scholarly journals Uskumru (Scomber scombrus) ve Levrek (Dicentrarchus labrax ) Kemiklerinden Jelatin Ekstraksiyonu ve Karakterizasyonu

Author(s):  
Yasemen Yanar ◽  
Mehmet Gökçin

The aims of this study were to determine the physicochemical properties of extracted gelatins from mackerel (Scomber scombrus) and sea bass (Dicentrarchus labrax) bones and compare with those of commercial fish and bovine gelatins. The yield of gelatin obtained from the bone of mackerel and sea bass were 5.98 and 6.20%, respectively. Two extracted gelatins showed higher protein content, lower moisture content compared to both commercial gelatins, indicates that the gelatin has considerably high purity. Melting temperatures of mackerel and sea bass bone gelatins were 25.5 and 23°C, respectively. Mackerel bone gelatin was yellow in appearance and higher L* value than both commercial gelatins. It can be concluded from the present study that mackerel and sea bass bone are a prospective source to produce gelatin in good yield with desirable functional properties comparable to commercially available mammalian and fish gelatins.

Author(s):  
A. Legrouri

The industrial importance of metal catalysts supported on reducible oxides has stimulated considerable interest during the last few years. This presentation reports on the study of the physicochemical properties of metallic rhodium supported on vanadium pentoxide (Rh/V2O5). Electron optical methods, in conjunction with other techniques, were used to characterise the catalyst before its use in the hydrogenolysis of butane; a reaction for which Rh metal is known to be among the most active catalysts.V2O5 powder was prepared by thermal decomposition of high purity ammonium metavanadate in air at 400 °C for 2 hours. Previous studies of the microstructure of this compound, by HREM, SEM and gas adsorption, showed it to be non— porous with a very low surface area of 6m2/g3. The metal loading of the catalyst used was lwt%Rh on V2Q5. It was prepared by wet impregnating the support with an aqueous solution of RhCI3.3H2O.


This study concentrated on the assessment of the prevailing parasitic fish diseases in some marine fishes at Ismailia province and how to control the infestation using microalgae. This study was carried out on 1080 pre-mature fish (360 D. labrax (225±25 g) and 360 S aurata (150±25 g) and 360 M. cephalus (125±25 g) collected from similar ponds of studies to be examined at the end of treatment. In addition to that we followed non-treated fish (1080 premature). The infested fish showed dark colour and respiratory signs. Post mortem lesions were a presence of congestion or paleness and destruction of gill filaments. The total prevalence of infestation was the total prevalence of parasitic infection of non-treated fishes was 45.83 %. The highest percentage was in D. labrax 56.94 % followed by S. aurata 47.22%, the lowest percentage in M. cephalus 33.33. The total prevalence of parasitic infection in premature treated with 2 g algae was 28.79%, followed by 3 g algae was 23.60 %, while the lowest percentage with 5 g algae was 20.37 % respectively. The detected species of parasites were protozoal parasites, Amyloodinium ocellatum and Riboscyphidia in additions of marine monogenea, Lamellodiscus diplodicus isolated from D Labrex, Mugil Cephalus and S aurata. The present study concluded that, the use of microalgae instead of fish meal decreased parasitic infestation in marine fish. The histopathological alteration of natural infested examined fishes was also recorded.


2019 ◽  
Vol 90 ◽  
pp. 317-327 ◽  
Author(s):  
Shay Ravid-Peretz ◽  
Angelo Colorni ◽  
Galit Sharon ◽  
Michal Ucko

Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 392
Author(s):  
Lydia Katsika ◽  
Mario Huesca Flores ◽  
Yannis Kotzamanis ◽  
Alicia Estevez ◽  
Stavros Chatzifotis

This study was conducted to elucidate the interaction effects of temperature and dietary lipid levels (2 × 2 factorial experiment) on the growth performance, muscle, and liver composition in adult farmed European sea bass (Dicentrarchus labrax). Two groups of fish (190 g; 60 fish per group) were distributed in 12 tanks in triplicates and kept at two different temperature regimes; one starting at 23 °C and then changed to 17 °C for 61 days, and the other starting at 17 °C and then changed to 23 °C for 39 days. Two commercial diets containing both ~44% crude protein but incorporating different dietary lipid levels, 16.5% (D16) and 20.0% (D20) (dry matter (DM)), were fed to the fish to apparent satiation; the type of diet fed to each fish group remained constant throughout the experiment. Final body weight, weight gain, and specific growth rate were significantly higher for the fish group held at 23 °C compared to the fish group at 17 °C (before the temperature changes), while the dietary fat content did not have any profound effect in both groups. Furthermore, the different temperature regimes did not affect muscle or liver composition, but, on the contrary, dietary lipids affected hepatosomatic, perivisceral fat, and visceral indexes. Feed conversion ratio and specific growth rate were not affected by the dietary lipid level. An interaction of temperature and dietary lipid content was observed in daily feed consumption (DFC) and final body weight (FBW).


2017 ◽  
Vol 19 (1) ◽  
pp. 102-115 ◽  
Author(s):  
Daniel Żarski ◽  
Thaovi Nguyen ◽  
Aurélie Le Cam ◽  
Jérôme Montfort ◽  
Gilbert Dutto ◽  
...  

Aquaculture ◽  
2021 ◽  
Vol 537 ◽  
pp. 736458
Author(s):  
Cheng Zhou ◽  
Zhi-qiang Zhang ◽  
Lei Zhang ◽  
Ying Liu ◽  
Peng-fei Liu

Aquaculture ◽  
2021 ◽  
pp. 737257
Author(s):  
A. Samaras ◽  
A. Dimitroglou ◽  
S. Kollias ◽  
G. Skouradakis ◽  
I.E. Papadakis ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document