Evaluation of the effectiveness of killer toxins produced by some strains of yeasts against other strains killer.

To make the wine, you do not need killer strains used for the purpose of dominance. It is only necessary that the yeasts are neutral. The aim of this study was to evaluate the effectiveness of killer toxins produced by some strains to produce a lethal effect on other strains killer. The experiments were conducted using the medium must Lorena M80: 20 with methylene blue. The killer test strains used were: 7M, 12M, 24M, 25M and 30M isolated from grape berries derived from the cultivar Merlot municipality of Pinto Bandeira (RS, Brazil). These strains were tested against other strains isolated killer Pinto Bandeira, they being the 3CF lineage derived from the cultivar Cabernet Franc, and the 24A strain isolated from cultivar Ancelota,; and also against strains isolated from the city of Colombo (PR, Brazil), called 4C, 6C, 7C, 10C, 11C, 12C, 13C, 14C, 15C, 17C, 19C, 20C, 22C and 24C. Were also used in the reference 1B, 91B and K1 strains. The inoculated plates were placed in an oven at 18 ° C 48 to 72 hours. The results revealed that none of the isolates showed sensitivity of these regions with the killer of five strains isolated killer test Merlot. However, the pattern and 91B K1 strains are sensitive to the killer factor produced by strains 30M and 12M. The 7M line introduced himself as killer only with respect to strain 91B. The taxonomic identification was first performed by amplifying the ITS region. Thus, three of the five strains analyzed, 7M, 24M and 25M, showed an amplicon at 610 base pairs.Resumo expandido

Monitoring of biogas production from tannery solid wastes at-line in a laboratory-scale anaerobic digester

Content: The understanding of how chemical, physical and environmental parameters work during anaerobic digestion production and waste treatment is an important step in improving the efficiency and process stability. This study provides the evolution of the biogas production and the efficiency of the treatment of the anaerobic digestion of solid wastes of tanneries at-line monitored in batch laboratory-scale bioreactors. Leather shavings and sludge from wastewater treatment plants substrates were considered in the study. The findings suggest that AD of the tannery solid waste can be separated into three phases: a long lag phase, a log phase with a low metabolic rate and the final phase where all the shavings were metabolized. Take-Away: The AD of the tannery solid waste can be separated into three phases: a long lag phase, a log phase with a low metabolic rate and the final phase where all the shavings were metabolize

Caracterização das leveduras isoladas de uvas das cultivares Malvasia Bianca e Moscato Alexandria da região de Farroupilha-RS.

O objetivo deste trabalho foi avaliar a capacidade fermentativa, a produção de sulfeto de hidrogênio, a formação da proteína killer e a sensibilidade ao fator killer de 100 linhagens de leveduras coletadas das bagas de uvas das cultivares Malvasia Bianca e Moscato de Alexandria da região de Farroupilha- RS

Identificação taxonômica de leveduras ambientais por espectrometria de massa MALDI-TOF.

O objetivo deste trabalho foi identificar, por MALDI-TOF MS, 99 leveduras isoladas de uvas cultivadas no Vale do São Francisco/PE para inseri-las na Coleção de Leveduras do Centro Nacional de Pesquisa de Uva e Vinho (WDCM 1056)

Microencapsulation of clove essential oil with gelatin and alginate

Content: Essential oils are of commercial interest primarily because of their potential antimicrobial, antifungal and antioxidant properties and for being of natural origin, which generally represents lower risk to the environment and human health. Clove essential oil not only contains many kinds of biological active compositions but also has highly effective and comprehensive antibacterial functions. Remarkably, clove has strong antimicrobial activities against a wide range of pathogenic microorganisms. To prevent chemical changes the oil is microencapsulated. The aim of this study is to develop essential oil microcapsules with gelatin and alginate. Various solutions were prepared for the capsule wall material at different concentrations. The encapsulation efficiency (%) was accessed and the microcapsules were characterized by oil content (%), oil charge (%), morphology, functional groups present, thermogravimetric analysis and by Fourier transform - infrared spectral analysis. FT-IR spectra of the clove oil shows some special peaks at 1148,01 and 1033,33 cm-1. The spectra of the capsule showed peaks 1148.34 and 1033.29 cm -1, the same peaks present in clove oil, showing that the encapsulation did not alter the structure of the oil's main assets. In case of the gelatin and alginate microcapsules containing clove oil, most of the characteristic peaks of clove oil remained unchanged, indicating the successful incorporation of clove oil into the microcapsules and the chemical stability of the clove oil after encapsulation. In otherwords, there was no significant chemical interaction between the oil and the wall of the microcapsule. Take-Away: The clove oil was microencapsulated according the FTIR spectra

Autochthonous yeast populations from different brazilian geographic indications.

Yeasts are versatile microorganisms which show heterogeneity in their abilities of aromatic molecules formation. The metabolic conversions may improve the production of a particular compound already formed by the microorganism or promote the production of a completely new biochemicals. These conversions depend on the environment. The microbiome of terroir is unique. If the term terroir is a set of physical properties of a vineyard that contribute to the specific characteristics of its wine, the microorganisms will undoubtedly form an integral part of this concept. There are yeasts, filamentous fungi and bacteria that can affect the quality of the wine. The aim of the present study was to identify the autochthonous yeast populations of grape berries collected from regions with Geographic Indications or under construction. The identification was carried out by an approach, combining Maldi-Tof-MS, PCR-RFLP of the internal transcribed spacer with 5.8S ribosomal DNA (rDNA) (ITS1-5.8S-ITS2) and sequences of the D1/D2 domain of the 26S rRNA gene. Some species are common to different GIs and in some of them other species are completely absent, besides some places are contiguous areas. In some areas, Hanseniaspora opuntiae, Saccharomyces cerevisiae, Pichia myanmarensis and Hanseniaspora uvarum were the predominant species.Também publicado em: CONGRESSO MUNDIAL DA VINHA E DO VINHO, 39., 2016, Bento Gonçalves. Programa...Bento Gonçalves, RS: International Organisation of Vine and Wine (OIV): Ministério da Agricultura, Pecuária e Abastecimento, de 19 a 21 outubro, 2016. Artigo nº 7, 02030. 2016

Potencial de Controle de Penicillium crustosum por leveduras.

Fungos filamentosos são exímios contaminantes de alimentos e, de forma geral, são formadores de micotoxinas. Penicillium crustosum, em especial, é capaz de formar a roquefortina C e uma forte neurotoxina denominada penitrem A

Impact of fungicide residues on polymerase chain reaction and on yeast metabolism.

The indiscriminate use of pesticides on grape crops is harmful for consumers´ healthin “in natura” consumption and in the ingestion of wine and grape juice. During winemaking, a rapid and efficient fermentation stage is critical to avoid proliferation of contaminating microorganisms and to guarantee the product´s quality. Polymerase chain reaction (PCR) has the advantage of detecting these contaminants in the early stages of fermentation. However,this enzymatic reaction may also be susceptible to specific problems, reducing its efficiency. Agricultural practices, such as fungicide treatments, may be a source of PCR inhibiting factors and may also interfere in the normal course of fermentation.The action of the pesticides captan and folpet on PCR and on yeast metabolism was evaluated, once these phthalimide compounds are widely employed in Brazilian vineyards. DNA amplification was only observed at 75 and 37.5 µg/mL of captan concentrations, whereas with folpet, amplification was observed only in the two lowest concentrations tested (42.2 and 21.1µg/mL).Besides the strong inhibition on Taq polymerase activity, phthalimides also inhibited yeast metabolism at all concentrations analyzed.Grape must containing captan and folpet residues could not be transformed into wine due to stuck fermentation caused by the inhibition of yeast metabolism. Noncompliance with the waiting period for phthalimide fungicides may result in financial liabilities to the viticulture sector.The use of yeasts with high fungicide sensitivity should be selected for must fermentation as a strategy for sustainable wine production and to assure that products comply with health and food safety standards. Key words: fungicide;PCR inhibitors; stuck fermentation;Taq polymerase inhibitors; yeast growt