Evaluation of technologically important traits in lactic acid bacteria isolated from spontaneous fermentations

Abstract

A set of 120 isolates of Lactohadus (75), Lactococcus (25) and Leuconostoc (20), mainly isolated from natural starter-free fermentation processes, has been screened for some technologically important traits, including lactose hydrolysis, extracellular polysaccharide production, fermentation of carbohydrates, antimicrobial agent susceptibility and bacteriocin production. Some of the strains exhibited important features for particular fermentations. Furthermore, the sensitivity resistance phenotype to antimicrobials showed genusspecific patterns.

Antibiotic Resistance in Lactic Acid Bacteria and Micrococcaceae/Staphylococcaceae Isolates from Artisanal Raw Milk Cheeses, and Potential Implications on Cheese Making

“…faecalis isolates displayed resistance to up to 8 different antibiotics (oxacillin, spectinomycin, gentamicin, kanamycin, streptomycin, neomycin, clindamycin, and lincomycin) and variable resistance to furazolidone and tetracycline (data not shown). Similar results have also been observed in other studies with LAB (Herrero and others 1996; Danielsen and Wind 2003; Flórez and others 2005) and microstaphylococci (Gardini and others 2003; Perrin‐Guyomard and others 2005; Martín and others 2006) isolated from foods. This confirms that some bacterial resistance mechanisms are distributed among a wide variety of bacteria, whereas others appear to be more specific in certain species and genera of bacteria.…”

“…Lactobacilli and leuconostocs may have a natural resistance to aminoglycosides, but low rates of resistance were observed in the lactobacilli and leuconostocs in the present study, whereas more variable rates of resistance were found in lactococci and enterococci (Table 2). Similar results were obtained by Herrero and others (1996) for LAB isolated from different Spanish cheeses (La Serena, Gamonedo, Cabrales, Majorero) and wines (Utiel‐Requena, Montilla‐Moriles). These researchers also found that lactococci were the most resistant to aminoglycosides (especially gentamicin), whereas leuconostocs were very susceptible to these antibiotics.…”

“…Several studies have shown that LAB from foods appear to be quite sensitive to penicillins and cephalosporins (Herrero and others 1996; Charteris and others 1998; Danielsen and Wind 2003; Delgado and others 2005; Flórez and others 2005) and more resistant to oxacillin (Danielsen and Wind 2003). These observations were also confirmed in the present study as all of the LAB isolates from Galician raw milk cheeses were rather susceptible to β‐lactams (ampicillin, penicillin G, cephalothin), but a high resistance to oxacillin was observed in leuconostocs (21 out of 22; 95.5%), lactobacilli (16 out of 19; 84.2%), enterococci (5 out of 7; 71.4%), and lactococci (17 out of 46; 37.0%) (Table 2).…”

Isolation and Partial Characterization of Halotolerant Lactic Acid Bacteria from Two Mexican Cheeses

“…This low lypolitic activity of LAB may represent an important advantage when they are used as starter cultures, as only a slight breaking of the milk fat during maturation is enough to induce aroma production without giving a rancid flavor in cheese [70]. Results from this study allow us to conclude that HALAB isolates E. faecium, L. pentosus, L. plantarum, W. thailandensis, T. halophilus, and L. farciminis could be selected to be included as adjunct starter cultures, since they fulfilled the customary requirements for cheesemaking.…”

Selection of yoghurt starter culture from indigenous isolates ofStreptococcus thermophilus andLactobacillus delbrueckii subsp.bulgaricus on the basis of technological properties

“…bulgaricus (Masud et al, 1991). In modern production techniques, standardization, quality and safety of the product is considered to be of outstanding importance, therefore the mixtures of LAB strains are carefully selected to carry out the desirable fermentation processes (Herrero et al, 1996). The main technological properties of yoghurt bacteria during fermentation are acidification, texture enhancement and flavour production.…”