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dissertação
Uso de Kluyveromyces lactis e Torulaspora delbrueckii com adição de café verde para produção de cervejas IPA
(Universidade Federal de Lavras, 2026-06-30) Silva, André Luiz Ferreira; Duarte, Whasley Ferreira; Abreu, Danilo José Machado de; Santos, Tamara Leite dos; Abreu, Danilo José Machado de
The increasing demand for specialty beers with distinctive sensory characteristics and higher added value has driven research into new biotechnological strategies, including the investigation of non-conventional yeasts and ingredients rich in bioactive compounds. In this context, the present study aimed to evaluate the potential of Kluyveromyces lactis and Torulaspora delbrueckii, used in single and mixed fermentations, combined with the addition of green coffee in the production of India Pale Ale (IPA) beers. Three fermentation treatments were evaluated: B10 (K. lactis), B14 (T. delbrueckii), and co-fermentation (B10+B14). During fermentation and maturation, physicochemical parameters, microbiological, bioactive compounds, antioxidant activity, volatile organic compounds, and sensory characteristics were evaluated. Chemical characterization was performed using high-performance liquid chromatography with diode array detection (HPLC-DAD) and gas chromatography–mass spectrometry (GC-MS), while sensory evaluation included a hedonic test, Check-All-That-Apply (CATA) analysis, and a focus group. The results showed that K. lactis exhibited higher fermentative performance and achieved the highest overall consumer acceptance (6.57 points), whereas T. delbrueckii showed the highest chlorogenic acid retention and antioxidant activity determined by the ABTS assay (28.85 µmol Trolox equivalents/100 mL), demonstrating remarkable functional potential. Co-fermentation resulted in greater aromatic complexity, characterized by the predominance of esters and terpenes associated with fruity, citrus, and floral notes. Furthermore, the agreement between instrumental analyses and sensory evaluation demonstrated a direct relationship between the chemical composition and consumers' sensory perception. The results demonstrate that the use of non-conventional yeasts associated with green coffee represents a promising strategy for developing innovative IPA beers with improved sensory quality, functional potential, and added value, expanding the prospects for biotechnology applications in the brewing industry.
tese
Soil recovery and occasional tillage in regenerative agricultural systems of the Brazilian Cerrado: carbon dynamics, proximal sensing and machine learning
(Universidade Federal de Lavras, 2026-08-25) Sá, Rafaella Tatiane Silva de; Avanzi, Junior Cesar; Barbosa, Samara Martins; Silva, Sérgio Henrique Godinho; Pessoa, Thaís Nascimento; Cerri, Carlos Eduardo Pellegrino
The conversion of native vegetation to intensive agricultural systems in the Brazilian Cerrado has resulted in substantial losses of soil organic carbon, compromising physical properties essential to agroecosystem functioning and generating a carbon debt that poses a challenge to the sustainability of tropical agriculture. Although regenerative agriculture is recognized as a promising strategy for restoring soil health, knowledge gaps remain regarding the recovery of organic carbon fractions following occasional mechanical disturbances and the methods available to monitor these changes. Therefore, this thesis aimed to understand the recovery of soil organic carbon and soil quality in regenerative soybean–cotton systems in the Brazilian Cerrado and to evaluate the potential of integrating proximal sensors, including portable X-ray fluorescence (pXRF), visible and near-infrared diffuse reflectance spectroscopy (Vis-NIR), and Fourier-transform infrared spectroscopy (FTIR), with machine-learning algorithms to predict carbon stocks and soil physical and chemical properties. The study was conducted on Oxisols in the Parecis region of Mato Grosso, using areas of native Cerrado vegetation and agricultural fields under regenerative no-tillage with one, six, and ten years of recovery following a single strategic subsoiling operation performed to alleviate soil compaction. Soil samples collected to a depth of 1.0 m were used to determine total soil organic carbon stocks, particulate organic carbon (POC), mineral-associated organic carbon (MAOC), total nitrogen, and soil physical and chemical properties, in addition to acquiring elemental and spectral information from the sensors. The results showed that carbon recovery differed among carbon fractions and throughout the soil profile. MAOC showed progressive recovery, particularly below 20 cm, approaching or exceeding the values observed under native vegetation in parts of the soil profile. In contrast, POC remained the main component of the carbon debt after ten years of recovery, indicating that its replenishment depends on sustained increases in biomass inputs and the rebuilding of soil structure. Gradual improvements in soil aggregation, porosity, and water retention were also observed, indicating that the recovery of soil functionality is associated with changes in soil structure and carbon stabilization processes. The predictive models showed high performance in estimating carbon stocks, functional organic matter fractions, nitrogen, and several soil physical and chemical properties, demonstrating that the integration of pXRF, FTIR, and Vis-NIR improves predictive capability compared with the use of individual sensors. The results demonstrate that regenerative agriculture promotes the gradual restoration of soil functionality in Cerrado Oxisols and that the combination of proximal sensing and machine learning provides a robust approach for monitoring soil health. By integrating carbon stabilization processes with advanced diagnostic technologies, this thesis advances the understanding of tropical soil regeneration and provides a scientific basis for low-carbon agriculture programs, monitoring, reporting and verification (MRV), environmental certification, and sustainability assessment of regenerative agricultural systems.
Artigo
Breeding sorghum for grain, forage and bioenergy in Brazil
(2026-09-18) Von Pinho, Renzo Garcia; Silva, Eric Vinicius Vieira; Oliveira, Thiago Lucas de; Souza, Vander Fillipe de; Menezes, Cicero Beserra de
Sorghum is a versatile crop used for energy production, human and animal feedings, and raw material for industry. The grain sorghum is the fifth most important cereal worldwide, and Brazil is one of the top 10 sorghum producers. In the last 40 years, the sorghum grain yield in Brazil has increased to 32.70 kg ha-1 year -1. Although this clear evolution, much remains to be done, and sorghum breeders in Brazil still face several challenges. This review discusses the main characteristics of sorghum genetics and breeding, aiming for sorghum improvement for food, fodder, feed, and fuel uses. Herein will be highlighted essential topics related to the genetic control of the main interest traits; conventional sorghum breeding; the development of sorghum lines and hybrids; the use of male-sterility in sorghum breeding; the implication of genotypes-by-environments interaction in sorghum, the use of genome-wide association studies, and genomic prediction to maximize the efficiency of the sorghum breeding programs.
Artigo
Wood stock in neotropical streams: Quantifying and comparing instream wood among biomes and regions
(2022-10-05) Saraiva, Sarah O.; Rutherfurd, Ian D.; KaufmannI, Philip R.; Leal, Cecília G.; Macedo, Diego R.; Pompeu, Paulo S.
Instream wood plays important chemical, physical and ecological functions in aquatic systems, benefiting biota directly and indirectly. However, human activities along river corridors have disrupted wood recruitment and retention, usually leading to reductions in the amount of instream wood. In the tropics, where wood is believed to be more transient, the expansion of agriculture and infrastructure might be reducing instream wood stock even more than in the better studied temperate streams. However, research is needed to augment the small amount of information about wood in different biomes and ecosystems of neotropical streams. Here we present the first extensive assessment of instream wood loads and size distributions in streams of the wet-tropical Amazon and semi-humid-tropical Cerrado (the Brazilian savanna). We also compare neotropical wood stocks with those in temperate streams, first comparing against data from the literature, and then from a comparable dataset from temperate biomes in the USA. Contrary to our expectations, Amazon and Cerrado streams carried similar wood loads, which were lower than the world literature average, but similar to those found in comparable temperate forest and savanna streams in the USA. Our results indicate that the field survey methods and the wood metric adopted are highly important when comparing different datasets. But when properly compared, we found that most of the wood in temperate streams is made-up of a small number of large pieces, whereas wood in neotropical streams is made up of a larger number of small pieces that produce similar total volumes. The character of wood volumes among biomes is linked more to the delivery, transport and decomposition mechanisms than to the total number of pieces. Future studies should further investigate the potential instream wood drivers in neotropical catchments in order to better understand the differences and similarities here detected between biomes and climatic regions.
Artigo
Spatial non-stationarity in the distribution of fish species richness of tropical streams
(2022-11-07) Vieira, Thiago Bernardi; Sánchez-Botero, Jorge Iván; Garcez, Danielle Sequeira Garcez; Lima, Sergio Maia Queiroz; Pavanelli, Carla Simone; Casatti, Lilian; Smith, Welber Senteio; Benedito, Evanilde; Mazzoni, Rosana; Pompeu, Paulo Santos; Agostinho, Carlos Sérgio; Montag, Luciano Fogaça de Assis; Zuanon, Jansen; Aquino, Pedro De Podestà Uchôa de; Cetra, Mauricio; Pena, Simone Almeida; Alexandre, Rafaela Jemely Rodrigues; Oliveira, Andressa Sasha Quevedo Alves; Tejerina-Garro, Francisco Leonardo; Duboc, Luiz Fernando; Pérez-Mayorga, María Angélica; Brejão, Gabriel Lourenço; Mateussi, Nadayca Thayane Bonani; Leitão, Rafael Pereira; Marco Júnior, Paulo de
Diversity gradients are observed for various groups of organisms. For fishes in streams, the water-energy, productivity, and temporal heterogeneity hypotheses can explain richness patterns. The relationship between species diversity and the variables that represent these hypotheses is generally linear and stationary, that is, the effect of each of those variables is constant throughout a geographically defined area. But the assumption of spatial stationarity has not yet been tested on a great number of diversity gradients. Therefore, we aimed to quantify the spatial stationarity in the relationships between fish species richness in small stream (653 streams) located throughout Brazil, and the water-energy, productivity, and temporal heterogeneity hypotheses using a geographically weighted regression—GWR. There was a conspicuous absence of spatial stationarity in fish species richness. Furthermore, water-energy dynamics represented a possible metabolic restriction acting on the community structuring of fish species richness in streams. This mechanism separated the fish fauna into two regions: (i) The Amazonian region, characterized by a stable climate and populations that are less resistant to climatic variation; and (ii) The central region, featured by greater ranges of temperature and fish populations that are resistant to climatic variation.,