Abstract: The present application relates to a process for removing hydrogen sulfide H2S from a gas (1) by contacting said gas with a liquid solution (2) containing ferric sulfate in an absorption column (RC). Ferric sulfate and H2S react at room temperature and at a pressure ranging from 1 to 1.2 atm. Ferric ions being reduced to two-valent iron and sulfide oxidised to elemental sulfur. The liquid (4) coming out of the absorption column is filtered in two steps, the retentate (6, 8) comprising elemental sulfur, the filtrate (5, 7) containing the iron ions. The filtrate is sent to a bioreactor (RB) for regeneration, i.e. oxidation of iron to Fe3+ by means of thiobacillus ferroxidans and air injection (10). The regenerated solution is reused in the absorption column (RC). The process faces the problems relating to the alignment between the chemical step and the biological step in order to obtain a process which can stably run continuously.

Abstract: The present application relates to a process for removing hydrogen sulfide H2S from a gas (1) by contacting said gas with a liquid solution (2) containing ferric sulfate in an absorption column (RC). Ferric sulfate and H2S react at room temperature and at a pressure ranging from 1 to 1.2 atm. Ferric ions being reduced to two-valent iron and sulfide oxidised to elemental sulfur. The liquid (4) coming out of the absorption column is filtered in two steps, the retentate (6, 8) comprising elemental sulfur, the filtrate (5, 7) containing the iron ions. The filtrate is sent to a bioreactor (RB) for regeneration, i.e. oxidation of iron to Fe3+ by means of thiobacillus ferroxidans and air injection (10). The regenerated solution is reused in the absorption column (RC). The process faces the problems relating to the alignment between the chemical step and the biological step in order to obtain a process which can stably run continuously.

Abstract: The invention relates to a strain of Arthrobacter sp. CBS 208.96 capable of selectively effecting the opening of the C-S bond of sulfurated organic molecules present in carbonaceous materials and its use in a process for the selective removal of organic sulfur from fossil fuels contained therein.

Abstract: The mutants of neutral protease (NP) described can retain their enzymatic activities at temperatures at which wild-type neutral protease becomes inactive, the mutants being characterised in that the Gly 189 and/or Gly 147 residues of the aminoacid sequence of NP are replaced by different residues selected from the natural aminoacids.Mutagenised genes of neutral protease which code for the mutants, recombinant plasmids containing the genes, and strains of Bacillus transformed by the plasmids are also described. The mutants of neutral protease having the characteristics described above are particularly useful in the food sector.

Abstract: An enzyme system for hydrolysis of protein material from plant and animal sources is obtained by extracting germinated sorghum seeds. The enzyme system contains a proteolytic component active on intact proteins and large peptides at an optimum pH of 3.2 to 4.2 and a peptidase component active on small peptides at an optimum pH of 4.5 to 6.5. A protein hydrolyzate having an average molecular weight within a selected range can be obtained by varying the pH so as to depress activity of the proteolytic component or the peptidase component. The protein hydrolysates which are obtained are characterized by the absence of bitter taste. Furthermore, by suitably adjusting the enzyme concentration in the reaction medium, the temperature and the hydrolysis time, protein hydrolyzates with an average molecular weight lower than 700 and a low percentage of free amino acids can be obtained.

Abstract: Phenylalanine level in blood or another medium is considerably reduced and can even be annulled by causing blood or the other medium to flow through a mass of porous fibers in which the enzyme phenylalanine ammonia lyase has been occluded: the fibers have been previously made biocompatible, if necessary.