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BACKGROUND: Ganoderma spp. are a great source of bioactive molecules. The production and recovery of bioactive molecules vary according to strain, growth substrate, and extraction solution. Variations in protease and their inhibitors in basidiomata from a commercial strain (G. lingzhi) and an Amazonian isolate (Ganoderma sp.) cultivated in Amazonian lignocellulosic wastes and extracted with different solutions are plausible and were investigated in our study. METHODS: Basidiomata from cultivation in substrates based on açaí seed, guaruba-cedro sawdust and three lots of marupá sawdust were submitted to extraction in water, Tris-HCl, and sodium phosphate. Protein content, proteases, and protease inhibitors were estimated through different assays. The samples were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Fourier transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR). RESULTS: Tris-HCl provided higher protein extraction from Ganoderma sp. and higher caseinolytic, gelatinolytic, and fibrinolytic activity for G. lingzhi cultivated in açaí. Water extracts of Ganoderma sp., in general, exhibited higher trypsin and papain inhibitor activities compared to G. lingzhi. Extracts in Tris-HCl and sodium phosphate showed more intense protein bands in SDS-- PAGE, highlighting bands of molecular weights around 100, 50, and 30 kDa. FTIR spectra showed patterns for proteins in all extracts, with variation in transmittance according to substrate and extractor. CONCLUSION: Water extract from Amazonian Ganoderma sp. cultivated in marupá wastes are promising as a source of protease inhibitors, while the Tris-HCL extract of G. lingzhi from açaí cultivation stands out as a source of proteases with fibrinolytic, caseinolytic, and gelatinolytic activities.

RESUMO

Bacteria and yeast are being intensively used to produce biofuels and high-added-value products by using plant biomass derivatives as substrates. The number of microorganisms available for industrial processes is increasing thanks to biotechnological improvements to enhance their productivity and yield through microbial metabolic engineering and laboratory evolution. This is allowing the traditional industrial processes for biofuel production, which included multiple steps, to be improved through the consolidation of single-step processes, reducing the time of the global process, and increasing the yield and operational conditions in terms of the desired products. Engineered microorganisms are now capable of using feedstocks that they were unable to process before their modification, opening broader possibilities for establishing new markets in places where biomass is available. This review discusses metabolic engineering approaches that have been used to improve the microbial processing of biomass to convert the plant feedstock into fuels. Metabolically engineered microorganisms (MEMs) such as bacteria, yeasts, and microalgae are described, highlighting their performance and the biotechnological tools that were used to modify them. Finally, some examples of patents related to the MEMs are mentioned in order to contextualize their current industrial use.

RESUMO

BACKGROUND: Orange bagasse (OB) is an agroindustrial residue of great economic importance that has been little explored for the extraction of cellulose. The present study aimed to investigate different combinations of chemical (sodium hydroxide, peracetic acid and alkaline peroxide) and physical (autoclaving and ultrasonication) treatments performed in one-step processes for cellulose extraction from OB and to characterize the materials obtained according to their composition, morphology, crystallinity and thermal stability. RESULTS: The processing yields ranged from 140 to 820 g kg-1 , with a recovery of 720-1000 g kg-1 of the original cellulose. Treatments promoted morphological changes in the fiber structure, resulting in materials with higher porosity, indicating partial removal of the noncellulosic fractions. The use of combined chemical treatments (NaOH and peracetic acid) with autoclaving was more efficient for obtaining samples with the highest cellulose contents. CONCLUSION: Therefore, ACSH (processed by autoclaving with NaOH) was the most effective one-step treatment, resulting in 71.1% cellulose, 0% hemicellulose and 19.0% lignin, with a crystallinity index of 42%. The one-step treatments were able to obtain materials with higher cellulose contents and yields, reducing reaction times and the quantity of chemical reagents employed in the overall processes compared to multistep conventional processes. © 2020 Society of Chemical Industry.

Assuntos

RESUMO

The objective of this study was to evaluate the combination of physical and chemical pretreatments of wheat bran (WB) and oat hulls (OH) to obtain fermentable sugars and a residual solid fraction with increased susceptibility to enzymatic hydrolysis. High-pressure steam in an autoclave and ultrasonication were employed as pretreatments, and for both processes, WB and OH were treated with sulfuric acid (H2SO4), neutral medium (H2O) and sodium hydroxide (NaOH). Autoclave high-pressure steam in an acid medium was the most effective for the release of sugars (total sugars, xylose and glucose) from liquid hydrolysates and for the modification of the residual solid fraction. The cellulose content of the WB residual solid fraction increased from 7.19 to 39.17%, the lignin fraction of WB decreased from 6.40 to 3.21%, the cellulose content of OH increased from 31.16 to 61.53%, and lignin fraction of OH decreased from 18.12 to 7.24%, resulting in materials more susceptible to enzymatic hydrolysis.

Assuntos

RESUMO

The briquetting process consists of lignocellulosic residues densification in solid biofuel with high calorific value denominated briquette. Coffee crop is one of the most important Brazilian commodities and according to the cultural practices produces plant residues in different amounts. The zero harvest system in coffee crop is based in pruning of plagiotropic branches in alternated years to make possible to concentrate the harvest and to avoid coffee biannual production. The aim of the present work was to verify the viability of briquette production using the biomass waste obtained by zero harvest system. The treatments were composed of briquetting process: 1) coffee rind; 2) mixture of branches and leaves; 3) 25% of coffee rind + 75% of branches and leaves; 4) 75% of coffee rind + 25% of branches and leaves; 5) 50% of coffee rind + 50% of branches and leaves; 6) 40% of coffee rind + 60% of branches and leaves. The mixtures were realized in v/v base, milled to produce 5-10 mm particles and were briqueted with 12% of humidity. The C-teor of briquettes produced ranged from 41.85 to 43. 84% and sulphur teor was below 0.1%. The calorific value of briquettes produced ranged from 3,359 to 4, 028 Kcal/ kg and the ashes were below 6%. The isolated use of coffee rind or branches and leaves, as well the mixtures of coffee rind with 50% or more of branches and leaves allow the production of briquetteswith calorific value around 4,000 Kcal/ kg which is within the quality parameters. The briquetting ofcoffee crop wastes is viable and sustainable energetically.(AU)

O processo de briquetagem consiste na densificação de resíduos lignocelulósicos em biocombustível sólido, de alto poder calorífico, denominado briquete. A cultura do café, importante commodity brasileira, produz resíduos culturais em quantidades diferentes dependendo dos tratos culturais. O Sistema Safra Zero de condução da lavoura é baseado em podas dos ramos plagiotrópicos em anos alternados, possibilitando a concentração da produção e evitando a bianualidade de produção cafeeiro. O presente trabalho teve por objetivo verificar a viabilidade de produção de briquetes a partir do emprego dos restos culturais obtidos no sistema safra zero. Os tratamentos consistiram da briquetagem de: 1) casca de café, 2) mistura de galhos e folhas; 3) 25% de casca de café + 75% de galhos e folhas; 4) 75% casca de café + 25% de galhos e folhas; 5) 50% casca de café + 50% de galhos e folhas; 6) 40% casca de café + 60% de galhos e folhas. Todas as misturas foram realizadas na base de v/v, sendo moídas gerando partículas de 5 a 10 mm, que ao atingirem 12% de umidade, foram processados na forma de briquetes. O teor de carbono dos briquetes produzidos variou de 41,85 a 43,84% e o de enxofre ficou abaixo de 0,1%. O poder calorífico dos briquetes produzidos variou de 3.359,4 a 4.028,3 kcal kg-1 e as cinzas ficaram abaixo de 6%. O uso de casca de café ou galhos e folhas de forma isolada, bem como a mistura de casca de café com 50% ou mais de galhos folhas permitem a produção de briquetes compode calorífico superior (PCS) em torno dos 4.000 Kcal kg-1, que se encontra dentro dos parâmetros dequalidade. A briquetagem de resíduos da lavoura cafeeira é viável e sustentável energeticamente.(AU)

Assuntos

RESUMO

The briquetting process consists of lignocellulosic residues densification in solid biofuel with high calorific value denominated briquette. Coffee crop is one of the most important Brazilian commodities and according to the cultural practices produces plant residues in different amounts. The zero harvest system in coffee crop is based in pruning of plagiotropic branches in alternated years to make possible to concentrate the harvest and to avoid coffee biannual production. The aim of the present work was to verify the viability of briquette production using the biomass waste obtained by zero harvest system. The treatments were composed of briquetting process: 1) coffee rind; 2) mixture of branches and leaves; 3) 25% of coffee rind + 75% of branches and leaves; 4) 75% of coffee rind + 25% of branches and leaves; 5) 50% of coffee rind + 50% of branches and leaves; 6) 40% of coffee rind + 60% of branches and leaves. The mixtures were realized in v/v base, milled to produce 5-10 mm particles and were briqueted with 12% of humidity. The C-teor of briquettes produced ranged from 41.85 to 43. 84% and sulphur teor was below 0.1%. The calorific value of briquettes produced ranged from 3,359 to 4, 028 Kcal/ kg and the ashes were below 6%. The isolated use of coffee rind or branches and leaves, as well the mixtures of coffee rind with 50% or more of branches and leaves allow the production of briquetteswith calorific value around 4,000 Kcal/ kg which is within the quality parameters. The briquetting ofcoffee crop wastes is viable and sustainable energetically.

O processo de briquetagem consiste na densificação de resíduos lignocelulósicos em biocombustível sólido, de alto poder calorífico, denominado briquete. A cultura do café, importante commodity brasileira, produz resíduos culturais em quantidades diferentes dependendo dos tratos culturais. O Sistema Safra Zero de condução da lavoura é baseado em podas dos ramos plagiotrópicos em anos alternados, possibilitando a concentração da produção e evitando a bianualidade de produção cafeeiro. O presente trabalho teve por objetivo verificar a viabilidade de produção de briquetes a partir do emprego dos restos culturais obtidos no sistema safra zero. Os tratamentos consistiram da briquetagem de: 1) casca de café, 2) mistura de galhos e folhas; 3) 25% de casca de café + 75% de galhos e folhas; 4) 75% casca de café + 25% de galhos e folhas; 5) 50% casca de café + 50% de galhos e folhas; 6) 40% casca de café + 60% de galhos e folhas. Todas as misturas foram realizadas na base de v/v, sendo moídas gerando partículas de 5 a 10 mm, que ao atingirem 12% de umidade, foram processados na forma de briquetes. O teor de carbono dos briquetes produzidos variou de 41,85 a 43,84% e o de enxofre ficou abaixo de 0,1%. O poder calorífico dos briquetes produzidos variou de 3.359,4 a 4.028,3 kcal kg-1 e as cinzas ficaram abaixo de 6%. O uso de casca de café ou galhos e folhas de forma isolada, bem como a mistura de casca de café com 50% ou mais de galhos folhas permitem a produção de briquetes compode calorífico superior (PCS) em torno dos 4.000 Kcal kg-1, que se encontra dentro dos parâmetros dequalidade. A briquetagem de resíduos da lavoura cafeeira é viável e sustentável energeticamente.

Assuntos

RESUMO

Lignocellulosic residues, such as sugarcane bagasse, rice and oat straw and forest cuttings, are abundant and inexpensive sources of carbohydrates (cellulose and hemicellulose) with potential application in several conversion processes. Xylose, the predominant sugar in the hemicellulose fraction can be converted to xylitol. Xylitol is a polyol with some interesting properties that can make it an important product for the food and pharmaceutical industry. It is a compound with sweetness similar to that sucrose, is non-cariogenic, tolerated by diabetics and recommended for obese people. This polyol is currently produced by chemical catalysis of the xylose from lignocellulosic residues. However, this process needs expensive purification steps to obtain pure xylitol. Alternatively, it can be produced by biotechnological methods, using microorganisms, specially yeasts. These processes consist of hemicellulosic hydrolysate fermentation from agro-industrial residues, wich could compete with the traditional chemical method. The present work aims the accomplishment of a review about xylitol detaching the structural aspects, ways of attainment and applications; main hemicellulosic substrates used in its production; acid hydrolysis and treatment of the hemicellulosic hydrolysate for use as substrate to produce xylitol by microbial way.

Resíduos lignocelulósicos tais como bagaço de cana-de-açúcar, palha de arroz, casca de aveia e resíduos florestais representam fontes abundantes e não dispendiosas de carboidratos (celulose e hemicelulose) com potencial aplicação em processos de conversão química ou microbiana em produtos de interesse comercial. Xilose, o açúcar predominante na fração hemicelulósica pode ser convertido em xilitol. O xilitol é um poliol com propriedades físico-química importantes para as indústrias alimentícia e farmacêutica. É um composto com doçura semelhante à da sacarose, anticariogênico, tolerado por diabéticos e recomendado para pessoas obesas. Este poliol é produzido ,em grande escala, por hidrogenação catalítica da xilose presente em hidrolisados lignocelulósicos, porém as soluções obtidas por este processo requerem onerosos passos de purificação para obtenção do xilitol puro. Alternativamente, pode ser produzido por métodos biotecnológicos utilizando leveduras e/ou enzimas. Tais processos consistem na fermentação de hidrolisados hemicelulósicos de resíduos agroindustriais, e podem competir com o tradicional processo químico. O presente trabalho teve como objetivo a realização de uma revisão bibliográfica sobre xilitol destacando os aspectos estruturais, as vias de obtenção e aplicações, principais substratos hemicelulósicos empregados em sua produção, hidrólise ácida e tratamento do hid

RESUMO

Lignocellulosic residues, such as sugarcane bagasse, rice and oat straw and forest cuttings, are abundant and inexpensive sources of carbohydrates (cellulose and hemicellulose) with potential application in several conversion processes. Xylose, the predominant sugar in the hemicellulose fraction can be converted to xylitol. Xylitol is a polyol with some interesting properties that can make it an important product for the food and pharmaceutical industry. It is a compound with sweetness similar to that sucrose, is non-cariogenic, tolerated by diabetics and recommended for obese people. This polyol is currently produced by chemical catalysis of the xylose from lignocellulosic residues. However, this process needs expensive purification steps to obtain pure xylitol. Alternatively, it can be produced by biotechnological methods, using microorganisms, specially yeasts. These processes consist of hemicellulosic hydrolysate fermentation from agro-industrial residues, wich could compete with the traditional chemical method. The present work aims the accomplishment of a review about xylitol detaching the structural aspects, ways of attainment and applications; main hemicellulosic substrates used in its production; acid hydrolysis and treatment of the hemicellulosic hydrolysate for use as substrate to produce xylitol by microbial way.

Resíduos lignocelulósicos tais como bagaço de cana-de-açúcar, palha de arroz, casca de aveia e resíduos florestais representam fontes abundantes e não dispendiosas de carboidratos (celulose e hemicelulose) com potencial aplicação em processos de conversão química ou microbiana em produtos de interesse comercial. Xilose, o açúcar predominante na fração hemicelulósica pode ser convertido em xilitol. O xilitol é um poliol com propriedades físico-química importantes para as indústrias alimentícia e farmacêutica. É um composto com doçura semelhante à da sacarose, anticariogênico, tolerado por diabéticos e recomendado para pessoas obesas. Este poliol é produzido ,em grande escala, por hidrogenação catalítica da xilose presente em hidrolisados lignocelulósicos, porém as soluções obtidas por este processo requerem onerosos passos de purificação para obtenção do xilitol puro. Alternativamente, pode ser produzido por métodos biotecnológicos utilizando leveduras e/ou enzimas. Tais processos consistem na fermentação de hidrolisados hemicelulósicos de resíduos agroindustriais, e podem competir com o tradicional processo químico. O presente trabalho teve como objetivo a realização de uma revisão bibliográfica sobre xilitol destacando os aspectos estruturais, as vias de obtenção e aplicações, principais substratos hemicelulósicos empregad