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Öğe Bee collected pollen as a value-added product rich in bioactive compounds and unsaturated fatty acids: A comparative study from Turkey and Romania(Elsevier, 2021) Margaoan, Rodica; Ozkok, Asli; Keskin, Saban; Mayda, Nazli; Urcan, Adriana Cristina; Cornea-Cipcigan, MihaielaThe aim of this study was to determine the botanical origin, phenolics, flavonoids and fatty acids content, antioxidant and antimicrobial properties, of 18 bee collected pollen (BP) samples from Turkey and Romania. Five plant families with predominant pollens (>45%) were found in the Turkish samples, and only three in the Romanian samples. The phenolic content, varied between 16.40 and 41.17 mg GAE/g and the flavonoids content varied between 2.39 and 7.17 mg QE/g. The highest value of DPPH was 2.93 mmol Trolox/g and 9.64 mmol Trolox/g for the TEAC, whereas the IC50 value of alpha-Amylase inhibition was 8.10 mg/mL. We also verified that the presence of the methanolic extract of BP differentially affected the growth of Gram-positive and Gram-negative bacteria under study, strongly depending on the microorganism and the botanical origin of the BP samples used. The fatty acids contents were closely correlated with the above-mentioned parameters especially with the botanical origin and antibacterial activity. Our findings suggest that BP is a rich source of unsaturated fatty acids and bioactive compounds, which can be considered a value-added product. Furthermore, the differences in Turkish and Romanian BP chemical composition is also shown based on their antimicrobial and alpha-amylase inhibitory activities.Öğe Evaluation of Antimicrobial Efficacy and Phenolic Compound Profiles in Geopropolis Samples from Bolivia and Venezuela(Kafkas Univ, Veteriner Fakultesi Dergisi, 2024) Koru, Ozgur; Bedir, Orhan; Vit, Patricia; Gencay Celemli, Omur; Mayda, NazliIn this study, we investigated the balsamic contents, total phenolic contents, flavoneflavonol contents, and flavanones-dihydroflavonols contents, and antimicrobial effects of seven geopropolis samples produced by four neotropical stingless bee species: Venezuelan Melipona favosa, and Bolivian M. grandis, Scaptotrigona depilis, S. polysticta. The balsamic content value was found highest in the sample of S. polysticta (sample 7) collected from Bolivia, highest total phenolic content in M. favosa geopropolis (sample 1) from Venezuela, highest flavone-flavonol content in M. favosa geopropolis (sample 2) collected from Venezuela and highest flavones-dihydroflavonols content in S. polystica (sample 7) from Bolivia. As a result, except for balsamic content values, other investigated values were lower compare to the previous researches about different stingless bee species geopropolis. This is proved that climatic conditions, bee species and collecting area affected the chemical content of geopropolis significantly. The antimicrobial findings indicated that the examined geopropolis extracts displayed different degrees of inhibition against the growth of Gram-positive bacteria and fungi, which correlated with their phenolic contents. Nevertheless, these extracts did not demonstrate a comprehensive inhibitory effect on Gram-negative bacteria. Standardized geopropolis samples, rich in phenolic content, can complement antibiotics naturally for preventing and treating infections from Gram-positive bacteria and Candida albicans. However, further studies are still needed regarding the clinical applications of geopropolis in various infections.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 Microscopic examination and comparison of exine layer of bee pollen and bee bread (Perga)(Istanbul Univ, Fac Pharmacy, 2022) Ozkok, Ash; Bakhshpour, Monireh; Mayda, Nazli; Denizli, Adil; Sorkun, KadriyeBackground and Aims: Thanks to their high nutritional content and therapeutic effects, bee pollen and bee bread (perga) are used as a food supplement. Studies have shown that bee bread has more bioavailability than bee pollen. This situation has been explained by the fragmentation of the exine layers of pollen in bee bread in some studies. However, there is no clear microscopic study showing that the exine layer is broken. This study investigated for the first time whether the pollen grains in bee bread were fragmented in the exine layers after fermentation, in comparison with the pollen grains in bee pollen samples. Methods: Bee pollen and bee bread samples were collected from the same hives and pollen slides were prepared for examination with light and SEM microscopes. Both of the pollen slides were compared and microscopic photographs were taken. Results: No deformation was observed in the exine layers of the pollen grains in bee bread after fermentation. Conclusion: In many studies, the higher bioavailability of bee bread has been explained by the deformation at exine structure of the pollen grains. But it has not been supported microscopically in detail with both light and SEM microscopes. Our study's conclusion was that no deformation was observed in the exine structures of the pollen in bee bread after fermentation.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 Total Bioactive Compounds and Antimicrobial Capacities of Bee Pollen with Different Botanical Origins(Univ Agricultural Sciences & Veterinary Medicine Cluj-Napoca, 2021) Ozkok, Asli; Koru, Ozgur; Bedir, Orhan; Cetinkaya, Serdar; Celemli, Omur Gencay; Ozenirler, Cigdem; Mayda, NazliBee pollen has many therapeutic properties with its rich chemical content. Especially the phenolic substances in the structure of bee pollen are very effective in showing the bioactive compounds. Thanks to these properties, bee pollen is used as a food supplement. It is known that these features are influenced by many factors such as climate, geography and plant origin. Therefore, it is important to determine the botanical origins of bee products. In this study, botanical origins and total bioactive compounds were determined at the seven bee pollen samples collected from different regions of Turkey. Also, antimicrobial activity of the seven bee pollen samples against seven different bacterial pathogens and one fungal agent using broth microdilution method were studied. Asteraceae, Fabaceae, Cistaceae, Papaveraceae families were found as a dominant in the regions by botanical origins examination. Total phenolic values were found between 24.77 +/- 288.824 mg GAE/g and 51.61 +/- 727.14 mg GAE/g. Total flavonoid content was 1.36 +/- 0.015 mg QE/g and 2.40 +/- 0.077 mg QE/g. The antimicrobial results showed that each of the tested bee pollen samples inhibited the growth of the gram-positive and gramnegative bacteria at the different levels while they did not have a complete inhibitory effect on the fungi.
