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Grape juice is a major source of potential health-promoting bioactive polyphenols, especially for children and those who do not consume wine. Since the subtropical climate may negatively affect the concentrations of grape polyphenols, especially anthocyanins, elicitors such as methyl jasmonate (MeJa) could be used to promote polyphenol biosynthesis. This work aimed at investigating the impact of MeJa treatment on grape juice produced via a traditional low-cost process from two Vitis labrusca cultivars and in two Brazilian regions. The untargeted LC-MS analytical protocol demonstrated that Isabel Precoce juices strongly benefited from MeJa treatment, especially regarding their anthocyanic profile, regardless of the cultivation region. Known MeJa markers in wine and V. vinifera grapes (flavanols, flavonols and stilbenes) in this experiment had mixed behaviours depending on the region/variety/cultivation. Moreover, it was found that all the detected hydroxycinnamates were influenced by the treatment, especially the concentration of their glucosides, which was increased. Glutathione, 2-S-glutathionyl caftaric acid and indole lactic acid glucoside were identified for the first time as MeJa treatment biomarkers in grape products, indicating a possible positive effect on juice antioxidant properties.

Miliin, a new thiol-dependent serine protease purified from the latex of Euphorbia milii possesses a molecular weight of 79 kDa, an isoelectric point of 4.3 and is optimally active at 60 degrees C in the pH range of and 7.5-11.0. Activity tests indicate that milliin is a thiol-dependent serine protease.

Resumo -O objetivo deste trabalho foi avaliar o efeito de tratamentos pré-colheita sobre a ocorrência de podridões pós-colheita e sobre os atributos de qualidade de framboesas (Rubus idaeus L.) 'Heritage'. As frutas foram pulverizadas com um dos seguintes tratamentos: água destilada (controle), 6 g L -1 de quitosana, 100 mg L -1de dióxido de cloro, Bacillus amyloliquefaciens, Curtobacterium pusillum ou Saccharomyces cerevisiae. Foram realizadas colheitas aos 3, 7 e 14 dias após a aplicação dos tratamentos. Após cada uma das colheitas, realizadas no estádio de maturação comercial (coloração rosa), as frutas foram inoculadas individualmente com suspensão de conídios (2x10 5 conídios mL -1 ) de Botrytis cinerea ou Rhizopus stolonifer. As frutas foram mantidas a 12±0,5ºC por sete dias e avaliadas quanto à incidência de podridões e quanto aos principais atributos de qualidade. Bacillus amyloliquefaciens, C. pusillum e S. cerevisiae proporcionaram menor área abaixo da curva de progresso da incidência das podridões por Botrytis e Rhizopus. Os agentes de controle biológico avaliados não interferem negativamente sobre os atributos de qualidade das frutas, e, portanto, são alternativas potenciais no controle de podridões pós-colheita de framboesas.Termos para indexação: Bacillus amyloliquefaciens, Curtobacterium pusillum, Rubus idaeus L., Saccharomyces cerevisiae, controle biológico, pequenas frutas, quitosana. Alternative control of raspberry postharvest decayAbstract -The objective of this work was to evaluate the effect of pre-harvest treatments on post-harvest decay and on quality of 'Heritage' raspberries (Rubus idaeus L.). Fruit were sprayed with one of the following treatments: distilled water (control), 6 g L -1 of chitosan, 100 mg L -1 of chlorine dioxide solution, Bacillus amyloliquefaciens, Curtobacterium pusillum or Saccharomyces cerevisiae suspensions. Harvest was done at 3, 7, and 14 days after spray treatment. After each harvest, at commercial maturity (when fruit were pink), fruit were individually inoculated with conidial suspension (2x10 5 conidia mL -1 ) of Botrytis cinerea or Rhizopus stolonifer. Fruit were kept at 12±0.5ºC for seven days and were evaluated for decay and main quality attributes. Bacillus amyloliquefaciens, C. pusillum, and S. cerevisiae provided smaller area under disease progress curve of decays caused by Botrytis and Rhizopus. The biological control agents evaluated do not adversely affect fruit quality attributes, and, therefore, are potential alternatives to control post-harvest decay of raspberries.Index terms: Bacillus amyloliquefaciens, Curtobacterium pusillum, Rubus idaeus L., Saccharomyces cerevisiae, biological control, berries, chitosan. IntroduçãoAs pequenas frutas são muito apreciadas por sua coloração, sabor, aroma e textura, e, mais recentemente, têm sido valorizadas pelos benefícios proporcionados à saúde, decorrentes dos elevados teores de antioxidantes, vitaminas, minerais, fibras, ácido fólico, entre outros (Zhao, 2007). As framboesas (Rubus idaeus L.) destacam-se po...