فصلنامه فیزیولوژی و بیوتکنولوژی آبزیان
سال یازدهم شماره 3 (پاییز 1402)

It is crucial to investigate the amount of metals in the muscle tissue of common carp (Cyprinus carpio) because of their high consumption in Sistan region, from Hamoun international wetland in wet years. Therefore, in the present study, C. carpio was captured from Hamoun Pouzak, Hirmand and Sabouri and prepared through acid digestion method and the concentration of heavy metals was measured using ICP. Statistical analysis showed the significant difference among three lakes in which Sabouri lake had the highest metal concentration (P<0.05). Also, the accumulation patterns of metals in the muscle tissue were Zn>Fe>Cu>Mn>Cr>Ni>Pb>Cd. The amount of Ni, Cr and Mn were higher than the WHO and FAO guidelines. The maximum amounts of THQ for Cd in infants and adults were 2.458 and 0.097, respectively. In addition, the HI measured in adults was <1 and showed no health risk in 227g consumption rate. While, it’s calculated with an amount of 6.08 in infants. In conclusion, the consumption of C. carpio may cause health effects in infants, especially for Cd.

Marine polysaccharides are natural bioactive compounds with valuable applications. In the current study, sulfated polysaccharide from green alga Ulva intestinalis was extracted using water-based solvents, and some of its properties such as functional groups, antibacterial activity, and its ability to inhibit the western white shrimp polyphenol oxidase enzyme were measured. The results of Fourier transform infrared spectroscopy (FT-IR) confirmed the presence of sulfate-containing functional groups in the polysaccharide. Sulfated polysaccharide in both concentrations of 25 and 50 mg/mL showed antibacterial activity against 2 strains of gram-positive bacteria Micrococcus luteus and Staphylococcus aureus and 2 strains of gram-negative bacteria Escherichia coli and Salmonella typhimurium (P<0.05). Also, this combination with a concentration of 1.5% after 1 and 3 minutes showed the highest ability in inhibiting the activity of the western white shrimp polyphenol oxidase enzyme with 63.03 and 48.74%, respectively, compared to other concentrations (0.05>P). In general, according to the results of the present study, the use of sulfated polysaccharide obtained from green alga U. intestinalis is suggested in the shrimp processing industry.

This study was conducted to evaluate the effect of fish meal replacement by Aqupro (processed soybean meal) on hematological and biochemical indices of juvenile Siberian sturgeon (Acipenser baerii). To do this, 105 juvenile Siberian sturgeon (initial body weight 171.79±1.07g) were distributed in five treatments each with three replicates. The experimental treatments included the control (AP0), 20 (AP20), 40 (AP40), 60 (AP60) and 80 (AP80) percent replacement of Aqupro substituted with fish meal. Fish were fed according to apparent satiation four times daily for 12 weeks. According to the results, the highest final weight was observed in the control treatment (252.95±27.00g) and among the treatments containing Aqupro, the highest and lowest weights were observed in AP60 (226.38±14.71g) and AP40 (211.09±4.14g), respectively, but no significant difference was observed in any treatments (P>0.05). Hematological results showed significant differences in the number of white blood cells and differential white blood cells in some treatments with the control group (P<0.05). The percent of lymphocytes showed no significant difference between treatments and control (P>0.05), but AP20 and AP40 showed significant differences with AP60 and AP80 (P<0.05). There were no significant differences in the number of red blood cells, hemoglobin, hematocrit, MCV, MCH and MCHC among treatments (P>0.05). The highest cholesterol level was observed in AP60 and showed a significant difference with control (P<0.05). Glucose levels showed significant differences between different treatments, as the lowest level was found in AP80 and indicated a significant difference with control (P<0.05). No significant differences were observed in plasma triglyceride and proteins (total protein, globulin and albumin) compared with control (P<0.05). According to the results of this study, due to the importance of fish meal and its high price, nutritional value of Aqupro and easy accessibility and also no negative impact on measured indices, replacement of high levels of fish meal with Aqupro is possible in Siberian sturgeon diet.

Today, green synthesis by using plant extracts to produce nanoparticles has attracted a lot of attention, because of fast reaction, economy and compatibility with the environment. Therefore, in the present study, the anticancer effect of biosynthesized silver nanoparticles with aqueous and methanolic (80%) extracts of green algae Spirogyra sp. was investigated on MDA-MB-231 human breast cancer cells. The GC-MS spectrometer chromatogram of the extract of this alga showed that Nonadecane (14.86%), Heneicosane (10.24%) and Tridecane, 6-phenyl (5.44%) have the highest percentage. Silver nanoparticles were synthesized by adding aqueous and methanolic extracts of algae to silver nitrate and their physical and chemical properties were determined by UV/Vis spectrophotometry, FTIR, DLS, Zeta potential and FESEM electron microscope. Also, the cellular toxicity of silver nanoparticles at different concentrations was investigated using the MTT method on cancer cells. The results showed that the synthesized silver nanoparticles had maximum absorption at the wavelength of 434nm and an average size of 30 to 79 nm with a spherical morphology. Cytotoxicity of biosynthetic silver nanoparticles against cancer cells has increased with increasing concentration. As a result, biosynthesized silver nanoparticles had anti-cancer activity and can be further studied for the treatment of breast cancer.

Brown seaweeds contain compounds such as alginate and phytohormones that have many uses in industries. This research was conducted to determine biomass and extract two phytohormones and alginate from Sargassum muticum. Sampling was done from January 2014 to November 2015 in Bushehr port, one month apart. Biomass and environmental parameters were measured in the selected transect and the algae were sampled. After extraction, hormones were separated by HPLC and identified by standard injection. The highest biomass of alga was in January (679±2.12g/m2) and the lowest was in September (20.67±0.76 g/m2). Alginate reached the lowest leve (40.67±1.03%) in November and the highest level (54.67±2.25%) in January, which had a positive correlation with biomass. The highest amount of gibberellin (5.86±1.11%) was in July, which had a positive correlation with temperature. Zeatin was obtained only in May (0.18±0.07%). According to the results, in order to extract alginate, gibberellin and zeatin from this alga, it should be done in January, July and May, respectively. Considering the high price and the necessity of using these materials in industries, agriculture and as algae liquid fertilizer, this research is a starting point for extracting substances and hormones from this alga.

Thymol is the main monoterpene phenol occurring in essential oils. The aim of this study was to encapsulate thymol, in natural polymers gelatin and carrageenan. In order to achieve the optimization of encapsulated thymol, the CCD method of the experiment design software was used. As a result, based on the analysis, it was found that the optimal conditions suggested by Design Expert 13 software were as follows: pH 6, thymol concentration 0.4% (W/V) and the ratio of carrageenan to gelatin =1, which in this case, the encapsulation efficiency, nanocapsule size and polydispersity index were obtained 91%, 112 nm, and 1.1, respectively. The encapsulated thymol gave lower minimal inhibition concentration (MIC) and minimal bactericidal concentration (MBC) values than the unencapsulated thymol against Bacillus sp. strain. In addition, encapsulated thymol had 70% inhibition and eradication of biofilm in lower concentrations. In general, the results showed an improvement in antibacterial and antibiofilm activity for nanoencapsulated thymol against marine bacteria Bacillus sp. This formulation could be proposed as an alternative or adjuvant for controlling biofilm in marine bacteria in the first stage of the biofouling phenomenon.