Environmental scanning electron microscopy (esem) of morinda citrifolia l. (Rubiaceae) colleters

This study describes the colleters of Morinda citrifolia L. (Rubiaceae) by using environmental scanning electron microscopy (ESEM) and energy dispersive x-ray spectroscopy (EDS). Two different developmental stages were characterized as well as the chemical composition of secretion. Colleters are secretory structures that produce mucilage protecting the meristems and leaf primordia against desiccation and/or pathogens. Although these secretory structures are common on Rubiaceae, the results reported here is to the best of our knowledge the first record of colleters on Morinda genus. Colleters are present at the stipule adaxial surface, distributed in lines. These secretory structures are standard type and have no base constriction, differently from all studied species until now. In order to better understand the colleters structure and secretion, two phases were distinguished: a secretory phase and a senescence one. On secretory phase standard type colleters were visualized between leaf primordia and stipule, emerge on secretion. They present smooth surface, however was also possible to observe the contours of secretory cells anticlinal walls. In senescent phase colleters morphology was alternated exhibiting rough surface and blunt to point tips. The surface was rough and on stipule sections was possible to observe idioblasts with raphides bundles. The secretion process of M. citrifolia colleters occurs with the disruption of cuticle and the chemical elements are mostly dominated by carbon and oxygen

Metabolic responses of kombucha consortium fermentation upon ultrasound-processing

This study investigated the effect of ultrasound-assisted fermentation on the metabolic responses of traditional and mango-flavored Kombucha fermentation. The results revealed significant differences in the sugar consumption kinetics of sonicated kombucha. Sucrose consumption over 9 days of fermentation (F1) was higher for control than US-processed kombucha. During the second fermentation (F2), ultrasound processing increased the rates of sucrose consumption as the US processing time increased. US15 increases sucrose consumption by 19 %. Ultrasound favored a higher yield of gluconic, propionic, and isobutyric acids than non-processed kombucha (control) and important changes in the kombucha bioactive compounds profile. Gluconic acid continuously increased to a maximum of 6.74 g/L on D12 (F2) in US15 kombucha compared to 4.17 g/L in non-processed one. The ethanol content was below 0.5 g/L for the sonicated kombucha, reaching its maximum of 0.46 g/L for US7 and 0.25 g/L for US15 kombucha after 28 days of refrigerated storage. Ultrasound-assisted fermentation may cause attenuation of kombucha microbiota and changes in the cellulose fiber, promoting modulation of kombucha consortium metabolism. This study's findings help to develop kombuchas with higher bioactive potential and contribute to optimizing the kombucha fermentation process

Purification, partial characterization and immobilization of a mannose-specific lectin from seeds of Dioclea lasiophylla Mart.

Lectin from the seeds of Dioclea lasiophylla (DlyL) was purified in a single step by affinity chromatography on a Sephadex (R) G-50 column. DlyL strongly agglutinated rabbit erythrocytes and was inhibited by monosaccharides (D-mannose and alpha-methyl-D-mannoside) and glycoproteins (ovalbumin and fetuin). Similar to other Diocleinae lectins, DlyL has three chains, alpha, beta and gamma, with mass of 25,569 +/- 2, 12,998 +/- 1 and 12,588 +/- 1 Da, respectively, and has no disulfide bonds. The hemagglutinating activity of DlyL was optimal in pH 8.0, stable at a temperature of 70 degrees C and decreased in EDTA solution, indicating that lectin activity is dependent on divalent metals. DlyL exhibited low toxicity on Artemia sp. nauplii, but this effect was dependent on the concentration of lectin in solution. DlyL immobilized on cyanogen bromide-activated Sepharose (R) 4B bound 0.917 mg of ovalbumin per cycle, showing the ability to become a tool for glycoproteomics studies