Search results for "lactobacillus"

THE GUT-BRAIN AXIS: EFFECTS OF THE PROBIOTIC LACTOBACILLUS FERMENTUM INTRODUCED IN THE DIET OF ETHANOL-FED MICE

2022

In situ riboflavin fortification of different kefir-like cereal-based beverages using selected Andean LAB strains.

2018

Cereal-based functional beverages represent social, economic, and environmental sustainable opportunities to cope with emerging trends in food consumption and global nutrition. Here we report, for the first time, the polyphasic characterization of three cereal-based kefir-like riboflavin-enriched beverages, obtained from oat, maize and barley flours, and their comparison with classical milk-based kefir. The four matrices were successfully fermented with commercial starters: i) milk-kefir and ii) water-kefir, proving the potential of cereal ingredients in the formulation of dairy-like fermented beverages with milk-kefir starter behavior better in these matrices. In the light of their potenti…

Genotypic characterization of lactic acid bacteria isolated from traditional Pecorino Siciliano cheese

2008

A total of 468 lactic acid bacteria (LAB) isolates from the interior of six traditional Pecorino Siciliano cheeses during ripening (1, 30 and 90 days) were characterized genotypically in order to assess the biodiversity within this wild microbial population. Two DNA-based technique, PCR and PFGE were used for genetic typing of isolates. Of the 468 isolates, species-specific PCR analysis showed that 79, 58, 2, 9 and 4 isolates reacted with primers for Lactobacillus paracasei, Lb. plantarum, Lb. pentosus, Lb. rhamnosus and Lb. curvatus, respectively and no isolates reacted with the Lb. casei primers. Genus-specific PCR analysis showed that 59 isolates reacted positively with the lactococcal p…

Identification des gènes impliqués lors de l'établissement de Lactobacillus casei dans l'intestin et caractérisation de l'opéron LSEI_0219-0221

2014

In bacteria which are in direct contact with their environment, genes transcription and proteins synthesis are efficiently regulated at each change of environmental parameters to allow cell survival. For intestinal commensal bacteria, these regulations must also allow symbiotic interactions and colonization whose molecular mechanisms, so far little known, are probably related, among others, to the bacteria surface (molecules exposed and secreted…). Lactobacillus casei, a commensal bacterium, has about 330 predicted genes involved in the composition and functionality of the cell surface. To have a global view of the whole genes involved in the establishment of L. casei in the gut, a reverse …

Animal rennets as sources of dairy lactic acid bacteria

2014

ABSTRACT The microbial composition of artisan and industrial animal rennet pastes was studied by using both culture-dependent and -independent approaches. Pyrosequencing targeting the 16S rRNA gene allowed to identify 361 operational taxonomic units (OTUs) to the genus/species level. Among lactic acid bacteria (LAB), Streptococcus thermophilus and some lactobacilli, mainly Lactobacillus crispatus and Lactobacillus reuteri , were the most abundant species, with differences among the samples. Twelve groups of microorganisms were targeted by viable plate counts revealing a dominance of mesophilic cocci. All rennets were able to acidify ultrahigh-temperature-processed (UHT) milk as shown by pH …

Use of gases to improve survival of Bifidobacterium bifidum by modifying redox potential in fermented milk

2011

The aim of this work was to study the effect of the oxidoreduction potential, modified using gas, on the growth and survival of a probiotic strain, Bifidobacterium bifidum, and 2 yogurt strains, Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus. Three fermented milks were manufactured with an initial oxidoreduction potential value adjusted to +440 mV (control milk), +350 mV (milk gassed with N(2)), and -300 mV [milk gassed with N(2) plus 4% (vol/vol) H(2) (N(2)-H(2))]. Acidification profiles, growth during milk fermentation and survival during storage at 4 °C for 28 d were determined. This study showed that fermented probiotic dairy products made from milk gassed with…

Transformation of raw ewes' milk applying “Grana” type pressed cheese technology: development of extra-hard “Gran Ovino” cheese

2019

Abstract This work was carried out to pursue a double objective: to improve the hygienic safety of cheeses produced from raw ewes' milk; and to produce a new typology of raw ewes' milk through the application of “Grana” technology for which the name “Gran Ovino” was chosen. With this in mind, raw milk from an individual farm was transformed under controlled conditions at a dairy pilot plant. The production technology included the partial skimming of the evening and morning milk mixture by cream surfacing and the addition of a natural whey starter cultures (NWSC) prepared with four selected Streptococcus thermophilus strains (PON6, PON244, PON261 e PON413). Ten microbial groups were investig…

In vivo application and dynamics of lactic acid bacteria for the four-season production of Vastedda-like cheese.

2014

article Twelve lactic acid bacteria (LAB), previously selected in vitro (Gaglio et al., 2014), were evaluated in situ for their potential to act as starter cultures for the continuous four-season production of Vastedda-like cheese, made with raw ewes' milk. The strains belonged to Lactobacillus delbrueckii, Lactococcus lactis subsp. cremoris, Leuconostoc mesenteroides subsp. mesenteroides and Streptococcus thermophilus .L AB werefirst inoculated in multiple-strain combinations on the basis of their optimal growth temperatures in three process conditions which differed for milk treatment and medium for strain development: process 1, growth of strains in the optimal synthetic media and pasteu…

Cell surface properties affect colonisation of raw milk by lactic acid bacteria at the microstructure level

2010

Cell localisation in the matrix microstructure of fermented food is important for microbial activity and ripening. To evaluate the importance of physicochemical factors in these phenomena, the physicochemical behaviour of four strains of lactic acid bacteria were investigated after inoculation of raw milk or milk fractions. To discriminate between physicochemical and metabolic properties, media were (i) rapidly acidified to avoid cell division or (ii) bacteria were allowed to ferment milk. To evaluate the impact of milk components, cells were dispersed in protein or fatty globule fractions. From two Lactococcus lactis subsp. lactis biovar. diacetylactis strains selected from their different…

Identification, typing, and investigation of the dairy characteristics of lactic acid bacteria isolated from 'Vastedda della valle del Belìce' cheese

2013

Traditional cheeses made without starter cultures can be characterised by the attribute of instability. The addition of autochthonous starter cultures can ensure stability without compromising the characteristics of the final product. This study aimed to characterise the autochthonous lactic acid bacteria (LAB) population in “Vastedda della valle del Belice” cheeses, which have a protected designation of origin (PDO) status, in order to develop an ad hoc starter culture to be used in its future production. Winter and spring productions were analysed to ensure isolation of specific LAB that had adapted to perform fermentation at low temperatures. Plate counts revealed total microbial numbers…