31 research outputs found
Fermentation of deproteinized cheese whey powder solutions to ethanol by engineered Saccharomyces cerevisiae : effect of supplementation with corn steep liquor and repeated-batch operation with biomass recycling by flocculation
The lactose in cheese whey is an interesting
substrate for the production of bulk commodities such as
bio-ethanol, due to the large amounts of whey surplus
generated globally. In this work, we studied the performance
of a recombinant Saccharomyces cerevisiae strain
expressing the lactose permease and intracellular ß-galactosidase
from Kluyveromyces lactis in fermentations of
deproteinized concentrated cheese whey powder solutions.
Supplementation with 10 g/l of corn steep liquor significantly
enhanced whey fermentation, resulting in the production
of 7.4% (v/v) ethanol from 150 g/l initial lactose in
shake-flask fermentations, with a corresponding productivity
of 1.2 g/l/h. The flocculation capacity of the yeast
strain enabled stable operation of a repeated-batch process
in a 5.5-l air-lift bioreactor, with simple biomass recycling
by sedimentation of the yeast flocs. During five consecutive
batches, the average ethanol productivity was 0.65 g/l/h
and ethanol accumulated up to 8% (v/v) with lactose-toethanol
conversion yields over 80% of theoretical. Yeast
viability (>97%) and plasmid retention (>84%) remained
high throughout the operation, demonstrating the stability
and robustness of the strain. In addition, the easy and
inexpensive recycle of the yeast biomass for repeated utilization
makes this process economically attractive for
industrial implementation.Fundação para a Ciência e a Tecnologia (FCT)LACTOGAL-Produtos Alimentares S.A.Companhia Portuguesa de Amidos, S.A
Influence of antisynthetase antibodies specificities on antisynthetase syndrome clinical spectrum time course
Antisynthetase syndrome (ASSD) is a rare clinical condition that is characterized by the occurrence of a classic clinical triad, encompassing myositis, arthritis, and interstitial lung disease (ILD), along with specific autoantibodies that are addressed to different aminoacyl tRNA synthetases (ARS). Until now, it has been unknown whether the presence of a different ARS might affect the clinical presentation, evolution, and outcome of ASSD. In this study, we retrospectively recorded the time of onset, characteristics, clustering of triad findings, and survival of 828 ASSD patients (593 anti-Jo1, 95 anti-PL7, 84 anti-PL12, 38 anti-EJ, and 18 anti-OJ), referring to AENEAS (American and European NEtwork of Antisynthetase Syndrome) collaborative group's cohort. Comparisons were performed first between all ARS cases and then, in the case of significance, while using anti-Jo1 positive patients as the reference group. The characteristics of triad findings were similar and the onset mainly began with a single triad finding in all groups despite some differences in overall prevalence. The "ex-novo" occurrence of triad findings was only reduced in the anti-PL12-positive cohort, however, it occurred in a clinically relevant percentage of patients (30%). Moreover, survival was not influenced by the underlying anti-aminoacyl tRNA synthetase antibodies' positivity, which confirmed that antisynthetase syndrome is a heterogeneous condition and that antibody specificity only partially influences the clinical presentation and evolution of this condition