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Abstract Intrinsic water-use efficiency (iWUE) of trees is an important component of the Earth’s coupled carbon and water cycles. The causes and consequences of long-term changes in iWUE are, however, still poorly understood due to the complex interplay between biotic and abiotic factors. Inspired by the role calcium (Ca) plays in plant transpiration, we explore possible linkages between tree ring-derived iWUE and Ca availability in five central European forest sites that were affected by acidic air pollution. We show that increasing iWUE was directly modulated by acid air pollution in conjunction with soil Ca concentration. Responses of iWUE to rising atmospheric CO2 concentrations accelerated across sites where Ca availability decreased due to soil acidity constraints, regardless of nitrogen and phosphorus availability. The observed association between soil acidity, Ca uptake, and transpiration suggests that Ca biogeochemistry has important, yet unrecognized, implications for the plant physiological upregulation of carbon and water cycles.

Hydrophobins produced by the Fusarium genus in brewing barley in connection with gushing phenomenon have been studied in many different countries. However, the presence of proteins associated with gushing in grains harvested in Brazil is currently unknown. The surface active class 2 hydrophobin Hyd5 has been identified as a possible causative agent for gushing of beer. For this reason, the objective of this study was to evaluate the presence of Hyd5 in isolated Fusarium strains from Brazilian barley samples. This was followed by gushing tests. The Hyd5 gene was identified in all fungal isolates and phylogenetic analysis exhibited four main linages. Gushing tests demonstrated that among the 21 analysed malt samples 8 were positive considering overfoaming at the bottle opening. Levels ranged from 8 to 124 g/bottle of gushing. No correlation between phylogenetic analysis and gushing was observed when they were evaluated together. This is due to positive isolates for gushing which are scattered throughout the phylogenetic tree. The other cause may be that all main clades contain at least one positive isolate for gushing. More research regarding hydrophobins and gushing should be carried out in the future due to the fungi isolated in Brazilian samples. These results offer excellent support that could help the brewing industry to prevent its losses and to provide further understanding of the gushing phenomenon in beer.

The increasing interest in defining the content of mycotoxins is related to the development of methods for their determination. Several methods of determination have been published. This paper describes analytical procedures such as (a) sample preparation – sampling and homogenization, (b) extraction and purification – solid phase extraction (SPE), a QuEChERS method (acronymic name from quick, easy, cheap, effective, rugged and safe), solid-liquid extraction (SLE) and immuno affinity extraction (IAE). It also provides a review of, (c) instruments, and other analytical methods such as thin layer chromatography (TLC), enzyme linked immune sorbent assay (ELISA) and liquid chromatography (LC), gas chromatography (GC) with different detectors for determination of mycotoxin in barley, malt and beer are discussed.

Mycotoxins are widely studied by many research groups in all aspects, but the stability of these compounds needs further research for clarification. The objective of this study is to evaluate deoxynivalenol and zearalenone stability during all steps of the malting and brewing processes. The levels of these compounds decreased significantly during the production process (barley to beer). During the malting process, the DON levels decreased significantly in the steeping, germination, and malting steps (62%, 51.5%, and 68%, respectively). Considering ZEN, when the levels were compared between barley and the last step of the process, a significant decrease was observed. Most of the mycotoxins produced were transferred to the rootlets and spent grains, which is advantageous considering the final product. Furthermore, the mycotoxin dietary intake estimation was included in this study. The results proved that if the concentrations of target mycotoxins in raw material are under the limits established by the regulations, the levels decrease during the malting and brewing processes and make the beer secure for consumers. The quality of the five commodities involved in the beer process plays a decisive role in the creation of a safe final product.

In 2009-2012, the occurrence of mycotoxin deoxynivalenol in beer samples from Czech outlet shops was monitored . Samples included pale, dark, dispensed, lager and non-alcoholic beers . Deoxynivalenol content was analyzed by the liquid chromatography method with mass spectrometric detection . Deoxynivalenol was detected in 74 .8 % of the analyzed beers, its content ranged from 2 .0-44 .0 μg/l . Mean deoxynivalenol content in all samples in relation to the year of the occurrence moved from 4 .3-8 .3 μg/l .In 2009-2012, the occurrence of mycotoxin deoxynivalenol in beer samples from Czech outlet shops was monitored . Samples included pale, dark, dispensed, lager and non-alcoholic beers . Deoxynivalenol content was analyzed by the liquid chromatography method with mass spectrometric detection . Deoxynivalenol was detected in 74 .8 % of the analyzed beers, its content ranged from 2 .0-44 .0 μg/l . Mean deoxynivalenol content in all samples in relation to the year of the occurrence moved from 4 .3-8 .3 μg/l .