Ascorbic acid (Vitamin C) is one of the important antioxidants, which naturally present in seminal plasma of fish. On the other hand, whether its effect may improve sperm quality following cryopreservation process still remains its uncertainty. Thus, the present study aimed to analyse the effect of different extenders supplemented with different ascorbic acid concentrations on post-thaw motility and fertility of frozen-thawed rainbow trout (Oncorhynchus mykiss) sperm. Selected sperm samples were pooled and diluted at 1:3 ratios with two different extenders (E) composing such as (E-1) 300 mM glucose, 10% egg yolk and 10% DMSO and (E-2) 0.6 mM sucrose and 10% DMSO. Each extender was supplemented with vitamin C at 1, 5 and 10 mM concentrations. Following dilution, the sperm was loaded into 0.25 ml straws and frozen in liquid nitrogen vapour. The straws were then plunged into liquid nitrogen for storage. Fertilization was carried out using the dry fertilization technique. Highest post-thaw motility (50±5.77) and fertilization (56±1.00) results were obtained with the extender-1 (E-1) containing 10% DMSO concentration. In conclusion, the present study indicated that addition of ascorbic acid to the extenders improved rainbow trout sperm motility resulting higher fertilization of the eggs.

Bu çalışmada, Osmanlı çileğinin ana ebeveyn, yerel (Karaçilek, Tüylü, Deli) ve standart (Kabarla, Sweet Ann ve Sweet Charlie) çilek çeşitlerinin tozlayıcı olarak kullanıldığı ıslah çalışması sonucu seçilen elli iki adet F1 genotipi ve ana ebeveynleri kullanılmıştır. Elde edilen meyvelerde suda çözünebilir kuru madde miktarı (%), pH, titre edilebilir asitlik (TA) (%), toplam kuru madde miktarı (%), kül tayini, askorbik asit içeriği (mg/100g) ve toplam fenol miktarı (µg GAE/g ta) belirlenmiştir. Araştırma sonuçları incelendiğinde SÇKM değerlerinin %5,80 ile %14,60; pH değerinin 2,69-3,90; titre edilebilir asit miktarının %0,58-1,79 arasında değiştiği belirlenmiştir. Askorbik asit en yüksek DB-119 genotipinde 55,61 mg/100g bulunurken, en yüksek toplam fenolik madde miktarı DC-42 genotipinde 3887,07µg GAE/g ta bulunmuştur. Meyve yapısının genetik faktörlerden etkilendiği ancak çevre koşularının etkileşimi ile meyve yapısında değişiklik olduğu bilinmektedir. Çalışma sonucunda belirlenen kriterler incelendiğinde melez bireylerin ana ebeveynlerine yakın değer aralığında olduğu belirlenmiştir.

The objective of this study was to investigate the effect of pre-treatment and drying temperature on the drying kinetics and nutritional quality of tomato (Lycopersicon esculantum L.) under hot air drying. Tomato samples were blanched at 80oC and osmotically dehydrated using 20% w/w sodium chloride solutions at 30oC for 20 min. The blanch-osmotic pre-treated and untreated tomato slices were dried at temperature of 40, 50, 60, 70 and 80oC, respectively in a hot air-dryer. The results showed that blanch-osmotic pre-treatment offered a higher drying rate and lower or faster drying time than untreated condition. The tomato drying regime was characteristically in the constant and falling rate period. The tomato drying rate curve showed characteristics of porous hygroscopic solids. The optimum drying temperature for tomato was found to be 60oC. Four semi-empirical drying models of Newton, Page, Henderson and Pabis, and Logarithmic were fitted to the drying data using non-linear regression analysis. The most appropriate model was selected using the coefficient of determination (R2) and root mean square error (RMSE). The Page model has shown a better fit to the drying kinetics data of tomato in comparison with other tested models. Transport of moisture during drying was described by Fick’s diffusion model application and the effective moisture diffusivity (Deff) thus estimated. The Deff at 60oC was 4.43 × 10-11m2/s and 6.33 × 10-11m2/s for blanch-osmotic pre-treated and untreated tomato slices, respectively.