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The accumulation of nanoparticles in the environment and aquatic ecosystems due to their wide application in industries, agriculture, medicine and pharmaceuticals has caused an increasing concern about the environment and increasing exposure to nanoparticles in ecosystems and humans. Iron oxide nanoparticles easily enter the bloodstream, accumulate in different tissues and cause damage to these tissues. Therefore, in this research, changes in the intestinal tissue of gray mullet fish (M. cephalus) and tissue accumulation in oral exposure to iron oxide nanoparticles were investigated.
110 pieces of young gray mullet after 2 weeks of adaptation were treated in four-time groups of 1, 7, 14 and 28 days, and one group was considered as a control. The mullet fish received iron oxide nanoparticles twice a day at the rate of 15 mg/kg attached to the food. The results showed that although the amount of tissue iron increased significantly only in the 28-day group, the consumption of iron oxide nanoparticles in almost all groups increases the tissue accumulation of iron in the intestine. The intestinal histological study showed changes such as the increase in the number and size of goblet cells, destruction of microvilli structure, bleeding and degrees of necrosis, and the intensity and extent of the changes in the intestinal tissue increased with increasing exposure time.
These observations showed that the consumption of iron oxide nanoparticles has a negative effect on intestinal function and causes iron accumulation and the occurrence of time-dependent injuries.

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      In this study, proteolytic extract from Withania coagulans (at levels of 1, 2 and 3%) as a microbial rent substitute, with inulin (at levels of 0.5, 1 and 1.5%) as a prebiotic in Cheese making was used. All cheese samples prepared with plant extracts were compared in terms of physicochemical properties, color parameters, texture and sensory properties. The results of analysis of variance showed that with the addition of plant enzyme and inulin and increasing both variables, the pH decreased and the acidity increased. In cheese samples prepared with plant enzyme and containing inulin, the amount of moisture increased with increasing plant enzyme and the amount of moisture decreased with increasing inulin. With increasing both variables, the amount of synersis and L * decreased. None of the process variables had a significant effect on the amount of a* and the addition of enzyme increased and inulin decreased the yellowness (b *), also had a significant effect on tissue properties except elasticity. With the addition of plant enzyme, the amount of stiffness and cohesiveness decreased and with the addition of inulin to the samples, the amount of stiffness and cohesiveness of the samples increased and the amount of chewiness and gumminess in different concentrations of inulin increased. The results of this study showed that proteolytic extract of Witania coagulans is a suitable alternative for microbial rent and also the use of inulin with it can lead to the production of probiotic cheese with suitable textural and sensory properties.