Determination and study the fatty acid contents and their seasonal variations by temperature of a dominant bivalve (Callista umbonella) of Haleh Creek

In this study fatty acid contents, because of the importance in human’s life, and their seasonal variations of a dominant bivalve of Haleh Creek were determined for the first time. Fatty acid identification was done by GC-MS (Gas Chromatography–Mass Spectrometry) method. After collecting and dissecting the species from the shells, samples were weighed and frozen for further experiments. All the samples esterified and made ready for injection to the GC-MS. Temperature as an important environmental parameter monitored monthly, variability of the fatty acid components studied in two seasons, and the effect of temperature changes on seasonal variations of the fatty acids were studied by statistical analysis. In conclusion sixteen fatty acids were identified in Callista umbonella, including twelve saturated and four unsaturated, which the most important were oleic, palmitic, myristic, hexadecanoic and nonadecanoic acids while saturated fatty acids were dominated over unsaturated ones. The most abundant saturated fatty acid was palmitic acid and unsaturated one was oleic acid in this species. Although fatty acids’ seasonal changes did not show any significant difference and also any significant correlation with temperature in the species in this area, but in general fatty acid amounts might be vary in different temperatures and it could be related to many environmental and biological factors in species

The effect of dry salting on the shelf life of big mouth saury (Scomberoides commersonnianus)

The present study investigated the effects of salting process on shelf life of big mouth saury (Scomberoides commersonnianus) filets. To determine the quality, chemical experiments including crude protein, peroxide value, crude lipid, ash-salt and moisture measurements were conducted at time intervals of 0, 15, 30, 90, 150 and 190 days. Moreover, fatty acid profile was measured at time intervals of 0, 90 and 190 days. Mean (±SD) crude protein, crude lipid, ash-salt and moisture contents in fresh fish were 20.07±0.85, 6.32±0.42, 2.17±0.2and 71.44±0.19, respectively, reaching 30.5±1.19 8±0.12, 17.6±0.1 and 43.9±0.91, respectively, after salting and storing at the ambient temperatures for 190 days. The mean (±SD) peroxide was 0.05±0.01 meqO2 kg-1, and in fresh fish reached to 2.5±0.05 meqO2 kg-1 at the end of storage time as salted products. Variations in all of these factors were significant. According to the obtained results, the best time period for storing is 90 days. In the present study, 21 fatty acids were recognized. Total saturated, and unsaturated fatty acids in fresh samples (time 0) were 53.41 and 54.47%, respectively, and reached 56.99 and 39.92 at the end of storage time as the salted product. The result of the organoliptic showed that the new method of the dry salting give a better quality to the product in comparison with the traditional method of dry salting

Short communication: Using polychaetes as an assessment tool for health status of Jafari Creek, north-west of the Persian Gulf

Marine ecosystems and their adjacent coastal habitats, especially estuaries are important because of maintaining the coastal biota, including a diverse array of organisms. However, these ecosystems are being impacted by the anthropogenic activities through urbanization and industrialization developments. For evaluating the degree of alteration occurring in these valuable ecosystems, scientists have conducted several methodologies based on chemical assays (i.e. directly measured abiotic parameters of the environment) and use of ecological indices. ... In this regard, the present paper was prepared to evaluate the health status of Jafari Creek using polychaetes as indicators and to compare the results with the previous evaluation which had been done through tracing the spatial distribution of the whole macrobenthic assemblages and chemical assay of the ambient factors in this area. Accordingly, the primary objective of this research is to introduce the status of polychaetes assemblage of Jafari Creek and furthermore provide answer to this question if analysis of the polychaete fraction of the macrobenthic community of the creek can be a useful key in interpretation of the effects of industrialization

Spatial distribution and assemblage structure of foraminifera in Nayband Bay and Haleh Estuary, north-west of the Persian Gulf

The spatial distribution of benthic foraminiferal assemblage of Nayband Bay and Haleh Estuary in the North-West of the Persian Gulf, was explored during 2011-2012. The relationship between spatial pattern of foraminifera assemblages and the ambient factors (i.e. water temperature, salinity, pH, dissolved oxygen, sediment grain size distribution, sediment organic content, and CaCO3 concentration of sediments) was measured. The most abundant benthic foraminifera species which were found in the studied area include Ammonia beccarii, Eponides repandus, Quinqueloculina sp., Elphidium sp. The two most abundant species belongs to Rotaliidae family. The specimen groups presented in the study area were somehow the same, and their relative abundance did not vary tremendously in sites consisting of foraminifera assemblages. The fauna shows affinities to those of the southern coastline of the Persian Gulf and also the Oman Sea. The BIO-ENV analysis identified temperature, salinity, pH, and total organic matter as the major environmental variables influencing the infaunal pattern. Generally foraminiferal populations were sparse in the study area, which may be due to the low depth and consequently, low distribution of foraminiferal specimens

Growth comparison between post-larvae from cultured and wild spawners of Indian white shrimp, Penaeus indicus, in commercial farms in north Persian Gulf, Bushehr, Iran

Post larvae of wild and cultured spawners of the Indian white shrimp (Penaeus indicus, Milne Edwards, 1837) were reared to market size, in commercial ponds of shrimp farming site of Helleh, in Bushehr Province, during a six months period. Environmental factors, management process and the diet used to feed shrimps were almost similar for both treatments. Averages of the weight, length, specific growth rate, food conversion ratio and survival rate were measured and compared between the two treatments at harvesting time. Results indicated that, the post larvae of wild spawners had better growth, higher survival rate, and lower food conversion ratio. Weight gain of abdominal portion of the body, was higher in wild post larvae (P<0.01), which was in contrast to cephalothorax weight (P<0.01). Length-weight relationship measurements illustrated that, cultured post larvae obtained from wild spawners had similar size and were more acceptable for the market. Broodstock background could be the main reason for given differences, in which, those captured from the sea, had better condition due to receiving appropriate food with higher genetic diversity. To produce high quality post larvae for the expanding shrimp farming industry as an economic activity in the country, it is suggested that broodstocks to be obtained either from the sea as sub-adults or matured spawners, or to be provide from culturing shrimps, raised in conditions closest to the nature (i.e., ambient factors, prepared diets) and also with appropriate genetic diversity

Spatial distribution and assemblage structure of macrobenthos in a tidal creek in relation to industrial activities

The impact of petrochemical special economic zone activities on the health status of Jafari Creek was studied by assessing the changes in macroinvertebrate assemblages in nine sites during September 2006- January 2008. The relationship between spatial pattern of macroinvertebrate assemblages and ambient factors (i.e. water temperature, salinity, pH, dissolved oxygen, sediment grain size distribution, sediment organic content, heavy metals contents) was measured. Background enrichment indices, contamination factor and contamination degree, were used to assess the health status in the study area based on nickel, lead, cadmium and mercury contents of the sediments. The macrobenthic communities had a low diversity and were dominated by opportunistic taxa. The BIO-ENV analysis identified salinity, dissolved oxygen, pH and silt/clay content of sediments as the major environmental variables influencing the infaunal pattern. This suggests that management should attempt to ensure minimal disturbance to environmental variables underlying the spatial variation in macroinvertebrate assemblages. Background enrichment indices showed that the health of Jafari Creek has declined over time due to the constant discharge of heavy metals to the Creek system. These indices also identified a significant degree of pollution in the study area. The decrease in the ecological potential of Jafari Creek was best highlighted by the alteration in macrobenthic assemblages