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Background: Sugarcane distillery waste water (SDW) or vinasse is the residual liquid waste generated during sugarcane molasses fermentation and alcohol distillation. Worldwide, this effluent is responsible for serious environmental issues. In Reunion Island, between 100 and 200 thousand tons of SDW are produced each year by the three local distilleries. In this study, the potential of Aspergillus niger to reduce the pollution load of SDW and to produce interesting metabolites has been investigated., Results: The fungal biomass yield was 35 g L -1 corresponding to a yield of 0.47 g of biomass/g of vinasse without nutrient complementation. Analysis of sugar consumption indicated that mono-carbohydrates were initially released from residual polysaccharides and then gradually consumed until complete exhaustion. The high biomass yield likely arises from polysaccharides that are hydrolysed prior to be assimilated as monosaccharides and from organic acids and other complex compounds that provided additional C-sources for growth. Comparison of the size exclusion chromatography profiles of raw and pre-treated vinasse confirmed the conversion of humic- and/or phenolic-like molecules into protein-like metabolites. As a consequence, chemical oxygen demand of vinasse decreased by 53%. Interestingly, analysis of intracellular lipids of the biomass revealed high content in oleic acid and physical properties relevant for biodiesel application., Conclusions: The soft-rot fungus A. niger demonstrated a great ability to grow on vinasse and to degrade this complex and hostile medium. The high biomass production is accompanied by a utilization of carbon sources like residual carbohydrates, organic acids and more complex molecules such as melanoidins. We also showed that intracellular lipids from fungal biomass can efficiently be exploited into biodiesel.

Background: The so-called antikeratin antibodies and the antiperinuclear factor are the most specific serological markers of rheumatoid arthritis (RA). They were recently shown to be largely the same autoantibodies and to recognize human epidermal filaggrins and profilaggrin-related proteins of buccal epithelial cells (collectively referred to as (pro)filaggrin)., Materials and Methods: To further characterize the target antigens, we investigated their expression by normal human epidermal keratinocytes cultured in differentiating conditions, using immunofluorescence and immunoblotting with RA sera and three different monoclonal antibodies to (pro)filaggrin., Results: On the cornified, stratified epithelial sheets obtained in vitro, RA sera with anti(pro)filaggrin autoantibodies (AFA) produced granular staining of the stratum granulosum and diffuse staining of the stratum corneum. The antigens recognized by RA sera strictly colocalized with (pro)filaggrin in keratohyalin granules. Following sequential extraction of the proteins from the epithelial sheets, the RA sera and the three monoclonal antibodies to (pro)filaggrin, recognized a series of low-salt-soluble molecules, including a neutral/acidic isoform of filaggrin and several proteins with sizes and pI intermediates between this isoform and profilaggrin. They also recognized urea-soluble high-molecular-weight profilaggrin-related molecules., Conclusions: These results show that in vitro epidermal keratinocytes express various molecular forms of (pro) filaggrin that bear epitopes targeted by AFA of RA sera, and that some of these are absent from epidermis. Moreover, these epitopes, which are present on the keratohyalin granules of buccal epithelial cells but not on those of epidermal cells, are present on the granules of the cultured keratinocytes. This work completes the molecular characterization of the proteins targeted by AFA.