Int.J.Curr.Microbiol.App.Sci (2016) 5(8): 255-257

International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 5 Number 8 (2016) pp. 255-257 Journal homepage: http://www.ijcmas.com

Review Article http://dx.doi.org/10.20546/ijcmas.2016.508.026

Role of Lactic Acid Bacteria (LAB) in

J. Hitendra*, B. D. Narotham Prasad, H. Gurumurthy and V. C. Suvarna

Department of Agriculture Microbiology, UAS, GKVK, Bengaluru, *Corresponding author

ABSTRACT

K e yw or ds Lactic acid bacteria comprise an ecologically diverse group of microorganisms united by

formation of lactic acid as the primary metabolite of metabolism. Deserving an attention

Lactic Acid for its capabilities, this will discuss on the general description of lactic acid bacteria, genetics,

Bacteria (LAB), metabolism and its application to the industries. Bacterial antagonism has been recognized for Food over a century but in recent years this phenomenon has received more scientific attention, Preservation. particularly in the use of various strains of lactic acid bacteria One important attribute of many LAB is their ability to produce antimicrobial compounds called bacteriocins. In recent years Article Info interest in these compounds has grown substantially due to their potential usefulness as natural Accepted: substitute for chemical food preservatives in the production of foods with enhanced shelf life 12 July 2016 and / or safety. There is growing consumer awareness of the link between diet and health. Available Online: Recent scientific evidence supports the role of probiotic LAB in mediating many positive health 10 August 2016 effects. Traditional probiotic strains of lactic acid bacteria have a long history of safe use and most strains are considered commensal microorganisms with no pathogenic potential.

Introduction

Lactic acid bacteria (LAB) are variety of habitats, they are fastidious and microorganisms that have been used for amongst others nutrients they require centuries to prepare and improve storage of fermentable carbohydrates, amino acids, food and for ensiling of different crops for fatty acids, and vitamins for their animal feed. Lactic acid bacteria were first growth (Björkroth & Holzapfel, 2006). described as -souring organisms, due to Historically, the core group comprises the the sour milk that arose from their genera , Leuconostoc, production of lactic acid. They are a Pediococcus and Streptococcus, but the relatively diverse group of bacteria, but main LAB genera important in food- related by a number of typical metabolic and technology also include Aerococcus, physiological features. Generally the group Carnobacterium, Lactococcus, Oenococcus, consists of gram-positive bacteria, cocci or Tetragenococcus, Vagococcus and Weisella.

rods, that are non-sporulating, non-respiring Lactic acid bacteria are commonly found and produce lactic acid as the major end in foods, including fermented meat, product during fermentation of vegetables, fruits, beverages, dairy products, carbohydrates. in the respiratory, intestinal and genital

LAB are normally found in nutrient-rich tracts of humans and animals, in sewage, environments. Even if they grow in a and in plant materials (De Vuyst and Vandamme, 1994).

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Int.J.Curr.Microbiol.App.Sci (2016) 5(8): 255-257

Lactic acid bacteria are added to the food as The common lactic acid food fermentation cultures and are generally considered to be of India includes pickles, , , harmless or even have an advantage for Gunpanga, Dahi, Srikhanda, Bhallae, human heath in United States, they are Punjabi, woni, , Dhoka Sinks, recorded as GRAS (Generally Regarded As mesu, Gendruk, Jhord, soyrubadi, Soy- Safe). sauce, Ambai and Bona.

Lactic acid food fermentation are common LAB can be regarded as homo- or in tropical climates as a low cost method of heterofermentative, depending on how they enhancing food quality, safety and shelf life. ferment hexoses under non-limited growth Indians discovered this method of souring conditions. The homofermentative LAB use and leavening cereals, legumes batters. the glycolysis (Embden-Meyerhof-Parnas) Egyptians developed wheat leavened pathway, resulting in lactic acid as the main with yeast and Koreans and credited for the end product resulting in lactic acid, carbon production of acid fermented vegetable. dioxide and ethanol (or acetic acid) as the

Bio Preservation of foods using lactic acid major end products. However, homo- and bacteria also enhance the quality of food hetero fermentative LAB cannot be mainly due to the production of primary distinguished solely on their production of metabolite lactic acid, which results in certain fermentation Hetero fermentative decrease of pH. Many lactic acid bacteria LAB use the 6-phosphogluconate/ are capable of inhibiting the growth of wide phosphoketolase pathway (6-PG/PK) variety of food spoilage organisms. products. Mechanisms exploited in preservation is their potency to produce inhibiting agent. Lactic acid bacteria are known to compete The classic example of commercially with other microbes by modifying the successfully naturally produced Nisin. microenvironment by their metabolic end products. Besides lactic acid, bacteriocins Fermentation was among the first few and non-proteinaceous low molecular mass methods of food conversion. Fermentation compounds (LMMC) are produced by LAB was due to the activity of non- toxic in foods and contribute to the antimicrobial microorganisms. This might have developed effects of added LAB cultures. Benzoic acid, when mankind started collecting and storing methylhydantoin and mevalonic acid lactone food. Lactic acid bacteria involved in food contribute to the microbicidal action of conversion for example milk undergoes an Lactobacillus plantarum (Niku et al., 1999), acid fermentation naturally, readily and the and reuterin and pyroglutamic acid to those acid protects the milk from spoilage by of L. reuteri. These biologically active undesirable microorganisms in the substances differ from bacteriocins since environment. Fermentation helps in LMMCs display a wide spectrum of activity reducing toxins and antinational factor. against both Gram-positive and Gram- Fermentation enhances the nutrient negative bacteria and fungi. availability in the product, B-complex, protein efficiency ratio, Fe solubility, Vaughan et al., (1994) examined LAB enzymes, volume are increased. Many isolated from variety of foods and found that biochemical changes also take pace during presence of LAB in fruits and vegetables is fermentation, sugar and non protein nitrogen comparatively very low when compared are released. with , milk and meat. Isolated lactic

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Int.J.Curr.Microbiol.App.Sci (2016) 5(8): 255-257 acid bacteria have greater potential in Springer, New York, pp. 267-319. inhibiting the spoilage causing bacteria. De Vuyst, L., Vandamme, E.J. 1994. Nisin, Moreover, growing public awareness about lantibiotic produced by Lactococcus the use of pesticide, together with the lactis subsp. lactis: properties, development of resistant pathogens and biosynthesis, fermentation and possible toxicological risks has prompted applications. In: De Vuyst L., the search for alternative approach. As LAB Vandamme E.J. (eds), Bacteriocins of is plenty in plant and plant associated lactic acid bacteria. Blackie, London, products, and moreover these LAB have pp. 151-221. GRAS (Generally Regarded As Safe) status Niku-Paavola, M.L., Laitila, A., Matilla- by FAO, there is a scope for using LAB Sandholm, T. and Haikara, A. 1999. isolated from plant and plant associated New types of antimicrobial products as biocontrol agent against compounds produced by Lactobacillus phytopathogens. plantarum. J. Appl. Microbiol., 86: 29- 35. References Vaughan, E.E., Capiio, E., Roarke, N.O. and Fritzgerad, 1994, Isolation from Bjorkroth, J., Holzapfel, W.H. 2006. Genera food source of lactic acid bacteria that Leuconostoc, Oenococcus and produced antimicrobials. J. Appl. Weissella, In M. Dworkin, S. Falkow, Bacteriol., 76: 118-123. E. Rosenberg, K.-. Schleifer, E. Stackebrandt (Eds.), The Prokaryotes,

How to cite this article:

Hitendra, J., B.D. Narotham Prasad, Gurumurthy and Suvarna, H. 2016. Role of Lactic Acid Bacteria (LAB) in Food Preservation. Int.J.Curr.Microbiol.App.Sci. 5(8): 255-257. doi: http://dx.doi.org/10.20546/ijcmas.2016.508.026

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