نشریه پژوهش های علوم و فنون دریایی
سال دوازدهم شماره 1 (بهار 1396)

Fatty acids profile of phytoplankton was studied in the spring and summer in the Caspian Sea in 1394, in order to evaluate seasonal changes. Sampling was performed in three repetitions, for each season (noshahr area). The volume of water that filtered by filtration device was about 25 liters. The profile of fatty acids for samples were obtained by GC/mass. The results that were related to the profile of fatty acids in the spring and summer showed that the overall percentage of saturated fatty acids (SFA) were %54.5 and %32.3, respectively. Mono unsaturated fatty acids (MUFA) were %30.22 and %37.39 and poly unsaturated fatty acids (PUFA) were %15.31 and %16.67, respectively. It was observed that SFA in the spring, MUFA and PUFA in the summer showed high levels. Some of the essential fatty acids such as Omega-3 (EPA and DHA) that play a main role in the food chain and human health increased in the summer. Statistical analysis suggested that there was no significant difference between spring and summer for total fatty acid groups, but some important fatty acids, such as Palmitic acid, Oleic acid and DHA, showed significant difference between two seasons.

This study was done in order to determine the concentration of heavy metals Nickle, Cadmium and Lead in the muscle of Acanthopagrus latus and Platycephalus indicus from Oman Sea (Chabahar Bay) in spring, summer and fall of 2013. In this study 48 samples of fishes were obtained from coastal and marine regions of Oman Sea (Chabahar Bay). Metals were extracted from the tissues using wet digestion method and concentration of heavy metals were measured by Younglin AAS8020 Atomic Absorption Spectrophotometer. The highest concentration of Cd, Pb and Ni were found in the muscle of Platycephalus indicus which were 0.052±0.02, 0.047±0.02 and 1.768±0.96 mg kg-1. The lowest concentration of Cd, Pb and Ni were obtained in the muscle of Acanthopagrus latus which were 0.019±0.01, 0.010±0.01 and 0.466±0.02 mg kg-1. Concentration of Cd, Pb and Ni in the two fishes from coastal zone was higher than marine area. Concentration of heavy metals in the muscle of Acanthopagrus latus and Platycephalus indicus in summer was higher than spring and fall. Concentration of Ni in the two fishes was higher than Cd and Pb. Concentration of Cd and Pb in the muscle of Platycephalus indicus from coastal and marine zone in spring, summer and fall was higher than Acanthopagrus latus, but concentration of Ni in the muscle of Acanthopagrus latus was higher than Platycephalus indicus. Concentration of Cd and Pb was lower in comparison with levels recommended by FAO, WHO, UKMAFF, NHMRC and FDA, but concentration of Ni was higher in comparison with international standards.

This study was conducted to introduce and classify the costal habitats of Hormuz Island. In the initial survey, the natural and anthropogenic features of the coastline were recorded by GPS and then seven stations were designated. The results showed that the coast line is divided into three main geological substrate types: rocky-sandy (52%) with total of 19.76 km length of coastline, rocky and muddy, with 40% (15.2 Km) and 8% (3.04 Km) of total coast line, respectively. Furthermore, all the coastline’s and station’s geomorphologies were surveyed independently and 20 different coastline habitats were identified. The results also showed that, Hormuz Island shoreline is divided into north and south major substrates because of sedimentation activities. The main hard substrate is located in the south coasts and the main soft substrate is located in the north. Shoreline habitat’s opportunities and threats were investigated and the results indicated that, the sensitive coastline habitats in this island require management, control and biological assessments under a purposeful management plan.

Biological, chemical and physical factors influence on physiology of aquatic microalgae. Changes in these factors effect and disturb the life cycle of microalgae as well as their physiological parameters.In this study the changes of pH in the culture medium of green algae Scenedesmus quadricauda (Turp.)‌Bréb. In three different culture media under chemical stresses using herbicideMetribuzin and water hardness, was investigated. The experiment was conducted in a completely randomized design for a period of 21 days. Change in acidityof culture media A and B had direct relationship with water hardness and presence of herbicide. Results of pH changes in medium A suggest a direct correlation with the amount of chlorophyll a,‌ b and carotenoid. According to the results of analysis of variance, there are also significant differences (P < 0.05) in some treatments in different media. The greatest amount of carotenoid was observed at 150 mg/L CaCO3. In general, it can be said that the green algae, Scenedesmus quadricauda species, had high tolerance to changes in the acidity of the medium, along with chemical stresses caused by water hardness and presence of herbicide Metribuzin.

This study was carried out to compare the effect of two commercial prebiotics (A-Max concentrate and A-Max Ultra) on growth performance and resistance of common carpfry. This experiment was conducted in a completely random design with a total number of 1080 apparently healthy carp fry (initialaverage weight of 1.3±0.304 g), which were caught and transferred to the laboratory. After 7 days of adaptation to the laboratory conditions, the fish were randomly divided into 9 treatments in 27 polyethylene tank (40 carp fries per tank) in triplicates. The carp fries were fed with four concentrations of 0.3, 0.5, 0.7 and 1 g kg-1 prebiotics in-feed and the control was fed with diet without prebiotic supplementation, for 60 days. At the end of the study the results indicated that growth performance parameters and feed efficiency were highly significantly (p<0.05) different in probiotic A-max concentrate treatment, especially treatment A4 (1 g kg-1 prebiotic), in comparsion with other treatments and control group. The same trend was observed for survival rate (p<0.05). Similarly, significant differences were observed in resistance against environmental stresses in all treatments compared with control group (p>0.05). These results suggested that supplementing diets with commercial feed additives, A-Max concentrate and A-Max Ultra, promotes growth performance, feed efficiency and increased larvae resistance against the challenge tests compared with the control group, but the comparison between them showed that A- max concentrate was more superior at 1g kg-1 in common carp fry diets.

Antioxidant is a substance which inhibits production of free radicals, autooxidation in foods and cancers. This study focuses on the antioxidant property and polyphenol compounds of enriched jelly gums enriched with green microalgae Chlorella vulgaris. Moisture, ash and acidity of samples were also evaluated. Jelly gums were produced with different amounts of dried powder of green microalgae Chlorella vulgaris. Antioxidant property of microalgae and products were evaluated by DPPH and polyphenol compounds were evaluated by folin-ciocalteu assay. Moisture, ash and acidity were compared with standards for jelly gums. According to the results, jelly gums hadsignificant antioxidant properties because of Chlorella vulgaris which was27 ± 0.3 mg gallic acid g/dw. This microalga contains the acceptable level of polyphenol compounds and also about 2 ± 1.3 mg equivalent gallic acid g/dw. Moisture was stable in all samples and equal to 12.2. Ash was increased in each evaluation but acidity was decreased every time. Comparing the results of antioxidant properties of these samples with different groups of foods in other studies, it can be perceived that the samples are in the category of high antioxidant property. Using green Chlorella vulgaris assures the presence of polyphenol compounds in the products. Neither moisture, ash nor acidity were non-compliant with the standards.

The aim of this study was to evaluate the toxicity effect of lead heavy metal on some serological parameters on Silver Carp in the vicinity with lead for a short term. In order to do this study a total of 135 fish with mean weight of 50±10 gand mean length of 13±1 cm were placed in adjacent to 0, 5 and 10 mg/l of Pb (NO3 )2 in 9 aquariums of 90 liter capacity.Sampling was done randomly each 12 hours for 96 hours from caudal vein of the fishes. The results showed that there was a significant difference in the amount of hemoglobin in 24 hours, between the control and treatments. The level of glucose was increased significantly by increasing the concentration of lead and passing of the time. The levels of triglyceride and albumin did not change significantly (P>0/05). The level of cholesterol increased significantly until 72 hours and after that decreased significantly. Amount of total protein increased significantly by increasing the concentration of lead and time. Based on the results, biochemical parameters are useful for monitoring of lead acute toxicity in Silver Carp.

In this study, the distribution of macrobenthos in Boojagh Marine National Park (BMNP) was studied. Sampling was conducted in six transects, perpendicular to the beach, using a Van Veen grab sampler, with five replications. Samples were collected in five seasons (2015-2016). Each transect include three stations at depths of 1 meter, 5 meter and 10 meter. Washed and fixed samples were transferred to the laboratory, sorted and different groups of microbenthic taxons were identified. Mollusca with an average of 588 individuals per square meter, Malacostraca with 225, Polychaeta with 175, Hexanauplia with 109 and Clitellata with 98 individuals per square were identified. Depth profiles showed that the benthos are mostly distributed at 10 meter depth, followed by five and one meter depths. The densest season was at summer of 2015, with 356 individuals per square meter followed by summer of 2016, autumn and winter of 2015 and spring of 2016. Overall, the most macrobenthos distribution was in 10 meter depth. Macrobenthos density in the summer was more and in the spring was less than other seasons.