During conventional fermentation of milk into yogurt and kefir, changes of antioxidant capacities (DPPH radical scavenging, ferrous chelating, reducing power, hydrogen peroxide/ H2O2 scavenging activity) and total phenolic content were investigated. Both products showed greater phenolic content, DPPH radical scavenging, and reducing power activities than was the case of their unfermented milk forms. But they were unable to scavenge H2O2. Chelating ability of milk increased by yogurt fermentation but decreased by kefir fermentation. In general, antioxidative capacity of milk improved throughout conventional yogurt and kefir fermentations and ripening periods (except chelating ability for kefir and H2O2 scavenging). This study is valuable since it evaluates the antioxidant power of yogurt and kefir produced by traditional fermentation with 5 different antioxidative approaches. In face of rapidly rising consumer demand for safe, healthy, functional but natural foods, revealed results might strengthen importance of conventional fermentation process and highlight the antioxidative contributions of mentioned products

In the study, the bioactive, physicochemical and antimicrobial properties of koruk juice and dried koruk pomace were investigated. The total phenolic contents of koruk juice and pomace were determined as 1119.670 and 1182.170 mg GAE/L, respectively. Higher DPPH radical scavenging activity found in koruk pomace, which was consistent with total phenolic contents. Organic acid, total sugar and ascorbic acid contents of koruk juice (3.44%, 4.737 g/L and 2.559 mg/100 mL) were higher than koruk pomace (0.19%, 0.866 g/L and 0.242 mg/100 mL). The counts of Total Psychrophilic Aerobic Bacteria and mold-yeast in pomace were determined as 0.694 and 1.016 log CFU/g, respectively, while no growth was observed in koruk juice. Koruk juice and pomace indicated antimicrobial effect on all test microorganisms in the range of 31.3-500.0 µg/mL (Minimum Inhibition Concentration). The most sensitive bacteria to koruk juice were Bacillus cereus, while Pediococcus acidilactici was the most sensitive one to koruk pomace. Koruk juice also showed bactericidal effect on all test cultures at concentration ranging between 250.0 and 500.0 µg/mL (Minimum Bactericidal Concentration), koruk pomace was not showed bactericidal effect on Escherichia coli O157:H7, Salmonella Typhimurium, E. coli and B. cereus. This study demonstrated that the koruk products could be used in food applications as natural antioxidant and antimicrobial substance.

This study was carried out between 2017 and 2018 to determine physical and chemical influences of two drying methods (drying on wooden fruit drying trays and drying cloths), two harvesting periods (commercial / physiological maturity and late harvest), and two harvesting methods (harvesting by hand and shaking) on dried fruit samples of Hacıhaliloğlu and Kabaaşı cultivars. Titrable acidity, browning level, total phenolic content, antioxidant activity (ABTS), color (L*, a*, b*), pH, humidity and water activity (aw) parameters of dried fruit samples were examined. Results indicated that different harvesting periods, methods and drying methods significantly affected almost all fruit quality parameters. L value was higher in apricots dried on trays than dried on the cloths. L* values of dried apricots ranged from 27,13 to 54,74. Similarly, moisture content and water activity values were also found to be lower in apricots dried on wooden fruit drying trays than dried on clothes. When chemical parameters were examined, it was observed that phenolic compounds and total antioxidant contents decreased with fruit ripening. The effect of the applications on drying efficiency was not determined as significant, on the contrary, the individual weights of the dried apricots harvested at the late period were found significantly higher and the number of dried apricots per kilogram was lower. As a result of the study, it was concluded that in sun-dried apricot production, harvesting at late period and the drying on trays positively affected various quality parameters.

The shrublands are very common in Urla-Çeşme-Karaburun peninsula located in the western point of Turkey. Prickly shrubby burnet (Sarcopoterium spinosum L.) is one of the common weed which has intensive thorns making its consumption for the local domestic animals. However, Sarcopoterium spinosum is a valuable and common medicinal plant in the Mediterranean region. Crude extract of S. spinosum leaves exhibited higher antioxidant activity, as 3143.5± 238.5 µM TEAC (Trolox Equivalent Antioxidant Capacity)/g dry weight (DW), when compared to other medicinal plants found in the literature. The aim of this study was to determine the effect of extraction parameters on the content and biological activity of the extract by response surface methodology (RSM) as well as to identify its major compounds. High Performance Liquid Chromatography (HPLC) was employed to investigate the phenolic content of S. spinosum extract. The composition of the phenolic contents including hyperoside and isoquercetin, the latter being the major component, in S. spinosum extract has been shown for the first time by HPLC. Antimicrobial activity of S. spinosum extract, identified by minimum inhibition concentration (MIC) assay, indicated that the crude extract had antifungal activity against Candida albicans.

Wheat, one of the world's most important agricultural products, plays a vital role in meeting the nutritional needs of our growing global population. However, arid and semi-arid regions face a potential threat from boron (B) toxicity. While boron is an essential nutrient for plant growth and development, its excessive presence can be toxic. It disrupts physiological processes, causing chlorosis and necrosis, ultimately leading to yield loss or plant death. Although B deficiency is a problem in the soils of many countries, Türkiye is one of the few experiencing B toxicity problems in its agricultural areas. This study investigated the physiological and biochemical responses of durum wheat to various B concentrations (0-20 mg L-1) under controlled air-conditioned cabin conditions. Durum wheat exhibited a decrease in chlorophyll content, phenolic content, and antiradical capacity at B doses exceeding 10 mg L-1. However, carotene content increased steadily with increasing B concentrations. The activities of antioxidant enzymes, including superoxide dismutase (SOD), ascorbate peroxidase (APX), and glutathione S-transferase (GST), increased up to a B dose of 15 mg L-1. Catalase (CAT) and glutathione reductase (GR) activities increased up to 10 mg L-1 B dose but decreased at higher B levels. Proline content increased tenfold up to a B dose of 10 mg L-1, indicating an attempt to mitigate stress. Conversely, malondialdehyde (MDA) accumulation increased continuously (approximately 150%) with increasing B doses, suggesting membrane damage. Despite being considered B-sensitive, this study demonstrated that durum wheat can effectively cope with B stress up to a B dose of 10 mg L-1 under controlled conditions. Beyond this threshold, physiological and biochemical changes indicate a decline in stress tolerance. Many osmoregulators, carotenes, alkaloids, flavonoids, tocopherols, phenolic compounds, non-protein amino acids, and several unidentified metabolites are activated to support antioxidant defense. The SOS pathway and the released ROS force gene regulatory systems come into play. Following these, the ROS released in the organism are neutralized, and ionic homeostasis and cellular stress resistance are achieved.