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Red Cooked Sauce (RCS) and Red Raw Sauce (RRS) are a mixture of natural crops that have a promising content of bioactive compounds (BC). The aim was to determine the effect of the indigestible fraction (IF) during the colonic fermentation in RCS and RRS by studying the two-way relationship between gut microbiota composition and microbial metabolites produced from BC fermented in the TNO in vitro dynamic model of the human colon (TIM-2). Total BC in undigested and predigested RRS, 957 and 715 mg/100 g DW, respectively, was significantly higher (p < 0.05) than in the RCS, 571 and 406 mg/100 g DW, respectively. Catenibacterium and Holdemanella increased during RCS fermentation, while 13 genera showed a clear positive correlation with most microbial phenolic metabolites. Our findings suggest that the mechanisms, pathways, and enzymes involved in producing microbial metabolites exhibited uniqueness among bacterial taxa, even within shared genus/family classifications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Our hypothesis was that different whole oilseeds included in the diet for steers confined could alter the diversity of rumen bacteria compared to a diet without oilseeds or an exclusively forage diet. It was aimed to evaluate the effects of oilseeds inclusion in the diet on bacterial diversity in the solid fraction of the ruminal content of steers, by gene sequences of the conserved 16S rDNA region. Six crossbred steers castrated males, fitted with ruminal cannula were used in a 6 × 6 Latin square design, using 21-day period. At the start of the experiment, the live weight of the animals averaged 416 ± 9.7 kg (mean ± SD). A total of 2,180,562 16S rDNA sequences were generated for the Bacteria domain by MiSeq sequencing. The bacterial diversity was composed of 24 bacterial phyla, with the most abundant being Firmicutes, Bacteroidetes, and Proteobacteria. Other phyla with less diversity were also identified including Eurychaeota, Tenericutes, SR1 Absconditalbacteria, Synergistetes, Actinobacteria, Saccharibacteria, Elusimicrobia, Cyanobacteria, Verrucomicrobia, Fusobacteria, Lentisphaerae. The similarity in the bacterial community averaged 50% for all the experimental diets. Steers-fed corn silage exhibited a great diversity of bacteria of the Firmicutes phylum. The steers-fed oilseeds in the diet had a great diversity of bacteria from the phylum Bacteroidetes and Proteobacteria. The inclusion of whole oilseeds in the steer diets can alter the rumen bacteria population by up to 50% of total diversity., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

The Cerrado, the largest savanna region in South America, is located in central Brazil. Cerrado physiognomies, which range from savanna grasslands to forest formations, combined with the highly weathered, acidic clay Cerrado soils form a unique ecoregion. In this study, high-throughput sequencing of ribosomal RNA genes was combined with shotgun metagenomic analysis to explore the taxonomic composition and potential functions of soil microbial communities in four different vegetation physiognomies during both dry and rainy seasons. Our results showed that changes in bacterial, archaeal, and fungal community structures in cerrado denso, cerrado sensu stricto, campo sujo, and gallery forest soils strongly correlated with seasonal patterns of soil water uptake. The relative abundance of AD3, WPS-2, Planctomycetes, Thermoprotei, and Glomeromycota typically decreased in the rainy season, whereas the relative abundance of Proteobacteria and Ascomycota increased. In addition, analysis of shotgun metagenomic data revealed a significant increase in the relative abundance of genes associated with iron acquisition and metabolism, dormancy, and sporulation during the dry season, and an increase in the relative abundance of genes related to respiration and DNA and protein metabolism during the rainy season. These gene functional categories are associated with adaptation to water stress. Our results further the understanding of how tropical savanna soil microbial communities may be influenced by vegetation covering and temporal variations in soil moisture.

The Brazilian Cerrado is the second largest biome in Brazil and is considered a biodiversity hotspot. In this work, we compared the bacterial communities in Cerrado soil associated with four types of native vegetation (Cerrado Denso, Cerrado sensu stricto, Campo Sujo, and Mata de Galeria) by ribosomal RNA intergenic spacer analysis, terminal fragment restriction length polymorphism and pyrosequencing. The fingerprinting results were very similar. The bacterial communities of Cerrado Denso and Cerrado sensu stricto grouped together and were distinct from those in Campo Sujo and Mata de Galeria. Pyrosequencing generated approximately 40,000 16S rRNA gene sequences per sample and allowed the identification of 17 phyla in soil samples under Cerrado vegetation. Acidobacteria were dominant in all areas studied with a relative frequency of 40-47 %, followed closely by Proteobacteria accounting for 34-40 % of the sequences. Results from all molecular techniques used suggested that the bacterial communities of Cerrado sensu stricto and Cerrado Denso are very similar to each other, while Campo Sujo forms a separate group, and Mata de Galeria is the most distinct with higher species richness. This is the first extensive study of native Cerrado soil microbiota, an important but endangered biome.

Most studies present in the literature about the rumen microbiome have focused on cattle and sheep. This is the first report of the characterization of the bacterial and archaeal communities present in the liquid and solid-associated fractions of the rumen from free ranging Moxotó breed goats using 16S rRNA gene libraries. PCR was used to amplify the 16S rRNA gene with bacterial and archaeal universal primers and sequences from each library constructed were obtained. Sequences of Bacteria from the phyla Bacteroidetes and Firmicutes were predominant. The overall dominant classes in the rumen were Clostridia and Bacteroidia, which are known to play a role in plant fiber degradation in other ruminants. Unclassified Bacteria accounted for 4.7% of the liquid fraction sequences and 16.4% of the solid fraction sequences. From the archaeal libraries only sequences from the phylum Euryarcheota were identified and were assigned to the class Methanobacteria of the genera Methanobrevibacter and Methanosphaera. A group of Archaea not previously known to be associated with the rumen was identified: uncultured methanogens belonging to the "uncultured marine bacteria" groups II and III. The local water contained high salt concentrations and this may explain the presence of these groups in the Moxotó goat rumen., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

In order to characterize the bacterial community diversity associated to mucus of the coral Mussismilia hispida, four 16S rDNA libraries were constructed and 400 clones from each library were analyzed from two healthy colonies, one diseased colony and the surrounding water. Nine bacterial phyla were identified in healthy M. hispida, with a dominance of Proteobacteria, Actinobacteria, Acidobacteria, Lentisphaerae, and Nitrospira. The most commonly found species were related to the genera Azospirillum, Hirschia, Fabibacter, Blastochloris, Stella, Vibrio, Flavobacterium, Ochrobactrum, Terasakiella, Alkalibacter, Staphylococcus, Azospirillum, Propionibacterium, Arcobacter, and Paenibacillus. In contrast, diseased M. hispida had a predominance of one single species of Bacteroidetes, corresponding to more than 70% of the sequences. Rarefaction curves using evolutionary distance of 1% showed a greater decrease in bacterial diversity in the diseased M. hispida, with a reduction of almost 85% in OTUs in comparison to healthy colonies. integral-Libshuff analyses show that significant p values obtained were <0.0001, demonstrating that the four libraries are significantly different. Furthermore, the sympatric corals M. hispida and Mussismilia braziliensis appear to have different bacterial community compositions according to Principal Component Analysis and Lineage-specific Analysis. Moreover, lineages that contribute to those differences were identified as alpha-Proteobacteria, Bacteroidetes, and Firmicutes. The results obtained in this study suggest host-microbe co-evolution in Mussismilia, and it was the first study on the diversity of the microbiota of the endemic and endangered of extinction Brazilian coral M. hispida from Abrolhos bank.