akram sadat naeemi

This study aimed to investigate the microplastic pollution in the sediments of the Sefidrud River. To achieve this goal, sediment samples were collected from five locations, including the river mouth, residential area, agricultural area, tourist area, and the wastewater inlet into the river. Three surface sediment samples and three deep sediment samples were collected from each station. The sediment samples were then analyzed to identify microplastics after separation using the Sediment-Microplastic Isolation (SMI) method and passed through a sieve. Stereomicroscopy was used to count microplastics' number, color, and size, while Raman spectroscopy and FESEM-EDS analysis were employed for polymer identification and elemental composition analysis. Among the 30 surface and deep sediment samples examined, 86 microplastic particles per 100 grams of dry sediment were identified. The wastewater station (27.90%) and the tourist area (24.41%) exhibited the highest microplastic pollution. Black color (37.20%), fiber shape (63.95%), and a size range of 0.5–1 millimeter (46.51%) were the most prevalent characteristics. Raman spectroscopy analysis of three random samples revealed that the polymer types were nylon, polyethylene, and polystyrene, while FESEM-EDS analysis showed that the microplastic particles had rough surfaces and contained elements such as iron, aluminum, and titanium in addition to the main plastic components like carbon and oxygen. These additional elements pose a significant threat to marine ecosystems. Given the concerning levels of pollution observed in the Sefidrud River, periodic monitoring of microplastics in water, sediments, and river organisms is essential. Furthermore, effective waste and wastewater management strategies are crucial, especially near river inlets. Above all, public awareness and education regarding microplastic pollution can play a significant role in its control.

The level of toxicity of contaminants undergoes changes in simultaneous exposure to other environmental pollutants and can cause different damages compared to their single exposure in aquatic animals. Therefore, this study aimed to quantitatively evaluate the uptake, elimination, and bioconcentration of zinc in exposure to zinc oxide nanoparticles in the presence and absence of silver nanoparticles in the gill, intestine, and liver tissues of zebrafish using toxicokinetic modeling. In the present study, 216 pieces of zebrafish (Danio rerio) were exposed to a non-lethal concentration of ZnO NPs (10 mg L-1), and two combined treatments of non-lethal concentrations of ZnO NPs and Ag NPs (10 mg L-1 of ZnO NPs + 0.02 or 0.04 mg L-1 of Ag NPs) along with the control were placed in three replications. After the completion of different sampling periods, the concentration of zinc metal in water and different tissues was measured. The results of this research showed that the concentration of zinc in the presence of Ag NPs was higher in gill > intestine > liver tissue, respectively. Also, the shortest half-life of zinc metal was observed in the gill tissue and the combined treatment of Ag NPs. The findings showed that in addition to the tissue, exposure time, and concentration, the presence of Ag NPs also affects the concentration of zinc metal.

In the present study, the interaction effect of climate change accomplished by phenanthrene as a representative of contaminants was investigated on the expression of nacrein gene in the mantle tissue of Pinctada radiata. To determine the studied gene expression pattern changes, pearl oysters were exposed to isolated/ combined warming in two levels (24 and 28 °C), acidification in two levels (8.1 and 7.6) and phenanthrene concentration in two levels (0 and 8 ng/L) for 4 weeks. Experimental setup was arranged in eight exposure treatments with triplicate aquaria per treatment and each aquaria containing 15 animals in 20 L. Sampling was performed three times, i.e.,24 h 48 h and 28 days after exposure. After 28 days of exposure, although no mortalities were observed in any treatments, the studied parameters caused significant reduction of nacrein expression in isolated exposure except for temperature, double interactions except for temperature and phenanthrene combination, and triple interaction. The quadruple interaction showed no significant effect on nacrein gene expression. These results demonstrated that the decreased seawater pH and elevated temperature in presence of contaminants caused downregulation of the nacrein gene and might impact the quality of pearl and shell of pearl oyster, P. radiata.

Marine animals are one of the most important sources of natural products with the origin of biological activities due to their secondary metabolites. These natural compounds can have many nutritional and medicinal uses. In recent years, efforts to find bioactive substances from organisms, especially marine animals, have increased. Echinoderms, including sea urchins (Echinoidea) and sea cucumbers (Holothuroidea) are an ancient and diverse group of marine invertebrates, which are a rich source of antibacterial and anticancer compounds with high activity mechanisms. Despite tremendous progress in medicine, diseases caused by microorganisms are still a major threat to public health. Nowadays, with the increase of antibiotic resistance and the growing of all types of cancers and the side effects of chemical drugs, the use of alternative and new natural treatments seems necessary. Recent research indicates that compounds isolated from different organs of sea cucumber and sea urchin can have antimicrobial and anticancer effects. In this narrative review, the findings of the antimicrobial and anticancer effects of sea cucumber and sea urchin from the Persian Gulf and Oman Sea in the last decade were investigated.

The increase in population and the development of various industries have caused a large number of pollutants to enter the water environment. One of the major environmental pollutants is heavy metals. Due to characteristics such as chemical stability, poor degradability, and the power of bioaccumulation at different levels of the food chain, these metals cause harm and ecological risks to living organisms. Every year, toxic and chemical effluents enter rivers, seas, and oceans during agricultural and industrial activities without observing environmental considerations, which has caused water, sediments, and aquatic pollution and created many problems for the environment and humans. Regarding the pollution of heavy metals in the water and sediments of the Persian Gulf, many studies have been conducted, some of which indicate the presence of pollution in the water and sediments. In the present study, a comprehensive review of the studies conducted regarding heavy metal pollution in water and sediments of Persian Gulf coasts has been done.

Staphylococcus aureus and Pseudomonas aeruginosa are important human bacterial pathogens, which are resistant to several antibiotics. One of the main causes of their resistance is the ability of biofilm formation.

The present study aimed to evaluate the antibacterial and antibiofilm activity of the extracts of Vibrio parahaemolyticus, V. alginolyticus, Pseudoalteromonas gelatinilytica, and Pseudoalteromonas piscicida isolated from sea anemone (Stichodactyla haddoni) against S. aureus and P. aeruginosa.

Four isolated bacteria were identified using biochemical and molecular identification methods, and their extracts were obtained by mixing the cell-free supernatants from their old broth culture using ethyl acetate and methanol as the solvents. The agar well-diffusion and micro-dilution methods were also applied to determine the antibacterial activity, minimum bactericidal concentration (MBC), and minimum inhibitory concentration (MIC) of the extracts. The ability of the extracts to inhibit biofilm formation and disrupt the preformed biofilm of the pathogens was attained through crystal violet staining in 96-well microtiter plates. To determine the nature of the extracts, they were exposed to protease enzyme, and the antibiofilm activity was compared with the untreated extracts.

The extracts of the four isolated bacteria inhibited bacterial growth and biofilm formation and disrupted the preformed biofilm of S. aureus (MIC = BIC = 600 g/mL) and P. aeruginosa (MIC = BIC = 300 g/mL). In addition, the active compounds of the extracts with antibiofilm activities were mainly proteases.

According to the results, V. parahaemolyticus, V. alginolyticus, P. gelatinilytica, and P. piscicida had antibacterial and antibiofilm potential against S. aureus and P. aeruginosa, and their extract could also be further analyzed as an alternative to antibiotics.

Aeromonas hydrophila is one of the most important aquatic pathogens that cause fish losses and poor product quality in fish farms. The ability of Aeromonas hydrophila to form a biofilm makes this bacterium resistant to antibiotics. Hence, finding new antimicrobials with the potential to inhibit biofilm formation would be valuable. The aim of the present study was to evaluate the antibacterial and antibiofilm activity of the extract from Pseudoalteromonas piscicida, isolated from the sea anemone (Stichodactyla haddoni) against Aeromonas hydrophila. The Microdilution broth method was used to determine the minimum bactericidal concentration (MBC), and minimum inhibitory concentration (MIC) of Pseudoalteromonas piscicida extract. The anti-biofilm ability of this extract against formation of Aeromonas hydrophila biofilm was assessed using crystal violet staining method in 96-well plates. The results showed that the extract of Pseudoalteromonas piscicida inhibited the growth and biofilm formation of Aeromonas hydrophila at MIC=MBIC= 200 mg/ml. In addition, using physical and chemical treatments, it was shown that the active compounds are mainly proteinous in nature and are proteases. The results from the experimental challenge of zebrafish (Danio rerio) with the pathogen demonstrated that oral administration of Pseudoalteromonas piscicida extract in two safe doses of 200 and 400 mg mL-1 increased survival rates of the fish and decreased colonization of Aeromonas hydrophila in their intestine within 7 days. The results of the present study showed that Pseudoaltromonas picisidia extract contains bioactive compounds with antibacterial and antibiofilm ability against Aeromonas hydrophila and due to its low toxicity in fish, if purified, it can be a good alternative to antibiotics.

Nowadays one of the aquatic environment problems is the entry of industrial wastewater containing nanoparticles. In the present study, the effects of copper oxide nanoparticles (CuO NPs) on some enzymes and histological alterations of liver and kidney tissues in the juvenile carp was assessed. At first, acute toxicity (LC50 96h) of CuO NPs were determined. Then, juvenile carps were exposed to the sublethal concentrations of 50, 100 and 200 mg/l of CuO NPs for 96h. Liver and kidney tissues of carp were separated after four periods. Also, ALT, AST, ALP and LDH enzyme activity assay in tissue extracts was done. The analysis of all enzymes activity in liver at a concentration of 200 mg/l after 96h, showed significant increase compared to the control treatment (P<0/05). In kidney, ALP and LDH enzyme activity for all of the four periods at concentration of 200 mg/l and GOT and GPT enzyme activity after 48, 72 and 96h at concentration of 100 and 200 mg/l showed significant difference. In the acute treatments of liver tissue side effects such as blood congestion, cellular necrosis, and cell atrophy and fatty degeneration was observed. kidney tissue were indicated same histopathological changes and shrinkage or degeneration of Bowman's capsule, glomerular expansion, hemosiderin deposits, tubular necrosis and degeneration or occlusion of the tubular lumen. The results showed that sublethal amounts of CuO NPs could affect the activity of the liver and kidney enzymes of the common carp and showed significant histopathological effects.

The aim of the present study is to compare the effects of titanium dioxide in nano scale and bulk form in gill, liver and intestine tissues of zebrafish (Danio rerio). In this study About 150 zebrafish exposed to static-renewal condition of TiO2 particles treatment. These nanoparticles and bulk titanium dioxide in concentrations of 1 and 10 mg.l-1 and a blank group in three replicate for 30 days. After the period of treatment (30 days) the fishes were stabilized in formalin and stained for further classic Histological studies. The results indicated that TiO2 in nanoscale and bulk forms can result in   epithelium separation, edema, hyperplasia, adhesion in lamella and Hyperemia, hypertrophy in filament of zebrafish (Danio rerio).  Also  abnormalities as cytoplasmic vacuolization, increase of melanomacrophage centers,  congestion and hepatocyte degeneration were observed in liver and injuries such as epithelium separation, increased and inflammation of goblet cells, necrosis and hyperemia in intestine tissue of zebrafish. The findings also suggested that nanoparticles induced more severe abnormalities in comparison with their bulk counterparts. Also, most of the mentioned abnormalities are dependent to the materials concentration. So, the severity of abnormalities was highest at 10 mg.l-1 concentration of the titanium dioxide nanoparticles compared with other treatments.

Since nanoparticles cause increase of serious threat to human, animals and aquatic ecosystems, toxicity of copper oxide nanoparticles (CuO-NPs) on cyanobacteria Anabaena sp. in different concentrations were studied using growth inhibition test (OECD201). The negative Zander cyanobacteria were grown in the culture medium (Z-8-N) under optimum conditions of light, temperature and aeration in growth chamber. After starting the logarithmic growth phase, samples were exposed to various concentrations of copper oxide nanoparticles at intervals of 24, 48 and 72 hours. The number of cyanobacterial cells was daily counted and analyzed based on Probit analysis. The effective concentration (EC50), no effect concentration (NOEC), specific growth rate (μ), doubling time (G), percentage growth inhibition (I%) and chlorophyll content was calculated. Treatments and control were significantly different in terms of cell density and growth inhibition percentage at specific intervals. In addition, the chlorophyll content of different treatments showed significant difference compared to control. It seems reducing the efficiency of photosynthesis is one of the routes that lead to considerable damage of copper oxide nanoparticles on Anabaena sp.

Over the past years, silver nanoparticles (AgNPs) due to their anti-angiogenesis, anti-bacterial, and anti-cancer activity have attracted researchers’ interests. The aim of this study was to evaluate the cytotoxicity effects of biosynthesized AgNP using red macroalgae Laurencia caspica on human breast cancer (T47D) cells.
In this experimental study, the biosynthesis of AgNPs was evaluated, using Laurencia caspica.The characterization of developed AgNPs was performed through ultraviolet-visible (UV-vis) spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The T47D and MRC-5 cell lines were treated with various concentrations of fabricated AgNPs for 24 and 48 hours, rspectively. The viability effects of cells and half maximal inhibitory concentration) IC50 (were evaluated by MTT assay.
Findings: The fabricated AgNPs were monitoring characteristic surface Plasmon resonance peak at around 420nm. The SEM and TEM results for size and morphological studies of AgNPs showed that nanoparticles were of spherical shape ranging from 10 to 50 mm. The MTT results demonstrated that AgNPs significantly decreased the viability of cells in dose-and time-dependent manners. The IC50 value of nanoparticles for T47D and MRC-5 cell lines were calculated as 29.37 mg/mL and 42.13 mg/mL 48 hours following treatment with nanoparticles, respectively.
Discussion & Based on the current study, the biosynthesized AgNPs can cause more cytotoxic effects on breast cancer cells compared to the normal cells. Thus, they can be considered a promising procedure for the treatment of breast cancer.

Lead as a contaminant of the environment cause cell poisoning. The unicellular green algae Chlorella Vulgaris belongs to the family Chlorellaceae. Since C.Vulgaris has a simple cell structure and unique feature, it is used as a model in plant physiological studies. In order to investigate the growth and adaption of Chlorella sp. to different concentrations of lead (0,10 ,50 , 80 mgL-1) , an experiment was done in the medium Zn With 3 replication in the growth chamber with 12 h light photoperiod, temperature of 25 ± 2 °C, light intensity of 2500 lux and with proper aeration, during 18 days. Growth curve of total samples were determined by measuring the absorbance of 750 nm. Growth rate, chlorophylls and malondialdehyde content and sorption of lead by the algae were measured. Results showed that by increasing concentrations of Lead in the medium up to 80 mgL-1, biomass production, photosynthetic pigments and subsequent growth rate were decreased and samples in less time were able to enter stationary phase and the amount of malondialdehyde (MAD) in treatment of 50 and 80 mgL-1 were significantly increased compared to control. Generally, high concentrations of toxic metal lead influenced the majority of physiological and vital parameters of C.Vulgaris but as a resistant microalgae, despite of the reduction in cell division still retained its growth potential.

The increase of copper oxide nanoparticle (CuO-NP) utilization in industry during recent years has resulted in their entry into aquatic ecosystems. In light of this fact, we have studied the toxicity of CuO-NPs at various concentrations on Chlorella vulgaris using an algal growth inhibition test (OECD201). Chlorella vulgaris was grown in positive Zander (Z-8 + N) media in a growth chamber. After reaching to the logarithmic growth phase, the algae were exposed to various concentrations of CuO-NPs at intervals of 24, 48 and 72 hours. Algal cell numbers were counted daily and the data were analyzed by Probit analysis. Some parameters such as: the effective concentration (EC10, EC50, EC90), no observed effect concentration (NOEC), specific growth rate (μ), doubling time (G) and percentage growth inhibition (I %) were calculated. The values of EC10 = 12.588, EC50 = 43.699, EC90 = 152.019 and NOEC = 4.3699 mg/L were obtained after 72 hours. The results showed significant differences between control and treatments at specified intervals of cell density and percentage of growth inhibition (P <0.05). In addition, chlorophyll and carotenoid content in treated cells were significantly lower compared to those in control samples; a decrease in the efficiency of photosynthesis is very probably a major mechanism in the reduced growth and viability of C. vulgaris exposed to CuO-NPs.

Effects of ultraviolet (UV) radiation on biological matter became an important issue over the past three decades since the first reports of man-made changes in stratospheric ozone layer, which covers and protects the earth’s surface from harmful ultraviolet radiation. The aim of this study was to evaluate and compare the effects of different intensities of UV radiation on the physiological indices of microalgaes Chlorella sp. and Anabaena sp. After preparation of pure samples Anabaena sp. and Chlorella sp. were transferred to flasks containing the appropriate medium and then exposed to UV-C radiation at various time intervals (1, 3, 6 and 12 h) with three replicates. The treated and control samples were placed to growth chamber in favorable conditions of temperature 25±2°C, with light intensity of 2500 lux and light period of 12 hours light and 12 hours darkness in aerated condition for 12 days. The results showed that by increasing the intensity of UV-C radiation up to 12 hours factors like the growth, growth rate, content of photosynthetic pigments and total protein content based on dry weight was significantly reduced when compared to control. Also, in both microalgae, Malondialdehyde (MDA) content was increased in comparison with control group. Furthermore, comparison of the two microalgae revealed that, Anabaena sp. showed more reduction in examined parameters which indicated that the Anabaena sp. is a more sensitive species.

One of the most effective technology to remove heavy metals is using of bio-absorbent. In the present study modeling, kinetics and isotherm of lead sorption by the unicellular green algae Chlorella vulgaris from aqueous solutions was assessed. After culturing algae in Z medium and reaching the logarithmic phase, it was harvested and centrifuged, then dried by freeze dryer. Afterward, through the evaluation of parameters affecting the biological absorption, the isotherms and adsorption kinetics of the metal were calculated and determined. Results indicated that with increasing of adsorbent amount, adsorption was decreased. Also, after increasing of the initial concentration of metallic ion, metal removal rate was reduced. Furthermore, absorb kinetic studies showed that the biosorption of lead by C. vulgaris following second-order kinetics and adsorption isotherm is well fitted to the Langmuir model. Also, modeling heavy metal removal using multivariate linear regression indicated that the biosorption process and the effect of parameters on it can be described by a quadratic equation. This equation revealed that pH is the most effective parameter on metal removal by C. vulgaris.

Microalgae lipid is used as a feedstock for biodiesel production. Lipid content is correlated with the microalgae species and growth conditions. In this study, variations in total lipid content in the green microalgae of Chlorella sp. under nitrogen starvation stress after 4, 8 and 12 days was examined. Microalgae were cultured in the Zinder-8 medium. When they reached the semi-logarithmic growth phase, biomass was harvested and transferred to Zinder-8-N medium. The total lipid content was calculated after extraction with a solution of chloroform/methanol (2:1). Triacylglycerol which is used in biodiesel production separated qualitatively using thin layer chromatography. The results showed that the total lipid content under stress condition after 4, 8 and 12 days increased significantly compared to control (P≤0.05), in average 23.46% more than the control. Also, according to the result of thin layer chromatography, triacylglycerol concentration increased in the microalgae under the stress. In general, nitrogen starvation stress led to increased total lipid content in the green microalgae of Chlorella sp.

Because of the similarities in appearance between species of Oligochaeta, identify, characterize and differentiate them from each other to determine the population dynamics or molecular and phylogenies studies seems necessary. The aim of this study is to provide an identification key and diagnostic methods for the two species of genus Limnodrilus in the Anzali Wetland. In compare key features to identify and separate the two species was found in L. hoffmeisteri genital sheath is shorter and thicker than Limnodrilus claparedianus. Statistical analysis showed that this is a significant difference between the two species (P