Antimicrobial products: An important feature of lab and their applications

Abstract

Lactic acid bacteria (LAB) are known to be present in diverse origins which are rich in nutrients and energy sources, for instance, milk, meat, plants and gastrointestinal tract of humans and animals. LAB that have extensively been found to belong to the genera Lactobacillus (Lb), Streptococcus (Strep), Enterococcus (Ec), Pediococcus (Ped), Lactococcus (Lc), Leuconostoc (Leuc), Aerococcus (A), Oenococcus (O), Carnobacterium (Cb), Vagococcus (V), Tetragenococcus (T), Weissella (W) and Fructobacillus (F) (a genus of fructophilic lactic acid bacteria). They can produce lactic acid as the primary metabolic end product via carbohydrate metabolisms. Therefore, various fermented foods are developed by the action of these bacteria. Antimicrobial compounds secreted by LAB have long been recognized to prolong the shelf-life and improve the safety of foods. LAB produce a variety of compounds, including lactic acid, acetic acid, hydrogen peroxide (H2O2), ethanol, formic acid, fatty acids, diacetyl, acetaldehyde, acetoin, reuterin, reutericyclin, bacteriocins, bacteriocin-like compounds and other low molecular mass compounds which exhibit the antimicrobial activity against spoilage and pathogenic microorganisms and germination of spore as well. LAB cultures are marketed today as protective cultures against common food spoilage bacteria and pathogens. Consequently, the application of such cultures may lead to improvements in food quality and sensory attributes by controlling spoilage microbiota. The use of antimicrobials from LAB as food preservatives has become a popular practice. Moreover, the addition of LAB as probiotics into food and medical products has also been reported.