No abstract

Despite several studies on fish hormone therapy, finding new candidates may provide more reproductive efficiency in artificial propagation. Kisspeptins, being upstream of the hypothalamic–pituitary‐gonadal axis, appear to play a key role in the reproduction process. In the present study, the effect of different variants of kisspeptide, including goldfish (Carassius auratus) kiss1 kisspeptin (Kiss1), human kisspeptin (Hkiss), and their combination (Kiss1 + H), on the reproductive indices of goldfish broodstock in comparison to Ovaprim (a typical synthetic Gnrh hormone) was investigated. Peptides (Kiss1 and Hkiss) were synthesized using a solid‐phase synthesis approach. Kiss1 and Hkiss were injected at a dose of 100 μg kg−1 body weight, blood samples were taken 6 h after injection and sex hormones (E2, Dhp, and 11‐Kt), gonadotropins (Lh and Fsh), cortisol and reproductive indices (fecundity, fertilization and hatching percentage) were measured. The results showed a significant increase of plasma sex hormones and gonadotropins in fish treated with kisspeptins. In addition, the cortisol and lipoprotein lipase in Kiss1, Hkiss and Kiss1 + H were remarkably increased compared to Ovaprim. In conclusion, kisspeptins could be a more suitable candidate than Ovaprim for accelerating and synchronizing oocyte maturation in the fisheries industry.

Background: The present study was carried out to test the antibacterial effect of the body wall of the sea cucumber Holothuria leucospilota Brandt on Streptococcus mutans and Streptococcus salivarius. Methods: After sampling sea cucumbers from the Persian Gulf, different extractions were prepared. Then, aqueous, phosphate-buffered saline (PBS, pH 7.8), chloroform, hexane and methanolic extracts from sea cucumber body wall were screened for antibacterial activity against pathogenic bacteria S. mutans and S. salivarius using the disk diffusion method. Results: The PBS extract did not show any antibacterial or inhibitory activity; the chloroform extract, however, demonstrated high levels of antibacterial activity against S. salivarius while exhibiting low levels of activity against S. mutans. The hexane and methanolic extracts were found to show no antibacterial activity against S. mutans, but exhibited antibacterial activity against S. salivarius. Conclusions: In conclusion, the results demonstrated the possibility of utilizing sea cucumbers as a cheap source of potential antibacterial agents and for treating odontogenic diseases.

In this study, the antibacterial and hemolytic effects of the gonadal tissue, test, spines and Aristotle's lantern of the sea urchin (Echinometra mathaei) were investigated. The aerobic Gram-positive pathogenic bacteria Streptococcus mutans and Streptococcus sobrinus were selected because of their importance in oral diseases. The samples of sea urchin were collected from an intertidal zone in the Persian Gulf and then dissected. Finally, the crude extracts of the gonadal tissue, test, spines and Aristotle's lantern of the samples were separately prepared by the solvents, including phosphate-buffered saline (PBS), 96 % ethanol (Et) and 80 % acetonitrile (ACN). The antibacterial activities of the extracts were evaluated using the well diffusion method in two concentrations of 1500 and 600 lg well -1 . The antibacterial effects against streptococcal species were observed in the organic extracts (Et and ACN) of the gonads and test while the extracts of spines and Aristotle's lantern showed no antibacterial activity. The hemolytic activity of the PBS, 96 % Et, and 80 % ACN extracts from the sea urchin were evaluated using horse red blood cells. Hemolytic activity was observed only in the 80 % Et and ACN extracts of the gonad and test. In conclusion, the organic extracts of gonadal tissue showed the most inhibitory activity on the growth of S. mutans and S. sobrinus.

Holothurians (sea cucumbers) exist almost in all benthic marine environments and they are an important species for the commercial fisheries. In this study, the antimicrobial activity of different tissues of the sea cucumber, as a marine invertebrate, was investigated. The bacteria, Streptococcus mutans and Streptococcus sobrinus, the fungi, Candida parapsilosis, Candida albicans and Candida glabrata, were chosen for antimicrobial test, because they are opportunistic pathogens. The body wall, respiratory tree, and gastrointestinal tract of the sea cucumbers were utilized to make the extracts. Phosphate-buffered saline (PBS), ethanol (Et), and acetonitrile (ACN) were used as solvents for aqueous and organic extractions. The results showed that there were antimicrobial active compounds against infective streptococci and candid fungi. Streptococcus mutans was generally more tolerant than Streptococcus sobrinus to the sea cucumber extracts. The extracts of the respiratory tree with ACN and PBS, as solvents, showed the highest effect against Candida albicans, Candida parapsilosis and Candida glabrata. The extracts of gastrointestinal tract and the body wall with Et and PBS, respectively, had not any antifungal activity. The antimicrobial activities had been found in different extracts of the sea cucumber tissues, which could be related to the protein and non-protein compounds.

In this study, non–specific immune parameters in fertilized eggs, eyed embryos, larvae 10, 25, 50, 60, and 70 days post hatch (DPH), and female broodstock of Caspian kutum, Rutilus frisii kutum (Kamensky), were evaluated. The lysozyme activity, complement C3, and total protein levels were measured with the turbidimetric, immunoturbidimetric, and Bradford methods, respectively. The results showed that lysozyme levels decreased from levels noted in the fertilized eggs until the larvae were 10 days old. Subsequently, significant increases in lysozyme levels were observed until 70 DPH. An increasing trend of complement component C3 was noted from the levels in fertilized eggs to 10 DPH, following which it decreased significantly. Total protein levels differed significantly in early developmental stages of Caspian kutum. The higher values of complement component C3 than of lysozyme in the early life stages could be indicative of the former’s more fundamental role.

No abstract

No abstract