Evaluation of microorganisms with sulfidogenic metabolic potential under anaerobic conditions

The aim of this work was to identify groups of microorganisms that are capable of degrading organic matter utilizing sulfate as an electron acceptor. The assay applied for this purpose consisted of running batch reactors and monitoring lactate consumption, sulfate reduction and sulfide production. A portion of the lactate added to the batch reactors was consumed, and the remainder was converted into acetic, propionic and butyric acid after 111 hours of operation These results indicate the presence of sulfate-reducing bacteria (SRB) catalyzing both complete and incomplete oxidation of organic substrates. The sulfate removal efficiency was 49.5% after 1335 hours of operation under an initial sulfate concentration of 1123 mg/L. The SRB concentrations determined by the most probable number (MPN) method were 9.0x10(7) cells/mL at the beginning of the assay and 8.0x10(5) cells/mL after 738 hours of operation

Recent Advances in Sugarcane Industry Solid By-Products Valorization

Sugarcane is among the leading agricultural crop cultivated in tropical regions of the world. Industrial processing of sugarcane generates sugar; as well as various solid wastes (i.e. sugarcane bagasse, pressmud). Improvement of biotechnology in industrial level, offers opportunities for economic utilization of these solid residues. In the last few decades, sugarcane bagasse and pressmud have been explored in the theme of lignocellulosic bioconversion. The recalcitrance of biomass is a major drawback towards successful exploitation of lignocellulosic residues. Pretreatment by suitable/efficient processes can overcome this limitation. In this regards; physical, chemical and biological treatment systems are brought into our perspective. Chemical and physicochemical methods are capital-intensive but not environment-friendly, in contrast, method like biological treatment is eco-friendly but extremely slow. There are still major technological and economic challenges need to be addressed; e.g. bioprospecting, established more reliable genetically modified microorganisms, upgrade gene cloning and sequencing processes, yield improvement at large scale etc. Productions of value-added products from these solid wastes are discussed in such a way that pinpoints the most recent trends and the future directions. Biofuels, enzymes, organic acids and bio-sorbents production draw a clear sketch of the current and future bio-based products. Nano-biotechnology and genetic engineering could be future trends to improved processes and products. This review serves as a valuable reference material for a wide range of scientists and technologists in the relevant fields