Environmental changes generate free radicals and reactive oxygen species (ROS), resulting in abiotic stress in plants and fungi. Gamma ionizing radiation generates a significant amount of free radicals and ROS, thereby simulating natural environmental stressors. We used a 60Co source of radiation to experimentally induce oxidative stress in living mycelium mass of the medicinal fungus Fomes fomentarius, in order to obtain a late response of stress tolerance by means of bioactive compounds synthesis. We measured the response at 24, 48, and 72 h after the irradiation. The highest improvement was found 24 h after exposure for antioxidant activity and for total phenolic compounds of methanolic extract, with a 1.89- and 1.64-fold increase, respectively. The total flavonoids in methanolic extract increased 1.68 times after 48 h from treatment and presented a more stable raising in the assessed time-lapse. For the three analyzed parameters, 300 Gy was the optimum absorbed dose to trigger a beneficial response, with potentially applications in pharmaceutics and nutraceutics. Gamma irradiation can be used as a biotechnological tool to direct the secondary metabolites synthesis upregulation in medicinal mushroom living mycelium.

Fish are able to accumulate by ingestion various contaminants of aquatic environment, with negative consequences on their intestine, being continuously threatened worldwide by heavy metals, pesticides and antibiotics resulted from the human activities. Consequently, the health of other species can be affected by eating the contaminated fish meat. In this context, our study aimed to perform a comparison between the changes in intestine samples of Carassius gibelio individuals collected from different artificial lakes in Bucharest (Romania), used by people for leisure and fishing. The presence of various metals, pesticides and antibiotics in the gut of fish was assessed in order to correlate their accumulation with changes of antioxidative enzymes activities and microbiome. Our results showed that fish from Bucharest lakes designed for leisure (Chitila, Floreasca and Tei lakes) have an increased level of oxidative stress in intestine tissue, revealed by affected antioxidant enzymes activities and GSH levels, as well as the high degree of lipid peroxidation, compared to the fish from protected environment (Vacaresti Lake). Some heavy metals (Fe, Ni and Pb) and pesticides (aldrin and dieldrin) were in high amount in the gut of fish with modified antioxidative status. In conclusion, our study could improve the knowledge regarding the current state of urban aquatic pollution in order to impose several environmental health measures.

This paper confirms the presence of steppe polecat Mustela eversmanii in Giurgiu County after more than 50 years. Mustela eversmanii is considered a vulnerable species, being listed in Annexes II and IV of the Habitats Directive. The specimen was found within the Site of Community Importance - ROSCI0043 Comana, included in the Natura 2000 network, which significantly overlaps with the protected natural area (Comana Natural Park). Currently, the steppe polecat is not added to the list of the Standard Form, because its presence was uncertain. We consider that this discovery is valuable and has important implications for the conservation of the species.