Abstract This study evaluated relations among nutrients, bioactive compounds and antioxidant activity of commercial tomato varieties grown in field conditions in order to identify their biological potential by the Principal Component Analysis (PCA). Four commercial tomato varieties (Long Life, Italian, Khaki and Cherry), homogenized by their maturation stage (color, sugar/acidity ratio and pH) were evaluated regarding macro components (sugars, pectin and minerals) and functional ones (carotenoids, phenolic compounds and ascorbic acid). Cherry tomatoes stood out for their pectin and lycopene contents and their sugar/acidity ratio. Tomato samples were good sources of Cu and Ca. The PCA showed that the antioxidant potential of phenolic compounds was related to protocatecoic acid and quercetin concentrations. Italian and Cherry varieties stood out for their carotenoid contents. In field conditions, Cherry and Italian tomatoes were the best sources of functional compounds among the most common varieties found in the human diet.

Abstract This study evaluated the role of dry fruits as a source of fungal contaminants or functional compounds. Dry apple, apricot, candied fruits, prune, and white and black raisin were evaluated regarding patulin and ergosterol content, centesimal composition, pH, acidity, pectin, and phenolic profile. The ergosterol was detected in 38% of the samples and patulin (PAT) in 89%, the apricot samples stood out most by contaminant level. Apricot, candied fruit, and prunes presented moisture values beyond the other dry fruits. The pH ranged from 3.8 to 4.6; acidity from 0.1 to 1.0%; sugar content from 1.7 to 5.5%; and levels of soluble and insoluble pectin from 1.6 to 5.1% and 10.9% to 27.3%, respectively. The apples showed a higher content of free phenolic compounds (6.6 mg of gallic acid/g) with a predominance of gallic and protocatechuic acids. Pearson's correlation showed a significant positive correlation between patulin and ergosterol content (0.99) and soluble pectin (0.78); a significant negative relation between total sugars (-0.66) and free phenolic compounds (-0.63). Fungal contamination and the occurrence of PAT show that this mycotoxin is present and, therefore, the evaluation of fungal toxins in dry fruits is recommended before claiming them to be a source of functional compounds.

A aplicação de substâncias naturais com efeito antifúngico é motivada pela necessidade de alternativas aos métodos existentes que nem sempre são aplicáveis, eficientes ou sem risco de danos ao consumidor ou meio ambiente. Além disso, estudos para elucidar o comportamento de espécies toxigênicas mediante fungicidas naturais tornam-se necessárias, contribuindo dessa forma com a segurança alimentar. Neste trabalho, extrato fenólico de Spirulina foi utilizado para avaliar a atividade antifúngica sobre 12 cepas toxigênicas de Fusarium graminearum, isoladas de cevada e trigo. As rotas metabólicas que poderiam ser afetadas foram avaliadas através da determinação de compostos estruturais (glicosamina e ergosterol) e da atividade de enzimas do metabolismo primário dos micro-organismos. Os resultados indicaram que os extratos fenólicos reduziram a velocidade de crescimento das espécies toxigênicas estudadas. O IC50 foi obtido na concentração de 3% a 8% (p/p) de extrato fenólico. A utilização desse fungicida natural foi promissora para a inibição da multiplicação fúngica, em especial pela inativação dos sistemas enzimáticos (amilase e protease) de Fusarium graminearum.

The application of natural antifungal substances is motivated by the need for alternatives to existing methods that are not always applicable, efficient, or that do not pose risk to consumers or the environment. Furthermore, studies on the behaviour of toxigenic species in the presence of natural fungicides have enabled their safe application in the food chain In this study, Spirulina LEB-18 phenolic extract was assessed for its antifungal activity on 12 toxigenic strains of Fusarium graminearum isolated from barley and wheat. The susceptible metabolic pathways were assessed through the determination of structural compounds (glucosamine and ergosterol) and enzyme activity of the microorganisms' primary metabolism. The results indicate that phenolic extracts reduced the growth rate of the toxigenic species investigated. The IC50 was obtained by applying 3 to 8% (p/p) of phenolic compounds in relation to the culture medium. The use of this natural fungicide proved promising for the inhibition of fungal multiplication, especially in terms of the inactivation of enzymatic systems (amylase and protease) of Fusarium graminearum.

The objective of this work was to evaluate the solid-state fermentation with Rhizopus oryzae CCT 7560 of rice bran for the enrichment of proteins and the antioxidant compounds in the fermented biomass. Fermentation was performed in tray bioreactors at 30ºC for 120 h. Protein extraction was done at alkaline pH, followed by precipitation with acetone. Phenolic compounds were extracted with cold methanol. The maximum protein was recovered from after 120 h (26.6%). The content of total phenolic compounds increased during the fermentation and was maximum after 96 h, which inhibited the DPPH radical by 87%. The promising characteristics of the protein and phenolic extracts of the biomass suggested the application in the coating composition for vegetal tissues preservation.

Este trabalho teve como objetivo estudar a utilização de películas, à base de compostos proteicos e fenólicos provenientes de farelo de arroz fermentado, em tomates (Lycopersicum esculentum). Foram realizados testes com: glicerol 3% (v/v); glicerol com extrato fenólico e proteico do farelo de arroz (5%); glicerol com extrato fenólico e proteico da biomassa gerada em 96 hours (5%), e um controle (sem a película). Os tomates revestidos foram mantidos à temperatura ambiente durante 28 dias, sendo determinados, a cada 96 horas, os seguintes aspectos: a perda de massa, o pH e a acidez, os sólidos solúveis totais e os carotenoides. A película elaborada com os extratos da biomassa reduziu os níveis de carotenoides e acidez dos frutos estudados em 17 e 21,1%, respectivamente, em relação ao controle. A película também foi eficiente como barreira ao vapor de água; assim, com perda de massa 57% inferior à do controle, sugere-se que esta poderá ser utilizada como alternativa para conservação desse tecido vegetal.

The aim of this study was to investigate the use of protein-phenolic based coating made from fermented rice bran on cherry tomatoes (Lycopersicum esculentum). Tests were performed with glycerol 3% (v/v), glycerol with protein-phenolic rice bran extract (5%), glycerol with protein-phenolic extract after 96 hours of fermentation (5%), and a control (without coating). The coated cherry tomatoes were kept at room temperature for 28 days. Mass loss, pH and acidity, total soluble solids, and carotenoids were determined every 96 hours. The coating made from the biomass extract reduced the carotenoid and acidity levels in the fruits studied by 17 and 21.1%, respectively, compared to the control. The coating proved an efficient barrier to water vapor with mass loss of 57% less than the control suggesting that it can be used as an alternative for vegetable tissue conservation.

Este trabalho teve por objetivo avaliar a degradação de deoxinivalenol por Aspergillus oryzae e Rhizopus oryzae durante fermentação submersa e correlacioná-la com a atividade de enzimas oxidoredutases. O meio submerso foi constituído por água destilada estéril contaminada com 50 μg de DON e inóculo de 4 × 10(6) esporos.mL-1 de meio das espécies fúngicas Aspergillus oryzae e Rhizopus oryzae, separadamente em cada experimento. A amostragem foi realizada a cada 24 horas de processo para medida da atividade específica da enzima peroxidase, e a cada 48 horas para a determinação dos níveis de DON. Os resultados mostraram que as espécies fúngicas avaliadas possuem capacidade de metabolizar DON, acompanhada de aumento na atividade da enzima oxidativa PO. No intervalo de 48 horas de fermentação, ocorreu a maior atividade específica da enzima peroxidase (ΔABS/minute.μg.protein-1), 800 e 198, correspondendo a maior velocidade de degradação de DON de 10.8 e 12.4 ppb/hour, respectivamente para Rhizopus oryzae e Aspergillus oryzae.

This work aims to evaluate deoxynivalenol degradation by Aspergillus oryzae and Rhizopus oryzae in a submerged fermentation system and to correlate it to the activity of oxydo-reductase enzymes. The submerged medium consisted of sterile distilled water contaminated with 50 μg of DON and 4 × 10(6) spore.mL-1 inoculum of Aspergillus oryzae and Rhizopus oryzae species, respectively in each experiment. Sampling was performed every 24 hours for monitoring the peroxidase specific activity, and every 48 hours for determining mycotoxin levels. Results showed that the fungi species were able to decrease DON levels as the peroxidase activity increased. The 48 hours fermentation interval presented the highest peroxidase specific activity (ΔABS/minute.μg.protein-1), 800 and 198, while the highest DON degradation velocity was 10.8 and 12.4 ppb/hour, respectively in both cases for Rhizopus oryzae and Aspergillus oryzae.