Biooxidation of hydrogen sulfide to sulfur by moderate thermophilic acidophilic bacteria.

The copper industry utilizes significant amounts of sulfuric acid in its processes, generating sulfate as waste. While sulfate-reducing bacteria can remove sulfate, it produces hydrogen sulfide (H2S) as a byproduct. This study examined the capability of a consortium consisting of Sulfobacillus thermosulfidooxidans and Sulfobacillus acidophilus to partially oxidize H2S to S° at a temperature of 45 °C. A fixed-bed bioreactor, with glass rings as support material and sodium thiosulfate as a model electron donor, was inoculated with the consortium. Formation of biofilms was crucial to maintain the bioreactor's steady state, despite high flow rates. Afterward, the electron donor was changed to H2S. When the bioreactor was operated continuously and with high aeration, H2S was fully oxidized to SO42-. However, under conditions of low aeration and at a concentration of 0.26 g/L of H2S, the consortium was able to oxidize H2S to S° with a 13% yield. S° was discovered attached to the glass rings and jarosite. The results indicate that the consortium could oxidize H2S to S° with a 13% yield under low aeration and at a concentration of 0.26 g/L of H2S. The findings highlight the capability of a Sulfobacillus consortium to convert H2S into S°, providing a potential solution for addressing environmental and safety issues associated with sulfate waste generated by the mining industry.

One step N-glycosylation by filamentous fungi biofilm in bioreactor of a new phosphodiesterase-3 inhibitor tetrazole.

An efficient and rapid process for N-glycosylation of 5-(1-(3-fluorophenyl)-1H-pyrazol-4-yl)-2H-tetrazole-LQFM 021 (1), a new synthetic derivative of pyrazole with phosphodiesterase-3 (PDE-3) inhibitory action, vasorelaxant activity and low toxicity catalyzed by filamentous fungi biofilm in bioreactor was successfully developed. A maximum N-glycosyl yield of 68% was obtained with Cunninghamella echinulata ATCC 9244 biofilm in bioreactor with conditions of 25mgml(-1) of 1 in PDSM medium at 28°C for 96h. After extraction with ethyl acetate, the derivative was identified by Ultrahigh Resolution Mass Spectrometry and (1)H-(13)C HSQC/HMBC.