Dynamics of annatto pigment synthesis and accumulation in seeds of Bixa orellana L. revealed by integrated chemical, anatomical, and RNA-Seq analyses.

Bixin is a commercially valuable apocarotenoid pigment found in the seed aril of Bixa orellana. The dynamics and regulation of its biosynthesis and accumulation during seed development remain largely unknown. Here, we combined chemical, anatomical, and transcriptomic data to provide stage-specific resolution of the cellular and molecular events occurring during B. orellana seed development. Seeds at five developmental stages (S1-S5) were used for analysis of bixin content and seed anatomy, and three of them (S1, S3, and S4) were selected for Illumina HiSeq sequencing. Bixin accumulated in large quantities in seeds compared with other tissues analyzed, particularly during the S2 stage, peaking at the S4 stage, and then decreasing slightly in the S5 stage. Anatomical analysis revealed that bixin accumulated in the large central vacuole of specialized cells, which were scattered throughout the developing mesotesta at the S2 stage, but enlarged progressively at later stages, until they occupied most of the parenchyma in the aril. A total of 13 million reads were generated and assembled into 73,381 protein-encoding contigs, from which 312 were identified as containing 1-deoxy-D-xylulose-5-phosphate/2-C-methyl-D-erythritol-4-phosphate (DOXP/MEP), carotenoid, and bixin pathways genes. Differential transcriptome expression analysis of these genes revealed that 50 of them were sequentially and differentially expressed through the seed developmental stages analyzed, including seven carotenoid cleavage dioxygenases, eight aldehyde dehydrogenases, and 22 methyltransferases. Taken together, these results show that bixin synthesis and accumulation in seeds of B. orellana are a developmentally regulated process involving the coordinated expression of DOXP/MEP, carotenoid, and bixin biosynthesis genes.

Análise microbiológica de abóbora minimamente processada e comercializada em feira livre no Município de Itapetinga-BA / Microbiological analysis of minimally processed pumpkin (Cucurbita moschata Duch) in Itapetinga-BA

As condições sanitárias do processamento mínimo de abóboras em feiras livres são consideradas inadequadas, contribuindo, assim, para a contaminação deste tipo de alimento. O presente trabalho teve por objetivo verificar a qualidade microbiológica de abóbora mimimamente processada e comercializada em feira livre no município de Itapetinga-BA. Foram coletadas aleatoriamente seis amostras para realização das análises microbiológicas. Como indicadores do grau de contaminação, foram realizadas as seguintes análises: contagem total, bolores e leveduras, presença de coliformes totais e termotolerantes e salmonela. Os resultados mostraram que 83,33% das amostras apresentaram altos valores para contagem total. Em relação à contagem de bolores e leveduras, as amostras apresentaram contaminação na ordem de 102 a 103 UFC/g de amostra analisada. Todas as amostras estavam impróprias para o consumo de acordo com a legislação brasileira, uma vez que apresentaram altos índices de contaminação por coliformes totais e termotolerantes e resultado positivo para salmonela. Esses resultados indicam a ausência de condições mínimas de higiene sanitária durante as fases de processamento, armazenamento e comercialização deste tipo de alimento, constituindo-se em um grave risco a saúde pública local.

The sanitary conditions of minimal processing of pumpkins in public market places are inadequate, which contribute for food contamination. This work aimed to verify the microbiological quality of minimal processing of pumpkins processed and commercialized in public market places in Itapetinga-BA. Six samples were randomly collected for microbiological analysis. As indicators of the contamination number, the following analyses were performed: plate count, yeasts and molds, total and thermotolerant coliforms and Salmonella. The results showed that 83.33% of the samples presented high plate count. High counts (about 102 a 103 CFU/g) of yeasts and molds were also found in each sample studied. All the samples were found unfit for human consumption according to Brazilian law, since they exhibited high contamination indices of total and thermotolerant coliforms and had positive results for Salmonella. These results indicate inadequate hygienic-sanitary practices during the processing, storage and commercialization of this vegetable, thus becoming a serious risk to public health.