ABSTRACT
Different oak species or origins have been studied to find an alternative to traditional ones and Quercus humboldtii from Colombia is a candidate. Some studies analyse the composition of this oak, but no work has been found to study its use for wine treatment. The aim was to evaluate volatile composition of toasted Q. humboldtii oak chips and the wines treated with these chips. To evaluate its oenological potential Q. alba and Q. petraea have been included in this trial. The wines were subjected to a sensory analysis. Results indicated that oak chips and wines macerated for 90â¯days with toasted Colombian chips exhibited higher 5-methylfurfural, guaiacol, trans-isoeugenol and syringol concentrations than others, while the furfural and cis-ß-methyl-γ-octalactone content was lower. Sensory analysis showed that the wines treated with Colombian oak presented more notes of smoked and less of coconut. Therefore, this oak could probably be considered suitable for ageing.
Subject(s)
Quercus/chemistry , Volatile Organic Compounds/chemistry , Wine/analysis , Colombia , Europe , Furaldehyde/analogs & derivatives , Furaldehyde/analysis , Gas Chromatography-Mass Spectrometry , Guaiacol/analysis , North America , Principal Component Analysis , Quercus/metabolism , Volatile Organic Compounds/analysis , Wood/chemistryABSTRACT
A alveolite seca (AS) é uma das complicações pós-operatórias mais comuns e sintomáticas na odontologia, porém, até o momento não há um protocolo de tratamento definido. O composto fenólico guaiacol (Gu) é um dos materiais utilizados para revestimento intra-alveolar devido às suas propriedades analgésicas, antioxidantes e antimicrobianas. Contudo, sua desvantagem é a dificuldade de manipulação decorrente da sua baixa estabilidade, alta volatilidade e sensibilidade à oxidação. Para melhorar suas propriedades e aumentar sua aplicabilidade clínica, um complexo de inclusão de Gu com ß-ciclodextrina (ßcd) foi desenvolvido. A formação do complexo supramolecular de Gu:ßcd foi caracterizada mediante a ressonância magnética nuclear (RMN), nos experimentos de 1H e 2D ROESY. A atividade antibacteriana do Gu e Gu:ßcd frente a Escherichia coli, Staphylococcus aureus, Streptococcus mitis, Streptococcus mutans, Streptococcus sanguis e Aggregatibacter actinomycetemcomitans foi analisada pelo método da microdiluição e sua citotoxicidade em osteoblastos de calvária de rato, foi estudado com o ensaio do MTT. O processo de reparo alveolar induzido pelo Gu:ßcd foi avaliado histologicamente após tratamento de alveolite seca em molares inferiores de ratos. A RMN mostrou correlações espaciais entre os hidrogênios internos (H3 e H5) da ßcd e os hidrogênios aromáticos, H(a) e H(b) do Gu, confirmando a formação do complexo. A complexação do Gu na ßcd potencializou seu efeito antibacteriano e reduziu sua citotoxicidade em osteoblastos. O estudo in vivo evidenciou a ocorrência de ossificação no ápice alveolar dos ratos tratados com Gu:ßcd, no 7o dia. No 14o dia, as trabéculas ósseas ocuparam também o terço médio do alvéolo e no 21o dia, todo o alvéolo se encontrava preenchido por osso neoformado. Estes resultados foram similares ao controle negativo e superiores ao controle positivo (Alvogyl®). Os benefícios obtidos pela inclusão do Gu na ßcd foram demonstrados pela melhora das...
Dry socket is one of the most common and symptomatic complications in dentistry, however, there is still not a settled treatment for this condition. The phenolic compound guaiacol (Gu) is one of several alveolar dressings used in dry socket because it has analgesic, antioxidant and antimicrobial properties. Nevertheless, its disadvantage is the difficulty of manipulation due to its low stability, high volatility and sensitivity to oxidation. To improve its properties and increase its clinical applicability, an inclusion complex of Gu with ß-cyclodextrin (ßcd) was developed. The Gu:ßcd supramolecular complex was characterized by Nuclear Magnetic Ressonance (NMR), in the 1H and 2D ROESY experiments. The antibacterial activity of Gu and Gu:ßcd over Escherichia coli, Staphylococcus aureus, Streptococcus mitis, Streptococcus mutans, Streptococcus sanguis and Aggregatibacter actinomycetemcomitans was analyzed using the microdilution method and its cytotoxicity in rat calvaria-derived osteoblast was evaluated with the MTT assay. The alveolus repair process induced by Gu:ßcd was histologically studied after the treatment of dry socket in rat mandibular molars. The NMR showed spatial correlations between internal hydrogens (H3 and H5) of ßcd and aromatic hydrogens, H(a) and H(b), of Gu confirming the inclusion complex formation. Gu:ßcd complex potentiated Gu antibacterial effect and reduced its cytotoxicity in osteoblasts. The in vivo study revealed that ossification occurred in the alveolar apex of rats treated with Gu:ßcd, by day 7. In the 14th day, the trabecular bone occupied the apical and middle thirds of the socket and on the 21st day, the entire alveolus was filled by newly formed bone. These results were similar to the negative control and superior to the positive control (AlvogylTM). Benefits gained from inclusion of Gu in cyclodextrin have been particularly demonstrated by the improvement in Gu biological properties in vitro and the appropriate alveolus...
Subject(s)
Humans , Male , Female , Dry Socket/complications , Dry Socket/diagnosis , Dry Socket/metabolism , Cyclodextrins/analysis , Cyclodextrins/adverse effects , Cyclodextrins/standards , Guaiacol/analysis , Guaiacol/adverse effectsABSTRACT
Yeasts belonging to the genus Dekkera/Brettanomyces, especially the species Dekkera bruxellensis, have long been associated with the production of volatile phenols responsible for off-flavour in wines. According to recent reports, the species Pichia guilliermondii could also produce these compounds at the initial stages of fermentation. Based on the abundance of P. guilliermondii in Patagonian winemaking, we decided to study the relevance of indigenous isolates belonging to this species as wine spoilage yeast. Twenty-three indigenous isolates obtained from grape surfaces and red wine musts were analyzed in their capacity to produce volatile phenols on grape must. The relationship between molecular Random Amplified Polymorphic DNA (RAPD) and physiological (killer biotype) patterns detected in indigenous populations of P. guilliermondii and volatile phenol production was also evaluated. Different production levels of 4-ethylphenol, 4-vinylguaiacol and 4-ethylguaiacol were detected among the isolates; however, the values were always lower than those produced by the D. bruxellensis reference strain in the same conditions. High levels of 4-vinylphenol were detected among P. guilliermondii indigenous isolates. The combined use of RAPD and killer biotype allowed us to identify the isolates producing the highest volatile phenol levels.
Subject(s)
Phenols/analysis , Pichia/isolation & purification , Volatile Organic Compounds/analysis , Wine/microbiology , Argentina , Dekkera/metabolism , Fermentation , Guaiacol/analogs & derivatives , Guaiacol/analysis , Killer Factors, Yeast/pharmacology , Mycological Typing Techniques , Pichia/drug effects , Pichia/genetics , Pichia/metabolism , Polymerase Chain Reaction , Random Amplified Polymorphic DNA Technique , Vitis/microbiology , Wine/analysisABSTRACT
Yeasts belonging to the genus Dekkera/Brettanomyces, especially the species Dekkera bruxellensis, have long been associated with the production of volatile phenols responsible for off-flavour in wines. According to recent reports, the species Pichia guilliermondii could also produce these compounds at the initial stages of fermentation. Based on the abundance of P. guilliermondii in Patagonian winemaking, we decided to study the relevance of indigenous isolates belonging to this species as wine spoilage yeast. Twenty-three indigenous isolates obtained from grape surfaces and red wine musts were analyzed in their capacity to produce volatile phenols on grape must. The relationship between molecular Random Amplified Polymorphic DNA (RAPD) and physiological (killer biotype) patterns detected in indigenous populations of P. guilliermondii and volatile phenol production was also evaluated. Different production levels of 4-ethylphenol, 4-vinylguaiacol and 4-ethylguaiacol were detected among the isolates; however, the values were always lower than those produced by the D. bruxellensis reference strain in the same conditions. High levels of 4-vinylphenol were detected among P. guilliermondii indigenous isolates. The combined use of RAPD and killer biotype allowed us to identify the isolates producing the highest volatile phenol levels.
Las levaduras del género Dekkera/Brettanomyces, sobre todo la especie Dekkera bruxellensis, siempre han sido asociadas con la producción de fenoles volátiles responsables de aromas desagradables en los vinos. Recientemente, se ha demostrado que la especie Pichia guilliermondii también es capaz de producir estos compuestos, particularmente durante las etapas iniciales de la fermentación. Dada la abundancia de P. guilliermondii en las bodegas de la Patagonia, se decidió evaluar la importancia de algunos aislamientos indígenas de esta especie como levaduras alterantes de vinos regionales. Se evaluó la capacidad de producir fenoles volátiles en ensayos sobre mosto de 23 aislamientos de P. guilliermondii provenientes de superficie de uvas y de mostos de fermentación de vinos tintos. Asimismo, se analizó la relación entre los patrones moleculares (RAPD) y fisiológicos (biotipo killer) de estos aislamientos y la producción de fenoles volátiles. Se detectaron diferentes niveles de producción de 4-etilfenol, 4-vinilguayacol y 4-etilguayacol entre los aislamientos de P. guilliermondii analizados; sin embargo, los valores obtenidos fueron en todos los casos inferiores a los producidos por D. bruxellensis cepa de referencia en las mismas condiciones. En general, se detectaron altos niveles de 4-vinilfenol en los mostos fermentados con los aislamientos indígenas de P. guilliermondii. El uso combinado de RAPD-PCR y el biotipo killer permitió identificar los aislamientos que producen los niveles más altos de fenoles volátiles.
Subject(s)
Phenols/analysis , Pichia/isolation & purification , Volatile Organic Compounds/analysis , Wine/microbiology , Argentina , Dekkera/metabolism , Fermentation , Guaiacol/analysis , Guaiacol/analogs & derivatives , Killer Factors, Yeast/pharmacology , Mycological Typing Techniques , Polymerase Chain Reaction , Pichia/drug effects , Pichia/genetics , Pichia/metabolism , Random Amplified Polymorphic DNA Technique , Vitis/microbiology , Wine/analysisABSTRACT
We report the evaluation of the floral origin of honey by analysis of its volatile organic compounds (VOCs) profile, joined with the use of combined pattern recognition techniques. Honey samples, from five floral origins, were analyzed by headspace solid-phase microextraction-gas chromatography-mass spectrometry, selecting 35 VOCs out of the entire profiles, which were analyzed by hierarchical cluster analysis (HCA), stepwise discriminant analysis (SDA), and K-nearest-neighbor (KNN). Both HCA and SDA were used as exploratory tools to select a group of VOCs representing similitude and differences among studied origins. Thus, six out of 35 VOCs were selected, verifying their discriminating power by KNN, which afforded 93% correct classification. Therefore, we drastically reduced the amount of compounds under consideration but kept a good differentiation between floral origins. Selected compounds were identified as octanal, benzeneacetaldehyde, 1-octanol, 2-methoxyphenol, nonanal, and 2-H-1-benzopyran-2-one. The analysis of VOC profiles, coupled to HCA, SDA, and KNN, provides a feasible alternative to evaluate the botanical source of honey.
Subject(s)
Flowers , Gas Chromatography-Mass Spectrometry/methods , Honey/analysis , Honey/classification , 1-Octanol/analysis , Aldehydes/analysis , Coumarins/analysis , Guaiacol/analysis , VolatilizationABSTRACT
O processo de reparo do alvéolo infectado de ratos (Rattus norvegicus, albinus, Wistar) foi avaliado após a limpeza cirúrgica e irrigaçäo com soro fisiológico seguida do preenchimento da loja com a pasta Sultan. Para tanto, todos os animais utilizados (8 ratos doadores e outros 60 animais experimentais) tiveram o incisivo central superior direito extraído e, alveolite provocada experimentalmente, nos animais doadores e naqueles dos Grupos I, II, III e IV. Os 60 ratos experimentais constituíram os seguintes Grupos: I. Alveolite sem tratamento; II. Limpeza cirúrgica e irrigaçäo; III. Pasta Sultan, apenas; IV. Limpeza cirúrgica e irrigaçäo mais pasta Sultan. Os animais, em número de cinco em cada grupo, foram sacrificados aos 6, 15 e 28 dias pós-operatórios e as peças obtidas incluídas em parafina, cortadas e coradas com hematoxilina e eosina para análise em microscopia óptica. Os resultados foram submetidos a análise qualitativa. Com base nos resultados foi possível concluir que: (1) O grupo da alveolite teve o reparo alveolar comprometido quanto a sua cronologia; (2) O grupo da limpeza cirúrgica seguida da irrigaçäo alveolar foi o que apresentou resultados superiores; (3) a pasta Sultan näo deve ser utilizada como curativo de preenchimento alveolar para o tratamento da alveolite