Project description:Background: Salmonella Typhimurium is a gram-negative enteropathogen that infects millions worldwide; the rapid emergence of antibiotic resistant strains has heightened the urgency of developing effective treatment for this pathogen. Previous studies have demonstrated that the aqueous extract of yerba mate (Ilex paraguariensis) provides effective therapy, in vitro, for the drug-resistant S. Typhimurium DT104. Unfortunately, while some of the chemical constituents that contribute to the extract’s antibacterial activity have been identified, the mechanism of action of the extract is still unknown and of crucial importance to its future potential in combating antibiotic resistant bacteria.</br> Results: Yerba mate extract altered central carbon metabolism in S. Typhimurium, reduced catalase activity by means other than direct inhibition, and did not change membrane integrity (except at the initial 0 time point, where differences were not resolved) despite a significant increase in the production of a cell wall precursor. Additional significant differences were observed in the global metabolic regulators alpha-ketoglutarate and acetylphosphate, the energy-related molecule NAD+, and in an unexpected match to the antibacterial compound yohimbine.</br> Conclusions: This work provides the first insight into the mechanism of action of yerba mate extract on S. Typhimurium by revealing a major impact on central carbon metabolism, catalase activity, and possible metabolic links to interference in energy production and membrane integrity. The putative identification of the antibacterial compound yohimbine and the many unidentified compounds provides additional avenues for future investigations of novel yerba mate compounds capable of traversing or binding to S. Typhimurium’s membrane.
Project description:The aqueous extract of yerba mate, a South American tea beverage made from Ilex paraguariensis leaves, has demonstrated bactericidal and inhibitory activity against bacterial pathogens, including methicillin-resistant Staphylococcus aureus (MRSA). The gas chromatography-mass spectrometry (GC-MS) analysis of two unique fractions of yerba mate aqueous extract revealed 8 identifiable small molecules in those fractions with antimicrobial activity. For a more comprehensive analysis, a data analysis pipeline was assembled to prioritize compounds for antimicrobial testing against both MRSA and methicillin-sensitive S. aureus using forty-two unique fractions of the tea extract that were generated in duplicate, assayed for activity, and analyzed with GC-MS. As validation of our automated analysis, we checked our predicted active compounds for activity in literature references and with used authentic standards to test for antimicrobial activity. 3,4-dihydroxybenzaldehyde showed the most antibacterial activity against MRSA at low concentrations in our bioassays. In addition, quinic acid and quercetin were identified using random forests analysis and 5-hydroxy pipecolic acid was identified using linear discriminant analysis. We additionally also generated a ranked list of unidentified compounds that may contribute to the antimicrobial activity of yerba mate against MRSA. Here we utilized GC-MS data to implement an automated analysis that resulted in a ranked list of compounds that likely contribute to the antimicrobial activity of aqueous yerba mate extract against MRSA.
2015-03-19 | MTBLS170 | MetaboLights
Project description:Community structure and diversity of the root associated microbiome of Ilex paraguariensis St. Hil (Yerba Mate)
| PRJNA310211 | ENA
Project description:Community structure and diversity of the root-associated microbiome of Ilex paraguariensis St. Hil (Yerba Mate)
| PRJNA310202 | ENA
Project description:Acidogenic Fermentation of Cheese Whey
Project description:Yerba mate (YM) has been shown to have anti-inflammatory properties in several studies. However, this effect has been found mainly in obesity-related in inflammation. The aim of this work was to study the effect of YM in cultured peripheral blood mononuclear cells to see whether it has anti-inflammatory properties. We stimulated peripheral blood mononuclear cells in vitro with phitohemaglutinin in the presence of yerba mate and determined their activation measuring the the expression of CD25 by flow cytometry. We observed that YM treatment produced a dose-dependent reduction in PBMC activation (CD25 positive cells) when they were stimulated with PHA. This effect was also observed in T cells (CD3 positive) subpopulation. Microarray analysis revealed the differential expression of 128 genes in YM-treated cells. According to a protein-protein interaction database, these genes were highly connected and they are involved in inflammatory response. In summary, it was demonstrated that YM produces a reduction in the amount of activated cells under the stimulation of PHA. Therefore, it might be used in diseases with an inflammatory component. PBMC samples from a healthy individual were cultured and stimulated with phytohemagglutinin. Gene expression of yerba mate treated and non-treated cells was analyzed in duplicates, having in total four microarrays.
Project description:Community structure and diversity of the root-associated microbiome of Ilex paraguariensis St. Hil (Yerba Mate) after bio-inoculation with Kosakonia radicincitans YD4
Project description:The engineering of Saccharomyces cerevisiae strains for lactose utilization has been attempted with the intent of developing high productivity processes for alcoholic fermentation of cheese whey. A recombinant S. cerevisiae flocculent strain that efficiently ferments lactose to ethanol was previously obtained by evolutionary engineering of an original recombinant that displayed poor lactose fermentation performance. In this study, we compared the transcriptomes of the original and the evolved recombinant strains (T1 and T1-E, respectively) growing in lactose, using cDNA microarrays. Microarray data revealed 173 genes whose expression levels differed more than 1.5-fold. About half of these genes were related to RNA mediated transposition. We also found genes involved in DNA repair and recombination mechanisms, response to stress, chromatin remodelling, cell cycle control, mitosis regulation, glycolysis and alcoholic fermentation. These transcriptomic data are in agreement with some of the previously identified physiological and molecular differences between the recombinants, and point to further hypotheses to explain those differences.
Project description:Yerba mate (YM) has been shown to have anti-inflammatory properties in several studies. However, this effect has been found mainly in obesity-related in inflammation. The aim of this work was to study the effect of YM in cultured peripheral blood mononuclear cells to see whether it has anti-inflammatory properties. We stimulated peripheral blood mononuclear cells in vitro with phitohemaglutinin in the presence of yerba mate and determined their activation measuring the the expression of CD25 by flow cytometry. We observed that YM treatment produced a dose-dependent reduction in PBMC activation (CD25 positive cells) when they were stimulated with PHA. This effect was also observed in T cells (CD3 positive) subpopulation. Microarray analysis revealed the differential expression of 128 genes in YM-treated cells. According to a protein-protein interaction database, these genes were highly connected and they are involved in inflammatory response. In summary, it was demonstrated that YM produces a reduction in the amount of activated cells under the stimulation of PHA. Therefore, it might be used in diseases with an inflammatory component.