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Aim: The purpose of this study was to investigate the effect of replacement of copper sulfate with nano oxidase in diet on growth and survival, enzymatic activity and pathology of liver tissue of goldfish in 2018. Material and Methods: Experimental treatments consisted of 5 control treatments, 3 mg / kg copper sulfate; 3 mg / kg nano-oxide, 5 mg / kg nano-oxide and 10 mg / kg nano-oxide, and fish were given 4% by weight twice a day for 60 days. The body was fed manually. At the end of the trial period, growth and survival indices , liver enzymes activity (alkaline phosphatase, aspartate transaminase, alanine, Aminotransferase) as well as liver tissue pathology were evaluated. Finding: Based on the results, using copper nanoparticles at different levels of 3, 5 and 10 mg / kg diet instead of copper sulfate in the diet can improve the growth performance and survival of goldfish. Copper sulfate also has more negative effects on liver tissue than nanoparticles, as well as alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase enzymes; therefore, the replacement of copper sulfate with copper nanoparticles in the diet seems to reduce the effects of water. On the other hand, histopathological results of liver tissue treatment with 5 and 10 mg Cu / kg diet showed that Cu nanoparticles cause tissue lesions and deleterious effects (albeit less than copper sulfate). Conclusion: Copper sulfate with copper nanoparticles at levels of 3 mg / kg diet To be carried out.

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Astaxanthin is a precious material and has many favorites for human; it is extracted from some creatures such as Haematococcus lacustris. Researchers try to maximize the production of this material. In this research effects of linoleic acid (LA), TiO2 and SiO2 Nanoparticles (NPs) were investigated on astaxanthin production, and expression of two astaxanthin metabolic pathway genes (CRTO and CRTR). The microalgae was cultured in BBM medium for 19 days autographically. In 3rd day, treatments were added to the cultures and astaxanthin measured in 3 days respectively in logarithmic and stationary phases, also RNA was extracted, Real-time PCR applied and Gene expression investigated in 11th. 30 µM LA and TiO2 NPs (40 mg L-1) induced 3.4 and 1.5 times astaxanthin production compared to the control, furthermore, CRTO and CRTR under 30 µM LA and SiO2 NPs (40 mg L-1) treatments displayed the highest gene expression. It was demonstrated that special concentration of Linoleic acid and TiO2 NPs, as inducers, could be used for astaxanthin production; also, Linoleic acid has a direct relationship with astaxanthin production and CRTO´s gene expression in the microalgae.

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Steroids are one of the most important and abundant secondary metabolites of marine sponges. The aim of this study was to investigate the antibacterial properties of steroidal fractions derived from the Persian Gulf sponge Axinella sinoxea. Extraction was first done by Acetone and then the fractions were separated through column chromatography with silica gel. Identification of steroidal fractions were done by thin layer chromatography (TLC) and gas chromatography coupled with mass spectrometry (GC–MS). Then, antibacterial properties of steroids were identified and minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) were investigated by tubular dilution. Two types of steroids including Stigmasta-5,24(28)-dien-3-ol,(3β-24Z) and Ergosta-5,22-dien-3-ol,(3β,22E,24S) were determined. The extracted steroids showed different results regarding the growth inhibition and bactericidal effect on Gram negative (Escherichia coli, Klebsiella pneumoniae and Vibrio harveyi) and Gram positive (Micrococcus roseus and Staphylococcus aureus) bacteria at different experimental doses. In conclusion, promising results were found regarding the antimicrobial effects of the extracted steroids of the marine sponge from Larak island A. sinoxea. These findings reveal the necessity of more comprehensive investigations for the synthesis of pharmaceutical and antibiotic materials from the  bioactive compounds.

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Squalene is an unsaturated triterpene hydrocarbon and is a precursor of steroids and cholesterol with antioxidant properties. The aim of this study was to isolate the squalene from the liver of the Persian Gulf spot tail shark Carcharhinus sorrah and to investigate its antimicrobial activity. Extraction was first done by methanol 70% and then, the squalene was separated through column chromatography with silica gel. Identification of the extracted squalene was done by thin layer chromatography (TLC) and gas chromatography coupled with mass spectrometry (GC–MS). Antibacterial properties of the squalene were identified and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were investigated by tubular dilution. Identification of the extracted compounds by GC-MS confirmed the presence of the squalene in the shark liver. Antibacterial studies showed that the squalene inhibited the growth of Gram negative (Escherichia coli, Klebsiella pneumonia and Vibrio harveyi) and Gram positive (Micrococcus roseus and Staphylococcus aureus) bacteria. Therefore, this metabolite has the potential to be more investigated for developing new antimicrobial compounds.

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Piscidin has a wide range in killing microorganisms including bacteria, fungi, viruses, parasites and has strong anti-tumor activity and plays a role in increasing innate immunity and also does not provide resistance against bacteria; Therefore, it is of great importance in aquaculture. In this study, piscidin gene of Sparus aurata in vector pTZ57R / T was cloned. In this research, ligation product was transferred to component cell of E. coli DH5α strain. Plasmid extraction was performed from single colonies observed in ampicillin plate. Confirmation of the accuracy of single colonies grown in this research was performed by direct PCR and sequencing. The amplified cDNA fragment of the gilthead seabream piscidin gene consists of 310 nucleotides and 57 amino acids. The results of this research show that piscidin gene has been successfully cloned in pTZ57R / T vector. Comparison of nucleotide sequence of piscidin gene in this study showed high similarity with piscidin 5  of Morone chrysops. The comparison of the amino acid sequence of signal peptide piscidin is quite similar to Dicentracin-like of that species registered in the genebank, and mature peptide piscidin sequence is similar in only three amino acids to Pleorocidin-like of Poesila farmosa and Dicentracin-like of Sphaeramia orbicularis. This study could be a step towards further studies of piscidin peptide.

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The present study aimed to isolate the steroids and fatty acids from the liver of the Persian Gulf spot tail shark Carcharhinus sorrah and to assess their antifungal activity. Extraction was done by methanol 70% and then, the lipids were separated through column chromatography with silica gel. Identification of the extracted lipids was done by thin layer chromatography and gas chromatography coupled with mass spectrometry. Then, antifungal activity of the steroids was investigated through determining the minimum inhibition concentration and minimum fungicidal concentration by tubular dilution method against Aspergillus fumigatus and Candida albicans. Identification of the extracted compounds by GC-MS confirmed the presence of these steroids in the shark liver. The identified steroids included compounds of Y-Sitosterol, Desmosterol and Squalene, which showed different results regarding the growth inhibition and fungicidal effects against the microorganisms at different experimental doses. Desmosterol and Squalene at minimum concentration induced the highest inhibitory effect on the fungus but Y-Sitosterol induced the highest inhibitory effect on the yeast. Squalene showed fungicidal effect only on the fungus and totally, A. fumigatus was more sensitive to the antimicrobial activity of the liver compounds than C.  albicans. In conclusion, promising results were found regarding the antimicrobial activity of the lipid compounds derived from Persian Gulf shark liver, revealing the importance of more comprehensive investigations of these natural compounds for the synthesis of biomedicines from the marine organisms.
 

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The indirect application of silver nanoparticles (AgNPs) in controlling the common fungal infection during the incubation period of Persian sturgeon -saprolegniasis - was investigated in this research. Filters containing 0.2%, 0.5% and 1% of AgNPs in two states without agent and with aminopropyltriethoxysilane (APTES) coupling agent along with the control treatment (without filter) were the treatments investigated in the present study. The results showed that in the first 48 hours of incubation, which corresponds to embryonic growth before the start of neurulation, despite the start of contaminating the water in the incubators with Saprolegnia fungus, fungal infection was not seen in any of the investigated treatments. The results of measuring the amount of silver released from the studied filters at the end of the first 12 hours of incubation showed that the amounts of silver released in the water in the treatments of 1% AgNP filters without APTES and with APTES were significantly higher than other filters containing AgNPs. This trend was repeated at the next sampling rounds (48 and 96 hours) with the difference that the release rate was significantly higher only in the 1% AgNP-APTES filter treatment. In the treatment of AgNP-APTES filters, the percentage of hatching showed a significant increase compared to the control filter treatment.