Vergleich bodenbiologischer Eigenschaften ökologischer und konventioneller Praxisflächen: Integration der Forschung in reguläre Lehrveranstaltungen

Organic agriculture (OA) soils have often been shown to have a higher soil microbial biomass (SMB), microbial activity (MA) and a higher soil organic matter (SOM) content than conventional soils. The objectives of this study were to assess the soil fertility of an organically and a conventionally managed field and to ascertain whether BSc students of the study program “Sustainable Agriculture” could assist in regular soil biological field measurements to monitor the effect of farming systems on soil health. Soil samples from both sites were analysed for SOM, pH, water holding capacity, SMB and MA. The results confirmed previous findings of a higher MA, a larger SMB and a higher SOM content under OA. In contrast to other results, the microbial quotient was low whereas the metabolic quotient was high in both soils, indicating low substrate availability and stress. The variability of the data produced by the students was within the range typical of soil biological measurements, showing that BSc students can already be involved in soil biological research

Enhanced production yields of rVSV-SARS-CoV-2 vaccine using Fibra-Cel® macrocarriers

The COVID-19 pandemic has led to high global demand for vaccines to safeguard public health. To that end, our institute has developed a recombinant viral vector vaccine utilizing a modified vesicular stomatitis virus (VSV) construct, wherein the G protein of VSV is replaced with the spike protein of SARS-CoV-2 (rVSV-ΔG-spike). Previous studies have demonstrated the production of a VSV-based vaccine in Vero cells adsorbed on Cytodex 1 microcarriers or in suspension. However, the titers were limited by both the carrier surface area and shear forces. Here, we describe the development of a bioprocess for rVSV-ΔG-spike production in serum-free Vero cells using porous Fibra-Cel® macrocarriers in fixed-bed BioBLU®320 5p bioreactors, leading to high-end titers. We identified core factors that significantly improved virus production, such as the kinetics of virus production, the use of macrospargers for oxygen supply, and medium replenishment. Implementing these parameters, among others, in a series of GMP production processes improved the titer yields by at least two orders of magnitude (2e9 PFU/mL) over previously reported values. The developed process was highly effective, repeatable, and robust, creating potent and genetically stable vaccine viruses and introducing new opportunities for application in other viral vaccine platforms