https://hdl.handle.net/20.500.12809/197 2026-04-20T08:24:06Z 2026-04-20T08:24:06Z Reis, İsmail Ateş, Celal Jawad, Laith https://hdl.handle.net/20.500.12809/10839 2023-08-03T13:14:55Z 2023-01-01T00:00:00Z

The asymmetry in the sagitta of four mugilid species obtained from Köyceğiz Lagoon, Aegean Sea, Turkey Reis, İsmail; Ateş, Celal; Jawad, Laith Otolith features such as size and weight were analysed in 656 fish specimens of Chelon auratus, Chelon labrosus, Chelon saliens and Mugil cephalus collected from the Köyceğiz Lagoon System, Aegean Sea, southwest Turkey. The aim was to calculate the asymmetry value of the otolith length (OL), otolith width (OW) and otolith weight (OWe). The asymmetry value of OL was greater than that of OW and OWe. The asymmetry value of the three otolith parameters increased with an increase in the fish's length. The probable cause of asymmetry in the otolith parameters investigated has been determined relative to the variability in growth prompted by ecological impact linked with the disparity in water temperature, salinity, depth and contaminants existing in the Köyceğiz Lagoon System.

2023-01-01T00:00:00Z Cerim, HasanCerim, Hasan Yılmaz, Ersin Doğu, Eralp https://hdl.handle.net/20.500.12809/10679 2023-05-22T08:39:49Z 2023-01-01T00:00:00Z

Effects of Lunar Phases and Weather Conditions on Small-scale and Trawl Fishery Landings in Southern Aegean Sea, Turkiye Cerim, HasanCerim, Hasan; Yılmaz, Ersin; Doğu, Eralp Several studies have investigated the effect of the lunar phase and weather conditions on animal behaviour. As in other parts of the world, fishermen may modify their behaviour in response to the weather conditions and the moon cycle in Turkey. The main objective of the study was to find out the answer to "Do lunar illumination and weather conditions have effects on trawl and small-scale fishery landings in the southern Aegean Sea?". The study results showed that while cloudiness has a positive effect, lunar illumination, lunar distance and mean wind speed have negative impacts on small-scale fishery landings. On the other hand, the trawl fishery is affected positively by cloudiness. However, lunar illumination has a negative impact on trawl landings. Apart from the effects of the lunar cycle and weather on fisheries landings, other factors such as oceanographic variables, anthropogenic impact and climate change should also be investigated.

2023-01-01T00:00:00Z Baygar, Tuba Saraç, Nurdan Ceylan, Özgür Balcı, Uydu Uğur, Aysel Boran, Rukiye https://hdl.handle.net/20.500.12809/10425 2022-12-05T11:22:36Z 2022-01-01T00:00:00Z

In vitro biological activities of potassium metaborate; antioxidative, antimicrobial and antibiofilm properties Baygar, Tuba; Saraç, Nurdan; Ceylan, Özgür; Balcı, Uydu; Uğur, Aysel; Boran, Rukiye Antioxidant, antimicrobial and antibiofilm activities of potassium metaborate (KBO2) was investigated within the present study. Antioxidant capacity of potassium metaborate was determined by β-carotene bleaching (BCB) assay and hydroxyl radical scavenging activity. Potassium metaborate was evaluated for its antimicrobial effects against selected Gram-positive bacteria, Gram-negative bacteria and a yeast via broth dilution method. The inhibition capability of potassium metaborate on the microbial biofilm formation of tested microorganisms was measured by microplate biofilm method using MTT (3- [4, 5- dimethyl-2-thiazolyl]-2, 5-diphenyl-2H-tetrazolium-bromide). Biofilm inhibition capacity of potassium metaborate was also observed by Scanning Electron Microscope (SEM). Potassium metaborate was found to have the ability to scavenge hydroxyl radicals with an inhibition rate of 71.13% at 100 mM concentration. Antioxidant activity of potassium metaborate as determined by BCB assay gave higher result with an inhibition rate of 86.96% at the same concentration. According to the MIC (minimum inhibition concentration) values, the potassium metaborate inhibited the growth of C. albicans, S. aureus and E. coli at 62.5 mM concentrations while it was 31.25 mM for B. subtilis and 125 mM for P. aeruginosa. The highest antibiofilm activity was determined at the MIC of potassium metaborate with the reduction rate of 90.18% against C. albicans. It was concluded that, potassium metaborate have strong biological activities and can be effectively used for biomedical and environmental solutions.

2022-01-01T00:00:00Z Metin, Cansu Alpaslan, Yunus Ekşi, Zerrin Baygar, Taçnur https://hdl.handle.net/20.500.12809/10313 2022-10-04T07:58:21Z 2022-01-01T00:00:00Z

Effects of different thawing methods on fatty acid composition of cultured sea bass (Dicentrarchus labrax Linnaeus, 1758) Metin, Cansu; Alpaslan, Yunus; Ekşi, Zerrin; Baygar, Taçnur This study aimed to determine the potential changes in the fatty acid composition of frozen cultured sea bass (Dicentrarchus labrax) thawed at different environmental conditions. Sea bass fillets were thawed using four different methodologies: refrigerator (+4°C), water (+15°C), microwave (defrost mode) and ambient conditions (22±2°C). Some part of the fish was thawed once (on the 7th and 30th days), and the other part was thawed twice (on the 30th day). Thus, crude lipid analysis and fatty acid composition by gas chromatography were carried out in the thawed sea bass fillets. The results showed negative effects on the fatty acid composition caused by the different thawing methods. The most suitable thawing method was determined as refrigerator thawing, especially on the 30th day 1st thawing according to least loss of the lipid values (9.19±0.18%) and unsaturated fatty acids (C18:2 25.92±0.13%, C20:5 5.56±0.02%, C22:6n-3 8.90±0.09%, ∑PUFA 44.70±0.04%). Samples thawed in water and ambient conditions follow the refrigerator thawing method in terms of lipid and fatty acids. The highest lipid and fatty acid loss was observed in microwave thawing. Although the samples thawed in the refrigerator were better than the other groups in terms of lipid content and fatty acid composition, it is recommended to the consumers that frozen foods should be thawed only once and consumed immediately, and that fish should be frozen according to their needs and thaw as much as they can consume.; Bu çalışmada, dondurma ve farklı ortam şartlarında çözündürme işlemi uygulanan kültür levrek balığının (Dicentrarchus labrax Linnaeus, 1758) yağ asidi kompozisyonunda meydana gelen değişimlerin tespiti amaçlanmıştır. Levrek balığı filetoları, buzdolabı (+4°C), su (+15°C), mikrodalga (buz çözme modu) ve ortam şartları (22±2°C)’nda olmak üzere dört farklı ortamda çözündürülmüştür. Balıkların bir kısmı bir (7. ve 30. günde), diğer kısmı ise iki kez (30. günde) çözündürülmüştür. Çözündürülen levrek balığı filetolarında ham yağ ve yağ asitleri kompozisyonu analizleri gerçekleştirilmiştir. Tüm grupların yağ asidi kompozisyonu gaz kromatografi cihazı kullanılarak belirlenmiştir. Elde edilen bulgular farklı ortamlarda birden fazla çözündürmenin yağ asitleri kompozisyonu üzerinde olumsuz etkilere sebep olduğunu ortaya koymuştur. Uygulanan çözündürme tekniklerinden en uygun çözündürme ortamının özellikle 30. gün ilk çözündürme günü ele alındığında yağ değerleri (%9,19±0,18) ve doymamış yağ asitleri sonuçlarında (C18:2 %25,92±0,13, C20:5 %5,56±0,02, C22:6n-3 %8,90±0,09, ∑PUFA %44,70±0,04) en az kayıp görülmesinden dolayı buzdolabında çözündürme yöntemi olduğu sonucuna varılmıştır. Suda ve ortam koşullarında çözündürülen örnekler yağ ve yağ asitleri sonuçları bakımından buzdolabında çözündürme yöntemini takip etmektedir. Yağ ve yağ asidi miktarında en fazla kayıp mikrodalga çözündürme yönteminde gözlenmiştir. Buzdolabında çözündürülen örnekler her ne kadar yağ miktarı ve yağ asitleri kompozisyonu açısından diğer gruplara göre daha iyi olsalar bile tüketicilere dondurulmuş gıdaların sadece bir kere çözündürülerek hemen tüketilmeleri gerektiği ve ihtiyaçları oranında balıkları dondurup, yiyebilecekleri kadar miktarları çözündürmeleri önerilmektedir.

2022-01-01T00:00:00Z