Protease detergent enzyme

For proteases (detergent enzymes) voluntary exposure limits of 0.4 (xg/ m have been set." By comparison, the limits on an 8-hour personal exposure to total inhalable dusts is 10 mg/m, i.e. 25 000 times higher than protease and 100 000 higher than the endotoxin concentration." ... 

Several new detergent enzymes have emerged on the market (Table 1). Truly alkaline proteases, introduced in 1974 and 1982, were fermented on strains of Bacillus lentus firmus. These enzymes have a pH optimum between 9 and 11, and have taken important market shares from Alcalase. 

In 1989, two enzymes based on genetic engineering techniques were introduced, ie, a cloned alkaline protease (IBIS) and a protein engineered Subtihsin Novo (Genencor, California). Lipase and ceUulase types of detergent enzymes have also begun to appear. 

The effectiveness of proteolytic, amylolytic, and lipolytic detergent enzymes is based on enzymatic hydrolysis of peptide, glucosidic, or ester linkages. The mainstay of the market has been the protease types. 

As mentioned in part 2.1.3 hydrolytic enzymes are the most frequently used enzymes in organic chemistry. There are several reasons for this. Firstly, they are easy to ttse because they do not need cofactors like the oxidoreductases. Secondly, there are a large amormt of hydrolytic enzymes available because of their industrial interest. For instance detergent enzymes comprise proteases, celltrlases, amylases and lipases. Even if hydrolytic enzymes catalyse a chemically simple reaction, many important featirres of catalysis are still contained such as chemo-, regio- and stereoselectivity and specificity. 

Since the mid-60s, the use of enzymes in detergents has been the largest of all enzyme applications. Over half of all detergents presently available contain enzymes, in particular proteases, amylases, lipases and ceUulases. Besides improved washing efficiency, the use of enzymes allows lower temperatures and shorter wash periods (of agitation) to be employed, often after a preliminary period of soaking. Further in this chapter (section 3.3) the detergent enzymes are worked out in more detail. 

Until the end of the sixties enzyme products such as the detergent proteases were just powder products. Today very few powdered-enzyme products remain. All detergent enzyme products from the larger enzyme suppliers arc either hquid formulations or granulated and further protected by coatings. Today formulation techniques really have become a science with MAC-values in production facilities of 10-100 nanogram/m air. It is further recommended that the use of such safe enzyme products shall be planned such that the liquid enzyme product is not spilled and allowed to diy and aerosol formation shall be prevented. With these simple rules in mind, industrial enzymes arc very safe. 

For nse in a detergent an enzyme mnst suffice the following criteria. In the first place it mnst have an adeqnate activity and stability at alkaline pH. It must also remain active and stable in a broad temperatme interval (e.g. 10-60°C). For domestic use the trend is to low temperatures (see 3.3.7 In-depth intermezzo). Additionally an enzyme should be resistant to hydrolysis and oxidation by other snbstances in the detergent, e.g. proteases. For enzymes with lanndry-softeiung properties two additional criteria apply, i.e. the enzyme must show a high fiber separation and at the same time not impair the fibers. Developments aim to further satisfy these criteria. 

In many applications several quite different technical criteria must be successfully fulfilled before the product will work , and even then cost and scale-up and commercial criteria must be met. A good example is detergent enzymes where scientists had to discover proteases that would be active and stable under conditions of high pH and temperature and in the presence of oxidising and surface active agents. The same criteria exists for lipases for use in detergents. However, suitable lipases proved rather more difficult to find than the B. subtilis proteases that are used... 

Extracellular proteases are of commercial value and find multiple applications in various industrial sectors. A good number of bacterial alkaline proteases are commercially available, such as Subtilisin Carlsberg, subtilisin BPN and Savinase, with their major application as detergent enzymes. 

Proteases are enzymes that catalytically degrade proteins, making them useful in the removal of all manner of proteinaceous and protein-containing stains such as blood, egg yolk, milk, grass, and collar soil. Because they perform well against such a wide variety of stains, proteases are the most commonly used type of detergent enzyme (see Table 1). 

World War II spurred much advancement in the production of penicillin, particularly the advent of submerged fermentation processes. This new technique was soon adapted to the large-scale production of bacterial proteases. The first modern detergent protease, isolated from Bacillus licheniformis, was introduced in 1962. This enzyme, a particular type of protease called a subtilase, was stable at higher temperatures, had broad substrate specificity and worked well in alkaline conditions. The appearance of this enzyme and others similar to it (i.e., subtilisins) opened up the detergent enzymes market, and by 1969, 50% of the laundry detergent products sold in the United States and Europe contained enzymes. ... 

Enzymes are an increasingly important component in detergent formulations, both in terms of effectiveness and as a means of product differentiation. The primary types of detergent enzymes are protease, amylase, lipase, and cellulase all are derived from bacterial and fungal sources. Enzyme activity is subject to various forms of chemical and physical degradation, problems that are particularly acute in liquid formulations, where the enzymes cannot be physically isolated from the harmful effects of surfactants and bleaches. 

Stoner, M.R. Dale, D.A. Gualfetti, P.J. Becker, T. Manning, M.C. Carpenter, J.F. Randolph, T.W. Protease autolysis in heavy-duty liquid detergent formulations Effects of thermodynamic stabilizers and protease inhibitors. Enzyme and Microbial Technology 2004, 34, 114—125. 

Protease is by far the most widely used of all detergent enzymes. Introduced in the 1960s, it has since become one of the more important components of detergent formulations [6]. Proteases aid in the removal of many soils commonly encountered by the consumer, such as food stains (cocoa, egg yolk, meat), blood, and grass. This enzyme hydrolyzes or breaks up the peptide bonds found in proteins resulting in the formation of smaller and more soluble polypeptides and amino acids. Since most enzymes have to function under high pH conditions, subtilisin, a bacterial alkaline protease, is commonly used in laundry detergents. This particular protease does not hydrolyze any specific peptide bond in proteinaceous stains but cleaves bonds in a somewhat random manner. 

Proteases are enzymes that break down protein molecules through peptide bond hydrolysis [1]. They are commercially employed in many industrial processes. In foods, proteases have two main applications in the processing of traditional food products and in the processing of new protein-based ingredients called functional foods [2]. Proteases are also used in other industrial segments such as leather industry, pharmaceutical, waste management, and the detergent industry. Currently, microbial proteases make up approximately 40% of total enzyme sales [3, 4]. 

Products containing up to four different enzymes—protease, amylase, lipase, and cellulase—are now on the market. The patent literature suggests that even more novel detergent enzymes are on the way. 

Synonyms Alcalase Bacillus subtilis Carlsberg Detergent enzyme Maxatase Protease, bacterial, alkaline... 

All of the preceding techniques are extensively used for the production of detergent enzymes such that today the vast majority of industrial enzymes are produced by recombinant techniques. This is done in a limited number of optimized, well-known production hosts. Some of the most frequently used host organisms are the Bacillus species—B. subtilis, B. licheniformis, and B. clausii, which are used for production of proteases and amylases. The lipases and cellulases of fungal origin are produced by cultivation of the filamentous fungi Aspergillus oryzae and Trichoderma reesei. 

Production of Proteases and Other Detergent Enzymes Antifoam agent... 

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