55 individual organic acids were determined using the liquid chromatography technique coupled with tandem mass spectrometry (LC-MS/MS), and method verification was carried out. Moreover, principal component and hierarchical cluster analyses were performed to compare the organic acid content of bee products and evaluate the overall variation. According to the results, the order of the total organic acid profiles was determined as bee venom (4141 mg/kg-6260 mg/kg) > bee bread (736-990 mg/kg) > bee pollen (837-1503 mg/kg) > royal jelly (192-1947 mg/kg). Although citric acid (423-41,519 mg/kg) was dominantly detected in samples among the organic acids screened. It is thought that the results obtained will contribute to scientific studies carried out to determine the authenticity of bee products and their standardization.Öğe Palynological, chemical, antimicrobial, and enzyme inhibition properties of Cannabis sativa L. propolis(Springer, 2023) Ozkok, Asli; Karlidag, Semiramis; Keskin, Merve; Bayram, Sinan; Keskin, Saban; Karabulut, Ercan; Cicek, FevziIn this study, both chemical characterization and biological activities of propolis samples obtained from Cannabis sativa L. (cannabis, hemp, marijuana) isolated colonies (research group) and obtained from colonies at a distance where the bee cannot fly to the isolation area (control group) were determined. Palynological analyses of propolis samples obtained from the research and control group colonies were made and the botanical origin of the cannabis plant and other plants in the research area and the plants in the control group were determined. Bioactive component analysis of propolis extracts was determined by the GC-MS technique. The inhibition effect of propolis samples on some enzymes of medical importance and their antimicrobial effects against many pathogenic microorganisms were also investigated. Palynological analyses showed that honey bees prefer cannabis plants (11.11%) when collecting propolis, and the dry matter percentage (94.6 +/- 1.8%), balsam (46.2 +/- 5.2%), and wax content (4.8 +/- 0.5%), total phenolic (26.44 +/- 1.08 mg GAE/mL) and total flavonoid (2.03 +/- 0.11 mg QE/mL) content and antioxidant capacity (88.16 +/- 2.27 mu M FeSO4 center dot 7H(2)O/mL(-1)) of the research group propolis samples containing hemp were found to be higher than the control group. Also, it was determined that the research group propolis sample contains cannabinoid derivatives (cannabidivarinic acid, 0.29%; delta (1)-tetrahydrocannabinolic acid, 0.59%; cannabidiolic acid, 0.48%), which are active compounds of the cannabis plant. Also, a high inhibition effect was detected on some enzymes of medical importance in propolis samples obtained from cannabis group colonies. In addition, the research group propolis samples also showed a high antimicrobial effect against many pathogenic microorganisms.Öğe Phenolic and free amino acid profiles of bee bread and bee pollen with the same botanical origin - similarities and differences(Elsevier, 2021) Bayram, Nesrin Ecem; Gercek, Yusuf Can; Celik, Saffet; Mayda, Nazli; Kostic, Aleksandar Z.; Dramicanin, Aleksandra M.; Ozkok, AsliIn this study, the chemical profile of bee pollen (BP) and bee bread (BB) samples collected from the same beehive were analyzed by LC-MS/MS (liquid chromatography technique coupled with tandem mass spectrometry), providing the identification of 23 phenolic compounds and 42 free amino acids (FAAs). Rutin was the phenolic compound with the highest rate of occurrence in both BP and BB samples. However, concentrations of protocatechuic acid, 2,5-dihydroxybenzoic acid and kaempferol compounds were significantly higher in BB samples than in BP samples from the same hive probably as result of microbial activity and glycosides degradation. The obtained data revealed that the phenolic profiles of the samples differ not only by the type of a product but also by region. Among FAAs proline was the predominant compound in all the analyzed BP and BB samples followed by L-asparagine (BP samples) and L-aspartic acid (BP and BB samples). A high content of proline can be used as a parameter of sample freshness. Also, Principal Component Analysis (PCA) and Cluster analysis proved the possibility of using phlorizin as a chemotaxonomic marker for Rosaceae (Malus or Prunus genus) pollen presence in BP1 sample. In addition, amino acid profile had higher impact on BP and BB sample differentiation due to lower FAAs content in BB samples probably caused by microbial activity. To the best of our knowledge, this study is the first to compare the individual phenolic compounds and free amino acids of bee pollen and bee bread samples with the same botanical origin (predominantly originated from plants belonging to the following families: Asteraceae, Fabaceae, Plantaginaceae and Rosaceae). (C) 2021 The Author(s). Published by Elsevier B.V. on behalf of King Saud University.Öğe Physicochemical Characteristics, Phenolic Components, and Antioxidant Capacities of Lavender Honey (Lavandula Spp.) from Isparta Region of Turkiye(Wiley-V C H Verlag Gmbh, 2024) Kolayli, Sevgi; Can, Zehra; Kara, Yakup; Ozkok, Asli; Ergin, Sema Ozmert; Kemal, Mehmet; Kanbur, Esra DemirLavender honey is one of the most desirable blossom honeys for its unique taste and aromatic qualities and can vary significantly from one region to another. In this study, melissopalynological, physicochemical and antioxidant properties of lavender honey from the Isparta region of T & uuml;rkiye were investigated. The ration of the Lavandula spp. pollen were identified ranging from 9 % to 76 % in the thirteen samples. The average pH, conductivity, moisture, Hunter Lab* and proline values were 3.72, 0.22 mS/cm, 17.17 %, L*: 66.56, a*: 66.32, b*:18.41 and 576.92 mg/kg, respectively. The average F+G and F/G were 67.66 % and 1.02, respectively. The average of total phenolic (TP) and flavonoid (TF) substance were found to be 39.40 mg GAE/100 g and 3.23 mg QUE/100 g, respectively. The average total antioxidant capacity (FRAP) and DPPH radical scavenging activity values were found to be 178.28 mu mol FeSO4 & sdot; 7H(2)O/100 g and 53.09 mg/mL, respectively. In the phenolic component analysis performed with HPLC-PDA, p-OH-benzoic acid, p-coumaric acid, chrysin and pinocembrin were detected as common polyphenols in the samples. Conclusively, despite considerable variability in their monofloral characteristics, no significant differences were observed in the physicochemical and antioxidant properties of lavender honeys.Öğe A Study on Recognizing the Value of Chestnut (Castanea sativa) Blossom Waste(Ankara Univ, Fac Agriculture, 2024) Sahin, Huseyin; Kolayli, Sevgi; Kara, Yakup; Can, Zehra; Guler, Halil Ibrahim; Ozkok, Asli; Serdar, UmitChestnut (Castanea sativa) blossoms are natural resources that are not put to economic use. They are completely mixed with soil as waste. Thus, this extensive study was designed and remarkable results were found showing the potential usefulness of chestnut blossoms. In addition to the phenolic capacity and antioxidant capacity of the aqueous and ethanolic extracts of dried chestnut flowers, the anti-urease activity of these extracts was studied to demonstrate their therapeutic value. The binding interaction of phenolic substances present in chestnut blossom with urease was shown using molecular docking research. The aqueous extract, with most effect, had total phenolic content of 46.67 +/- 0.37 mg GAE/g and total flavonoid content of 6.14 +/- 0.40 mg QUE/g. The antioxidant activity was determined by FRAP (648.47 +/- 5.27 mu mol FeSO4.7H2O/g for aqueous extract and 347.53 +/- 2.09 mu mol FeSO4.7H2O/g for ethanolic extract) and DPPH (0.05 +/- 0.01 mg/mL for SC50 of aqueous extract and 0.11 +/- 0.01 mg/mL for SC50 of ethanolic extract) assays, and rutin was found to be the dominant phenolic compound according to HPLC. IC50 values for urease in aqueous and ethanolic extracts were 2.55 +/- 0.09 mg/mL and 4.57 +/- 0.24 mg/mL, respectively. According to the docking experiments, which were important to support the hypothesis of anti-urease activity, myricetin and luteolin showed different and effective bonding degrees to the target protein when compared with the reference molecule acetohydroxamic acid. In summary, chestnut flowers are rich in phenolic compounds which are responsible for a wide range of biological activities including antioxidant features and urease inhibition. These blossoms could be evaluated as potentially important raw materials for food.
