Latest SCI publications
RIVAR - A quantitative concept to study human-derived antibiotic resistance in rivers along the human wastewater path
Research project (§ 26 & § 27)
Duration : 2020-03-01 - 2023-02-28
The rise in antimicrobial resistances is a global threat to human health. Apart from hospitals, where multi-resistant bacteria pose an acute problem, the spread of human-derived antibiotic resistant bacteria (ARB) and resistance genes (ARG) from wastewater treatment plants (WWTPs) into river ecosystems is of growing concern as river water is used for a variety of purposes (drinking water production, recreation, irrigation). Although an increasing number of studies have been published in recent years demonstrating the presence of human-derived ARB and ARG in rivers, no comprehensive quantitative concept exists that describes and explains the distribution patterns, and driving factors of human-derived ARB and ARG in these environments. For this project, a new quantitative concept was developed to study the distribution patterns, propagation pathways and driving factors of human-derived ARB and ARG along four rivers in Lower Austria exhibiting gradients in river size, land use, fecal pollution, hospital wastewater and potential co-selection factors. The following hypotheses shall be tested: (1) In water, human-derived ARB and ARG abundances are coupled to the extent of fecal pollution from WWTPs and to the extent of wastewater input from hospitals. This coupling is independent from the longitudinal development of the river. (2) In biofilms, human-derived ARB and ARG abundances can be uncoupled from the extent of fecal pollution and from hospital wastewater input. In the presence of specific ecological selection factors such as metals or pesticides, an amplification of ARB and ARG occurs. The new concept is based on the quantification of human-derived ARB and ARG in specific bacterial targets, determined in water and biofilms by a combined cultivation and DNA-based approach. This information will be linked with quantitative data on the extent and sources of fecal pollution (following the human wastewater path) and with a comprehensive assessment of the environmental conditions. This study will stimulate new ideas to understand and manage microbial water quality and antibiotic resistance in rivers. At the global level, the proposal is directly addressing the fundamental requirements of the research agenda defined for water, sanitation and antimicrobial resistance (AMR) of the WHO Global Action Plan for AMR. At the uropean level it directly addresses the concrete action plan to close knowledge gaps on AMR within the EU AMR Action Plan. At the local level, it directly contributes to the prioritised research area “Organic trace substances” within the “Water” topic of the recent FTI strategy for Lower Austria. Sustainable collaborations will be stimulated between the project partners of the ICC Water & Health at KL Krems, of the department IFA-Tulln of the University of Natural Resources and Life Sciences, Vienna and of the Medical University Graz. By this, the project will contribute in a sustainable manner to the welfare of Lower Austria and beyond.
Research project (§ 26 & § 27)
Duration : 2020-01-01 - 2022-12-31
Fumonisins are produced by various Fusarium (and Aspergillus) spp. and are often occurring on maize and maize products. They are potent renal toxins, cancer promoters and cause birth defects. Maximum (or guidance) levels in food (and feed) have been set by authorities worldwide, but unaltered mycotoxins are not the only source of exposure for consumers. Fumonisins are prone to be non-covalently bound with proteins and complex carbohydrates. In addition, next to nothing is known about covalently bound fumonisins or about the natural occurrence of (potential) fumonisin metabolites other than their hydrolysed forms. Currently there is a lack of knowledge in the understanding how fumonisins interact with plants in in which form they are incorporated and carried over in food. In their recent report from 2018, the Joint FAO/WHO Expert Committee on Food Additives (JECFA) specifically recommends that “studies should be conducted to better understand the occurrence of bound fumonisins … and their bioavailability after consumption”. To the best of our knowledge this is the first study worldwide that systematically aims to answer the questions raised above and therefore to significantly contribute to the risk assessment of these food contaminants.
Research project (§ 26 & § 27)
Duration : 2019-07-01 - 2020-12-31
A major task is the establishment of defined conditions for cultivation of several species of mealworms (larvae of darkling beetles, Tenebrionidae) allowing the study of mechanisms of mycotoxin metabolism. The goal of WP 1 (at BOKU-DAGZ) is to produce axenic mealworms in order to determine whether or not the microbiome provides a major contribution to mycotoxin detoxification. In WP 2 experiments with the 13C-labelled toxins deoxynivalenol, zearalenone and aflatoxin B1 will be performed. Prior to application of the expensive labelled toxins it will be critical to find conditions where the mycotoxins are reproducibly consumed by the mealworms. In case uptake by feed is insufficient, toxins will be directly injected into the insect’s abdominal tract, for subsequent analysis by LC-HRMS(/MS) and MetExtract. At the Center for Analytical Chemistry at IFA-Tulln it will also be determined how much of the intake can be explained by known metabolites. First pilot experiments and literature reports indicate that about up to 90% of deoxynivalenol remain unaccounted. Using the isotope-assisted LC-HRMS(/MS) workflow and MetExtract data processing it should be possible to find new derivatives, and to assign sum formulas and tentative structures to the detected derivatives of the parent toxins. This should allow to postulate biochemical reactions and corresponding enzymes catalyzing the formation of mycotoxin metabolites. Utilizing the fully sequenced genome of Tribolium castaneum (rice flour beetle) it should be possible to identify candidate genes, which in the remaining project time will be tested by heterologous expression. There is preliminary evidence that detoxification may be inducible in mealworms. Therefore, the main task of the WP 3 at the FH Tulln is to use proteomics methods to search for differences in the proteome of mealworms raised on toxin free compared to artificially contaminated feed, and to determine by peptide sequencing which genes may be responsible for the differentially formed proteins.