This study investigated the diversity of yeast species associated with rotting wood in Brazilian Amazonian rainforests. A total of 569 yeast strains were isolated from rotting wood samples collected in three Amazonian areas (Universidade Federal do Amazonas-Universidade Federal do Amazonas [UFAM], Piquiá, and Carú) in the municipality of Itacoatiara, Amazon state. The samples were cultured in yeast nitrogen base (YNB)-D-xylose, YNB-xylan, and sugarcane bagasse and corncob hemicellulosic hydrolysates (undiluted and diluted 1:2 and 1:5). Sugiyamaella was the most prevalent genus identified in this work, followed by Kazachstania.The most frequently isolated yeast species were Schwanniomyces polymorphus, Scheffersomyces amazonensis, and Wickerhamomyces sp., respectively. The alpha diversity analyses showed that the dryland forest of UFAM was the most diverse area, while the floodplain forest of Carú was the least. Additionally, the difference in diversity between UFAM and Carú was the highest among the comparisons. Thirty candidates for new yeast species were obtained, representing 36% of the species identified and totaling 101 isolates. Among them were species belonging to the clades Spathaspora, Scheffersomyces, and Sugiyamaella, which are recognized as genera with natural xylose-fermenting yeasts that are often studied for biotechnological and ecological purposes. The results of this work showed that rotting wood collected from the Amazonian rainforest is a tremendous source of diverse yeasts, including candidates for new species.

Sixteen yeast isolates representing two novel species of the genus Sugiyamaella were obtained from passalid beetles, their galleries and rotting wood collected in three sites of Amazonian Forest in Brazil. Sequence analyses of the ITS-5.8S region and the D1/D2 domains of the large subunit rRNA gene showed that the first species, described here as Sugiyamaella amazoniana f. a., sp. nov. (holotype CBS 18112, MycoBank 847461) is phylogenetically related to S. bonitensis with these species differing by 37 nucleotide substitutions and six gaps in D1/D2 sequences. S. amazoniana is represented by nine isolates obtained from the guts of the passalid beetles Popilius marginatus, Veturius magdalenae, Veturius sinuosus and Spasalus aquinoi, a beetle gallery and rotting wood. The second species, Sugiyamaella bielyi f. a., sp. nov. (holotype CBS 18148, MycoBank 847463), is most phylogenetically related to several undescribed Sugiyamaella species. S. bielyi is described based on seven isolates obtained from the guts of V. magdalenae and V. sinuosus, a beetle gallery and rotting wood. Both species appear to be associated with passalid beetles and their ecological niches in Amazonian biome.

Four isolates of Spathaspora species were recovered from rotting wood collected in two Brazilian Amazonian biomes. The isolates produced unconjugated allantoid asci with a single elongated ascospore with curved ends. Sequence analysis of the ITS-5.8S region and the D1/D2 domains of the large subunit rRNA gene showed that the isolates represent two different novel Spathaspora species, phylogenetically related to Sp. boniae. Two isolates were obtained from rotting wood collected in two different sites of the Amazonian forest in the state of Pará. The name Spathaspora brunopereirae sp. nov. is proposed to accommodate these isolates. The holotype of Spathaspora brunopereirae sp. nov. is CBS 16119T (MycoBank MB846672). The other two isolates were obtained from a region of transition between the Amazonian forest and the Cerrado ecosystem in the state of Tocantins. The name Spathaspora domphillipsii sp. nov. is proposed for this novel species. The holotype of Spathaspora domphillipsii sp. nov. is CBS 14229T (MycoBank MB846697). Both species are able to convert d-xylose into ethanol and xylitol, a trait with biotechnological applications.

A 3 2 factorial design was employed to develop an in vitro digestion method for estimation of Fe bioaccessible fractions in cooked chicken meat. The effects of sample size and the in vitro bioaccessible fractions of this essential element were evaluated. A sample preparation method employing a microwave assisted digestion with dilute nitric acid was used prior to total Fe determination. For the bioacessibility studies, the optimized procedure employed 7.5 g of sample and 6% w/v of an acid pepsin solution. This procedure was applied to two kinds of chicken meat samples: breast and liver. Flame Atomic Absorption Spectrometry was used to determine total and bioaccessible (chyme or soluble portion) levels of iron in the samples. With respect to total Fe content, the bioaccessible fractions of Fe found in these samples were around 23% and 56 %, for breast and chicken liver, respectively. The chicken liver sample showed the highest total (400 ± 10 mg kg-1) and bioaccessible Fe contents (223 ± 18 mg kg-1) and stands out as a good source of this micronutrient.

This work describes the analysis of different chicken tissues (gizzard, heart, and liver) both raw and cooked with seasonings in different types of cooking pots (iron pot, , aluminum pot and hammered aluminum pot) commonly used in Brazil. The samples were decomposed using microwave-assisted digestion with diluted nitric acid; and the contents of Al, Ca, Cu, Fe, Mn and Ni were determined using Microwave Induced Plasma Optical Emission Spectrometry (MIP OES). The Fe content was also determined by Flame Atomic Absorption Spectrometry, and the comparison showed good accuracy of the method. The limits of quantification were below 0.011 mg kg-1, showing adequate detectability. Cooking in the different pots increased the ash and protein contents as well as decreased the moisture content. Box-plot and Principal Components Analysis showed that Ca and Fe contents present the largest variations in the samples, followed by Al and moisture. The variables Al, Cu, Mn, Ni, ash, and protein presented similar behavior after cooking in all different pots. In addition, liver cooked in both iron and hammered aluminum pots presented similar Fe contents, while gizzard and heart showed similar Ca contents.