Flávio Pinheiro Valois, Kelly Christina Alves Alves Bezerra, Fernanda Paula da Costa Assunção, Lucas Pinto Bernar, Simone Patrícia Aranha Da Paz, Marcelo Costa Santos, Waldeci Paraguassu Feio, Renan Marcelo Pereira Silva, Neyson Martins Mendonça, Douglas Alberto Rocha de Castro, Sergio Duvoisin Junior, Antônio Rafael Quadros Gomes, Victor Ricardo Costa Sousa, Marta Chagas Monteiro, Nélio Teixeira Machado
Subject:
Engineering,
Energy And Fuel Technology
Keywords:
Açaí seeds; Chemical activation; Pyrolysis; Bio-oil; Acidity; Antioxidants, Hydrocarbons.
Online: 28 July 2023 (03:16:52 CEST)
This study explores the impact of temperature and molarity on the pyrolysis of Açaí seeds (Euterpe Oleraceae, Mart.) activated with KOH on the yield of bio-oil, hydrocarbon content of bio-oil, antioxidant activity of bio-oil and chemical composition of aqueous phase. The experiments were carried out at 350, 400, and 450 °C and 1.0 atmosphere, with 2.0 M KOH, and at 450 °C and 1.0 at-mosphere, with 0.5 M, 1.0 M and 2.0 M KOH, in laboratory scale. The composition of bio-oils and aqueous phase determined by GC-MS, while the acid value, a physical-chemical property of fundamental importance in biofuels, of bio-oils and aqueous phases by AOCS methods. The antioxidant activity of bio-oils determined by the TEAC method. The solid phase (biochar) characterized by X-ray diffraction (XRD). The diffractograms identified the presence of Kalicinite (KHCO3) in bio-char, and those higher temperatures favor the formation peaks of Kalicinite (KHCO3). The pyrolysis of Açaí seeds activated with KOH show bio-oil yields from 3.19 to 6.79 (wt.%), aqueous phase yields between 20.34 and 25.57 (wt.%), solid phase yields (coke) between 33.40 and 43.37 (wt.%), and gas yields from 31.85 to 34.45 (wt.%). The yield of bio-oil shows a smooth exponential increase with temperature. The acidity of bio-oil varied between 12.3 and 257.6 mgKOH/g, decreasing exponentially with temperature, while that of aqueous phase between 17.9 and 118.9 mgKOH/g, showing and exponential decay behavior with temperature, demonstrating that higher temperatures favor not only the yield of bio-oil but also bio-oils with lower acidity. For the experiments with KOH activation, the GC-MS of bio-oil identified the presence of hydrocarbons (alkanes, alkenes, cycloalkanes, cycloalkenes, and aromatics) and oxygenates (carboxylic acids, phenols, ketones, and esters). The concentration of hydrocarbons varied between 10.19 to 25.71 (area.%), increasing with temperature, while that of oxygenates from 52.69 to 72.15 (area.%), decreasing with temperature. For the experiments with constant temperature, the concentrations of hydrocarbons in bio-oil in-crease exponentially with molarity, while those of oxygenates decrease exponentially, showing that higher molarities favor the formation of hydrocarbons in bio-oil. The antioxidant activity of bio-oils decreases with increasing temperature, as the content of phenolic compounds decreases, and de-creases with increasing KOH molarity, as higher molarities favors the formation of hydrocarbons. Finally, it can be concluded that chemical activation of Açaí seeds with KOH favors the not only the yield of bio-oil but also the content of hydrocarbons. The study of process variables is of utmost importance in order to clearly assess reaction mechanisms, economic viability and design goals that could be derived from chemically activated biomass pyrolysis processes.
Frédéric Gallardo, Pauline Brochet Brochet P, David Goudenège, João Paulo Silva Nunes, Pauline Andrieux, Barbara Maria Ianni, Amanda Farage Frade, Charles Mady, Ronaldo Honorato Barros Santos, Andreia Kuramoto, Samuel Steffen, Antonio Noedir Stolf, Pablo Pomerantzeff, Alfredo Inacio Fiorelli, Edimar Alcides Bocchi, Cristina Wide Pissetti, Bruno Saba, Fabrício Dias, Marcelo Ferraz Sampaio, Fabio Antônio Gaiotto, José Antonio Marin-Neto, Abílio Fragata, Ricardo Costa Fernandes Zaniratto, Sergio Siqueira, Giselle De Lima Peixoto, Fernando Bacal, Paula Buck, Rafael Ribeiro Almeida, Hui Tzu Lin-Wang, André Schmidt, Mario Hiroyuki Hirata, Eduardo Antonio Donadi, Alexandre Costa Pereira, Virmondes Rodrigues Junior, Martino Martinelli, Michel Naslavsky, Jorge Kalil, Vincent Procaccio, Edecio Cunha-Neto, Christophe Chevillard
Subject:
Biology And Life Sciences,
Parasitology
Keywords:
chagas; cardiomyopathy; mitochondria; haplgroups; variants; copy-number
Online: 13 October 2023 (03:03:37 CEST)
Cardiomyopathies are major causes of heart failure. Chagas disease (CD) is caused by the parasite Trypanosoma cruzi, and it is endemic in Central, South America. Thirty percent of the cases evolve into chronic cardiomyopathy (CCC) with worse prognosis as compared with other cardiomyopathies. In vivo bioenergetic analysis and ex vivo proteomic analysis of myocardial tissues highlighted worse mitochondrial dysfunction in CCC, and previous studies identified nuclear-encoded mitochondrial gene variants segregating with CCC. Here, we assessed the role of the mitochondrial genome through mtDNA copy number variations and mtDNA haplotyping and sequencing from heart or blood tissues of severe, moderate CCC and asymptomatic/indeterminate Chagas disease as well as healthy controls as an attempt to help decipher mitochondrial-intrinsic genetic involvement in Chagas disease development. We have found that mtDNA copy number was significantly lower in CCC than in heart tissue from healthy individuals, while blood mtDNA content was similar among asymptomatic Chagas disease, moderate and severe CCC patients. MtDNA haplogrouping study has indicated that African haplogroups were over represented in the Chagas subject groups in comparison with Brazilian healthy individuals. The European lineage is associated to protection against cardiomyopathy and the macro haplogroup H is associated with increased risk towards CCC. By mitochondria DNA sequencing, 84 mtDNA-encoded protein sequence pathogenic variants were associated with CCC. Among them, two variants were associated to left ventricular non-compaction and two to hypertrophic cardiomyopathy. The finding that mitochondrial protein-coding SNPs and mitochondrial haplogroups associate with risk of evolving to CCC is consistent with a key role of mitochondrial DNA in the development of Chronic Chagas disease Cardiomyopathy.