Alejandra Londero

Learn More
Kefir-a traditional beverage whose consumption has been associated with health benefits-is a logical natural product to investigate for new probiotic strains. The aim of the present work was to isolate and identify kefir yeasts and select those with acid and bile tolerance to study their adhesion to epithelial cells and their transit through mouse gut. From(More)
The biological and technological characteristics of kefiran as well as its importance in grain integrity led us to analyze the microbial kefir grain consortium with focus on Lactobacillus kefiranofaciens. The presence of L. kefiranofaciens in the nine kefir grains studied was demonstrated by denaturing gradient gel electrophoresis. By culture dependent(More)
In this work, a method based on Raman spectroscopy in combination with Principal Component Analysis (PCA) and Partial Least Square-Discriminant Analysis (PLS-DA) has been developed for the rapid differentiation of heterofermentative related lactobacilli. In a first approach, Lactobacillus kefir strains were discriminated from other species of(More)
We investigated the chemical and microbiological compositions of three types of whey to be used for kefir fermentation as well as the inhibitory capacity of their subsequent fermentation products against 100 Salmonella sp. and 100 Escherichia coli pathogenic isolates. All the wheys after fermentation with 10% (wt/vol) kefir grains showed inhibition against(More)
We report here a comparative analysis of the growth, acidification capacity, and chemical and microbiologic composition between kefir grains after 20 subcultures in whey at 20, 30, and 37°C and the original kefir grains coming from milk along with a determination of the microbiological composition of the fermented whey as compared with that of traditional(More)
BACKGROUND Fungal contamination of poultry feed causes economic losses to industry and represents a potential risk to animal health. The aim of the present study was to analyze the effectiveness of whey fermented with kefir grains as additive to reduce fungal incidence, thus improving feed safety. RESULTS Whey fermented for 24 h at 20 °C with kefir grains(More)
Several foods contaminated with Shiga toxin-producing Escherichia coli (STEC) are associated with human diseases. Some countries have established microbiological criteria for non-O157 STEC, thus, the absence of serogroups O26, O45, O103, O104, O111, O121, and O145 in sprouts from the European Union or ground beef and beef trimmings from the United States is(More)
Shiga toxin-producing Escherichia coli (STEC) are important emerging foodborne human pathogens. Ruminants are the main animal reservoir of STEC currently known, and meat can become contaminated at different stages of the production chain. The aim of this work was to subtype and establish the epidemiological relatedness of non-O157 STEC strains isolated from(More)
Listeriosis is a foodborne disease caused by Listeria monocytogenes. The aims of this work were to develop and validate an in-house real-time polymerase chain reaction (RT-PCR) for the detection of L. monocytogenes, and to determine its prevalence in raw ground beef samples from 53 butcheries that also sell ready-to-eat foods. One set of primers and one(More)
  • 1