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21.
The ability of Trametes versicolor and Pleurotus ostreatus to grow on agroindustrial wastes, such as orange peels, and to degrade model polycyclic aromatic hydrocarbons (PAHs) in solid‐state fermentation (SSF) was evaluated. Best results in laccase production were obtained with T. versicolor cultures (3000 U L?1), however, P. ostreatus (2700 U L?1) showed higher ability to degrade the tested PAHs phenanthrene (PHE) and pyrene (PYR). Moreover, orange peels can be used as biofertilizer and the oxidative ability of the spent fungus and substrate obtained in SSF can be used in the remediation of polluted soil. The results obtained confirm this hypothesis. Thus, the decontamination achieved in soils polluted with PYR was around 43% (after 30 days) by addition of spent fungus and substrate from SSF.  相似文献   
22.
Stable isotope and trace element analyses of 230 Jurassic (Pliensbachian–Toarcian) samples from northern Spain have been performed to test the use of geochemical variations in fossils (belemnites and brachiopods) and whole‐rock hemipelagic carbonates as palaeoceanographic indicators. Although the succession analysed (Reinosa area, westernmost Basque–Cantabrian Basin) has been subject to severe thermal alteration during burial diagenesis, the samples appear to be well preserved. The degree of diagenetic alteration of the samples has been assessed through the application of integrated petrographic, chemical and cathodoluminescence analyses. It is demonstrated that brachiopods and whole‐rock carbonates, although widely used for palaeoceanic studies, do not retain their primary marine geochemical composition after burial diagenesis. In contrast, there is strong evidence that belemnite rostra preserve original isotopic values despite pervasive diagenesis of the host rock. Well‐preserved belemnite shells (non‐luminescent to slightly luminescent) typically show stable isotope values of +4·3‰ to –0·7‰δ13C, +0·7‰ to –3·2‰δ18O, and trace element contents of <32 μg g–1 Mn, <250 μg g–1 Fe, >950 μg g–1 Sr and Sr/Mn ratios >80. This study suggests that the degree to which diagenesis has affected the preservation of an original isotopic composition may differ for different low‐Mg calcite fossil shells and hemipelagic bulk carbonates, behaviour that should be considered when marine isotopic signatures from other ancient carbonate rocks are investigated. Multiple non‐luminescent contemporaneous belemnite samples passed the petrographic and geochemical tests to be considered as palaeoceanic recorders, yet their δ13C and δ18O values exhibited moderate scatter. Such variability is likely to be related to the palaeoecological behaviour of belemnites and/or high‐frequency secular variations in sea‐water chemistry superimposed on the long‐term isotopic trend. A pronounced positive carbon‐isotope excursion (up to +4·3‰) is documented in the early Toarcian serpentinus biozone, which correlates with the Toarcian δ13C maximum reported in other European and Tethyan regions.  相似文献   
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