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Öğe Comparison of antidiabetic and antioxidant activities of sweet and bitter apricot kernels(Mattioli 1885, 2021) Kaya, Gulsen; Keskin, MerveFruits and their kernels have important phytochemical components for human health and nutrition. The fruits and their kernels have antioxidant effects by their seconder metabolites. Apricot (Prunus armeniaca L.) is an important fruit because of its functional properties with both its fruits and kernels. Therefore, in this study, total phenolic, flavonoid content, ferric reducing antioxidant power (FRAP) and inhibition properties of a-amylase enzyme of fruit, sweet and bitter apricot kernels were investigated. Methanol extract of each part of this fruit was prepared respectively. Total phenolic content as 241.83 +/- 1.47; 118.15 +/- 2.03 and 60.41 +/- 0.97 mg GAE/100 g, flavonoid content as 177.05 +/- 1.68; 20.08 +/- 0.63 and 32.16 +/- 0.51 mg QE / 100 g; antioxidant capacity as 0.81 +/- 0.02; 0.66 +/- 0.01 and 0.27 +/- 0.02 mM Fe2+/ mL extract were determined respectively. IC50 values for alpha amylase inhibition were calculated as 1.30 +/- 0.02; 0.74 +/- 0.01 and 3.17 +/- 0.01 mg/mL for fruit, sweet and bitter kernel extract respectively. The extracts showed good amylase inhibition properties. It can be concluded that apricot fruit and kernels might be used as a food supplement in Diabetes mellitus.Öğe DOĞAL VE FERMENTE POLENİN BİYOKİMYASAL KARAKTERİZASYONU(2021) Karlıdağ, Semiramis; Akyol, Abuzer; Keskin, Merve; Keskin, Şaban; Özkök, Aslı; Karabulut, Ercan; Yılmaz, İsmetTaze arı poleni ve arı ekmeği (Perga), zengin besin içeriği nedeniyle iki önemli arı ürünüdür. Arı ekmeği, nektar ve arı salgılarıyla karıştırılan ve petek gözlerine depolanan taze polenin bir formudur. Yani arı ekmeği, doğal fermente edilmiş bir kovan ürünüdür. Tuzaklar yardımıyla çok yüksek miktarlarda taze polen toplanabilir, ancak arı ekmeği taze arı poleni kadar üretilemez. Bu nedenle arı ekmeğinin apiterapide kullanımı sınırlıdır. Bu çalışmada, probiyotik özellikleri olduğu bilinen ticari mikroorganizmalar kullanılarak üretilen arı poleni örnekleri laboratuvarda fermente edilmiştir. Taze ve fermente edilmiş arı poleninin biyokimyasal özellikleri karşılaştırılmıştır. Taze ve fermente edilmiş arı poleni için, sırasıyla; toplam fenolik içeriği 4.43±0.03 mg GAE/g ve 6.12±0.07 mg GAE/g, demir indirgeme kapasitesi 64.14±0.18 ve 72.03±0.15 µmol FeSO4.7H2O/g numune, DPPH radikal süpürme aktivitesi 9.30±0.03 ve 6.47±0.04 mg/mL, toplam protein miktarı %21.16±0.2 ve %18.70±0.3 olarak bulundu. Elde edilen verilerden fermente arı poleninin, polene göre daha yüksek toplam fenolik içeriğe ve antioksidan kapasiteye sahip olduğu görülmektedir. Bulgulara göre taze arı poleni probiyotikler kullanılarak optimum koşullarda fermente edilebilmekte ve doğal arı ekmeğine alternatif olma potansiyeline sahiptir.Öğe GREEN SYNTHESIS AND BIOCHEMICAL PROPERTIES OF PROPOLIS BASED SILVER NANOPARTICLES(2022) Keskin, Merve; Kaya, Gülşen; Keskin, ŞabanPropolis is a substance collected by honey bees from different parts of plants. Honey bees store it in their hives in order to defend against different threats. Propolis is a bee-product rich in plant waxes, esters, fatty acids, volatile components and phenolic compounds. It`s rich phenolic content makes propolis a potential reducer for Ag+ to Ag. In this study, propolis-based silver nanoparticles were obtained using the green synthesis technique. It was determined that the obtained silver nanoparticles had a maximum absorbance at 425 nm and their sizes ranged from 67 to 75 nm. When the FT-IR data of propolis extract is examined, the band at 3200 cm-1 represents functional -OH groups, the band at 2919-2850 cm-1 represents C-H stretching, the band at 1634 cm-1 represents C=C, C=O or NH stretching, the band at 1508 cm-1 represents aromatic C=C stretching and the band at 1451 cm-1 originate from the C-H stretching of CH3, CH2, flavonoids and aromatic rings. Total phenolic content of propolis extract and silver nanoparticles was determined as 176.42±0.18 and 122.63±0.23 mg GAE/mL, respectively. IC50 value of P-AgNPs for ?-amylase and ?-glycosidase enzyme inhibition was defined as 47.08 ± 0.002 and 52.18 ± 0.001 µg/mL, respectively. Inhibition of ?-Amylase and ?-glycosidase is still a valid approach in the treatment of diabetes. The high inhibition effect of the obtained nanoparticles on the related enzymes shows that they have diabetes treatment potential. In addition, showing that cheap and abundant nanoparticles can be obtained by using propolis, this study may contribute to the development of new products containing nanoparticles that can be used in apitherapy applications.Öğe Green Synthesis, Characterization, Antioxidant, Antibacterial and Enzyme Inhibition Effects of Chestnut (Castanea sativa) Honey-Mediated Silver Nanoparticles(Mdpi, 2023) Keskin, Merve; Kaya, Gulsen; Bayram, Sinan; Kurek-Gorecka, Anna; Olczyk, PawelIn this study, chestnut honey-based silver nanoparticles (CH-AgNPs) were synthesized at different temperatures (30, 60 and 90 degrees C) and these nanoparticles were characterized by different techniques such as UV-vis spectrophotometer, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX). The DPPH free radical scavenging assay was used to determine the antioxidant activity of the obtained nanoparticles. The inhibition effects of these nanoparticles for some clinically important enzymes such as myeloperoxidase and collagenase were investigated. In addition, the disk diffusion method (DDM), agar well diffusion (AWD), and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) techniques were used to determine the antibacterial activity of CH-AgNPs. In honey-based silver nanoparticle production processes using green synthesis, it was determined that the nanoparticle sizes decreased from 55 to 27 nm with an increase in temperature. In addition, it was determined that the rate of inhibition of myeloperoxidase (36.4% to 34.0%) and collagenase enzymes (74.2% to 68.7%) increased with a decrease in particle size. As a result of the antibacterial activity tests, it was observed that CH-AgNPs have antibacterial activity against all target pathogens including Gram-positive and Gram-negative bacteria. The obtained results show that CH-AgNPs produced using chestnut honey have the potential to be used in fields such as medicine, pharmacy and cosmetic technology.Öğe Gundelia Tournefortii L. (Kenger): Determination of in vitro Antidiabetic Activities(Mattioli 1885, 2021) Keskin, Merve; Kaya, Gulsen; Keskin, SabanDiabetes mellitus is a chronic disease that negatively effects daily life. Synthetic drugs, which are inhibitors of alpha-glucosidase and alpha-amylase enzymes, are used in its treatment. These drugs may have adverse reaction on organs such as the liver. Therefore, it is important to include plants that inhibit these enzymes in the diet in the treatment of Diabetes mellitus. Gundelia tournefortii L. (Kenger) is an edible wild natural plant that is widely used as traditional food. In this study, biochemical characterization of the Gundelia tournefortii L. (Kenger) extracts was performed. The inhibition effect of the extract on alpha-amylase and alpha-glycosidase enzymes was also investigated. Total phenolic content, antioxidant activity and chemical composition of Gundelia tourneforti L. extracts were determined. Chemical composition of extracts was determined by using GC/MS technique. IC50 values of alpha-amylase and alpha-glucosidase enzymes of the Gundelia tournefortii L. ethanolic extracts of stalk were determined as 4.18 +/- 0.08 mg/mL and 9.77 +/- 1.2 mg/mL, respectively. The results showed that Gundelia tournefortii L. could be used as a supplementary food in the treatment of Type 2 diabetes.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 PROPOLİS VE PERGANIN ANTİMİKROBİYAL ETKİLERİNİN İN-VİTRO OLARAK ARAŞTIRILMASI(2021) Doğru, Feyzi; Parlakpınar, Hakan; Duman, Yücel; Özhan, Onural; Keskin, Merve; Polat, AlaadinPropolis, arıların bitkilerin çeşitli kısımlarından topladığı reçine benzeri doğal bir maddedir. Arılar propolisi çeşitli patojenlere karşı koruyucu olarak kullanırlar. Propolis zengin içeriği sayesinde birçok biyolojik etkiye sahiptir. Perga, arıların yavrularını beslemek için kullandığı polen ve baldan oluşan fermente bir üründür. Bu çalışmanın amacı fenolik bileşiklerce zengin olan perganın, antimikrobiyal aktivitesinin propolisle karşılaştırılmasıdır. Propolis ve perganın etanolik ekstraktları hazırlandı ve Folin-Ciocalteu yöntemi ile toplam fenolik bileşik miktar tayini yapıldı. Ekstraktların gram-negatif patojenler olan Escherichia coli ve Pseudomonas aeruginosa, grampozitif bir patojen olan Staphylococcus aureus ve bir mantar türü olan Candida albicans üzerinde minimum inhibitör konsantrasyon (MİK) değerleri mikrodilüsyon yöntemi ile ölçüldü. Propolis ve perga için MİK test aralığı fenolik bileşik miktarına göre 0,06µg/mL-125µg/mL olarak belirlendi. Propolis, Escherichia coli ve Pseudomonas aeruginosa’ya göre Candida albicans ve Staphylococcus aureus’a karşı düşük konsantrasyonlarda inhibe edici etki göstermiştir. Perganın Escherichia coli, Pseudomonas aeruginosa ve Candida albicans’a karşı yine düşük konsantrasyonda inhibitör etki gösterdiği; ancak, perganın Staphylococcus aureus’a karşı inhibitör etkinlik gösterebilmesi için çok daha yüksek konsantrasyonlara ihtiyaç olduğu saptanmıştır. Sonuç olarak propolis ve perganın çalışmamızda antimikrobiyal etki gösterdiği izlenmiştir.
