amireghbal khajeh rahimi

The aim of this study was to identify and analyze the chemical composition of pumpkin seed extract (Cucurbita pepo) and to evaluate its effect on hematologic factors and growth indices in rainbow trout (Oncorhynchus mykiss). The extract was prepared and analyzed using standard chemical methods and the fish were divided into four groups (one control and three treatments). Blood factors and growth indices were measured on days 0, 30 and 60. The results showed that treatment with pumpkin seed extract significantly increased hematological parameters such as RBC and PLT as well as improved growth indices. This study shows that pumpkin seed extract contains chemically active compounds that can be effective in improving the health and growth of farmed fish.

Contamination of food products, especially dairy products, with aflatoxins, is one of the main problems in the food industry. This research aimed to remove aflatoxin M1 using two probiotics, Bifidobacterium lactis and Streptococcus thermophilus, either alone or in combination, in skimmed milk containing this toxin. The study investigated the effects of storage time, microbial strain, bacterial concentration, toxin concentration, and temperature on the removal of aflatoxin M1. Two probiotic bacteria, Bifidobacterium lactis and Streptococcus thermophilus, at dilutions of 108 and 1010 CFU/ml, were inoculated alone and in combination into skimmed milk contaminated with different concentrations of aflatoxin M1 (0.1, 0.25, and 0.5 μg/ml). The samples were then incubated at 4°C and 37°C for 0.5, 1, 2, and 24 hours. The detoxification percentage of aflatoxin M1 was measured using high-performance liquid chromatography (HPLC). The results showed an increase in the removal of aflatoxin M1 with time. The removal of aflatoxin M1 by these strains varied from 12% to 87% depending on the concentration of bacteria, storage time, toxin concentration, and bacterial strain, whether alone or in combination. The results of this study suggest that using probiotics can be an effective method for reducing or eliminating the concentration of aflatoxin M1 in the dairy industry.

Food contamination with aflatoxin is identified as a challenge for health and economics; therefore, global organizations have determined the minimum contamination of different foods. Aflatoxin M1 (AFM1) is a carcinogenic mycotoxin mostly found in dairy products and its removal has remained a challenge. This study aimed to evaluate the effect of anti-aflatoxin of Bifidobacterium bifidum and Saccharomyces cerevisiae in contaminated skim milk.

In order to carry out this project, skim milk was spiked with three concentrations of AFM1 and treated with two levels of bacteria and fungi concentration, alone or mixed, and incubated at 4 and 37 ˚C for different time points (30, 60, 120 min, and 24h). High-performance liquid chromatography (HPLC) was used to detect the AFM1 in milk.

The results showed that the incubation time is a key factor in the removal process of AFM1. Also, the removal of AFM1 was dependent on other factors such as the concentration of microorganisms, incubation temperature, toxin concentration and type of treatment (alone or combination). The ability of these strains to remove AFM1 after 24 hours was shown to be 20-90%. The removal of AFM1 by Saccharomyces cerevisiae (66.8%) as compared to Bifidobacterium bifidum (51.3%), and the combination of probiotics increased their ability to remove the toxins (90%).

The results of this study showed that probiotics alone or in combination with each other play an essential role in removing AFM1 from milk.

Food products spoil very quickly due to microbial, chemical, and enzymatic reactions that are the main cause of rapid quality deterioration. Nowadays, there is increasing consumer demand for high-quality foods with natural preservatives such as microalgae extracts. Microalgae are potential alternatives to reduce microbial growth, increase oxidative stability, and protect the sensory characteristics of foods. Researchers showed that the use of microalgae extracts in the diet of aquatic animals can increase meat quality and production. In this review article, the direct application of various microalgae extracts as seafood preservatives and their functional properties in seafood, such as: (antioxidant and antimicrobial activities) are investigated. In addition, the potential application of microalgae extracts in the composition of foods and their effect on the quality of foods are also presented. The result of reviewing many articles showed that despite the many advantages of microalgae, there are still many challenges in the production and use of microalgae biomass or its derivatives in the food industry, hence the safety assessment and the use of ideal concentrations for studies. Future studies are still necessary to determine the optimal concentration for the large-scale use of microalgae extracts in industry and seafood, to develop effective strategies or to prevent the occurrence of food product spoilage, as well as to increase the welfare of consumers.

Lactobacillus plantarum probiotic is one of the probiotics used in aquatic nutrition. The aim of this study was to evaluate the effect of L. plantarum probiotic on the growth indices and blood parameters in juvenile common carp (Cyprinus carpio).

In this study, 180 juvenile common carp (Cyprinus carpio) with a mean weight of 15.32±0.16 g were randomly assigned to two experimental treatments with three replicates (30 pieces per repetition) including a commercial diet (control treatment) and a diet containing L. plantarum probiotics at 107 CFU/g (experimental treatment). The duration of the study and treatments was 60 days.

The final weight, weight gain, specific growth rate, status index, and feed conversion ratio in the treatment containing L. plantarum had a significant increase compared to the control group (P <0.05). Also, the addition of L. plantarum probiotic to juvenile common carp diet increased the number of white blood cells compared to the control group (P<0.05); while it had no significant effect on other blood parameters.

The present findings showed that the use of L. plantarum probiotic improved growth indices (final weight, weight gain, specific growth rate, condition index, and food conversion ratio) and also increased the number of white blood cells in juvenile common carp (Cyprinus carpio).

This study was performed to evaluate the effect of feeding with Oregano Vulgare essential oil supplementation on the brain tissue of Koi fish under long-term exposure to naproxen. For this purpose, 135 Koi fish (Mean weight: 1.5 gr; Average length: 6±1 cm) were divided into three groups with three replications. These fish were fed with two diets including a basic diet (BD) and an essential oil diet (OED) for 30 days. They were then exposed to naproxen (NP) for 14 days. Treatments included a control group (C): BD feeding, T1 group: BD feeding and NP toxicity, and T2 group: OED feeding and NP toxicity. Brain tissue sampling was performed at the end of the experiment. Tissue samples were examined after fixation in Bowen's solution and preparation of histopathological slides. The most common complications in T1 treatment were gliosis, vacuolation, necrosis, inflammation, and hyperemia. These complications were observed in T2 with a less destructive effect than in T1. These results showed the positive effect of feeding with oregano essential oil in reducing tissue damage exposed to NP toxicity in Koi fish. Due to the widespread use of NP and the persistence of this drug in the surface waters of the world, it is important to investigate the effects of this drug contaminant on non-target organisms. Therefore, it is necessary to identify and introduce practical strategies to reduce the adverse effects and economic losses of toxicities with these pollutants.

Nowadays algae, which are Phototroph  diatom, are capable of converting nonorganic photos into organic matter, have found many applications in the food, pharmaceutical and sanitary industries. In this study, the effect of adding different levels of Dunaliella salina microalgae biomass on the physicochemical and sensory properties of yogurt during a 21-day storage period was investigated. Dunaliella salina mass powder was added to milk at 4 levels (0, 0.5, 1 and 2% by weight) in the pre-pasteurization stage. Tests including pH measurement, water holding capacity, tissue measurement and colorimetry of samples performed on the first, seventh, fourteenth and twenty-first days after production and evaluation of viscosity and sensory characteristics on the first day after production on the produced yogurt. The results showed that the addition of Dunaliella salina biomass at different levels caused a significant decrease in pH. The water holding capacity of the samples decreased with increasing algal level and storage time (P <0.05). The amount of stiffness, viscosity and color parameters of the yogurt samples showed a significant decrease with increasing algal surface (P <0.05). Sensory evaluations showed that with increasing biomass levels, sensory scores and overall acceptance from consumers decreased. Due to the unique nutritional properties of Dunaliella salina powder, the use of bioactive compounds of this microalgae can also be one of the proposed approaches for use in various food products, including yogurt.

< p >The aim of this study was to isolate polysaccharides from the Typha stem to evaluate its technological specifications and antibacterial and antioxidant activities. To isolate this polysaccharide, we used the alkaline- ultrasonic extraction method in this state; water to raw material ratio is 25 mL/g, sodium hydroxide concentration 1.5 M for 40 min. The dynamic light scattering results illustrated that the average particle size and zeta potential were 282 nm and -21.52 mV, respectively. Based on the results, the Hausner''s ratio and Carr’s Index were 1.16±0.02 and %13.99±0.01, respectively. This polysaccharide showed a high capacity for water holding (9.28±0.15), oil holding (4.37±0.14), Emulsifying (100%) and emulsion stability (96%). Also, the results of this study showed that the extracted polysaccharide has a high ability to scavenge free radicals ABTS (IC50=0.47 mg/mL). Examination of antibacterial activity by disk agar diffusion method showed that this compound did not have a significant effect, on inhibiting the growth of selected bacteria in this study. Therefore, this polysaccharide can be introduced as a natural source of antioxidant and an appropriate composition for technological uses.

This research was conducted to evaluate the diet of juvenile roach (Rutilus caspicus) stocked in earthen ponds and improve the pond conditions to increase the dominant organisms species. Four earthen ponds with the same hydrobiological properties were studied in the Syjwal bony fish farm. Sampling of the food organisms, measuring the weight and length of the juvenile roaches, and gut examination were carried out over a four-month period from March to June. The results indicated that the highest and the lowest condition factors (K) were 1.196 and 0.633, respectively; while the highest dominance index (Ip) was reported as 42.14 for Gastropoda and the lowest dominance index was reported as 2.4 for aquatic insects. The results of (Fp) analysis showed that the gastropoda and crayfish were mainly considered as the major preys, and organisms such as aquatic insects and bivalves were found as the minor foods in the Syjwal earthen ponds. Evaluation of the food preference (Fp)and the gut content of juvenile roaches in different stages indicate that the gastropoda show a higher food preference and feeding intensity than the other Foods.

Cryopreservation of ovarian tissue or follicles has been proposed as an alternative method for fertility preservation. Although successful vitrification of follicles has been reported in several mammalian species, the survival rate is generally low. The aim of this study was to investigate the effects of fibroblast growth factor (FGF) and epidermal growth factor (EGF) on in vitro preantral follicle development after vitrification.In this experimental study, preantral follicles with diameter of 150-180 μm were mechanically isolated from ovaries of 18-21 days old NMRI mice. Follicles were vitrified and warmed, then cultured in α-minimal essential medium (α-MEM) without growth factor supplementation as control group (group I), while supplemented with 20 ng/ml FGF (group II), 20 ng/ml EGF (group III), and 20 ng/ml FGF +20 ng/ml EGF (group IV). After 12 days, human chorionic gonadotrophin (hCG)/EGF was added to culture medium, and after 18-20 hours, the presence of cumulus oocyte complexes (COCs) and oocyte maturation were assessed. The chi-square (χ2) test was used to analyze survival and ovulation rates of the follicles. Our results showed that the rate of metaphase II (MII) oocytes in FGF group increased in comparison with control and other treatment groups (p<0.027), but there was no difference between control with EGF and EGF+FGF groups in oocyte maturation rate (p>0.05). There was a significant decrease in survival rate of follicles in EGF+FGE group in comparison with other groups (p<0.008). After in vitro ovulation induction, the follicles in EGF group showed a higher ovulation rate (p<0.008) than those cultured in other groups. FGF has beneficial effect on oocyte maturation, and EGF increases COCs number in vitro. Combination of EGF and FGE decreases the number of survived follicles.