JOURNAL OF MARINE BIOLOGY
Year:2017 | Volume:8 | Issue:32|Papers Count:10

This study was conducted to evaluate the effects of using Artemia fransiscana enriched with cod liver oil and vitamin C on growth, survival and stress resistance caused by salinity and temperature fluctuation of Sepia pharaonis larvae. 25 days after hatching the larvae of Sepia pharaonis were transferred into culture tanks with average length of 15.97±0.15 mm, 3.53±0.03 gr body weight in five treatments (each with 3 replicates). Experimental treatments including: Artemia fransiscana enriched with cod liver oil at different levels of C1= 5%, C2= 10% and C3=15% vitamin C, non-vitamin cod liver oil, and control (non-enriched artemia) group. In each replicate, the 20 larvae were introduced into tanks of 20 liters and 10 artemia /liter/ days to feed larvae were used. At the end of experiment, to investigate stress resistance, three groups of larvae were encountered at one hour stress with 5, 15, 25 ppt salinity, and 10, 25, 32 °C temperature levels. Results indicated that although the survival rate showed no significant difference between treatments (except control) but was higher in salinity 25 ppt and in 25 °C. Generally, results showed that feeding with vitamin C and unsaturated fatty acids elevated survival rate and growth factors in Sepia pharaonis larvae.

Escherichia coli belong to a group of bacteria called coliform which is member of Entrobacteriacea family. For many years, the bacterium are using as fecal indicator for public health. Escherichia coli are as an important organism which could disseminate antibiotic resistance in water shoreline. Accordingly, the present study tried to isolate the bacterium from Genaveh shoreline and sediments. Then phylogenetically categorized based on Clermont technique and evaluate their antibiotics pattern. For this purpose, 60 samples (30 water and 30 sediment) were collected from water and sediments between April to August 2016. Then the samples were evaluated by MPN technique and for confirmation they were cultivated on MacConkey and Eosin methylene blue agar. After that they were identified using Gram stain, Catalase and oxidase tests. The phylogenetical analysis of E.coli was done using set of primers: ChuA, yjaA, TSPE 4.C2 and antibiotic pattern were assessed using antibiogram test. Out of 60 collected samples, 6 samples were identified as E.coli, 5 from water and 1 from sediments. Based on antibiogram test all of the isolates with 100% were sensitive to Gentamicin, Ceftriaxone and Cefotaxime. The most common phylogenic group was belonging to groups A, B2 and D. Based on elucidated results it could be concluded that the best antibiotic on the isolates were Gentamicin, Ceftriaxone and Cefotaxime. Therefore, suggesting for remedy of gastrointestinal infections caused by Escherichia coli the selected antibiotics could be use along with other techniques in this geographical area.

Histopathological changes in the liver and gills of grey mullet (Mugil cephalus L.) fed with diets containing amino-acid L-cysteine and exposed to heavy metals copper and zinc was investigated in 2016 at Chabahar Maritime University. The aim of this research was the determining of the effects different concentrations of amino-acid L-cysteine on the liver and gill tissues of grey mullets, against the pollution of these metals. For this purpose 300 grey mullet juveniles with an average weight of 27.4±3 g were captured from the coastal waters of Chabahar Bay, and after adaptation to the laboratory conditions and artificial feeding, were divided into seven treatments (one control group, three cu treatment and three Zn treatments). In this study, the experimental fishes were exposed to heavy metals Cu and Zn (20% more than their natural concentration in the coastal waters of the University), and fed with four diets containing (0, 25, 50 and 100 percentage) of cysteine relative to the cysteine content of the basal diet for 45 days. At the end of culture period (45 days) random tissue samples from the gills and liver of all treatments were taken, and after dehydration, fixation in paraffin, discoloration and clearing were stained by hematoxylin and eosin solutions. The results of microscopic observation of prepared samples revealed that the severity of tissue damage in treatment three (with 100% cysteine) was the most; while in treatment one (with 25% cysteine) was the least compared with other treatments. Moreover, the diet containing 25% cysteine was more efficient compared to the other diets with higher cysteine content (50 and 100%), in terms of severity of damages, while in the higher concentrations of cysteine, the severity of damages was intensified concurrent with the effects of the heavy metals. Therefore, the obtained results proved that the amino-acid cysteine improves the detoxification process by influencing the metabolism of metals in fish, and reduction of the harmful action of heavy metals on the histopathological changes of the liver and gills. Besides the liver and gill tissues can be used as suitable indicators for the assessment of histopathological changes inflicted by heavy metals in mullet fishes.

Extensive increase of phytoplankton is considered as a threatening factor in marine ecosystems by influencing food networks and biodiversity. Increase of minerals and nutrient due to human activities cause abnormal increase of this microorganism. As a result, phytoplankton biomass monitoring can be used as an effective method for identifying marine ecosystem from human activity pressure and eutrophication. In this study SeaWiFS and MODIS Aqua data were used for the study area. After preprocessing of chlorophyll-a and SST data and extracting time series algorithms of these data from 1998 to 2015, rate of the changes calculated by median trend. Result of this test showed that amount of chlorophyll-a concentration in the investigation surface water area from 1998 to 2015 have increasing trend (0.02 mg/m3) and also SST (Sea Surface Temperature) increased 0.11°C. Also, result showed good correlation between a concentration and Mnemiopsis leidyi (R2=0.65). In other words, amount of chlorophyll a Concentration in the alga bloom area is more than another area. In hence, one of the most important in chlorophyll a is algal blooms.

The present study aims to examine and identify zooplanktons species carried by ballast tanks of the ship and discharged into Bandar Imam Khomeini waters. The samples were taken during summer 2014 from 12 ships loaded with ironstone, condensate and ironware traveled from both South America and the Southeast Asia within two seasons. For this purpose, 50 liter-three specimens was filtered by a 100 micron plankton catching net and stabilized by formalin. The specimens were detected by microscope and by using the valid identification keys. Considering to the obtained results within two seasons of summer and winter, it is found that there were totally 9 families and 18 genera transported through South America route where the greatest frequency was related to Paracalanidae with 35%, whereas in the Southeast Asia route there were 18 families and 30 genera of zooplanktons in which the greatest frequency was found in Cyclonidae and Sididae families with 9 and 8%, respectively. By comparing both local and foreign reports related to this zone it was revealed that no species can be regarded as invasive species.

Most of the marine invertebrates same as sponges and sea cucumbers which provide secondary metabolites with pharmacological application. In this study, antibacterial activities of methanol extracts of sea cucumber H. leucospilota and sponge N. furcata were assessed by Bacterial Broth Dilution Methods against strains of gram positive and gram negative bacteria. Our results showed methanol extract of N. furcata was active on Gram-positive and gram negative bacteria. The Minimum Bacterial Concentration of Method extract of N. furcata was 5 mg/ml for Bacillus subtilis spizizenii, 10 mg/ml for Staphylococcus aureus aureus and Bacillus cereus, 30 mg/ml for Escherichia coli and 20 mg/ml for Serratia marcescens. But methanol extract of H. leucospilota did not show good activity against these bacteria. The Minimum Inhibitor Concentration of Method extract of sea cucumber was 30 mg/ml for Bacillus subtilis spizizen and Bacillus cereus, 10 mg/ml for Staphylococcus aureus aurous, 30 mg/ml for Escherichia coli and 10 mg/ml for Serratia marcescens. The Minimum Bacterial Concentration of Method extract of H. leucospilota was 40 mg/ml just for Staphylococcus aureus. Methanol extract of N. furcata in comparison with H. leucospilota had better activity against bacteria; therefore, secondary metabolite solutions in methanol extracts of N. furcata contain components with antibacterial properties and can be used as antibiotics products.

This study was carried out to compare proximate composition and fatty acid profile in muscle of wild and cultured Beluga sturgeon (Huso huso). Total of four 3-year cultured Beluga specimens (average weight 7.0±0.4 kg) and four 3-year wild Beluga specimens with the similar weight were obtained and 1.5 kg of the dorsal body muscle form each specimen dissected. The muscles were minced and used in triplicate for determination of moisture, crude protein, crude fat, and ash content in each specimen. Crude fat of the same samples after extraction and esterification were used for identification of fatty acid composition in each fish. Comparison between the data of wild and cultured Beluga was done using T-test in significance level of less than 5 percent. There were no significant differences in the amount of protein and ash in Beluga muscle (P>0.05), while moisture and fat of cultured Beluga muscle with the amounts of 71.52±8.13 % wet weigh and 5.25±0.10% dry weight were significantly higher and lower than that in wild specimens, respectively (P<0.05). Besides, amount of palmitic acid, Myristic acid, and Docosapentaenoic acid in the cultured Beluga muscle was significantly higher than that in wild specimens, whereas erucic acid of wild Beluga was significantly higher than that in cultured one (P<0.05). No significant difference was observed in the amount of other fatty acids between wild and cultured Beluga muscle (P>0.05). Results of the present research illustrated that muscle of cultured Beluga had the same and in some cases higher nutritional value than wild Beluga.

Acid soluble collagen (ASC) and pepsin soluble collagen (PSC) were extracted from mixture tissues of three abundant species of kilka fish such as common kilka (Clupeonella cultriventris), Anchovy kilka (Clupeonella engruliformis) and big eye kilka (Clupeonella grimmi (in the Caspian Sea. The samples were collected from fish landing site (Amirabad harbor) in the Mazandaran province. The fish were caught nightly by conical lift and transported in ice to the laboratory for collagen extraction. Non-collagenous proteins and fat of 15g mixture tissue of different organs were isolated by 0.1M NaOH and 10% Butyl alcohol solutions, respectively. Collagen was extracted by acidic and enzymatic methods at 4 °C. In the next stage, collagen precipitates with NaCl and purification to 0.1M acetic acid solution and distilled water. The results showed that collagen of Clupeonella grimmi has the highest value of 4.14%, Clupeonella cultriventris and Clupeonella engruliformis have 1.04%, 0.94% on a dry weight respectively. The SDS-PAGE pattern showed that the ASC and PSC produced from this three species have hetrotrimer structure and made of two chains; a1 and a2. The extracted collagen is considered type I. Therefore, kilka fish especially Clupeonella grimmi can be used as a source for industrial and medical procedures. According to the results, kilka fish can be a commercial source in the Caspian Sea.