فصلنامه فیزیولوژی و بیوتکنولوژی آبزیان
سال هشتم شماره 4 (زمستان 1399)

The present study was carried out to determine the effect of emulsified OvaprimTM with almond oil on spawning induction of Abramis brama, as well as, the spermatological parameters of males. In the first (C), second (OO) and third (OS) treatments, females were injected with 1mL.kg-1 body weight (BW) of bitter almond oil, 1mL.kg-1 BW OvaprimTM with almond oil (1:1) and 1mL.kg-1 BW OvaprimTM with 0.9% NaCl solution (1:1), respectively. In each treatment, 10 females (weight range between 802 to 934g) were injected. Moreover, 26 males were injected in two replicates with 0.6mL.kg-1 BW by OvaprimTM with 0.9% NaCl solution (1:2). Based on the results, the highest ovulation rate was observed in OS treatment (100%) and the lowest ovulation rate was observed in control group (0%) (P<0.05). Moreover, there was a significant difference between OO (722.5±68.4 degree-hour) and OS (578.0±44.2 degree-hour) treatments in latency time (P<0.05). The significant difference was observed between control group (0g) and OO (52.4±34.6g) and OS (72.3±0.2g) treatments in average weight of obtained eggs (P<0.05). The significant differences were not found between OO and OS treatments in absolute fecundity, relative fecundity, the average number of eggs per gram, fertilization rate, and incubation period (P>0.05). Based on the results of this study, the mean of sperm volume, sperm activity, motility time, spermatocrit value, and spermatozoa concentration of Abramis brama were 13.6±5.9mL, 56.7±12.1%, 95.2±17.6s, 30.0±8.8%, 11.0±3.3×109mL-1, respectively. According to the results, it is recommended that the emulsified OvaprimTM with oil can be used to induce spawning of bream in hatcheries.

The aim of this study was to investigate the effect of bovine serum albumin (BSA), lecithin and trehalose on qualitative indices of freeze-thawed Acipenser persicus sperm. In this regard, sperm samples prepared from 5 male A. persicus and the samples were frozen after dilution with various extenders. After 3 months of freezing, the freeze-thawed sperm quality indices were evaluated by Image J software and mitochondrial activity by using the fluorescent staining JC-1 method. Results of sperm motility showed rotational motions in treatment BSA and linear motions in treatment “BSA + trehalose”. Analysis of motion parameters in freeze-thawed sperm showed that the treatment “BSA + trehalose” had the highest arc velocity (1.74μM/s), highest linear velocity was in BSA and trehalose treatments (0.30µM/s) and the highest linear movement was seen in trehalose and trehalose + lecithin treatments (23.87 and 25.48%, respectively). Results of the effect of preservatives on sperm motility showed the highest percentage in treatment “BSA + trehalose” (3.49%) and the highest mitochondrial activity in trehalose treatment (10.58%). Therefore, the use of BSA with trehalose can have a potential impact on reducing cell damage during cryopreservation, the protection and development of this valuable species of Caspian species.

This study was performed to investigate the chemical composition of the caudal spine in Hemitrygon bennettii (Muller and Henle, 1841) as a source for hydroxyapatite (HA) extraction. Therefore, the chemical structure of caudal spines of fish sampled from the mangrove swamps at Chabahar Bay was determined at calcined (baked at high temperature) and uncalcined conditions. The Raman spectroscopy and ICP-OES were used for structural and elemental analyses, respectively. The sharpest peaks in the Raman were observed at 962cm-1 which was probably due to the symmetric stretching vibrations of apatite phosphates. The adsorbed OH ions also indicated peaks at 3400-3500cm-1 of both calcined and uncalcined samples. The presence of organic residue in uncalcined samples was highlighted by several peaks at 2700-3050 and 1300-1500cm-1 which may be due to both stretching and bending vibrations of CH, CH2 and CH3 groups. Some peaks at 1200-1800cm-1 may also be related to amine residues of proteins. In terms of ion concentrations, high amounts of sodium and magnesium contents in the spine structure (compared to other natural resources of HA extraction) may improve the biocompatibility of extracted HA.

The cyprinodontid fishes belong to the order Cyprinodontiformes (Teleostei) and consisting of small fishes, which has aesthetic value, and also are important in biological control and also in ecological and bio-medicine researches. The genus Aphanius has already been in the family Cyprinodontidae but it has recently been placed in the family Aphaniidae. To evaluate the phylogenetic validity of the new family Aphaniidae in this study, seven families of the order Cyprinodontiformes were selected and their phylogenetic relationships were analyzed. The phylogenetic tree was estimated based on a data set, including the complete mitochondrial genome genes from the database as well as the complete mitochondrial genome of Aphanius farsicus as representative of the family Aphaniidae. The phylogenetic analysis indicates a close relationship between the genera Aphanius (Aphaniidae) and Cyprinodon (Cyprinodontidae) so that the group containing these two families was paraphyletic. Therefore, by considering the phylogenetic position of the genus Aphanius in the tree, the validation of the family Aphaniidae still needs more phylogenetic supports and it should be investigated by accumulating more sequences from the Aphanius species.

Azo dyes are the most important and widely used dyes in various industries. This group of pollutants is a threat to aquatic life. In the present study, the effect of three different concentrations (0, 10, 20mg/L) of the basic red 46, (BR46) on the physiological characteristics of aquatic fern Salvinia natans was evaluated at the 7-day treatment period. Also, the ability of S. natans for bioremoval of BR46 was evaluated. The results showed that chlorophyll a and total chlorophyll content, despite chlorophyll b, decreased at 20mg/L concentration. At 20 mg/L of BR46, relative growth rate and effect index decreased and increased, respectively. Total carotenoid concentration was increased by 72% at 20mg/L. Cyanidine glycoside concentration, lipid peroxidation and antioxidant activity increased in the presence of 10 and 20 mg/L of BR46. On day 7th, the highest bioremoval efficiency was observed in the presence of 20mg/L BR46. Thus, S. natans has the ability to remove BR46 from contaminated water but the presence of both 10 and 20mg/L of dye induced antioxidant activity and the risk of oxidative stress for S. natans.

In recent years the advent and spread of diverse multidrug-resistant bacteria have been a main object of concern to the medical field and the public health. Antimicrobial peptides (AMPs) are short, usually positive charge and hydrophobic molecules observed in an extensive array of life forms from prokaryotes to eukaryotes including humans. Introducing the group of molecules has been promising as that has some benefits over the significant world well-being concerns. This research describes the antimicrobial activity of the epidermal exudates extract of Neogobius fluviatilis pallasi and its size-based fractionations for the first time. The results showed that epidermal mucus extract and its fractionations were toxic to Bacillus subtilis and Staphylococcus aureus with radial of inhibition 12.25 and 19.25 mm, respectively. However, Pseudomonas aeruginosa, Escherichia coli, Vibrio harveyi, Yersinia ruckeri were resistant. Proteolytic treatment with proteinase K led to depleting the antibacterial properties of fractions, indicating that the active agent possess a proteinaceous nature. Overall, these results propose that fish skin mucus is a rich and valuable source for finding novel AMPs with potential applications in aquaculture and medicine.

Today, due to increase in resistance of antibiotics, it is necessary to find suitable alternatives to natural materials. Algae also have many applications in medicine, pharmacy and the food industry.  Therefore, the present study was performed to investigate the antibacterial activity of red algae Gracilaria gracilis extract. In this study, the active compounds of methanolic extract of red algae G. gracilis were identified by gas chromatography-mass spectrometry (GC/MS). The Antimicrobial effect of algae extract on bacteria were investigated by sequential dilution method. The chemical analysis of the algae extract compounds showed that the major components of the extract were phenylethine, silacyclopntenen, phthalic acid, n-hexadecanoic acid, dibutyl phthalate, phytol and gibberellin. In the study of minimum inhibitory concentration and minimum bactericidal concentration, it was shown that Pseudomonas aeruginosa and Staphylococcus aureus with algae extract with a minimum inhibitory concentration of 6.2 and 112.5 mg/mL, respectively, compared to other studied bacteria, showed more sensitivity. Based on the results, the methanolic extract of red algae G. gracilis had good antimicrobial activity. Therefore, clinical research is necessary for the clinical applications of this extract.