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EN
Background: Volcanic ash, which is ejected during volcanic eruptions, flies in the air and spreads by the wind over large distances. It is a magmatic source and as such may contain heavy metals. The aim of the study was to carry out investigation on heavy metal content: Pb, Cd, Zn, Fe, Mn, Cu and Cr in samples of moss bags exposed to atmospheric dust containing volcanic ash in Sosnowiec (Poland) after eruption of Eyjafjallajökull volcano in Iceland. Materials and methods: Samples have been exposed to atmospheric dust after volcanic eruption for 2 months, and were mineralised in 70% HNO3 and 30% H2O2. The content of Pb and Cd was analysed by atomic absorption spectrometry with electrothermal atomization (ETAAS) and Zn, Fe, Mn, Cu, Cr by atomic absorption spectrometry with flame atomization (FAAS). Results: During the experiment the content of lead in samples of moss increased by 54,9 μg/g, cadmium by 3,41 μg/g, manganese by 150 μg/g, iron by 6,09 mg/g, zinc by 514 μg/g, copper by 20,77 μg/g and chromium by 6,99 μg/g. Conclusions: In Sosnowiec the comparable increase of metal content was from several to 41 times higher than in the areas not exposed to volcanic ash. It indicates that volcanic ash can be a potential source of heavy metals in the environment and, consequently, affect our health.
PL
Wstęp: Pył atmosferyczny, który jest wyrzucany podczas erupcji wulkanów, długo unosi się w powietrzu i rozprzestrzenia na duże odległości przy udziale wiatru. Jest pochodzenia magmowego, więc może zawierać metale ciężkie. Celem pracy było zbadanie zawartości metali ciężkich: Pb, Cd, Zn, Fe, Mn, Cu i Cr w próbkach mchu narażonych na działanie pyłu wulkanicznego opadającego na ziemię. Materiał i metody: Mchy były wystawione na działanie pyłu atmosferycznego po erupcji wulkanu przez }2 miesiące. Próby były mineralizowane kwasem azotowym i nadtlenkiem wodoru. Zawartość Pb i Cd oznaczono za pomocą absorpcyjnej spektrometrii atomowej z elektrotermiczną atomizacją, a Zn, Fe, Mn, Cu i Cr za pomocą absorpcyjnej spektrometrii atomowej z atomizacją w płomieniu. Wyniki badań: Podczas przeprowadzenia doświadczenia zawartość ołowiu w mchach zwiększyła się o 54,9 μg/g, Cd o 3,41 μg/g, Mn o 150 μg/g, Fe o 6,09 mg/g, Zn o 514 μg/g, Cu o 20,77 μg/g oraz Cr o 6,99 μg/g. Wnioski: W Sosnowcu stwierdzono od kilku do kilkudziestu razy wyższe przyrosty zawartości oznaczanych metali niż w porównywanych miejscach, co wskazuje, iż pył wulkaniczny może być potencjalnym źródłem metali ciężkich w środowisku, a w konsekwencji wpływać na nasze zdrowie.
2
Content available remote A novel α-glucosidase from the moss Scopelophila cataractae
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EN
Scopelophila cataractae is a rare moss that grows on copper-containing soils. S. cataractae protonema was grown on basal MS medium containing copper. A starch-degrading activity was detected in homogenates of the protonema, after successive extraction with phosphate buffer and buffer containing 3 M LiCl. Buffer-soluble extract (BS) and LiCl-soluble extract (LS) readily hydrolyzed amylopectin to liberate only glucose, which shows that α-glucosidase (EC 3.2.1.20) in BS and LS hydrolyzed amylopectin. The Km value of BS for maltose was 0.427. The Km value of BS for malto-oligosaccharide decreased with an increase in the molecular mass of the substrate. The value for maltohexaose was 0.106, which is about four-fold lower than that for maltose. BS was divided into two fractions of α-glucosidase (BS-1 and BS-2) by isoelectric focusing. The isoelectric points of these two enzymes were determined to be 4.36 (BS-1) and 5.25 (BS-2) by analytical gel electrofocusing. The two enzymes readily hydrolyzed malto-oligosaccharides. The two enzymes also hydrolyzed amylose, amylopectin and soluble starch at a rate similar to that with maltose. The two enzymes readily hydrolyzed panose to liberate glucose and maltose (1 : 1), and the Km value of BS for panose was similar to that for maltotriose, whereas the enzymes hydrolyzed isomaltose only weakly. With regard to substrate specificity, the two enzymes in BS are novel α-glucosidases. The two enzymes also hydrolyzed β-limit dextrin, which has many α-1,6-glucosidic linkages near the non-reducing ends, more strongly than maltose, which shows that they do not need a debranching enzyme for starch digestion. The starch-degrading activity of BS was not inhibited by p-chloromercuribenzoic acid or α-amylase inhibitor. When amylopectin was treated with BS and LS in phosphate buffer, pH 6.0, glucose, but not glucose-1-phosphate, was detected, showing that the extracts did not contain phosphorylase but did contain an α-glucosidase. These results show that α-glucosidases should be capable of complete starch digestion by themselves in cells of S. cataractae.
EN
Pylaisia polyantha moss growing near intensive traffic in Geležinis Vilkas street at Vingis Park (Vilnius) was selected as an indicator of environmental pollution. Two models were applied for the study: the Gaussian plume model – for zinc emission from automobiles calculation and mathematical model – for recalculating the zinc emission from transport to zinc concentration in moss. Moss samples were collected during spring, summer and autumn. There were no significant changes in Zn concentrations between these periods. Zn emission dispersion from pollution source was calculated only for one vehicle, in order to reach relationships between environmental conditions and dispersion of Zn emission from vehicle exhaust fumes pipe. It was detected that the concentration of Zn tends to decrease with the distance from the pollution source. It was observed that there was a strong relationship between wind speed and Zn concentration – the slower the wind speed, the higher concentration of zinc in moss.
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