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Öğe Antioxidant capacity and chemical properties of selected barberry (Berberis vulgaris L.) fruits(KOREAN SOC HORTICULTURAL SCIENCE, 2012) Ozgen, Mustafa; Saracoglu, Onur; Gecer, Esma NurSix purple-black barberry accessions (Berberis vulgaris L.) were obtained from various sites in Sivas province of Turkey. Fruits were analyzed for their total phenolic (TP), total monomeric anthocyanin (TMA) contents and for their antioxidant capacity by the ferric reducing antioxidant power (FRAP) and TEAC assays. Sugar and organic acid composition were also determined by HPLC. TP and TMA contents were measured using the Folin-Ciocalteu reagent and pH differential methods, respectively. Variability between the accessions was not high. Variability among accessions was greatest for FRAP content (C.V. 17.9%); individuals ranged from 41.0 to 65.6 mu mol TE center dot g(-1) on a fresh weight basis. Variation among the accessions was also evident for TP, TMA, and TEAC values (C.V. 16.21%, 14.85%, and 7.13%, respectively). The major sugars of barberry fruits were glucose (8.84 g center dot 100 mL(-1)) and fructose (6.12 g center dot 100 mL(-1)) and dominant organic acids were malic (7.59 g center dot 100 mL(-1)) and citric (1.34 g center dot 100 mL(-1)). Within this limited study of six different accessions, chemical profile and antioxidant capacity of barberry fruits have rich source of natural antioxidant substances.Öğe Antioxidant potential of Turkish pepper (Capsicum annuum L.) genotypes at two different maturity stages(TUBITAK SCIENTIFIC & TECHNICAL RESEARCH COUNCIL TURKEY, 2016) Keles, Davut; Ozgen, Senay; Saracoglu, Onur; Ata, Atilla; Ozgen, MustafaImproved phytochemicals and antioxidant properties in crops are becoming important traits in many breeding programs. In this study, along with several other horticultural attributes, total phenolic content (TP) and antioxidant capacity (ferric reducing ability of plasma (FRAP) and Trolox equivalent antioxidant capacity (TEAC)) of 52 superior pepper genotypes from the Alata Pepper Breeding Program were examined. The fruits from these plants were harvested at immature and mature stages. The genotypes greatly varied for TP, FRAP, TEAC, soluble solids, vitamin C content, and fruit color as determined by L, a and b values. The range for TP was 319-4047 mu g GAE/g fresh weight (fw), while FRAP and TEAC varied between 0.22 and 0.56 mu mol of TE/g fw and 0.08 and 1.88 mu mol TE/g fw. All these characteristics were considerably variable between immature and mature stages. These characteristics were also found to be significantly correlated. Principal component analyses conducted for all the characters used in the study and constructed separately for immature and mature stages demonstrated no obvious patterns for pepper types. Therefore, our overall results suggest that individual pepper cultivars having high total phenolic and antioxidant capacity can be utilized in developing new pepper cultivars with rich phytochemical content.Öğe Chitosan nanoparticles enhances the anti-quorum sensing activity of kaempferol(Elsevier Science Bv, 2017) Ilk, Sedef; Saglam, Necdet; Ozgen, Mustafa; Korkusuz, FezaQuorum sensing (QS) is a cell density dependent expression of species in bacteria mediated by compounds called autoinducers (AI). Several processes responsible for successful establishment of bacterial infection are mediated by QS. Inhibition of QS is therefore being considered as a new target for antimicrobial chemotherapy. Flavonoid compounds are strong antioxidant and antimicrobial agents but their applications are limited due to their poor dissolution and bioavailability. Our objective was to investigate the effect of kaempferol loaded chitosan nanoparticles on modulating QS mediated by AI in model bioassay test systems. For this purpose, kaempferol loaded nanoparticles were synthesized and characterized in terms of hydrodynamic diameter, hydrogen bonding, amorphous transformation and antioxidant activity. QS inhibition in time dependent manner of nanoparticles was measured in violacein pigment producing using the biosensor strain Chromobacterium violaceum CV026 mediated by AI known as acylated homoserine lactone (AHL). Our results indicated that the average kaempferol loaded chitosan/TPP nanoparticle size and zeta potential were 192.27 +/- 13.6 nm and +35 mV, respectively. The loading and encapsulation efficiency of kaempferol into chitosan/TPP nanoparticles presented higher values between 78 and 93%. Kaempferol loaded chitosan/TPP nanoparticle during the 30 storage days significantly inhibited the production of violacein pigment in Chromobacterium violaceum CV026. The observation that kaempferol encapsulated chitosan nanoparticles can inhibit QS related processes opens up an exciting new strategy for antimicrobial chemotherapy as stable QS-based anti-biofilm agents. (C) 2016 Elsevier B.V. All rights reserved.Öğe INVESTIGATION OF USE IN WASTEWATER TREATMENT OF NANOFIBERS OBTAINED FROM OSAGE ORANGE FRUIT(STEF92 TECHNOLOGY LTD, 2016) Ilk, Sedef; Battaloglu, Rifat; Yalcin, M. Gurhan; Ozgen, MustafaThe aim of this study was to prepare electrospun chitosan-based nanofiber mats and to incorporate the fruit extracts of Osage Orange (Madura Pomifera) into the mats. Chitosan-ethylenediaminetetraacetic acid/polyvinyl alcohol (CS-EDTA/PVA) was selected as the polymers. The osage orange extracts with 3 wt% were incorporated into the CS-EDTA/PVA solution and electrospun to obtain nanofibers. The morphology and diameters of the mats were analyzed using scanning electron microscopy (SEM). The chemical bonding properties were investigated by fourier transform infrared spectroscopy (FT-IR). Finally, the sorption potential of Osage Orange loaded nanofibers for the removal of common metallic pollutants, cadmium (Cd2+), cobalt (Co2+), copper (Cu2+), nickel (Ni2+) and lead (Pb2+) was also investigated. The results indicated that the diameters of the fibers were on the nanoscale and that no crystals of the extract were observed in the mats. Osage Orange loaded chitosan based nanofiber adsorbent presented good absorption capacity for all tested metals ranged between 29-34%. In conclusion, our experiments demonstrated that biomaterials composed of osage orange loaded CS EDTA nanofibers have a potential adsorbent for heavy metal.Öğe Kaempferol loaded lecithin/chitosan nanoparticles: preparation, characterization, and their potential applications as a sustainable antifungal agent(TAYLOR & FRANCIS LTD, 2017) Ilk, Sedef; Saglam, Necdet; Ozgen, MustafaFlavonoid compounds are strong antioxidant and antifungal agents but their applications are limited due to their poor dissolution and bioavailability. The use of nanotechnology in agriculture has received increasing attention, with the development of new formulations containing active compounds. In this study, kaempferol (KAE) was loaded into lecithin/chitosan nanoparticles (LC NPs) to determine antifungal activity compared to pure KAE against the phytopathogenic fungus Fusarium oxysporium to resolve the bioavailability problem. The influence of formulation parameters on the physicochemical properties of KAE loaded lecithin chitosan nanoparticles (KAE-LC NPs) were studied by using the electrostatic self-assembly technique. KAE-LC NPs were characterized in terms of physicochemical properties. KAE has been successfully encapsulated in LC NPs with an efficiency of 93.8 +/- 4.28% and KAE-LC NPs showed good physicochemical stability. Moreover, in vitro evaluation of the KAE-LC NP system was made by the release kinetics, antioxidant and antifungal activity in a time-dependent manner against free KAE. Encapsulated KAE exhibited a significantly inhibition efficacy (67%) against Fusarium oxysporium at the end of the 60 day storage period. The results indicated that KAE-LC NP formulation could solve the problems related to the solubility and loss of KAE during use and storage. The new nanoparticle system enables the use of smaller quantities of fungicide and therefore, offers a more environmentally friendly method of controlling fungal pathogens in agriculture.Öğe LESS KNOWN VACCINIUM: ANTIOXIDANT AND CHEMICAL PROPERTIES OF SELECTED CAUCASIAN WHORTLEBERRY (Vaccinium arctostaphylos) FRUITS NATIVE TO BLACK SEA REGION OF TURKEY(WYDAWNICTWO AKAD ROLNICZEJ W LUBLINIE, 2014) Ozgen, Mustafa; Celik, Huseyin; Saracoglu, OnurThere is an increasing interest in the commericalization of native fruits for food and medicinal extract utilization. This study was undertaken to determine the antioxidant and chemical properties of selected caucasian whortleberry from the native region of Northeastern Turkey. Caucasian whortleberry (Vaccinium arctostaphylos L.), a close relative to cultivated blueberries, were harvested from various sites of Black sea region of Turkey and were analyzed for their total phenolic (TP), anthocyanin (TA) contents, and their antioxidant capacity by FRAP and TEAC assays. Specific sugar and organic acid composition were also determined by the help of HPLC. ARC-1, and ARC-6 displayed the highest TP contents (5780 and 5754 mu g GAB g(-1) fw). The TA values were spectrophotometrically estimated and they were varied between 74.7 (ARC-6) and 194.4 (ARC-4) mu g del-3-glu g(-1) fresh weight basis. ARC-1 had the highest amount (19.5 and 23.4 mu mol TE g(-1) fw) of antioxidant capacity or both TEAC and FRAP assays. Fructose and glucose were found to be predominant sugars in all genotypes analyzed. The concentrations of fructose and glucose were averaged at 45.1 and 41.2 g kg(-1) fw respectively. The organic acid distribution of berries was dominated by citric acid (mean of 9.85 g kg(-1) fw). These results may provide evidence that Caucasian whortleberry has strong antioxidant capacity. Also, results of this study may be used for utilization of selected genotypes in the breeding studies of close relative vaccinium plants.Öğe Lysophosphatidylethanolamine (LPE) Improves Fruit Size, Color, Quality and Phytochemical Contents of Sweet Cherry c.v. '0900 Ziraat'(KOREAN SOC HORTICULTURAL SCIENCE, 2015) Ozgen, Mustafa; Serce, Sedat; Akca, Yasar; Hong, Ji HeunLysophosphatidylethanolamine (LPE) affects the quality of flowers, fruits, and other horticultural products. Studies have provided evidence that LPE can accelerate ripening of fruits and prolong shelf-life at the same time. In this study, the influence of LPE on anthocyanin accumulation and phytochemical characteristics of sweet cherry was investigated. LPE (10 mg center dot L-1) was applied to a commercial sweet cherry c.v. '0900 Ziraat' orchard two and four weeks before harvest for two treatment years (2011 and 2012). Preharvest applications of LPE resulted in significant improvement in both pomological and phytochemical attributes at harvest. LPE treatment led to a 17% increase in fruit weight and a 6% increase in soluble solid content when averaged over two experimental years. Fruit phytochemical content and antioxidant capacity were increased significantly. The average total phenolic content of LPE-treated fruits for the two years was 703 mu g gallic acid equivalent (GAE)/g fresh weight (g FW) compared to 569 mu g GAE/g FW in the untreated control. Fruits treated with LPE had a 27% and 16% more anthocyanin than the control fruits in 2011 and 2012. Antioxidant capacity of fruits, as measured by TEAC (Trolox equivalent antioxidant capacity) assay, was 12.5 and 11.4 mu mol TE/g FW in LPE-treated and untreated control fruits, respectively, when averaged over two experimental years. Our results suggest that preharvest application of LPE may have the potential to increase anthocyanin accumulation, improve fruit quality and enhance phytochemical characteristics of sweet cherries.Öğe Quality and nutritional property changes in stored dried apricots fumigated by sulfur dioxide(KOREAN SOC HORTICULTURAL SCIENCE, 2015) Sen, Fatih; Ozgen, Mustafa; Asma, Bayram Murat; Aksoy, UygunApricots are grown in many countries and are marketed as dried or fresh. Sulfur fumigation is preferred as a low-cost pre-treatment to maintain apricot color. This study aims to determine the effect of sulfur dioxide (SO2) concentration on quality and nutritional properties of dried apricot fruits during storage. Apricot fruits were treated with different concentrations of SO2 (1,250, 2,000, and 3,500 mg center dot kg(-1)) and then stored at 20A degrees C under 50-65% relative humidity conditions for 18 months. Fruit SO2 concentration decreased rapidly during the initial stage and then decreased at a slower rate. Fruit color darkening became more pronounced after 12 months, especially in the fruit treated with 1,250 and 2,000 mg center dot kg(-1) SO2. After 18 months of storage, total phenolic content (839-890 mg GAE 100 g(-1) dry weight), antioxidant activity (9.4-11.6 mu mol TE g(-1) dry weight), and beta-carotene levels (42.7-47.6 mg center dot kg(-1)) of all treatments varied only slightly, despite lower values overall. Therefore, SO2 levels must be chosen based on the expected storage conditions and length of the storage period.Öğe SYNTHESIS, CHARACTERIZATION AND ANTIMICROBIAL ACTIVITY OF CHITOSAN/CLAY NANOCOMPOSITES(STEF92 TECHNOLOGY LTD, 2016) Ilk, Sedef; Yalcin, M. Gurhan; Battaloglu, Rifat; Ozgen, MustafaClay-based bionanocomposites have gained great attention due to their nanosized functional properties and safe natural structures. Combination at the nanometric scale of the increased surface areas and reactive surfaces of clays with the functional behavior of biopolymers has been pointed out as an attractive way to develop organic-inorganic nanohybrid materials with properties that are inherent to both types of components. In this study a natural-based nanocomposite film consisting of chitosan and organic clay was synthesized. Montmorillonite modified with octadecylamine (ODA-MMT) was used as an organically modified layered silicate. The nanocomposite was prepared by mixing a acetic acid suspension of ODA-MMT with a solution containing chitosan as the macroscopic polymer matrix. The effect of ODA-MMT content (0.5-3%) on the structure and antimicrobial activity of the nanocomposite have been investigated. The interactions between the chitosan matrix and ODA-MMT at different conditions were evaluated using SEM, TEM, XRD and DSC analysis. The results indicated that the formation of exfoliated nanostructure and the thermal stability of nanocomposites was improved within increased loading of nano-dispersed clay in matrix. Antimicrobial activity of chitosan/ODA-MMT nanocomposites was evaluated using disc diffusion method against Gram-positive bacteria Staphylococcus aureus ATCC 25923 and Streptococcus mutans ATCC 25175 and Gram-negative bacteria Escherichia colt ATCC 25922 and Salmonella spp. (Laboratory stock). The antimicrobial activity studies of the nanocomposites showed that the nanocomposites could more strongly inhibit the growth of the tested Gram-positive bacteria than Gram negative bacteria. The inhibitory effect of nanocomposites on microorganisms increased with the increasing content of ODA-MMT. The results showed that the strong antimicrobial activity of the nanocomposites may be related to the interaction and the fine dispersion between chitosan and clay.
