Patents Available Miscellaneous

Abstract: A process for the preparation of peroxycarboxylic acid of general formula R-COOOH, wherein R is an organic residue, in particular a linear or branched alkyl group, an aryl group or an alkyl aryl group each of which is optionally substituted with one or more groups, the process comprising treating a carboxylic acid of the general formula R-COOH, wherein R has the meaning indicated above, with hydrogen peroxide or a precursor thereof in the presence of an enzyme catalyst is claimed. The enzyme catalyst is preferably a hydrolase, such as a protease or a lipase. Also, a process for the oxidation of organic compounds with the peroxycarboxylic acids thus prepared is described.   

Detailed Description:  Peroxycarboxylic acids are commonly employed as oxidizing reagents in the field of organic synthesis for the production of organic chemicals. A wide variety of organic molecules may be oxidized by means of these reagents that, for instance, are useful for the preparation of epoxides from unsaturated hydrocarbons. Some peroxycarboxylic acids such as meta-chloro-peroxybenzoic acid have become commercially available as a result of their wide applicability.

 

Even though some peroxycarboxylic acids are useful and commercially available reagen ts their use is limited because of their relatively high cost and the risks (in particular the explosion hazard) involved in handling the reagents, especially when this is done on a large scale. Accordingly, there is a need for improved methods of preparing peroxycarboxylic acids as well as for methods that make it safer to use them in organic synthesis.

 

The present invention provides a safe and simple method for preparing peroxycarboxylic acids in situ by treating carboxylic acids with hydrogen peroxide in the presence of an enzyme as illustrated below. This method of preparing peroxycarboxylic acids presents a safe and economically viable approach for the preparation of these highly useful reagents. Furthermore, enzymatic synthesis of peroxycarboxylic acids and oxidation of organic chemicals by means of peroxycarboxylic acids may be carried out simultaneously. 

BE 491782, DE 690053096, FR 491782,  
GB 491782, JP 3080238, NL  491782,  
SE 491782, US 5541092  

 

 

Abstract: The invention relates to a process for converting peroxycar- boxylic acids to carboxylic acids, the process comprising treating a peroxycarboxylic acid of the general formula: R-CO-OOH wherein R is a linear or branched alkyl group, an aryl group or an aryl-alkyl group each of which may optionally be substituted with one or more hydroxy, halogen, alkoxy, amino, alkylamino, sulfo, sulfoxy, sulfono, amido, carboxy, percarboxy or nitro groups, with an enzyme catalyst to form the corresponding car- boxylic acid of the general formu la: R-CO-OH, wherein R has the meaning indicated above.

Detailed Description:  Peroxycarboxylic acids constitute an important class of substances that may be used for a wide range of purposes. Thus, peroxycarboxylic acids are commonly employed as oxidizing reagents in the field of organic synthesis for the production of a variety of organic chemicals. Apart from their use as oxidation reagents, peroxycarboxylic acids may also be used as bleaching agents, for instance to decolourize paper mill process streams. Furthermore, preparations of peroxycarboxylic acids are used for disinfection purposes (e.g. in the food industry) due to the sensitivity of microorganisms to these compounds.

 

While peroxycarboxylic acids are highly advantageous reagents for these and other applications, their continued presence in the end products is not always desirable as they represent a potential environmental or health hazard. For instance, solutions of dyes decolourized by means of peroxycarboxylic acids should preferably be free from remaining peroxycarboxylic acid before being discharged into the environment where the peroxycarboxylic acid might exert a harmful effect. Similarly, utensils and surfaces disinfected in the food industry by means of peroxycarboxylic acids should be free from the reagent prior to use since the peroxycarboxylic acid may otherwise deteriorate the food product produced or eventually reach the consumer. Furthermore, substances prepared by chemical synthesis utilizing peroxycarboxylic acids should be free from the oxidation reagent that might undesirably influence the further use or conversion of the synthesized substance. Accordingly, there is a need for processes whereby residual peroxycarboxylic acids may be removed, in particular processes which allow for selective decomposition of peroxycarboxylic acids under mild conditions.

 

The present invention provides a simple enzymatic process for degrading peroxycarboxylic acids selectively under very mild conditions. Accordingly, enzymes catalyse the conversion of peroxycarboxylic acids to the corresponding carboxylic acids. Such enzymatic processes permit selective transformation of peroxycarboxylic acids under mild conditions and provide an economical way of removing peroxycarboxylic acids from large volumes of dilute solutions of the peroxycarboxylic acids.

Patent References
Patent Number: 

AT 110416, BE 521951, DE 69103626.8,  
DK 521951, ES 521951, FR 521951  
GB 521951, IT 521951, NL 521951, US 5534435  

 

 

 

Abstract: A process for enzymatic degradation of sulfonylurea compounds, preferably sulfonylurea herbicides, and the use of the process for degradation and removal of herbicides from agricultural field spraying devices.    
Detailed Description:  Sulfonyl-urea based compounds are known to the art as powerful inhibitors of amino acid biosynthesis, which thus may be used to inhibit the proliferation of cells or organisms or even kill them. In the agricultural and horticultural area sulfonyl-urea based compounds, such as Tribenuron™ and Metsulforon™  are, inter alia, known as highly potent herbicides. Although the high amino acid biosynthesis inhibiting effect of these compounds allows for a desired general reduction in the load on the locus to which it is administered, these compounds may however by nature be harmful to other biological entities if contaminated.

 

The high amino acid biosynthesis inhibiting effect of sulfonyl-urea based compounds makes it critical to avoid that even trace amounts of the active compounds contaminate biological material where the compounds may have a harmful effect. Thus it is highly desired to reduce the risk of contamination, by reducing amino acid biosynthesis inhibiting effect of remaining amounts of sulfonyl-urea based compounds present e.g. in devices which is used both to administer these compounds to the intended biological locus and to loci where even trace amounts of the sulfonyl-urea based compounds have a harmful effect.

 

We have found that the amino acid biosynthesis inhibiting effect of sulfonyl-urea based compounds may be reduced or even eliminated by treating these compounds with an enzyme. Accordingly we have found a method for reducing amino acid biosynthesis inhibiting effect of a sulfonyl-urea based compound of the general formula:comprising contacting in an aqueous solution said sulfonyl-urea based compound with an enzyme.

 

 

 

Abstract: This technology provides a method for the extracellular production of heme proteins in filamentous fungi in yields which far exceed those obtainable for the same protein in yeast. Accordingly, the the method comprises a)  transforming a suitable filamentous fungus with a recombinant DNA vector which comprises a DNA sequence encoding a hetero logous heme protein, and a DNA sequence encoding a preregion permitting secretion of the expressed heme protein, and (b) culturing the transformed filamentous fungus in a suitable culture medium under conditions conducive to the production of the heme protein.

 

Furthermore, this technology can increase the total yield of such heme protein considerably. This is possible by adding hemin or another material containing heme groups to a fermentation medium for growing microorganisms which overproduce the apoprotein of a heme protein, the heme group is bound to the protein whereby the apoprotein is activated and acquires a conformation in which it is more stable against proteolytic degradation. In this way, endogenous heme synthesis in the host organism, which is often a bottle-neck in the expression of heme proteins, may be overcome.

 

Detailed Description:  In this context, the term heme protein is intended to include any member of a group of proteins containing heme (e.g. protoporphyrin IX) as a prosthetic group. The term apoprotein indicates a form of the heme protein lacking the prosthetic group. The term extracellular heme protein is understood to indicate that unlike the heme proteins provided in the prior art by production in bacteria or yeast, the apoprotein form of the heme protein is secreted from the host cell into the culture medium where it recombines (to the holoprotein) with the prosthetic heme group provided by addition of heme or heme-containing material to the medium.

 

The cloning and expression of varius heme proteins in bacteria has previously been described. The enzyme is expressed intracellularly as an insoluble aggregate so that it has to be purified from lysed cells. Furthermore, the enzyme is not expressed in active form and must be folded separately in the presence of heme and Ca2+ to become functional.  Expression of human hemoglobins in yeast has also been described. In yeast, hemoglobin is expressed as a fully assembled, heme-containing tetramer. However, the protein is not secreted from the yeast cells, but remains in the cytoplasmic space and must be purified therefrom.

 

However, the technology presented here, and covered by the patents below, provides a method whereby it is possible not only to produce heme proteins but also of exporting them through the cell membrane in active form, thereby simplifying purification procedures. Further, these basic method allows for the production of heme proteins in filamentous fungi in yields which far exceed those obtainable for the same protein in yeast.

 

A specific process represented by one  granted US patent (US5958724) consists of the following: 

 

 

The heme protein produced by the process of the present invention could e.g. be an enzyme, e.g. an oxidoreductase such as a peroxidase,  lignin peroxidase, Mn-peroxidase, or haloperoxidase.

 

Another important aspect of this technology is obtain significantly increased yields of pro tein by adding hemin or another material containing heme groups to a fermentation medium for growing microorganisms which overproduce the apoprotein of a heme protein. Hereby the heme group is bound to the protein whereby the apoprotein is activated and acquires a conformation in which it is more stable against proteolytic degradation. The total yield of heme protein is significantly increased. In this way, endogenous heme synthesis in the host organism, which is often a bottle-neck in the expression of heme proteins, may be overcome. Thus method comprises culturing a heme apoprotein producing microorganism in a fermentation medium containing heme or a heme-containing material under conditions permitting the production of active, recombined heme protein, and recovering the resulting heme protein from the medium. The medium used to culture the transformed host cells may be any conventional medium suitable for growing the host organism in question. The heme or heme-containing material added to the medium to obtain recombination of the secreted apoprotein with the heme group may suitably be supplied by the addition of hemin or, preferably, hemoglobin or red blood cells as the heme group remains functional on heating, permitting autoclaving of media containing one of these substances.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 Patent References
Patent Number:  
AT505311, BE505311, CH505311, DE505311,

DK505311, ES505311, FR505311, GB505311, GR505311, IT505311, NL505311, SE505311, US5744323, US5958724  
AT180837,DE69325169.7DK631631ES631631FR631631

GB631631, IT631631, NL631631, US5681725  

 

Abstract: This invention is well adapted to use for reducing microbial contamination of water systems, especially recirculating water systems, such as cooling water or recycled water in the paper and pulp industry (e.g. "white water" or "back water").

Detailed Description:  The present invention relates to an enzyme useful as an algalcide and slime inhibitor and more particularly to a novel alginate lyase which can be used to degrade algae cells and hold down the growth of slimes.

 

It is well known that uncontrolled growth of microorganisms in a cooling water system (that recirculates the water) can lead to deposit formation which contribute to fouling, corrosion and scale. Slimes can clog piping, hinder heat transfer or otherwise interfere with the proper functioning of a cooling water system. Presence of algae, Chroococcus, Osci llatoria and Chlorococcus in cooling water systems have been identified as causing fouling. In addition, algal slimes seem to become habitat for corrosive bacteria, and perhaps pathogenic bacteria.

 

Alginic acid (alginate) which is a polysaccharide constitutes the main element of algal cell walls. In some species of algae such as Fucus distichus, alginate makes up to 60% of the total cell wall. In addition to algae, some bacteria common in cooling waters, e.g. Pseudomonas spp. produce an extracellular polysaccharide polymer (slime) which results in fouling, formation of gases and protection of corrosive bacteria in cooling water systems. The extracellular polysaccharide polymer (slime) produced by some Pseudomonas spp. has been identified as alginate (L.R. Evans et al., J. Bacteriol. 1973, 116:915-924).

 

Alginate is a copolymer of three main structural blocks, poly-©¬-D-mannuronic acid (poly-M), poly-¥á-L-guluronic acid (poly-G), and blocks in which both uronic acids occur in what is believed to be an alternating sequence (poly-MG) (A. Haug et al., Acta Chem. Scand. 1967, 21:691-704).

 

Thus, the action of enzymes such as alginate lyases capable of depolymerizing alginate in the algal cell wall and slimes from Pseudomonas spp. can cause lysis of these organisms and/or increase the susceptibility of these organisms to the chemical biocides which customarily are in cooling water systems. Either result renders these troublesome micro-organisms unviable, which consequence is most desirable for best operation of cooling water systems.

 

As has already been indicated the alginate lyase of this invention is well adapted to use for reducing microbial contamination of water systems, especially recirculating water systems, such as cooling water or recycled w ater in the paper and pulp industry (e.g. "white water" or "back water"). The enzyme can be used at temperatures from ambient to 70°C, especially 40-60°C, and at pH 4-9, especially 5-8." A solid or liquid (concentrate) form of the alginate lyase is added to the recirculating water in effective amounts.

Patent References
Patent Number: 

EPO 434752, US 5139945, WO 09002794