Brewer's spent grain: characterization and standardization procedure for the enzymatic hydrolysis by Bacillus cereus strain

An important way to reuse agroindustrial by-products and to produce added-value products consists of the production of protein hydrolysates. In the current study, we used Brewer's spent grain (BSG), mainly because of its availability and cost, as a substrate for the enzymatic hydrolysis by Bacillus cereus. First, the physicochemical and microbiological characterization of BSG batches from three varieties was carried out. Furthermore, the optimal fermentation upstream processes for enzymatic hydrolysis by B. cereus were defined. Finally, the ability of B. cereus to hydrolyze different fractions of BSG was analyzed and possible synergistic effects of this bacterium along with other proteolytic bacteria were also investigated. Results showed that the naturally associated microflora was predominantly thermophilic aerobic bacteria and the drying process was the better alternative for BSG preservation. Water, lipids, and ash content differed significantly among the three varieties; however, no statistically significant differences were found in the protein content among them. After BSG characterization studies, the following protocol was set to obtain the fermentation substrate (FS): drying at 60°C for 24-48 H; sieving, grinding, and polyphenol extraction with an alcohol-water solution; and finally autoclaving. A synergistic effect was observed when B. cereus was inoculated with Pseudomonas strains in FS.     

Circadian rhythms in the morphology of neurons in <Emphasis Type="Italic">Drosophila</Emphasis>

Neurons have an enormous capacity to adapt to changing conditions through the regulation of gene expression, morphology, and physiology. In the fruit fly Drosophila melanogaster, this plasticity includes recurrent changes taking place within intervals of a few hours during the day. The rhythmic alterations in the morphology of neurons described so far include changes in axonal diameter, branching complexity, synapse numbers, and the number of synaptic vesicles. The cycles of these changes have larger amplitude when the fly is exposed to light, but they persist in constant darkness and require the expression of the clock genes period and timeless, leading to the concept of circadian plasticity. The molecular mechanisms driving these cycles appear to require the expression of these genes either inside the neurons themselves or in other peripheral pacemaker cells. Loss-of-function mutations in period and timeless not only abolish the morphological rhythms, but also often cause abnormal axonal branching suggesting that circadian plasticity is relevant for the maintenance of normal morphology. Research into whether (1) circadian plasticity is a common feature of neurons in all animals and (2) our own neurons change shape between day and night will be of interest.     

Microbial community of a volcanic mudspring in the Philippines as revealed by 16S rDNA sequence analysis and fluorescence in situ hybridization

Mt. Makiling Mudspring in Laguna, Philippines is a thermophilic, acidophilic environment that previously has been shown to harbor novel microorganisms. We assessed the microbial community that exists at this volcanic mudspring using 16S rRNA-based approaches. DNA was extracted from solfataric soils and sediments taken from Mudspring. The 16S rDNA was PCR amplified using universal (519F-1392R) and archaeal-specific (23FPL-1391R) primer pairs, cloned, and sequenced. Phylogenetic analysis of the cloned 16S rDNA showed that eleven clones clustered with, and therefore related to Sulfolobus tokodaii 7 and two clones clustered with S. solfataricu, S. shibatae and S. islandicus. Three clone sequences were related to those found in thermophilic chalcopyrite (CuFeS₂), a copper sulfuric ore from bioleaching reactors. One clone had low similarity (95% identity) with uncultured archaeon clone KOZ184. Fluorescence in situ hybridization (FISH) analysis revealed that about 71% of the microbial community present in the Mudspring belong to domain Archaea of which 63% were Crenarchaeota and 8% were Euryarchaeota. Seventeen percent (17%) of the population consisted of bacteria as indicated by the positive hybridization with the BACT338 probe, and the remaining 12% are unidentified. This study is the first attempt to use molecular techniques in any environment in the Philippines.     

Comparison of Listeria monocytogenes Exoproteomes from Biofilm and Planktonic State: Lmo2504, a Protein Associated with Biofilms

The food-borne pathogen Listeria monocytogenes is the causative agent of the severe human and animal disease listeriosis. The persistence of this bacterium in food processing environments is mainly attributed to its ability to form biofilms. The search for proteins associated with biofilm formation is an issue of great interest, with most studies targeting the whole bacterial proteome. Nevertheless, exoproteins constitute an important class of molecules participating in various physiological processes, such as cell signaling, pathogenesis, and matrix remodeling. The aim of this work was to quantify differences in protein abundance between exoproteomes from a biofilm and from the planktonic state. For this, two field strains previously evaluated to be good biofilm producers (3119 and J311) were used, and a procedure for the recovery of biofilm exoproteins was optimized. Proteins were resolved by two-dimensional difference gel electrophoresis and identified by electrospray ionization-tandem mass spectrometry. One of the proteins identified in higher abundance in the biofilm exoproteomes of both strains was the putative cell wall binding protein Lmo2504. A mutant strain with deletion of the gene for Lmo2504 was produced (3119Δlmo2504), and its biofilm-forming ability was compared to that of the wild type using the crystal violet and the ruthenium red assays as well as scanning electron microscopy. The results confirmed the involvement of Lmo2504 in biofilm formation, as strain 3119Δlmo2504 showed a significantly (P < 0.05) lower biofilm-forming ability than the wild type. The identification of additional exoproteins associated with biofilm formation may lead to new strategies for controlling this pathogen in food processing facilities.     

A new species of Dasypodidae (Xenarthra: Cingulata) from the late Miocene of northwestern South America: implications in the Dasypodini phylogeny and diversity

A new species of dasypodid armadillo (Xenarthra, Cingulata), Anadasypus aequatorianus, from the late Miocene of Ecuador is described. The remains were collected in sediments of the Letrero Formation, Nabón Basin, which is part of several intermontane basins related to Andean uplift. The genus represents the oldest record of Dasypodini, which also encompasses Propraopus (Pleistocene–early Holocene) and Dasypus (?Miocene–Recent). The new species is based on several osteoderms, which show more derived features than Anadasypus hondanus, from the middle Miocene of Colombia. In order to test the affinities of A. aequatorianus within Dasypodini, we conducted a cladistic analysis of 24 morphological characters for 10 taxa. The most parsimonious tree supports the generic attribution of the new species and places Anadasypus basal to Propraopus and Dasypus, agreeing with the stratigraphic evidence. The faunas from tropical Andean areas differ noticeably from the better-known assemblages of the classic South American sequences. In the case of dasypodines, their geochronological distribution shows that they were historically restricted to tropical and subtropical environments and the main cladogenetic events of the group probably occurred at lower latitudes. In this context, the taxon described herein fills important temporal and geographic gaps of early Neogene armadillos from intertropical areas.http://www.zoobank.org/urn:lsid:zoobank.org:pub:9DC76603-D831-4E68-BE55-90113228E0F4     

Young Chileans' Views of Citizenship: Findings From the First Generation Born After the Reinstitution of Democracy

Through a qualitative methodology, this study examines meanings attached to citizenship, barriers for citizenship, motivations for civic engagement, and aspirations as citizens in a sample (n = 71) of Chilean youth that grew up during the transition to democracy. The meanings youth attached to citizenship include membership, entitlement to rights and responsibilities, active participation, being informed, and voting. Participants perceived that practices of the political class, the economic system, and social disparities are barriers to exercising citizenship. They challenge the principles of a social order they consider unjust and advance proposals for social transformation that claim for social justice, reducing socio-economic disparities, discrimination, and bringing the political class closer to ordinary citizens. Findings reflect critical and cultural notions of citizenship. Contrasting their actual experiences with their aspirations for citizenship, participants feel politically inefficacious as they perceive they lack the power to influence the sociopolitical system. Implications for sociopolitical development and youth policy are discussed.     

Role of ABA and Gibberellin A<Subscript>3</Subscript> on gene expression pattern of sugar transporters and invertases in <Emphasis Type="Italic">Vitis vinifera</Emphasis> cv. Malbec during berry ripening

Sugars are key constituents that affect quality of grape berries, and consequently the grape metabolic profile relevant to wine’s industry. However, enzymes and transporter genes expression involved in sugar transport at different phenological stages are scarcely studied. In addition, little is known about the role of the plant hormones ABA and Gibberellin (GA₃) as endogenous regulators, over the expression pattern of the sugars transporters genes in grapevine. The aim of this study was to analyze the expression pattern of the most relevant sugar transporters and invertases in leaves and berries of grapevine plants cv. Malbec during berry ripening stages and its shift after ABA and GA₃ sprays. In leaves, VvHT1 was the sugar transporter highly expressed, whereas VvHT6 was the most abundant in berries throughout berry ripening. Moreover, VvSUC12 and VvSUC27 were expressed at veraison greater in leaves than in berries, suggesting an active phloem loading at the onset of ripening. Applications of ABA and GA₃ enhanced the expression of VvSUC12 and VvSUC27 in pre-veraison leaves. Furthermore, hormones increased the expression of VvHT2, VvHT3 and VvHT6 in berries at different stages of ripening favoring sugar unloading from phloem. In conclusion, ABA and GA₃ are involved in the long-distance sugar transport from leaves to berries in Vitis vinifera L. cv. Malbec, and their exogenous application could be a suitable strategy to improve the process.     

Assessing large area forest cover products derived from the same imaging source across Victoria,Australia

Forest cover products are an essential tool for land managers and policy makers. They are used at a variety of spatial scales to inform decision‐making and policy across a range of ecosystem drivers and services. This article compares three forest cover products (FCP), all of which were created using Landsat satellite imagery, but using different methodologies and covering different spatial extents that range from global to state. It also explores their use and utility across the state of Victoria, Australia. It asks the question, how interchangeable are the forest cover maps? FCP are also validated against a very high‐resolution reference data set. Overall accuracy was around 89% for the state and national FCP, and 84% for the global FCP. The global map produced the lowest estimate of total forest cover, while estimates obtained by the national and state FCP were similar across the study area. Spatially, differences, however, were apparent. The national forest cover map obtained higher estimates across most of Victoria except in the most arid region which is dominated by low open woodland. While the national and global scale forest cover maps were found to have good diagnostic ability for large area assessment and reporting, their use for land management is not optimal and can lead to gross error.     

<Emphasis Type="Italic">In vitro</Emphasis> morphogenesis and micropropagation of <Emphasis Type="Italic">Aechmea ramosa</Emphasis> var. <Emphasis Type="Italic">ramosa</Emphasis> Mart. ex Schult. f. (Bromeliaceae) from leaf explants

Aechmea ramosa Mart. ex Schult. f. is an endemic bromeliad of the Brazilian Atlantic Forest. The current habitat degradation of this hotspot biome threatens this species, which besides having an important ecological role, is also of invaluable ornamental interest. Plant tissue culture has been used in mass propagation and conservation of various bromeliads. We have established a micropropagation protocol for A. ramosa var. ramosa using leaf explants grown in MS medium supplemented with 2 μM of 1-naphthaleneacetic acid (NAA) and 2 μM of 6-benzylaminopurine (BAP) that showed higher values of shoot induction. NAA and BAP are associated with the production of proteins involved in stress response modulation, metabolic activity, and cell division, the latter being involved in inducing the differentiation of competent cells. After 120 d of culture, each explant presented 28.9 shoots with an average size of 27.8 mm, with no variation in either Stomatal Index or density of the regenerated shoots. Plantlets measuring above 15-mm height were successfully acclimatized, presenting 100% survival rate. Thus, this protocol can be used for mass propagation of A. ramosa, and to supply demand for the market of ornamental plants. Furthermore, it represents an important tool for the conservation of this species and maintenance of an in vitro germplasm.