Specjacja glinu w wodzie i osadzie dennym stawów rybno-hodowlanych

Water and bottom sediment samples collected from a few fish-breeding ponds/reservoirs were subjected to tests. The aim of this paper was to determine the total content of aluminium and its fractions in the samples tested to estimate the potential risk to fish caused by the toxic forms of aluminium. The monomeric inorganic aluminium in waters was determined using the ion exchange and extraction-colorimetric method with oxychinoline according to Barnes's-Driscoll's procedure. The bottoms were fractionated using a three-step sequential extraction procedure and the microwave mineralisation. The total content of aluminium in waters and extracts was determined using the spectrophotometric method with eriochromocyanine R, and comparatively using the ICP OES technique. The results were subjected to statistical analysis. The level of concentration of labile Al in the waters about 26-34 ?g/dm3 and content of exchangeable Al 5-34 mg/g range in bottom sediments are possibly hazardous to aquatic organisms.Badaniom poddano próbki wody i osadu dennego pobrane z kilku stawów rybnych. Oznaczono całkowitą zawartość oraz frakcje glinu w badanych próbkach. Glin monomeryczny nieorganiczny wyznaczono metodą wymiany jonowej i ekstrakcyjno-kolorymetryczną z zastosowaniem oksychinoliny według procedury Barnes'a-Driscoll'a. Frakcjonowanie osadów dennych wykonano procedurą ekstrakcji sekwencyjnej Tessier'a w wersji ujednoliconej oraz z zastosowaniem mineralizacji mikrofalowej. Glin całkowity w wodzie oraz w ekstraktach oznaczono metodą spektrofotometryczną z eriochromocyjaniną R, porównawczo techniką ICP OES i dokonano oceny statystycznej otrzymanych wyników. Poziom stężenia glinu labilnego w wodach: 26-34 ?g/dm3 oraz glinu wymiennego i kwasowego w osadach: 5-34 mg/g nie wskazuje na zagrożenie dla hodowli ryb pod warunkiem, że zachowana będzie kwasowość wody. Przy pH = 4,3 następuje znaczny wzrost stężenia wszystkich oznaczanych form glinu, w tym również najbardziej toksycznego dla ryb - glinu monomerycznego nieorganicznego (Ali), którego stężenie zwiększa się ponad 10-krotnie w porównaniu do wód o odczynie pH = 7,1-8,2

Exchangeable and Bioavailable Aluminium in the Mountain Forest Soil of Barania Góra Range (Silesian Beskids, Poland)

The research was carried out in the spruce forests of Barania Góra (Silesian Beskids, Poland) affected by pandemic dying of trees. Twenty-seven samples were collected from the O layer in two plots: 17 in a cut down forest infested with insect pests (bark beetle) and ten in a 120-year-old healthy forest. The analyses covered basic parameters (pHH2O, pHKCl, worg, Ctot, Ntot, CEC) and the concentrations of aluminium in the fractions leached with 0.1 M BaCl2 (Alexch), 0.5 M CuCl2 and 0.1 M Na4P2O7 (Albio) solutions. The total aluminium concentration in the soil was assayed digesting samples with hydrofluoric acid. The effect of pH and organic matter content on the amount of exchangeable (Alexch) and bioavailable (Alexch) aluminium in the soil was analysed. It has been found that the soils in both plots are strongly acidic and contain 550 to 1,700 mg kg−1 of exchangeable aluminium and 1,200 to 4,800 mg kg−1 of bioavailable aluminium. The lack of disease symptoms in the spruce trees in plot 2 can be explained by the higher content of organic matter in the soil. Unfortunately, one might expect that the high concentration of exchangeable aluminium will also cause the trees in the area to wither

Conversion of squid pens to chitosanases and dye adsorbents via Bacillus cereus

[[abstract]]The purpose of this study was to reclaim squid pens for the production of chitosanases and biosorbents of food colorants and industrial dyes via Bacillus cereus fermentation. B. cereus TKU044 produced chitosanases at a high productivity of 2.66 U/mL, when squid pens were used as the sole carbon and nitrogen source. An extracellular chitosanase, with a molecular weight of 43 kDa, was purified 286-fold with a 16% activity yield. TKU044 and five other chitosanaseproducing strains of B. cereus have been used as biosorbents to investigate their adsorption capacity on 0.025% (w/v) of colorants and dyes. For colorants, only Red 7 was adsorbed by the five B. cereus cells, whereas all tested B. cereus strains showed adsorption effects with the dyes. The adsorption of Yellow 4 by squid pens before and after 1 day of fermentation by B. cereus was also studied.[[sponsorship]]科技部[[notice]]補正完