Draft Genome Sequence of the Feruloyl Esterase-Producing Strain Lactobacillus fermentum CRL1446, a Probiotic for Malnutrition.

We report here the draft genome sequence of Lactobacillus fermentum CRL1446 (2,148,781 bp, 51.4% G+C content). This strain exhibits feruloyl esterase activity and important technological and probiotic properties. Because of its proven beneficial effects in vivo, it represents an interesting candidate for the development of functional foods or pharmabiotics for malnutrition.

Lactobacillus fermentum CRL1446 Ameliorates Oxidative and Metabolic Parameters by Increasing Intestinal Feruloyl Esterase Activity and Modulating Microbiota in Caloric-Restricted Mice.

The purpose of this study was to determine whether the administration of the feruloyl esterase (FE)-producing strain Lactobacillus fermentum CRL1446 enhances metabolic and oxidative parameters in caloric-restricted (CR) mice. Balb/c male mice were divided into ad libitum fed Group (ALF Group), CR diet Group (CR Group) and CR diet plus L. fermentum Group (CR-Lf Group). CR diet was administered during 45 days and CRL1446 strain was given in the dose of 108 cells/mL/day/mouse. FE activity was determined in intestinal mucosa and content at Day 1, 20 and 45. Triglyceride, total cholesterol, glucose, thiobarbituric acid reactive substances (TBARS) levels and glutathione reductase activity were determined in plasma. Gut microbiota was evaluated by high-throughput sequencing of 16S rRNA gene amplicons. At Day 45, total intestinal FE activity in CR-Lf Group was higher (p = 0.020) than in CR and ALF groups and an improvement in both metabolic (reductions in triglyceride (p = 0.0025), total cholesterol (p = 0.005) and glucose (p < 0.0001) levels) and oxidative (decrease of TBARS levels and increase of plasmatic glutathione reductase activity (p = 0.006)) parameters was observed, compared to ALF Group. CR diet increased abundance of Bacteroidetes and CRL1446 administration increased abundance of Bifidobacterium and Lactobacillus genus. L. fermentun CRL1446 exerted a bifidogenic effect under CR conditions.

Contribution of lactic acid bacteria esterases to the release of fatty acids in miniature ewe's milk cheese models.

The present work evaluates the contribution of esterase activities of lactic acid bacteria isolated from ewe's dairy products to the release of free fatty acids (FFA) in ewe's milk cheese models. At 60 days of ripening, single-strain cheeses Ov 409 and Ov 421 showed high levels of total FFA (3075 and 2494.62 mg/kg, respectively). Cheeses Ov 227-Ov 409 and Ov 421-Ov 409 presented high percentages of short-chain fatty acids (SCFA). The highest levels of volatile free fatty acids (VFFA) were detected in cheeses Ov 409, Ov 421-Ov 409, and Ov 421-Ov 227. Studies on esterase activities showed that these strains hydrolyzed alpha-naphthyl derivatives of fatty acids from C2 to C6, mainly associated with the wall-membrane fraction. The results showed that the strains studied contributed to the release of FFA during ripening of ewe's milk cheese models. The increase of SCFA throughout ripening involves the action of esterases of starter strains.

Technological properties of Enterococcus faecium isolated from ewe's milk and cheese with importance for flavour development.

Eight Enterococcus faecium strains isolated from ewe milk and artisanal cheese from northwest Argentina were screened for biotechnological properties relevant to flavour development. The API ZYM test showed absence of proteases, presence of high amounts of peptidases, and high esterase-lipase activities. Low extracellular proteolytic activity was observed. Most strains produced diacetyl in milk, with E. faecium OvL 214 and OvL 254 being the best producers. Biomass and growth rate increased when citrate was added to the medium, suggesting that these strains could use citrate as a main energy source. After 24 h of incubation, citrate was completely consumed in complex medium supplemented with glucose and citrate. An average of 17% residual citrate was detected in complex media supplemented with citrate. For all strains, esterase activity was detected up to alpha-naphthyl-caproate. They hydrolyzed alpha-naphthyl derivatives of fatty acids in this order: C3 > C6 > C4 > C8 > C2. Post-electrophoretic detection of esterase activities revealed the presence of multiple esterases. Hydrolysis of tributyrin, tricaprylin, and milk fat was observed in cell-free extracts. Enterococcus faecium strains isolated from ewe milk and artisanal cheese from northwest Argentina present the metabolic potential to contribute to cheese flavour development.