Article

Antibiotic resistance in lactic acid bacteria and Micrococcaceae/Staphylococcaceae isolates from artisanal raw milk cheeses, and potential implications on cheese making.

Dairy Science and Technology Laboratory, Agricultural Research Center of Mabegondo (CIAM), Xunta de Galicia, 15080 A Coruña, Spain.
Journal of Food Science (impact factor: 1.66). 09/2009; 74(6):M284-93. DOI:10.1111/j.1750-3841.2009.01217.x
Source: PubMed

ABSTRACT Antibiotic susceptibility against 19 antimicrobial agents was evaluated in isolates of the genera Lactococcus (46 isolates), Leuconostoc (22), Lactobacillus (19), Staphylococcus (8), Enterococcus (7), and Microccoccus/Kocuria (5) obtained from the predominant microflora of nonrecent and recent types of artisanal raw cow's milk cheeses. Beta-lactams showed broad activity against all genera, although leuconostocs and lactobacilli were highly resistant to oxacillin (80% to 95.5%). Resistance to aminoglycosides was frequent for lactococci and enterococci (particularly for streptomycin), whereas lower rates of resistance were detected for lactobacilli and leuconostocs. Technologically interesting traits for the food industry were distributed among isolates that showed different degrees of resistance to common antibiotics. However, isolates showing resistance to less than 2 antibiotics were mainly those with properties of greatest technological interest (acidifying activity, proteolytic/lipolytic activities, or diacetyl production).

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Keywords

2 antibiotics
 
46 isolates
 
aminoglycosides
 
Antibiotic susceptibility
 
artisanal raw cow's milk cheeses
 
broad activity
 
common antibiotics
 
diacetyl production
 
enterococci
 
Enterococcus
 
genera
 
genera Lactococcus
 
greatest technological interest
 
Leuconostoc
 
leuconostocs
 
lower rates
 
nonrecent
 
showed different degrees
 
Technologically interesting traits
 

P Rodríguez-Alonso