CYP1A gene plays a critical role in main involved enzymes in the xenobiotic metabolism. We conducted an experiment to evaluate the CYP1A gene expression in normal or in benzo(a)pyrene (BaP) exposure condition. Healthy mudskippers (Boleophthalmus dussumieri), were sampled from Shif shores in Boushehr city, IRAN. Then we measured the mRNA expression of CYP1A gene in different tissues by RT-PCR method. RT-PCR analysis revealed that liver organ had the maximum gene expression and in kidney, gill, heart, brain, and intestine tissue showed different CYP1A gene expression from 49, 46, 40, 35, 11, and 10% in normal condition respectively. To study the physiological responses of organs, 25 μg/g Bw of Bap was administered to the fish and CYP1A gene expression changes were followed to 24 h after injection. The results showed that CYP1A gene expression were increased extremely and reached 84.4 and 83.2 fold higher than normal condition in kidney and liver respectively. According to the results, liver organ showed the highest response of CYP1A gene expression like other fish species. But, CYP1A gene expression in other organs was higher in comparison with liver organ. The basal expression pattern of genes depends on the species. High level of CYP1A gene expression in this study is due to PAH exposure of mudskipper in natural conditions. In total, the basic expression of the CYP1A gene depends on the species and the ecological conditions of the species. The results showed that the liver was main organ, and other organs (kidneys, intestines, and gills) play an important role in xenobiotic metabolism. The results showed that most changes in gene expression occur in kidney, intestine and gill, so CYP1A gene expression changes in in these tissues could be used as a biomarker.
The marine environment is a rich source of biodiversity and chemical compounds, and based on biodiversity knowledge, it is believed that the highest biodiversity is related to living organisms in tropical and semiequatorial regions. The goal of this study was the biodiversity of Demospongiae sponge in Assaluyeh area in May 2018. Sampling carried oyu by using Coadrat in three sites with three replicat in summer season. After sampling and solution of samples, identified Sponges with spicouls. According to this study, seven species from five genous Demospongiae sponge identified by using spicouls. Identified sponges were Chondrilla australiensis, Chondrilla nucula, Haliclona caerulea, Haliclona toxia, Clionaopsis platei, Ircinia sp and Iotrochota sp.
Marine actinobacteria are the prolific sources of marine natural products. The aims of the present study were to propose a process for selective isolation of actinobacteria from the two species of sea cucumbers Holothuria scabra and Holothuria leucospilota and also to find isolates that produce antioxidant and cytotoxic metabolites. We collected 2 sea cucumbers species from the Larak Island, Persian Gulf using scuba diving. The selective isolation process was performed by 3 culture media and 7 physical and chemical treatments. Antioxidant activity of extracted metabolites were evaluated using DPPH radical scavenging activity. Evaluation of cytotoxicity of the extracted metabolites was carry out using brine-shrimp microwell cytotoxicity assay. Out of 53 actinobacterial isolates, 58.49% was isolated from sea cucumber H. leucospilota. Starch casein nitrate agar medium and heat treatment isolated 22 and 21 actinobacterial isolates of and exhibited maximum efficiency in selective isolation of actinobacteria. Approximately, 37.03 % of the extracted metabolites scavenged DPPH radicals at IC50 ranges from 136.1 to 641.5 μg/ml. While, 33.33 % of the extracted metabolites showed cytotoxic activity against artemia cells at LC50 range from 118.12 to 653.15 μg/ml. These results represented a selective isolation process for sea cucumber associatedactinobacteria and also could provide an evidence that confirms the active association of the actinobacteria with the two species of the Persian Gulf sea cucumber species. The isolated strains could be a potential source for finding pharmaceutical natural products.
The present research was carried out with the aim of measuring the levels of the heavy metals Cu, Zn and Fe in the muscle tissues of the Acanthopagrus cuvieri in Bushehr port. To this end, 30 A. cuvieri with an average of 840.73±156.101 gr and 34.28±3.089 cm were hunted in spring 2018. The samples were washed with distilled water and a portion of the pure muscle tissues was isolated. After dehydrating the tissues and discharging the water in the intertextual space, 0.5 gr of the powdered tissue sample was isolated and the acid digestion of the samples was carried out using 5 ml of concentrated nitric acid. To measure the levels of the heavy metals Cu, Zn and Fe a (Perkin Elmer 3030) atomic absorption spectrophotometer was employed. The results of measuring the concentrations of the heavy metals Cu, Zn and Fe in the muscle tissues of the A. cuvieri suggested that the mean and standard deviation were (6.32±0.22, 61.12±0.14 and 4.86±0.36) mg/kg dry weight during spring, respectively. The results of this study revealed that the Cu and Zn concentration in muscle tissues of A. cuvieri in study station were lower than the levels permitted within the standards of World Health Organization (WHO), Food and Agricultural Organization (FAO), National Health and Medical Research Council (Australia) (NHMRC), Ministry of Agriculture and Forestry and Fisheries UK (MAFF). But Fe concentration in muscle tissues of Acanthopagrus cuvieri in study station was higher than the level permitted within the standard of Food and Drug Administration (FDA). Hence, these two species will not pose severe general health risks to human consumers.
Sea cucumbers can mitigate some impacts of climate change through digestion of benthic sands and production of calcium carbonate. The projected ecological benefits of sea cucumbers in warmer, more acidic oceans are contingent on the capacities of individuals to acclimate and populations to adapt to climatic changes. The goal of this experiment was to evaluate the degree to which warming waters would impact three abundant species of sea cucumbers on the Heron Reef in Queensland, Australia. We conducted a behavioral assay using three species of sea cucumbers, Holothuria atra, Stichopus chloronotus, and Holothuria edulis. Individuals from each species were subjected to three conditions mimicking current summer temperatures, current winter temperatures, and an elevated temperature consistent with future ocean warming by the year 2100. Sea cucumber reactions were evaluated using righting time as a proxy for their stress levels and overall tolerance of warming events. The three sea cucumber species reacted differently to water temperature changes: H. atra’s righting times declined with temperature, S. chloronotus had greater righting times at high and low temperature extremes, and H. edulis’s righting times remained relatively constant throughout. Our results suggest that each of these species might respond differently to ocean warming and while some may be able to continue to combat climate change in benthic communities, others may decline in ecological function.
The genusCentrodiniumcontains oceanic and predominantly tropical species that have received little attention. Three species ofCentrodiniumwere examined using thecal plate dissociation, scanning electron microscopy, and molecular sequences. The apical horn ofCentrodinium intermediumandC. eminensis formed by the elongation of the fourth apical plate, and a second apical split into two plates. InC. punctatumtwo apical plates (2′ and 4′) almost completely encircle the apical pore plate (Po), while the contact with the plate 1′ in the ventral side is much reduced, and the plate 3′ does not reach the Po. Moreover, its left posterior lateral sulcal plate is longer than its right pair, while reversed in the typicalCentrodiniumspp. The sulcal posterior plate ofC. punctatumis located in the left-ventral side below the plates 1′′′ and 2′′′, while the sulcal posterior plate located in the right face below the plates 4′′′ and 5′′′ in the typicalCentrodiniumspp. Phylogenetic analyses based on the small and large subunit of the rRNA gene showed thatCentrodiniumspp. andAlexandrium affine/A. gaarderaeclustered as a sister clade of theAlexandrium tamarense/catenella/fraterculusgroups. The clade of the subgenusGessnerium, and the clade of the type species ofAlexandrium,A. minutum, with four divergent species, clustered in more basal positions. The polyphyly ofAlexandriumis solved with the split into four genera: (1)Alexandriumsensu stricto for the species of the clade ofA. minutumand four divergent species; (2) the reinstatement of the genusGessneriumfor the species of the clade ofA. monilatum; (3) the reinstatement of genusProtogonyaulaxfor the species of thetamarense/catenella/fraterculusgroups, and (4) the new genusEpisemicolongen. nov. forA. affineandA. gaarderae.New combinations in the generaGessnerium,Protogonyaulax,andEpisemicolonare proposed.
This research was carried out to assess the amount of the biomass and Catch Per Unit of Area (CPUA) and also to determine the distribution pattern of the haemulidae family in the northern parts equipped with trawl floor area cape of meydani ('58 ̊55) east To Govater (61°25׳) east in the waters of the Oman Sea (Sistan and Baluchistan province) based on trawl survey results in 2013 by R/V Ferdows-1. The area divided to the 5 regions (A, B, C, D, E), with deep layer of 10-20 meters, 20-30 meters, 30-50 meters and 50-100 meters at a total 82 stations, were determined. Required information such as geographic location, depth, covered distance and silence were recorded. The fish caught after being unloaded on the deck were separated from the family and then counted and weighed and calculation of catch per unit area and live mass was performed.The highest biomass and CPUA of haemulidae was recorded approximately 439.2 tons and 1213.8 kg/nm in the stratum B and for depth layer of 30-50 m with value of 455.9 kg/nm and the highest biomass for depth layer of 50-100 m with value of 405.2 tones. Finally depth distribution chart and distribution map was drawn with ArcviewGIS software. The findings can be concluded that best region for hunting and main habitat for Haemulidae are B stratum and Preferential depth layer is 50-100 m,that Due to different biological and non-organic factors as hunting, temperature, salinity and type of bed.
Hypnea bryoides collected from the Arabian Sea on the southern coast of Oman was investigated for κ-carrageenan optimal extraction conditions. The effects of different conditions of alkali treatment (4, 6, and 8% w/v NaOH), temperatures (70, 75, and 80°C), and time (2, 2.75, 3.5 hours) on carrageenan yield and chemical and thermal properties were evaluated. Yield was significantly affected by alkaline concentration and temperature, with highest value of 26.74 ± 5.01%. Molecular weights of the extracted carrageenan were significantly reduced by increased temperatures and ranged from 5.95 ± 0.49 × 105 Da to 13.90 ± 0.14 × 105. FTIR showed that samples under all extraction conditions were similar and confirmed the presence of κ-carrageenan with no traces of μ-precursor. Sulfate content was also significantly reduced by alkaline concentration (from 4% to 6%) and ranged from 7.62 ± 5.52% to 17.02 ± 0.14. Thermal properties showed more sensitivity towards temperature and alkaline strength parameter than time. In addition, melting and gelling temperatures were significantly correlated with the molecular weight, but not sulfate content. In conclusion, mild extraction conditions were found to be more efficient in introducing the intended structural modification while getting the highest yield and quality.
The main objective of the present study was to investigate the changes in length, weight, condition factor (CF) and relative condition factor (Krel) of Rutilus kutum in different seasons and depths in the eastern coasts of the Caspian Sea (Goharbaran region In this study, three fishing methods, including small mesh size beach seine, gillnet and commercial beach seine were used during January 2014 to July 2014. The results showed that the slope (b value) of the length-weight relation was 3.0003 which was not significantly different from 3 methods (P>0.05), indicating isometric growth. Small and large fish were caught in small mesh size beach seine and commercial beach seine, respectively. The average length and weight were significantly different among three fishing methods (P<0.001). The average (±SD) CF of small mesh size beach seine, gillnet and commercial beach seine were calculated as 1.30±0.20, 1.38±0.17, 1.29±0.13 and the Krel were recorded as 1.30±0.19, 1.37±0.17 and 1.29±0.13, respectively. For both variables, there were significant differences among three fishing methods (P<0.05). Also, the averages for CF and Krel were significantly different among the different length classes and seasons (P<0.001). Based on the average Krel, it can be concluded that Rutilus kutum had a good feeding and growth conditions in the Goharabaran region.
In the exploration of the hydrothermal system of the Guaymas Basin (GB) between 27° 00′ 35′′ and 27° 00′ 50′′ N and 111° 24′ 15′′ and 111° 24′ 40′′ W in the Gulf of California, carried out on the R/V Atlantis and of the DSRV/Alvin in October 2008, four cores of surface sediments were obtained to analyse photosynthetic pigments at two locations with contrasting extreme conditions: Oil Town and Great Pagoda. We identified nine pigments: Chlorophyll-a, Phaeophytin-a, Phaeophorbide-a, Pyropheophytin-a (degradation Chlorophyll-a products), β-Carotene, Alloxanthin, Zeaxanthin, Diadinoxanthin, and Prasinoxanthin (carotenoids). The maximum pigment concentration was registered in the Great Pagoda (10,309 ng/g) and the minimum in Oil Town (918 ng/g). It is demonstrated that photosynthetic pigment profiles in surface sediments depend on the heterogeneity of the extreme conditions of each site caused mainly by temperature and bacterial substrates. Therefore, there were significant differences (p <0.05) in the pigmentary profile of the four sedimentary cores analyzed. However, no statistical differences (p > 0.05) in the concentration of pigments have been detected. We conclude that the photosynthetic pigments contained in the surface sediments of the hydrothermal vents in the Guaymas Basin are primarily of chemoautotrophic bacterial origin.
The trends of the world’s top ten countries relating to shark bite rates, defined as the ratio of the annual number of shark bites of a country and its resident human population, were analyzed for the period 2000-2016. A nonparametric permutation-based methodology was used to determine whether the slope of the regression line of a country remained constant over time or whether so-called joinpoints, a core feature of the statistical software Joinpoint , occurred, at which the slope changes and a better fit could be obtained by applying a straight-line model. More than 90% of all shark bite incidents occurred along the US, Australia, South Africa, and New Zealand coasts. Since three of these coasts showed a negative trend when transformed into bite rates, the overall global trend is decreasing. Potential reasons for this decrease in shark bite rates—besides an increase in the world’s human population, resulting in more beach going people, and a decrease of sharks due to overfishing—are discussed.
The concept of “sustainability” has become the current answer to absolving the world of its environmental and economic crises in the 21st century. This paper analyses seven socioeconomic factors (age of household head, household average annual income, marital status of household head, gender of household head, household size, education level of household head, and period of residence of household head) influencing extreme degradation of seagrass and exploitation of mangrove resources in Zanzibar, Tanzania. To accomplish this, Participatory Rural Appraisal approaches and household questionnaire survey were used to obtain information on primary data. Multiple regression analysis and descriptive statistics were used to analyze quantitative data while content analysis was used to analyse qualitative data. The findings revealed that all the socioeconomic variables tested were statistically significant (P<0.05) and had an influence on the exploitation of mangrove and degradation of seagrass except gender of the household (P=0.88) and household annual average income (P=0.655), respectively. In addition, statistical analysis revealed that there was significant difference in the mangrove status between the sites (p= 0.0001, χ2 =27.27) with more exploitation at Charawe compared to Kibele village, whereas no significant differences were revealed in the status of seagrass between the two sites (p= 0.2693, χ2 =1.2202). On one hand, the findings revealed that at Kibele and Charawe 60% and 50% practice gleaning, 40% and 55% are engaged in seaweed farming, and 60% and 70% collect bait from seagrass meadows, respectively. All these activities had direct influence on seagrass status. On the other hand, the finding revealed that livelihood needs, population growth, level of education, and lack of alternative source of income are the key drivers to exploitation of coastal natural resources especially mangrove and seagrasses. To ensure sustainable exploitation of coastal resources alternative livelihood activities such as farmed fish, small/petty business, and agriculture activities that are profitable and easy to manage should be introduced to the local coastal community to enhance active participation in conserving resources and improving their livelihood.
Species of the genus Ulva are common in anthropogenically disturbed areas and have been reported as the cause of green tides in many areas of the world. In addition, they rank among the main marine groups used in a wide range of commercial applications. By displaying few distinctive morphological characters, some taxonomical identifications are difficult and the genus is under a conundrum. Our aims were to provide ecophysiological information about three Ulva species in response to abiotic factors and to evaluate the proposal of ecophysiological information and the chlorophyll-a fluorescence technique as auxiliary tool to resolve the long-standing taxonomic confusion. We hypothesize that three cooccurring specimens (U. fasciata Delile, U. lactuca Linnaeus, and U. rigida C. Agardh) have different ecophysiological responses (as measured by the effective quantum yield of photosystem II by pulse amplitude modulated fluorometers) under manipulated conditions of temperature and nutrient concentration. Ulva lactuca and U. rigida showed different photosynthetic efficiencies related to temperature, whereas no difference was recorded for U. fasciata individuals. These results provide a reasonable explanation for the variability in spatial and temporal abundance of these species of Ulva on rocky shores. We proposed the use of ecophysiological information by chlorophyll-a fluorescence as an auxiliary tool to corroborate the taxonomic distinction of Ulva species. We reinforce the statement of U. fasciata and U. lactuca as distinct valid species.
Marine organisms are exposed to a pH decrease and to alteration of carbonate chemistry due to ocean acidification (OA) that can represent a source of oxidative stress which can significantly affect their antioxidant defence systems efficiency. The polychaetes Platynereis dumerilii and P. massiliensis (Nereididae) are key species of the benthic community to investigate the effect of OA due to their physiological and ecological characteristics that enable them to persist even in naturally acidified CO2 vent systems. Previous studies have documented the ability of these species to adapt to OA after short- and long-term translocation experiments, but no one has ever evaluated the basal antioxidant system efficiency comparing populations permanently living in habitat characterized by different pH conditions (acidified vs. control). Here, individuals of both Platynereis species, sampled from a natural CO2 vent system and from a nonventing “control” site in three different periods (April 2016, October 2016, and February 2017), were compared highlighting signals which suggested the ability of both species to acclimatize to high pCO2–low pH with slight seasonal variations of their antioxidant efficiency and the absence of disturbances of the oxidative status of Platynereis spp. tissues.
The circumglobal deep-sea gelatinous giant octopod, Haliphron atlanticus, reaches 4 m in length and uses both benthic and pelagic habitats in the upper 3000 m of the ocean during different life history stages, but it is rarely observed due to the deep-depths where it typically lives. It has been collected in trawls and observed a few times near continental margins or islands and has been identified in the stomach contents of deep-diving predators such as sperm whales and blue sharks or detected as body fragments after predation events. An individual H. atlanticus (~1 m in total length) was video-recorded at 12:21 for about 3 minutes in front of the Shinkai 6500 submersible at 586–599 m (6.5°C, salinity 34.4) along the West Mariana Ridge. It made no escape attempt as the submersible approached and it moved slowly up or down in front of the submersible. It was over the outer seamount-slope (bottom depth ~3208 m) ~50 km west of seamounts (≥1529 m summits), but how it fits into the mesopelagic food web along the ridge is unclear. More information is needed to understand the role of H. atlanticus in oceanic food webs and if it typically lives along seamount ridges.
