Induction of Metabolic Changes in Amino Acid, Fatty Acid, Tocopherol, and Phytosterol Profiles by Exogenous Methyl Jasmonate Application in Tomato Fruits.

Methyl jasmonate hormone can stimulate the production of several metabolites responsible for improving fruit quality and nutritional attributes related to human health. In this context, efforts to manipulate tomatoes, such as using hormonal treatment to increase metabolite levels essential to plant growth and human nutrition, have received considerable attention. The aim of this study was to show the impact of metabolic profile on fruit quality and nutritional properties under exogenous methyl jasmonate during fruit ripening. The treatments were performed using 100 ppm of methyl jasmonate and 100 ppm of gaseous ethylene over 24 h. Ethylene emission, fruit surface color and metabolomics analysis were measured at 4, 10, and 21 days after harvest, considering the untreated fruits as control group. Methyl jasmonate induced the production of amino acids-mainly glutamine, glutamic acid and γ-aminobutyric acid (at least 14-fold higher)-and fatty acids-mainly oleic, linoleic, and linolenic acids (at least three-fold higher than untreated fruits); while exogenous ethylene predominantly affected sugar metabolism, increasing the levels of fructose, mannose and glucose to at least two-fold that levels in the untreated fruits. Additionally, methyl jasmonate significantly affected secondary metabolites, inducing by at least 80% the accumulation of α-tocopherol and ß-sitosterol in fully ripe fruits. Our results suggest that the postharvest application of the hormone methyl jasmonate can contribute to the sensory characteristics and increase the nutritional value of the fruits since important changes related to the tomato metabolome were associated with compounds responsible for the fruit quality and health benefits.

Beyond the limits of photoperception: constitutively active PHYTOCHROME B2 overexpression as a means of improving fruit nutritional quality in tomato.

Photoreceptor engineering has recently emerged as a means for improving agronomically beneficial traits in crop species. Despite the central role played by the red/far-red photoreceptor phytochromes (PHYs) in controlling fruit physiology, the applicability of PHY engineering for increasing fleshy fruit nutritional content remains poorly exploited. In this study, we demonstrated that the fruit-specific overexpression of a constitutively active GAF domain Tyr252 -to-His PHYB2 mutant version (PHYB2Y252H ) significantly enhances the accumulation of multiple health-promoting antioxidants in tomato fruits, without negative collateral consequences on vegetative development. Compared with the native PHYB2 overexpression, PHYB2Y252H -overexpressing lines exhibited more extensive increments in transcript abundance of genes associated with fruit plastid development, chlorophyll biosynthesis and metabolic pathways responsible for the accumulation of antioxidant compounds. Accordingly, PHYB2Y252H -overexpressing fruits developed more chloroplasts containing voluminous grana at the green stage and overaccumulated carotenoids, tocopherols, flavonoids and ascorbate in ripe fruits compared with both wild-type and PHYB2-overexpressing lines. The impacts of PHYB2 or PHYB2Y252H overexpression on fruit primary metabolism were limited to a slight promotion in lipid biosynthesis and reduction in sugar accumulation. Altogether, these findings indicate that mutation-based adjustments in PHY properties represent a valuable photobiotechnological tool for tomato biofortification, highlighting the potential of photoreceptor engineering for improving quality traits in fleshy fruits.

Qualidade higiênico-sanitária de pontos de venda e análise microbiológica de alimentos de rua comercializados no campus Umuarama da Universidade Federal de Uberlândia / Sanitary-hygienic quality of sale points and microbiological analysis of street food sold in the Umuarama campus of the Federal University of Uberlândia

Avaliar as condições higiênico-sanitárias de pontos de venda (PV) e analisar a qualidade microbiológica de alimentos de rua comercializados por vendedores ambulantes localizados no Campus Umuarama, Universidade Federal de Uberlândia. Foram investigados no estudo os PV de dez vendedores ambulantes e amostras de alimentos de rua por eles comercializadas. Uma ficha de inspeção higiênico-sanitária (FIHS) foi aplicada nos PV de alimentos antes e três meses após realização de capacitação em boas práticas de fabricação (BPF) de alimentos para os vendedores ambulantes. Alimentos de rua adquiridos nos PV investigados foram analisados para coliformes totais e fecais e Staphylococcus coagulase positiva. Na primeira aplicação da FIHS, 9/10 PV inspecionados foram classificados como ruim (<50% de itens em adequação); um PV apresentou classificação regular (51-75% de adequação), e nenhum PV foi classificado como bom (>75% adequação). Na segunda aplicação da FIHS, 4/10 PV foram classificados como regular, e seis PV continuaram sendo classificados como ruim. Nenhum PV foi classificado como bom. Todas as amostras de alimentos apresentaram contagem de coliformes totais e fecais <3NMP/g de alimento e Staphylococcus coagulase positiva <10UFC/g, ou seja, valores abaixo da faixa de referência dos métodos. Apesar da inadequação higiênico-sanitária dos PV, a prática de rápida comercialização adotada pelos manipuladores dificultou a contaminação microbiológica dos alimentos de rua. Em adição, independentemente do nível de escolaridade e da condição sócioeconômica dos manipuladores, a capacitação em BPF melhorou a condição higiênico-sanitária dos PV, contribuindo para a segurança alimentar e nutricional dos usuários.

To assess the hygienic-sanitary conditions of selling points (SP) and analyze the microbiological quality of street foods sold by street vendors located in the Campus Umuarama, Federal University of Uberlândia. Ten SP of hawkers and street food samples marketed by them, were investigated in the study. A hygienic-sanitary inspection questionnaire (HSIQ) was applied to the food SP before and three months after training course of good manufacturing practices (GMP) for food hawkers. The street foods purchased were analyzed for total and fecal coliforms and Staphylococcus coagulase positive. In the first application of HSIQ, 9/10 SP inspected were classified as poor (<50% of items in adequacy), one SP presented regular classification (51-75% adequacy), and no SP was classified as good (>75 % adequacy). In the second application of the HSIQ, 4/10 SP were classified as regular, and six SP remained classified as poor. No SP was classified as good. All food samples had counts of total and fecal coliforms <3NMP/g food and Staphylococcus coagulase positive <10UFC/g, in other words, values below the reference range of methods. Despite the hygienic-sanitary inadequacy of SP, the practice of rapid sales adopted by food handlers in SP difficult microbiological contamination of street foods. In addition, regardless of education level and socioeconomic status of food handlers, GMP training improved hygienic-sanitary condition of SP, contributing to food security and nutrition of the users.

Fermentabilidade e frutanos da cebola (Allium cepa L. ): estudo in vivo, in vitro e do efeito trófico no intestino grosso / Fermentability of onion fructan (Allium cepa L. ) in vivo, in vitro study and the trophic effect in the large intestine

Os frutanos são carboidratos não-disponíveis, classificados como fibra alimentar solúvel e, também, prebióticos. Chegam intactos no intestino grosso (IG) e sofrem fermentação pela microbiota, fornecendo ácidos graxos de cadeia curta (AGC), gases e biomassa. Os objetivos foram avaliar a fermentação in vivo e in vitro de frutanos da cebola (Allium cepa L.) e seu efeito no intestino grosso de ratos. Durante 38 dias, ratos machos Wistar receberam ração controle (RC) ou suplementada com cebola (10% de frutanos) (RF). Na fermentação in vivo foram avaliados: peso e umidade das fezes, umidade do conteúdo cecal, AGCC, peso total e parede do ceco e pH. Paralelamente, fragmentos do ceco e cólon foram coletados para avaliação morfométrica e proliferação celular. Na fermentação in vitro, as frações indigeríveis das rações (RC e RF) e da cebola foram avaliadas sob diferentes parâmetros, como: pH, AGCC, fermentabilidade e resíduo não fermentado. A fermentação in vivo causou no grupo frutanos 10%, em relação ao controle, os seguintes efeitos: aumento significante do peso e umidade das fezes, da umidade do conteúdo cecal, do peso e parede do ceco e da concentração de AGC e diminuição do pH cecal, no grupo frutanos 10% em relação ao controle. Na fermentação in vitro, houve alterações tanto quantitativas como qualitativas de todos os substratos fermentados. De acordo com todas as variáveis analisadas, a RF apresentou maior fermentabilidade quando comparada com a RC. O grupo frutanos 10% apresentou, no ceco, aumento significante no tamanho das criptas, no número de criptas bifurcadas e no índice metafásico em relação ao controle. No cólon não foi evidenciada qualquer mudança microscópica entre os grupos. Os resultados indicam que a ingestão de frutanos causou mudanças significantes nos parâmetros fermentativos, tanto na fermentação in vivo (ratos) quanto na in vitro e na proliferação celular do ceco...

Fructans are unavailable carbohydrates, c1assified as soluble dietary fiber and prebiotics. They arrive intact in the large intestine (LI) and are fermented by the microbiota. This fermentation mainly produces short chain fatty acids (SCFA), gases and biomass. The objectives were evaluation of the in vitro and in vivo fermentation of onion fructans (Allium cepa L.) and their effect in the large intestine of rats. Male Wistar rats received, for 38 days, control diet (CD) or onion supplemented diet (10% fructans) (FD). In the in vivo fermentation were evaluated: faeces weight and moisture, moisture of caecal content, SCFA, cecum weight and wall and pH. In parallel, fragments of cecum and colon were collected for morphometric and cellular proliferation evaluation. In the in vitro fermentation, non-digestible fractions of CD and FD were evaluated under different parameters, such as: pH, SCFA, fermentability and non-fermentable residues. In vivo fermentation caused, in the 10% fructans group in relation to the control group, the following effects: a significant increase in faeces weight and moisture, in the moisture of caecal content, in cecum weight and wall, in the concentration of SCFA and a decrease in the caecal pH. The in vitro fermentation showed both quantitative and qualitative changes of all fermented substracts. The FD presented greater fermentability when compared to the CD, according to all variables analyzed. The 10% fructans group presented greater depth and fission of caecal crypts and metaphasic index in relation to the control group. No microscopic changes were noticed in the colon between the groups. The results indicated that the ingestion of fructans caused significant changes on the fermentative parameters, both in vivo (rats) and in vitro fermentation, and on cell proliferation in the cecum. In vitro fermentation indicated a possible fermentative behavior of the substracts and the FD had greater fermentability than the CD. These results were confirmed in vivo, once the 10% fructans group presented an increase in the SCFA production compared to the control group. The increase in butyrate might have caused the trophic effect of the cecum, which was noticed by the increase in weight and cellular proliferation.