Nisin applications

Potential therapeutic applications of host defense peptides also include the lantibiotic nisin. Indeed, nisin has had an impressive history as a food preservative with FDA approval in 1988 for use in pasteurized, processed cheese spreads. The attractiveness of nisin as a potential therapeutic is also enhanced due to its relative resistance to proteases and broad spectrum Gram-positive antimicrobial activity including multidrug-resistant strains. Biosynexus Inc. has licensed the use of nisin for human clinical applications and Immucell Corp. has licensed the use of Mast Out, an antimastitic nisin-containing product, to Pfizer Animal Health." Indeed, nisin formulations have been used as an active agent in the topical therapies Mast Out and Wipe-Out for bovine mastitis, an inflammatory disorder of the udder that is the most persistent disease in dairy cows." ... 

Research on antibiotics which do not produce multiple resistance is, of course, desirable. Nisin appears to present just such a situation although its applications are narrow. Some feed additives are capable of "curing multiple resistance in enterics (50). This area deserves more research and emphasis. 

With respect to synthetic methods, the most thoroughly investigated lanthionine from the group of alkylated lanthionines is threo-3-methyllanthionine (2), a lanthionine which is also found in a number of natural peptides such as nisin[12l and epidermin.14 In this section, some of the synthetic methods are compared and discussed with respect to their relative applicability and their possible extension to other alkylated lanthionines. 

From the data presented in Figure 3, it is likely that heat-stable LAB bacteriocins (other than nisin) may find suitable application as biologically-produced antimicrobials ("biopreservatives") in thermally-processed foods. Future studies directed towards the examination of a variety of novel bacteriocins in thermal processing applications may identify new LAB bacteriocin(s) which have comparable, or perhaps superior, properties as nisin. Further research is needed to determine the presence of bacteriocins in retail foods which may help to reduce the regulatory hesitancy towards their practical application as safe food ingredients. Data provided by research with the magainins and... 

Delves-Broughton J, Blackburn P, Evans RJ, Hugenholtz J. Applications of the bacteriocin, nisin. Antonie van Leeuwenhoek... 

Elevated temperature and citric acid have been found to increase the susceptibility to nisin, both in culture and in foods. Exposure to a temperature of 60°C for 10 min, followed by 24 h incubation by 30°C showed no survival of bacterial cells. However, at a temperature of 50°C some viable cells were found with the application of nisin, but survivor numbers were significantly reduced. Stationary phase cells are more resistant to both organic acids alone, as well as in combination with nisin, than log-phase cells. It is speculated that Gram-negative bacterial cells are protected from the effects of nisin by the composition of their outer layers. When these are weakened by elevated temperature, they become sensitive by similar mechanisms as Gram-positive bacteria (Phillips and Duggan, 2002). 

Yuste, J., Pla, R., Capellas, M., and Mor Mur, M. 2002. Application of high pressure processing and nisin to mechanically recovered poultry meat for microbial decontamination. Food Control 13 451 55. 

The antibiotic Nisin is inhibitory against several grampositive Streptococci, Lactobacilli, Clostridia, Staphylococci and Bacilli (61-62). Goel et al. (63) noted that the addition of Nisin increased the shelf life of low fat dairy spread (Table X). In 20 countries outside the United States, Nisin is permitted as a direct food additive (64), and one major application has been to prevent the growth and subsequent gas production by Clostridia in hard cheese and processed cheese products. In France, for example, Nisin-producing Streptococci have been employed in the manufacture of processed cheese. Nisin has also been studied as a possible alternative to nitrite in the preservation of meats (65). 

Gill, A. O. 2000. Application of lysozyme and nisin to control bacterial growth on cured meat products. MS thesis. The University of Manitoba, Winnipeg, Canada. 

Another important issue deals with antimicrobial food packaging, as detailed in Chapter 10. Antimicrobial packaging systems based on PLA would be superior to other antimicrobial materials due to its comparable cost, effective antimicrobial activity, few regulatory concerns and environmental friendliness. For example, the incorporation of bacteriocins into PLA matrices could provide a delivery system to improve their efficiency in food applications, e.g. PLA/nisin films show this behaviour and they have been proposed for commercial use. Actually, the PLA/nisin polymers can be used in bottle manufacturing or coated onto the bottle surface for use in liquid food packaging, as well as into films or coated on the surface of films for use in solid food packaging. 

Nisin is now approved for use as a food preservative in about 50 countries (10). The variety of the types of foods and beverages in which nisin has been successfully used continues to grow impressively. Most abundant are applications in dairy products (13,14), where nisin can inhibit the outgrowth of spores as well as being bacteriocidal agaiitst vegetative cells (15-17), increasing the shelflife of cheeses (18) and ice cream (19). 

Nisin HSTKDFNLDLVSVSKKDSGASPR Leader region) ITSISLCTPGCKTGALMGCNHKTATCHCSIHVSK (Niji-M Mature structure region) No No Not applicable 123,125... 

Medical applications of nisin, a food preservation additive... 

Applications. Nisin is permitted in some countries chiefly for the preservation of processed cheese and it is used in (fruit- and vegetable-) preserves as a sterilising auxiliary, but not in the United States or the EC. In the EC nisin can be applied in clotted cream, mascarpone, processed and ripened cheese in concentration around lOmg/kg. 

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