Isolation and taxonomic study of a new canthaxanthin-containing bacterium, Gordonia jacobaea MV-1 sp. nov

This article describes the isolation and taxonomic study of a coryneform isolate of a new Gordonia species (G. jacobaea), strain MV-1, which accumulates several carotenoids, including the ketocarotenoid trans-canthaxanthin. Identification of this new isolate by morphobiochemical methods did not allow unambiguous taxon assignment, but sequencing of the 16S rRNA gene clearly pointed to the genus Gordonia, Gordonia sputi being the closest fit. Differences in certain transversions/ transitions in otherwise very well-conserved sequences of the described Gordonia species supported the proposal of this new taxon. The fact that both the best growth and best pigmentation were obtained with glucose, an inexpensive carbon source and at an industrially suitable temperature, suggests that this new bacterial strain may have good potential for the industrial production of canthaxanthin

Potential probiotic and functional properties of Brettanomyces strains isolated from kombucha tea

Kombucha, a beverage traditionally obtained through the fermentation of tea, is believed to have beneficial health properties. Therefore, characterizing the microorganisms responsible for this fermentation is essential to demonstrate its potential health benefits and to identify candidates for new probiotics. In this study, four probiotic yeast strains isolated from kombucha tea were identified, by the PCR-RFLP analysis of the ribosomal ITS region and the sequence of the D1/D2 domain of the 26S rDNA, as Brettanomyces bruxellensis (UVI55 and UVI56) and B. anomalus (UVI57 and UVI58). Properties relevant to probiotics were also studied in these strains. All of them showed excellent survival in simulated gastric (99%–100%) and duodenal (95%–100%) juices. The ability to self-aggregate (38%–100%), adhesion to xylene (15%–50%) and, above all, adhesion to Caco-2 cells (4%–21%), revealed its potential capacity to adhere to the intestinal epithelium. In addition, the tested strains showed excellent antioxidant capacity (82%–94%), antimicrobial activity against different pathogens (Escherichia coli, Staphylococcus aureus, Salmonella enterica, Listeria monocytogenes, and Bacillus cereus), as well as remarkable cytotoxic activity against colon, melanoma and ovarian tumor cell lines. Finally, using Caenorhabditis elegans as a model, strain UVI56 exhibited ability to both extend the lifespan of the nematode and protect it against infection by S. enterica. These results support the probiotic and functional properties of the analyzed strains. In conclusion, the study revealed that kombucha tea could be a source of potential probiotics that contribute to its health-promoting properties and that the characterized Brettanomyces strains could be exploited directly as probiotics or for the development of new functional foods.info:eu-repo/semantics/publishedVersio

Potential probiotic and functional properties of Brettanomyces strains isolated from kombucha tea

Kombucha, a beverage traditionally obtained through the fermentation of tea, is believed to have beneficial health properties. Therefore, characterizing the microorganisms responsible for this fermentation is essential to demonstrate its potential health benefits and to identify candidates for new probiotics. In this study, four probiotic yeast strains isolated from kombucha tea were identified, by the PCR-RFLP analysis of the ribosomal ITS region and the sequence of the D1/D2 domain of the 26S rDNA, as Brettanomyces bruxellensis (UVI55 and UVI56) and B. anomalus (UVI57 and UVI58). Properties relevant to probiotics were also studied in these strains. All of them showed excellent survival in simulated gastric (99%–100%) and duodenal (95%–100%) juices. The ability to self-aggregate (38%–100%), adhesion to xylene (15%–50%) and, above all, adhesion to Caco-2 cells (4%–21%), revealed its potential capacity to adhere to the intestinal epithelium. In addition, the tested strains showed excellent antioxidant capacity (82%–94%), antimicrobial activity against different pathogens (Escherichia coli, Staphylococcus aureus, Salmonella enterica, Listeria monocytogenes, and Bacillus cereus), as well as remarkable cytotoxic activity against colon, melanoma and ovarian tumor cell lines. Finally, using Caenorhabditis elegans as a model, strain UVI56 exhibited ability to both extend the lifespan of the nematode and protect it against infection by S. enterica. These results support the probiotic and functional properties of the analyzed strains. In conclusion, the study revealed that kombucha tea could be a source of potential probiotics that contribute to its health-promoting properties and that the characterized Brettanomyces strains could be exploited directly as probiotics or for the development of new functional foods.Agencia Estatal de Investigación | Ref. PID2022-138330OB-100Xunta de Galicia | Ref. GPC-ED431B 2023/35Xunta de Galicia | Ref. ED481A-2020/19

Contribution of critical doses of iprovalicarb, mepanipyrim and tetraconazole to the generation of volatile compounds from Monastrell-based wines

Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGThe individual effects of iprovalicarb, mepanipyrim, and tetraconazole on the volatile composition and aromatic profile of Monastrell-based wines were evaluated. To date, no studies about the effect of these fungicides on Monastrell-based wines are available, and the effect on other grape varieties is also unknown. Fungicides were added separately in the cellar to the grape must at two concentration levels (4 and 10 mg/kg for iprovalicarb and mepanipyrim and 1 and 2.5 mg/kg for tetraconazole). The aromatic composition of the final wines was analysed by gas chromatography using flame ionisation and ion trap mass selective detectors. In the presence of fungicides, the most significant variations were observed for isoamyl acetate and 2-phenylethyl acetate (increasing between 20 and 43% compared with the control wine) and ethyl caprate and caprylate (increasing between 12 and 68%). Consequently, treated wines showed a higher global odourant intensity, with increased fresh fruit notes.Ministerio de Economía y Competitividad | Ref. AGL2015-66491-C2-1-RAgencia Estatal de Investigación | Ref. PID2019-105061RB-C2

Mepanipyrim residues on pasteurized red must influence the volatile derived compounds from Saccharomyces cerevisiae metabolism

The impact of mepanipyrim (Mep) and its corresponding commercial formulation (Mep Form) on Saccharomyces cerevisiae metabolites was assessed, separately, by using laboratory-scale wine fermentation assays on pasteurized red must. The presence of Mep did not alter the fermentation course. With regard to volatiles formed at the intracellular level by fermenting yeast cells, Mep residues affected mainly the acetate and ethyl ester biochemical pathways. In particular, the target acetates showed a notorious increment, >90%, in presence of commercial Mep Form at the higher dose assayed. The addition of Mep and Mep Form, at both tested levels, highly increased ethyl caprylate (between 42 and 63%) and ethyl caprate (between 36 and 60%) contents as the same as their respective fatty acid precursors. No important effects were observed on colour and non-volatile pyranoanthocyanins, probably due to the low anthocyanin content characteristic of pasteurized musts.Xunta de Galicia | Ref. EM2013/004POCTEP | Ref. 0377_IBERPHENOL_6_EMinisterio de Economía y Competitividad | Ref. AGL2015-66491-C2-1-

Generating new fanca-deficient hnscc cell lines by genomic editing recapitulates the cellular phenotypes of fanconi anemia

Fanconi anemia (FA) patients have an exacerbated risk of head and neck squamous cell carcinoma (HNSCC). Treatment is challenging as FA patients display enhanced toxicity to standard treatments, including radio/chemotherapy. Therefore, better therapies as well as new disease models are urgently needed. We have used CRISPR/Cas9 editing tools in order to interrupt the human FANCA gene by the generation of insertions/deletions (indels) in exon 4 in two cancer cell lines from sporadic HNSCC having no mutation in FA-genes: CAL27 and CAL33 cells. Our approach allowed efficient editing, subsequent purification of single-cell clones, and Sanger sequencing validation at the edited locus. Clones having frameshift indels in homozygosis did not express FANCA protein and were selected for further analysis. When compared with parental CAL27 and CAL33, FANCA-mutant cell clones displayed a FA-phenotype as they (i) are highly sensitive to DNA interstrand crosslink (ICL) agents such as mitomycin C (MMC) or cisplatin(ii) do not monoubiquitinate FANCD2 upon MMC treatment and therefore (iii) do not form FANCD2 nuclear foci, and (iv) they display increased chromosome fragility and G2 arrest after diepoxybutane (DEB) treatment. These FANCA-mutant clones display similar growth rates as their parental cells. Interestingly, mutant cells acquire phenotypes associated with more aggressive disease, such as increased migration in wound healing assays. Therefore, CAL27 and CAL33 cells with FANCA mutations are phenocopies of FA-HNSCC cells

Evaluation of PFGE and mtDNA restriction analysis methods to detect genetic diversity of saccharomyces cerevisiae strains associated to <em>Vitis vinifera</em>

Aims: The aim of this work was realize a comparative study of two different methods of Saccharomycec cerevisiae yeast strain characterization. Methods and results: Pulsed-field gel electrophoresis analysis (PFGE) and mitochondrial DNA (mtDNA) restriction analysis have been carried out to differentiate strains of Saccharomyces cerevisiae associated to Vitis vinifera musts from different Galicia wineyard (NW Spain). Seventeen strains isolated from wineries from Galicia were used in this study. Conclusion: The results have showed that although PFGE analysis technique has greater discriminatory power than mtDNA restriction analysis to detect genetic diversity in Saccharomyces cerevisiae, some clones with the same PFGE profile can only be differentiated by mtDNA restriction analysis. Significance and impact of study: Pulsed-field gel electrophoresis analysis of chromosome (PFGE), by its discriminating power, constitute an ideal technique for the differentiation of Saccharomyces cerevisiae strains in biotechnological industries, however, mitochondrial DNA (mtDNA) restriction analysis is a rapid, simple and less expensive and time-consuming method. The results obtained demonstrate the value of using molecular genetic methods in taxonomic and ecological surveys

Wine lactic acid bacteria with antimicrobial activity as potential biocontrol agents against fusarium oxysporum f. sp. lycopersici

Lactic acid bacteria isolated from wine fermentations, particularly from the malolactic fermentation, and belonging to Lactobacillus plantarum, Lactobacillus hilgardii, Lactobacillus paracasei and Lactococcus lactis species were tested for their effectiveness in inhibiting the development of different microorganisms. The different strains showed, to varying degrees, an antagonistic effect against bacteria of the genera Bacillus and Staphylococcus. The specificity of the species L. hilgardii that inhibits only strains of the genus Bacillus is remarkable, on the other hand, L. plantarum was more effective against the strains of the genus Staphylococcus. The greatest effectiveness, considering both the degree of inhibition and the number of inhibited species, was presented by strains of L. lactis and L. paracasei. Seven strains belonging to the species that showed a more broad-spectrum activity, L. paracasei and L. plantarum, were also tested for their ability to inhibit the growth of fungi. All of them showed, in different degree (55–76%), activity against Fusarium oxysporum. Finally, the ability of the L. paracasei LPAUV12 and L. plantarum LPLUV10 strains was evaluated to protect Lycopersicon esculentum plants against the fungus F. oxysporum and promote its growth. Strain LPLUV10, showed capacity to significantly inhibit the harmful effect of F. oxysporum in tomato plants as well as to significantly stimulate their growth.Universidade de Vigo | Ref. CN2012/108The Sustainable Use Network of Environmental and Agrifood Resource-REDUSO | Ref. CN2012/10