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Talab H.A.,Islamic Azad University at Tehran | Ardjmand M.,Islamic Azad University at Tehran | Pourgholam R.,Caspian Sea Ecology Research Center
Nutrition and Food Science | Year: 2010

Purpose: Extraction and purification of Hypophthalmichthys molitrix fish oil by urea complex formation were made at -5, +1 and +5°C, respectively. Omega-3 polyunsaturated fatty acids (PUFA) have proved to be beneficial in atherosclerosis, arrhythmia and hypertriglyceridemia. Starting with the hypothesis that the observed low cardiovascular morality could be related to marine diet, which contains omega-3 PUFA. Design/methodology/approach: Fish oil was extracted by Bligh and Dyer method from the muscle tissue and after, the PUFA concentrates produced by urea complexation and the oil samples were stored at -70°C. The observed results show that the rate of omega-3 extraction has been increased while saturated and long chain monosaturated fatty acids decreased during this process. Findings: Eicosapentaenoic acid (EPA) has a higher tendency to form urea adducts than the other two major n-3 PUFAs, especially at low temperatures. The optimum temperature for maximum recovery of EPA is about 1°C. The amount of extracted omega-3 in H. molitrix oil were 20.58 per cent wt of total extracted oil and by subsequent purification increased to 68 per cent wt at 1°C, 36.82 per cent wt at +5°C and 22.53 per cent wt at -5°C of total extracted oil. Practical implications: Omega-3 PUFA have proved to be beneficial in atherosclerosis, arrhythmia and hypertriglyceridemia. Starting with the hypothesis that the observed low cardiovascular morality could be related to marine diet, which contains omega-3 PUFA. In order to reduce the risk of cardiovascular diseases, emphasis has now been placed on the increased consumption of fish and fish products which are rich in PUFA. Originality/value: The amount of extracted omega-3 in H. molitrix oil were 20.58 per cent wt of total extracted oil and by subsequent purification increased to 68 per cent wt at 1°C, 36.82 per cent wt at +5 °C and 22.53 per cent wt at -5°C of total extracted oil. Due to the low price of H. molitrix in comparison to other ocean fish sources, as well as, its availability in all seasons, higher level of ω3-fatty acids, H. molitrix species has a good potential for ω3-fatty acids production by extraction and subsequent purification. © Emerald Group Publishing Limited. Source


Ejraei F.,Islamic Azad University at Lahijan | Ghiasi M.,Caspian Sea Ecology Research Center | Khara. H.,Islamic Azad University at Lahijan
Archives of Polish Fisheries | Year: 2015

The aim of this study was to assess the changes in hematological and plasma indices of Ctenopharyngodon idella (Val.) with regard to age, sex, and hormonal treatment. Sixty specimens of C. idella, comprising fifteen of each age (6, 12, 24, and 36 months) were used to evaluate the age factor. Additionally, 20 fish, both females and males, were designated to determine blood indices with regard to sex and hormonal treatment. The following biochemical indexes were determined in the blood plasma: glucose, cholesterol, triglycerides, and total protein (TP). Glucose and triglyceride levels differed significantly among ages, and significant age-related differences were noted in the values of red blood cell (RBC), white blood cell (WBC), hemoglobin (Hb), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC). There were no significant differences in any parameters between males and females. In conclusion, our results showed that the plasma parameter profile could be affected by age (RBC, WBC, Hb, MCV, MCH, MCHC, glucose, triglycerides) and hormonal treatment (lymphocytes and eosinophils). The blood plasma biochemical and hematological profiles permitted assessing physiological state, which provided useful information for monitoring changes in the health status of the fish. © Copyright by Stanislław Sakowicz Inland Fisheries Institute in Olsztyn. © 2015 Author(s). This is an open access article licensed under the Creative Commons Attribution-NonCommercial-NoDerivs License. Source


Karimzadeh G.,Mazandaran Province Fisheries Administration | Gabrielyan B.,Armenian National Academy of Sciences | Fazli H.,Caspian Sea Ecology Research Center
Iranian Journal of Fisheries Sciences | Year: 2010

The aim of the present study was to investigate the age structure, length-weight relationship, sex ratio, sexual maturity stages, growth parameters, natural and fishing mortality coefficients of three species of kilka, including common, anchovy and bigeye kilka. The fork length-weight relationship of common, anchovy and bigeye kilka were calculated as W=0.000153 FL 2.37, W=0.000349 FL 2.18 and W=0.00160 FL 2.97, respectively. The parameters of the von Bertalanffy growth curve for length were L ∞ = 143.5 mm, K = 0.30 yr -1 and t 0 = -1.02 yr for common kilka; L ∞ = 151.9 mm, K = 0.28 yr -1 and t 0 = -1.12 yr for anchovy kilka and L ∞ = 148.6 mm, K = 0.46 yr -1 and t 0 = -0.18 yr for bigeye kilka. The instantaneous coefficient of natural mortality of common, anchovy and bigeye kilka were estimated as 0.671, 0.633 and 0.881 yr -1, respectively. The current exploitation rates of three species were estimated as 0.55, 0.41 and 0.26 for common, anchovy and bigeye kilka, respectively. The results suggest that common kilka stock is under over-fishing now. Source


Salman M.A.,Gorgan University of Agricultural Sciences and Natural Resources | Fendereski F.,Gorgan University of Agricultural Sciences and Natural Resources | Hosseini S.A.,Gorgan University of Agricultural Sciences and Natural Resources | Fazli H.,Caspian Sea Ecology Research Center
Indian Journal of Marine Sciences | Year: 2013

Chlorophyll-a data of the MODIS sensor with in-situ chlorophyll measurements from the southern Caspian Sea (SCS) is compared in the present study. Analysis showed an overestimation of chlorophyll-a concentration by MODIS in the area. Results also indicated a root mean square (RMS) log error of 39.4%, for 53 coincident data points. An artificial neural network (ANN) with radial basis function was applied to the in-situ measurements and satellite imagery. It included physical-chemical properties of water as ancillary independent variables in the ANN procedure that enhanced the predictive capability of the model. Evaluation of the predictive capability of ANN approach was satisfying (RMS log error 18.9%). Results showed retrieving chlorophyll-a concentration in the SCS from satellite is possible and will be improved through application of ANN and explanatory environmental parameters. Source


Leroy S.A.G.,Brunel University | Lahijani H.A.K.,Iranian National Institute for Oceanography | Reyss J.-L.,CEA Saclay Nuclear Research Center | Chalie F.,Aix - Marseille University | And 13 more authors.
Quaternary Science Reviews | Year: 2013

Dinoflagellate cyst assemblages were analysed in four short sediment cores collected in the south Basin of the Caspian Sea for assessing environmental changes over the last few millennia.Two of these cores were dated by radionuclides. The sedimentation rate of one of them was very high, in the order of 20mm per year. The interpretation of the four sequences is supported by a collection of 27 lagoonal or marine surface sediment samples. A sharp increase in the concentration of the dinocyst occurs after 1967, especially owing to Lingulodinium machaerophorum. Considering nine other cores covering parts or the whole of Holocene, it became clear that this species started to develop in the Caspian Sea only during the last three millennia. By analysing instrumental data and collating existing reconstructions of sea level changes over the last decades, we show that the main forcing for the recent increase of L.machaerophorum percentages and concentration is global climate change, especially sea surface temperature increase. Sea level fluctuations likely only have a minor impact. We argue that the recent increase in L.machaerophorum indicates that the Caspian Sea clearly is in the Anthropocene. © 2013 The Authors. Source

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