10 research outputs found
Evaluation of antioxidant activity of the purified peptides from hydrolysis of rotifer (Brachionus plicatilis)
Rotifers are an important group of zooplankton in aquatic ecosystems that contain relatively high amounts of unsaturated fatty acids, proteins and peptides. Rotifers, especially Brachionus plicatilis species, are one of the important live food sources for marine fish larvae in aquaculture. The aim of this study was to evaluate the antioxidant activities of purified peptides from B. plicatilis. Antioxidant peptides of the B. plicatilis have been hydrolyzed by Alcalase, α¬Chymotrypsin, Papain, Neutrase, Pepsin, and Trypsin. Their antioxidant activity was evaluated by the free radical inhibitory effect of diphenylpicrylhydrazyl (DPPH). Also the sequential chromatography method was used for extraction and purification of the peptides. The results showed that peptides obtained from the pepsin hydrolysate have a higher inhibitory effect than other peptides. Pepsin showed 58% inhibitory effect in 0.015 mM DPPH. Finally, the pepsin hydrolysate constitutes were purified and isolated by gel-filtration chromatography (Sephadex G-250) and reverse-phase liquid chromatography on Eurospher C18 column (250×4.6 mm), respectively. The results of this study have been recognized the high antioxidant activities of extracted hydrolysate from B. plicatilis and their feasibility of using them in food industries as a food complement
Levels of heavy metals in sediments in the vicinity of Chabahar Bay desalination plant
Desalination plants are potentially capable of having impacts on coastal marine environments due to the production of wastewater with high concentrations of salts (brine discharge) and some heavy metals. The aim of this study was to examine the concentration of accumulated metals (Ni, Cu, Cd, Fe, Zn, Pb) in the sediments near the brine discharge point in the Chabahar Bay. Twenty one sediment samples were collected from seven stations in summer pre-monsoon and post-winter monsoon, in April and October 2011. The results showed that stations closer to brine discharge points had higher concentrations of metals in the sediment than other stations. Metal contamination in sediment samples was below a critical level with the exception of cadmium with higher values than MAFF, ANZECC and FDEP standards at a maximum of 5.76 mg/kg dry weight. There was a clear decreasing gradient in heavy metal concentrations from station 2 to station 7, especially for Cd, Pb, Fe and Zn. The probable reason for this is the water circulation in the Chabahar Bay
Study of taxonomy and ecology of planktonic copepods of Poecilostomatida in Bahrakan waters (north western Persian Gulf)
The present investigation is based on separation and identification of Planktonic Poecilostomatoida in Bahrakan waters during July, August, October of 2010 and December, February, April of 2011. In this study The order of Poecilostomatida was represented by 3 species, Corycaeus andrewsi and Sapphirina nigromaculata andSaphirella- like copepodid. Abundance of each species was measured in sampling months. The highest density of Poecilostomatoid copepods were recorded in August and October 2010. C. andrewsiwith relative frequency of 73% was dominant species during the studying period among Poecilostomatoida and maximum abundance of it were observed in October 2010. Saphirella- like copepodid was observed in all sampling months. Maximum abundance of this species was in August and October 2010 and this report is the first report of this species in the Persian Gulf. There was Positive significant correlation coefficient between density of C. andrewsi and water salinity (P<0.05) but there was no significant correlation between the rest species and water parameters
Using of AMBI (azti marine biotic index) index to evaluation of khouzestan coastal sediment health status
Presence of each pollution and changing in the marine ecosystem have sever impacts on Biotic factors and economic ecological potential in this valuable area. Thus, ecological health monitoring to evaluation of habitat health are important.In this study, AMBI(Azti Marine Biology Index) was used to evaluation health of Bahrakan coastal area as a main fisheries and petroleum extraction ground. The results showed studied area classified in good ecological status. The dominance species was from Ophiuridae family with ecological group II. Based on richness and diversity index value, studied areas are classified in bad ecological status. This result discordantly can cause due to differences in influences variable. Low rate of water exchange, high degree of temperature and salinity maybe were lead to decreasing in macrobenthic richness and diversity index values but AMBI result that get from ratio between sensitive and resistant species, shows good ecological status
Effect of salinity and temperature changes from brine discharged of desalination plant on Polychaeta assemblage in Chabahar Bay
Desalination technology is growing due to population growth and water shortage. These kinds of activates can have environmental impacts where brine discharges into the sea. This study examined the effects of brine discharge from desalination plant Chabahar-Konarak on the sea environment were used to study polychata assemblage. Sediment samples were sampled from 7 stations in pre monsoon and post monsoon in year 2011 using by van veen grab (0/025m^2) samplers that 5 stations were around the discharge point and 2 station as controls. The results of the statistical analysis showed that the abundance and richness significances differences (P<0/05) between stations. The most abundance of polychaetes was occurred in station 6 with 3666.62 and 2079.92 individuals per m^2 in pre and post monsoon respectively. While the lowest values observed in station1 in pre and post monsoon periods with 306.97 and 0 numbers in m^2 .The richness, diversity and evenness results indicated that the highest and the lowest values is observed in control stations 0.94, 1.07 and 0/67 in pre monsoon and station 1, zero in post monsoon. According to results, we observed different sensitivity of polychaete to brine discharges because abundance and ecological indices were decreased in stations near the discharges area comparing to control stations far from the brine discharges zone. Results of the CCA indicated that salinity and temperature effects on polychaete structure. The most frequancy family in this study was spionidae that it showed tolerance of this family to brine discharges. With monsoon occurrence of stress added to the study area where that the lowest abundance (0) in one station in post monsoon
Study of morphology and density of Diogenes sp. (Anomura: Diogenidae) in Bahmanshir Estuary (NW Persian Gulf)
Taxonomic studies on the Anomura larvae of the Persian Gulf are relatively few. This research has been done on larval stage of Diogenes sp. (Anomura: Diogenidae) on coastal waters of Bahmanshir River. Anomura is a group of decapod crustaceans, including hermit crabsthat are cosmopolitan and could be found from coastal waters to 5000 m in depth. The larval stages differ among families of Anomura. Anomura larval samples collected by plankton net (mesh size of 300 µm) from seven stations in February 2011 to October 2012. Planktonic larval were sampled from the Bahmanshir River in north of the Persian Gulf. The larval stages illustrated and described in detail for Diogenes sp. Finally Diogenes sp. were identified and their schematic figures were made using Camera Lucida. Maximum value of the average abundance of larvae (12.3±3.4 ind.m^3) was recorded in May. Also positive relationship between salinity with frequency of Diogenes sp. were found significantly using spearman correlation coefficients (P<0.05)
A survey of discard fish in Khuzestan fishery grounds
The main purpose of this study was to describe and estimate the seasonal pattern of discard fish in the waters of the Persian Gulf coasts in Khuzestan. sampling was carried out Monthly by using fishing boats in the waters of Khuzestan province for one year in fishing areas of Lifeh, Boseif, Khure-mussa and Bahrakan.Discard fish samples were included 61 species from 37 families, nearly 39 percent commercial and 61 percent of non- commercial species. Rayfish and catfish have been observed in most fishing nets. Average size of most species particularly bony fish were under 15 cm. The amount of discard fish per unit of fishing effort is not significantly different between seasons. The highest portion of the catch belongs to Rayfishes. Total discard fishes of gillnets were estimated 3162 tones. Total weight of commercial fishes with small size in trash fish was estimated 225 tones. The rate and proportion of discard fish in total catch of gillnet was estimated 0.23 and 0.31 respectively. Chondrichthyes with 12 species and 60% of gillnet catch has the highest percentage of discard fish of gillnet. A large number of commercial species with small size such as Otolithes ruber (Schneider, 1801), Scomberomorus commerson (Lacepede, 1801) and Scomberoides commersonnianus (Lacepede, 1801) could be due to the role of nursery grounds in Khuzestan coastal waters
Spatial and temporal variability of brittle star (Macrophiothrix cheneyi: Ophiuroidea) in the shores of Chabahar Bay, Oman Sea
Echinoderm species are important members of benthic communities existing in subtropical to Polar Regions. They have an important role in nutrient cycles and other communications between organisms. This study investigated the distribution and abundance of brittle star Macrophiothrix cheneyi in the intertidal zone of Chabahar bay, the Oman Sea. Sampling was randomly done bimonthly using a square meter quadrate during one year, from November 2008 to September 2009, at 5 selected stations. According to the results of a Kruskal-Wallis analysis, the density of this species at different sampling times and stations revealed a significant difference (P<0/05). The highest frequency of this species was measured at the station of Chabahar University of Maritime and Marine Science in September 2008 (±1/54 3/58 ind.m^-2) and its lowest frequency was measured at Kolbe Qavasi station during the whole year except January. The difference in abundance (between the different months and stations) seems to be influenced by ecological (bed, food and shelter) and biological factors (fertility, hunting and competition). The investigation of distribution revealed that brittle stars in the intertidal zone under study followed random and patchy dispersion. The results of the stability indicator revealed that though the brittle star was rarely found during some periods, it was a common species in September 2008
Study of distribution and diversity of Polychaeta due to impact bottom trawling in Bahrakan fishing area (Persian Gulf)
The study took place to survey the changes in diversity and distribution of Polychaetes in fishing area of Bahrakan, due to the trawling. Sampling was taken before (15 May) of trawling and two weeks (5 Sep) and three months (14 Nov) after trawling in 2010, in three period in Bahrakan coast. Therefore, eighteen stations placed with the depth of 6 meters and 10 meters.The amount abundance Polychaetes had decreased significantlyin both depths two weeks after trawling (P0.05). Only in 10m depth, abundance Polychaetes after three months comparing to two weeks after trawling had increased significantly (p<0.05). Changing biomass Polychaetes was similar to Changing abundance. After the trawling, small size individuals became dominant.Abundance Species ofCossura longicirrattahad increased in both depths in two weeks after the trawling. Also in both depths, Shannon Diversity and Margalef Species Richness indices showedprocess decreasing and Simpson dominant Index showedprocess increasing. In both depths, Pielou Evenness Index two after trawling had increased. While, after three months comparing to two weeks after trawling had decreased and most effects of trawling were on 6m depth
Study of taxonomy and ecology of Planktonic Copepods of Poecilostomatida in Bahrakan waters (Northwestern Persian Gulf)
The present investigation is based on separation and identification of Planktonic Poecilostomatoida in Bahrakan waters during July, August, October of 2010 and December, February, April of 2011. In this study The order of Poecilostomatida was represented by 3 species, Corycaeus andrewsi and Sapphirina nigromaculata andSaphirella- like copepodid. Abundance of each species was measured in sampling months. The highest density of Poecilostomatoid copepods were recorded in August and October 2010. C. andrewsiwith relative frequency of 73% was dominant species during the studying period among Poecilostomatoida and maximum abundance of it were observed in October 2010. Saphirella- like copepodid was observed in all sampling months. Maximum abundance of this species was in August and October 2010 and this report is the first report of this species in the Persian Gulf. There was Positive significant correlation coefficient between density of C. andrewsi and water salinity (P<0.05) but there was no significant correlation between the rest species and water parameters