Synergistic hypolipidemic and hypoglycemic effects of mixtures of Lactobacillus nagelii/betanin in a mouse model

Purpose: To determine the nutraceutical effect of mixtures containing Lactobacillus nagelii/betanin on the carbohydrate and lipid metabolism of mice.Methods: Lactobacillus nagelii and betanin were isolated from the raw materials. These components were subsequently assessed for their anti-hyperglycemic and hypolipidemic activities, and administered individually or combined in normoglycemic and diabetic mice. These animals were subjected to a standard OGTT and given an atherogenic diet.Results: The combination of L. nagelii (2.0 × 109 CFU/mL) and betanin (30 mg/kg body weight) exerted a significant (p < 0.01) and prolonged reduction of postprandial blood glucose (30 - 120 min). Interestingly, a mixture of L. nagelii (1 ×107 CFU/mouse/day) with betanin (10 mg/kg body weight) administered for 30 days, produced favourable effects (p < 0.01) in the lipid profile of mice previously treated with an atherogenic diet. These mixtures significantly ameliorated (p < 0.01) hypoinsulinemia, hyperleptinemia and increased the levels of adiponectin.Conclusion: The simultaneous administration of L. nagelii and betanin in mice produced a beneficial change in blood glucose and lipids in mice, indicating a synergistic nutraceutical effect. However, there is a need to develop this therapy further for potential application in humans Keywords: Lactobacillus nagelii, Betanin, Anti-hyperglycemic, Hypolipidemi

Chía, una semilla con potencial

Opinión sobre el potencial nutrimental de la Chía y sus usos para tratamiento de algunas enfermedades

Caracterización de bacterias Gram positivas utilizables como cultivos iniciadores para productos cárnicos

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Química-Física Aplicada. Fecha de lectura: 28-09-201

Screening of biogenic amine production by coagulase-negative staphylococci isolated during industrial Spanish dry-cured ham proceses

The potential to produce biogenic amines was investigated for 56 coagulase-negative staphylococci isolated during industrial Spanish dry-cured ham processes. The presence of biogenic amines from bacterial cultures was determined by thin-layer chromatography. The percentage of strains that decarboxylated amino acids was very low (3.6%). The only staphylococci with aminogenic capacity were an histamine-producing Staphylococcus capitis strain, and a Staphylococcus lugdunensis strain that simultaneously produced putrescine and cadaverine. In both strains, PCR was used to confirm the presence of the genes encoding the amino acid decarboxylases responsible for the synthesis of these amines. This study reveals that production of biogenic amines is not a widely distributed property among the staphylococci isolated from Spanish dry-cured hamsThis work was supported by Grants AGL2005-00470 (CICYT), RM03-002 (INIA), and ALIBIRD-CAM S-0505/AGR/000153 (CAM). The technical assistance of M.V. Santamaría is greatly appreciated. G. Landeta is a recipient of a predoctoral fellowship from CONACyT.S0505/AGR-000153/ALIBIRDPeer reviewe

Use of recA gene sequence analysis for the identification of Staphylococcus equorum strains predominant on dry-cured hams

Spanish dry-cured ham is an uncooked meat product highly appreciated due to its characteristics flavour. In this study, we examined the accuracy of biochemical tests and 16S rDNA sequencing in the identification of 56 staphylococcal strains isolated during industrial Spanish dry-cured ham processes. Important differences were observed comparing genotypic and phenotypic data. Staphylococcus xylosus was the prevalent species identified by biochemical methods (87.5%), however, sequencing of the 16S rDNA resulted in an unambiguous identification of Staphylococcus equorum (73.2%) and Staphylococcus vitulinus (8.9%) strains. Reliable identification of meat staphylococci, mainly among S. xylosus and S. equorum strains could be also achieved by means of recA gene sequence comparison. Two degenerate primers previously described for lactic acid bacteria were used to amplify an internal fragment of the recA gene. This fragment was amplified from twelve staphylococcal type strains representing frequent meat species. The results indicated that recA sequencing is an adequate method to discriminate among meat staphylococci. In addition, S. xylosus and S. equorum strains could be more accurately discriminated by recA sequencing than 16S rDNA or sodA sequencing. The S. equorum sequence diversity showed at the intra-species level by recA gene sequencing confirmed the high heterogeneity described among S. equorum strains. © 2011 Elsevier Ltd.This work was supported by grants RM2008-00002(Instituto Nacional de Investigación Agraria y Alimentaría), AGL2008-01052, Consolider INGENIO 2010 CSD2007-00063 FUN-C-FOOD(Comisión Interministerial de Ciencia y Tecnología), and S-0505/AGR/000153 and S2009/AGR-1469 (ALIBIRD)(Comunidad de Madrid). We are grateful to M. V. Santamaría and J. M. Barcenilla. G. Landeta is a recipient of a predoctoral fellowship from the CONACyT.Peer Reviewe

Technological and safety properties of lactic acid bacteria isolated from Spanish dry-cured sausages

Technological and safety-related properties were analyzed in lactic acid bacteria isolated from Spanish dry-cured sausages in order to select them as starter cultures. In relation to technological properties, all the strains showed significative nitrate reductase activity; Lactobacillus plantarum, Lactobacillus paracasei and 52% of the Enterococcus faecium strains showed lipolytic activity and only Lactobacillus sakei strains (43%) were able to form biofilms. Related to safety aspects, E. faecium strains were the most resistant to antibiotics, whereas, L. sakei strains were the most sensitive. In relation to virulence factors, in the E. faecium strains analyzed, only the presence of efaA gene was detected. The analysis of biogenic amine production showed that most E. faecium strains and L. sakei Al-142 produced tyramine. In conclusion, L. paracasei Al-128 and L. sakei Al-143 strains possess the best properties to be selected as adequate and safe meat starter cultures. © 2013.This work was supported by grants RM2008-00002 and RM2012-00004 (Instituto Nacional de Investigación Agraria y Alimentaria), AGL2008-01052, AGL2011-22745, Consolider INGENIO 2010 CSD2007-00063 FUN-C-FOOD (Comisión Interministerial de Ciencia y Tecnología), and S2009/AGR-1469(ALIBIRD) (Comunidad de Madrid).Peer Reviewe

Characterization of coagulase-negative staphylococci isolated from Spanish dry cured meat products

Technological and safety-related properties were analyzed in a coagulase-negative staphylococci (CNS) collection isolated from Spanish dry-cured meat products in order to use them as starter cultures. The highest nitrate reductase and proteolytic activity was showed by Staphylococcus carnosus and Staphylococcus equorum. Only a few strains were able to form biofilms and the presence of the ica gene was analyzed on them. In relation to antibiotic resistance, all S. carnosus and most of the S. equorum strains were sensitive to the antibiotics tested and the presence of the blaZ gene in the β-lactamic resistant strains was studied. Biogenic amines were produced by 25% of the strains analyzed being all the S. carnosus strains tyramine producers. Taking into account the studied properties, two S. equorum strains could be selected as adequate and safe potential starter cultures for the elaboration of meat products. © 2012 Elsevier Ltd.This work was supported by grants RM2008-00002 (Instituto Nacional de Investigación Agraria y Alimentaria), AGL2008-01052, AGL2011-22745, Consolider INGENIO 2010 CSD2007-00063 FUN-C-FOOD (Comisión Interministerial de Ciencia y Tecnología), and S2009/AGR-1469 (ALIBIRD) (Comunidad de Madrid). We are grateful to M. V. Santamaría and J. M. Barcenilla. J. A. Curiel and G, Landeta are recipients of predoctoral fellowship from the FPI-MEC, and CONACyT, respectively.Peer Reviewe

Biogenic amine production by bacteria isolated from ice-preserved sardine and mackerel

The occurrence of in vitro production of biogenic amines in bacteria isolated from ice-preserved sardine and mackerel was studied. Biogenic amine production was investigated by means of amino acid decarboxylation by growth on decarboxylase differential medium, biogenic amine detection by thinlayer chromatography (TLC) and decarboxylase gene detection by PCR. Decarboxylase medium overestimate the number of biogenic amine-producer strains, as the production of amine was confirmed by TLC in only five out the 17 presumptive strains. On the producer strains, PCR was used to confirm the presence of the genes encoding the amino acid decarboxylase responsible for the synthesis of these amines. Moreover, biogenic amine-producer bacteria were molecularly identified by sequencing their 16S rRNA. Form sardine, enterobacteria producing simultaneously several biogenic amines were isolated. A Kluyvera intermedia strain producing histamine, putrescine and cadaverine, and an Enterobacter asburiae strain producing only the diamines cadaverine and putrescine were identified. From mackerel, lactic acid bacteria from the Enterococcus durans species producing tyramine were isolated. This study constitutes the first description of the presence on these putatively harmful species on ice-preserved sardine and mackerel.This work was supported by grants RM2008-00002 (Instituto Nacional de Investigación Agraria y Alimentaria), AGL2008-01052, Consolider INGENIO 2010 CSD2007-00063 FUN-C-FOOD (Comisión Interministerial de Ciencia y Tecnología), S2009/AGR-1469 (ALIBIRD) (Comunidad de Madrid), Tunisian Ministry of High Education and Scientific Research and Programa de Cooperación Interuniversitaria e Investigación Científica (AECI), Ministerio de Asuntos Exteriores y Cooperación, Spain (B/019335/08). We are grateful to M. V. Santamaría and J. M. Barcenilla. J. A. Curiel and G. Landeta are recipients of predoctoral fellowships from the I3P-CSIC and CONACyT, respectively.Peer Reviewe