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Does hydrogen-rich water mitigate MP toxicity in rainbow trout (Oncorhyncus mykiss)? Monitoring with hematology, DNA damage, and apoptosis via ROS/GSH/MDA pathway

Atamanalp Muhammed, Kırıcı Muammer, Köktürk Mine, Kirici Mahinur, Alwazeer Duried, Kocaman Esat Mahmut, Ucar Erzu, Parlak Veysel, Özcan Sinan, Alak Gonca

Oceanological and Hydrobiological Studies

2023

Vol. 52, No. 2

206--220

Although the number of studies documenting the presence of Microplastics (MP) in fish is increasing, research studies focused on its detoxification are very limited. In this study, rainbow trout ( Oncorhyncus mykiss) were randomly divided into two groups after being fed with MPs (15% polypropylene [PP] +15% polyethylene [PE]) for 2 months. MP excretion without any application (PP+PE) in group I fish, and excretion of MPs with hydrogen-rich water (HRW) application (PP+PE+HRW) in group 2 were investigated under semi-static conditions for 21 days. This effectwas also compared by using positive and negative control groups (Control[no treatment, free PP, PE or/and HRW] and only HRW group). In thisdirection, the following were determined: PP+PE chronic toxicity in aquatic organisms, the toxicity mechanism and the effect of HRW as a possibletreatment method in blood tissue; with hematological indices ([RBC count [RBC], leukocyte count [WBC], hemoglobin value [Hb], hematocrit ratio [Hct], platelet count [PLT], hemoglobin count per erythrocyte [MCHC],mean hemoglobin amount per erythrocyte [MCH] and mean erythrocyte volume [MCV]) in other tissues (liver, gill and brain tissue) oxidative stress response (catalase [CAT]), glutathione peroxidase (GPx), glutathione reductase (GR), superoxide dismutase (SOD), glutathione (GSH), reactive oxygen products (ROS), malondialdehyde ([MDA] levels), DNA damage (8-OHdG: 8-Hydroxy-2-Deoxyguanosine), and the apoptosis (caspase 3) levels were investigated. In addition, acetylcholinesterase enzyme (AChE) activity, which is important in neurotoxicity pathways in the brain, wasdetermined. The presence of plastics (PP/PE) in target tissues (muscle, liver,gill and gastrointestinal tract) was also obtained.The results showed that PP+PE caused toxicity in all three tissues. MPs showed an inhibiting effect on antioxidant enzyme activities and an inductive effect on MDA, ROS, 8-OHdG, and caspase 3 levels. HRW showed a mitigating effect on MP-mediated toxicity in O. mykiss brain, blood, gill, and liver by controlling the ROS/ GSH/MDA pathway. HRW can be suggested as a cost-effective and eco-friendly curative for the protection of fish from the oxidative damages produced by the ingestion of microplastics.

Tworzenie się wodoru na drodze niskotemperaturowego utleniania węgla kopalnego tlenem z powietrza

Czechowski F., Marzec A., Czajkowska S.

Gospodarka Surowcami Mineralnymi

2007

T. 23, z. 3s

61-74

Przedstawiono wyniki analizy składu atmosfery gazowej utworzonej podczas niskotemperaturowego (50, 70 i 90 C) utleniania węgli kamiennych 20% tlenem w mieszaninie z helem. Badania przeprowadzono na 19 próbkach węgli kamiennych pochodzących z 10 polskich kopalń. Autoutlenianie się węgla tlenem bądź jego niskotemperaturowe utlenianie prowadzi, między innymi, do tworzenia się wodoru, który nie jest składnikiem gazów zaadsorbowanych w strukturze węgla. Równowagowe stężenie wodoru dla wszystkich badanych węgli jest podobne i wynosi 0,5% wodoru w poreakcyjnej atmosferze gazowej reaktora stosowanego do badań, co stanowi 70 L wodoru z tony węgla. Wyjaśniono, że strukturami źródłowymi z udziałem których tworzy się wodór są występujące w węglu nienasycone wiązania podwójne w strukturalnych jednostkach węglowodorów łańcuchowych i alicyklicznych (podstawniki bądź mostki łańcuchowe z wiązaniem nienasyconym lub częściowo zaromatyzowane układy alicykliczne z pierścieniem zawierającym wiązanie nienasycone), do których łatwo przyłącza się tlen prowadząc do powstawania ugrupowań aldehydowych. Silnie reaktywne struktury z grupą aldehydową w reakcji z parą wodną prowadzą do tworzenia się odpowiednich struktur z grupą karboksylową oraz wodoru.

The data are presented on gas components content in gas phase, formed during low-temperature oxidation (50, 70 and 90 C) of bituminous coals with 20% of oxygen in mixture with helium. Experiments were performed on 19 samples of bituminous coals, derived from 9 polish coal mines. Coals weathering and/or their low-temperature oxidation result in, among others, hydrogen formation. It has been proved that the hydrogen was not a gas constituent adsorbed or occluded in coal matrix in the bed. Equilibrium concentration of formed hydrogen is similar for all investigated coals and constitutes 0,5% vol. in post-reaction gas mixture occuring in the space of the applied reactor. It has been calculated that one ton of coal can produce in this way, about 70 L of molecular hydrogen. It was found, that source structures involved in hydrogen formation in the process are aliphatic and alicyclic coal structural units with double bonds. The units may be present as substituents or bridges of unsaturated chain hydrocarbons in coal macrostructure or partly aromatised alicyclic units possessing unsaturated ring, to which oxygen readily bounds and leads to formation of aldehydes. Strongly reactive structures possessing aldehyde group, in reaction with water vapour are forming molecular hydrogen and respective structures with carboxylic group.