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1.
J Environ Manage ; 114: 8-12, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23201600

RESUMO

Vinasse is a residue that originates from the distillation of fuel alcohol. However, it contains a relative amount of nutrients. The aim of this work was to develop a nutritive solution using vinasse and to compare it with a commercial solution for the cultivation of lettuce, watercress and rocket. Vinasse obtained from juice must was decanted and filtered, followed by chemical analyses of the nutrients. A nutritive solution composed of 10% vinasse supplemented with nutrients was in agreement with the results of the chemical analyses (a similar amount of Furlani's solution). Experiments were then performed in an NFT (Nutrient film technique) system. The treatments used the vinasse solution and a commercial solution constituted from a Yara Fertilizantes(®) product. The height of the aerial part and the number of leaves of the crops were evaluated at 7, 14, 21, 28, 35 and 42 days. In most crops, the results were very similar. The vinasse solution promoted a larger number of leaves in lettuce and the highest aerial part in watercress. For the rocket, there were no significant differences between the two solutions. In conclusion, a nutritive solution was developed using vinasse, and this solution provided suitable growth, which was higher in some cases, for the crops studied herein. This study shows the great potential of this technology as a rational alternative to vinasse disposal.


Assuntos
Fertilizantes/análise , Hidroponia , Resíduos Industriais , Lactuca/crescimento & desenvolvimento , Eliminação de Resíduos Líquidos/métodos
2.
J Cosmet Dermatol ; 21(10): 4205-4214, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35427427

RESUMO

Spirulinais an edible cyanobacterium known worldwide for its high nutritional value, and the interest in its biological activity and bioactive compounds, such as pigments, phenolics, peptides, and lipids, has been increasing. Due to the variety of its properties, the potential application of Spirulina in health is wide, including dermatological area. In a context of increasing demand for natural products and actives in cosmetics, this microorganism becomes a great source. This article aims to review what has already been reported in literature about the potential effects of Spirulina or its isolated compounds in skin, for either aesthetic or clinical purposes. In many studies, Spirulina and its components show a good influence in proliferation of dermal fibroblasts and keratinocytes, extracellular matrix, and collagen production, as well as exerting antioxidant and anti-inflammatory action. Thus, they promote a healthy environment for skin's cells and structure, cooperating for the highlighted anti-aging, photoprotection, and wound-healing effects. Some compounds of the cyanobacterium also exert a lighting property through tyrosinase inhibition. Its antimicrobial action can also be advantageous to skin contributing to anti-acne, antibiofilm, and anti-herpes effects. In face of many attributes and due to its rich composition, Spirulina presents multi-benefits and shows an improvement in the general aspect of skin. However, some applications are still in need of studying and more clinical evidence is necessary.


Assuntos
Cosméticos , Dermatologia , Envelhecimento da Pele , Humanos , Pele , Queratinócitos , Cosméticos/farmacologia , Cosméticos/química
3.
Bioresour Technol ; 320(Pt B): 124370, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33220544

RESUMO

The use of effluents for hydrogen production through dark fermentation is promising because it results in the generation of value-added products and reduction of the effluent's organic load. A low-cost medium using agroindustrial effluents, corn steep liquor (CSL) and cassava processing wastewater (CPW) was evaluated for hydrogen production with microbial consortia (Vir and Gal). Four variables were evaluated for their impact on biohydrogen production through a Plackett Burman design. Subsequently, the significant variables were optimized using a central composite design, resulting in two mathematical models with regression coefficients R2 > 0.92. The maximum yields were validated and resulted in 107 and 83.1 mL of biohydrogen/g COD removed for Vir and Gal, respectively. The lower medium cost for biohydrogen production was 81.5 USD/m3, approximately 80% more economical than some supplemented media. Finally, the scale-up of the biohydrogen production by consortia to 5L resulted in an increase of more than 40%.


Assuntos
Manihot , Meios de Cultura , Fermentação , Hidrogênio , Água , Zea mays
4.
J Hazard Mater ; 404(Pt A): 124059, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33027733

RESUMO

The sugarcane industry is one of the largest in the world and processes huge volumes of biomass, especially for ethanol and sugar production. These processes also generate several environmentally harmful solid, liquid, and gaseous wastes. Part of these wastes is reused, but with low-added value technologies, while a large unused fraction continues to impact the environment. In this review, the classic waste reuse routes are outlined, and promising green and circular technologies that can positively impact this sector are discussed. To remain competitive and reduce its environmental impact, the sugarcane industry must embrace technologies for bagasse fractionation and pyrolysis, microalgae cultivation for both CO2 recovery and vinasse treatment, CO2 chemical fixation, energy generation through the anaerobic digestion of vinasse, and genetically improved fermentation yeast strains. Considering the technological maturity, the anaerobic digestion of vinasse emerges as an important solution in the short term. However, the greatest environmental opportunity is to use the pure CO2 from fermentation. The other opportunities still require continued research to reach technological maturity. Intensifying the processes, the exploration of driving-change technologies, and the integration of wastes through biorefinery processes can lead to a more sustainable sugarcane processing industry.


Assuntos
Microalgas , Saccharum , Biomassa , Etanol , Gases
5.
Bioresour Technol ; 309: 123331, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32283484

RESUMO

Biohydrogen production was evaluated using cassava processing wastewater (CPW) and two microbial consortia (Vir and Gal) from different Brazilian environments. The biohydrogen production was optimized using a Box-Behnken design (T, pH, C/N, and % v/v inoculum). Maximum yields were obtained with hydrolyzed substrate: 4.12 and 3.80 mol H2 / for Vir and Gal, respectively. Similarly, the kinetic parameters µ, k, and q were higher with hydrolyzed CPW in both consortia. The molecular analysis of the consortia through Illumina high-throughput sequencing showed the presence of bacteria from the families Porphyromonadaceae, Clostridiaceae, Ruminococcaceae, and Enterococcaceae. The relative abundance of microbial families varies as fermentation progresses. In both consortia, Clostridiaceae reached the maximum relative abundance in the media between 16 and 24 h, interval in which approximately 90% of the biohydrogen is generated.


Assuntos
Manihot , Águas Residuárias , Reatores Biológicos , Brasil , Fermentação , Hidrogênio , Cinética , Consórcios Microbianos
6.
Bioresour Technol ; 299: 122635, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31882200

RESUMO

The sustainability of a biofuel is severely affected by the technological route of its production. Chemical pretreatment can be considered the traditional method of decomposition of the lignocellulose into its mono and oligomeric units, which can be further bioconverted to ethanol. The evaluation of the recent advances in chemical pretreatments of sugarcane bagasse, especially diluted acids, alkaline, organosolv and ionic liquids, identified the critical points for sustainability. In this context, chemicals recovery and reutilization or their substitution by green solvents, heat and electricity generation through bioenergy, reutilization of water from evaporators, vinasse concentration and the upgrading of lignin were discussed as strategic routes for developing sustainable chemical-based lignocellulose pretreatment. The advances in the technologies that allow greater fractionation of lignocellulosic biomass should be focused on the minimization of the use of natural resources, effluent generation and energy expenditure.


Assuntos
Saccharum , Biomassa , Biotecnologia , Lignina
7.
J Biotechnol ; 323: 17-23, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32569792

RESUMO

Palm oil mill effluent (POME) was tested as a substrate to produce hydrogen by dark fermentation. Two microbial consortia and a pure culture of Clostridium beijerinckii (ATCC 8260) were cultured anaerobically in raw, diluted and hydrolyzed POME to compare biohydrogen production yields in all three media. Experiments were done in 15 mL Hungate tubes containing 5 mL of medium and 1 mL of inoculum. When Clostridium beijerinckii was cultivated at 30 °C in the hydrolyzed POME (P003), containing 7.5 g/L of sucrose, during 8 days of fermentation and 20 % of the inoculum, the maximum biohydrogen production yield was 4.62 LH2/Lmed. Consortium C3 also showed the best production in hydrolyzed POME while consortium C6 achieved its maximum production in raw POME. This effluent is a potential substrate for biohydrogen production.


Assuntos
Clostridium beijerinckii/metabolismo , Fermentação , Hidrogênio/metabolismo , Óleo de Palmeira/metabolismo , Anaerobiose , Fenômenos Químicos , Clostridium beijerinckii/genética , Biologia Computacional , Ácidos Graxos Voláteis/análise , Sequenciamento de Nucleotídeos em Larga Escala , Resíduos Industriais , Consórcios Microbianos
8.
Bioresour Technol ; 300: 122719, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31956056

RESUMO

Microalgae are sources of nutritional products and biofuels. However, their economical processing is challenging, because of (i) the inherently low concentration of biomass in algal cultures, below 0.5%, (ii) the high-water content in the harvested biomass, above 70%; and (iii) the variable intracellular content and composition. Cell wall structure and strength vary enormously among microalgae, from naked Dunaliella cells to robust Haematococcus cysts. High-value products justify using fast and energy-intensive processes, ranging from 0.23 kWh/kg dry biomass in high-pressure homogenization, to 6 kWh/kg dry biomass in sonication. However, in biofuels production, the energy input must be minimized, requiring slower, thermal or chemical pretreatments. Whichever the primary fraction of interest, the spent biomass can be processed into valuable by-products. This review discusses microalgal cell structure and composition, how it affects pretreatment, focusing on technologies tested for large scale or promising for industrial processes, and how these can be integrated into algal biorefineries.


Assuntos
Microalgas , Biocombustíveis , Biomassa , Alimentos
9.
Bioresour Technol ; 292: 121955, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31404754

RESUMO

A new method for CO2 recovery was proposed for cultivation of different microalgae. First, a chemical fixation, where CO2 was injected in alkalinized vinasse to form (bi)carbonate salts, was performed. In addition, biological fixation with CO2-enriched air injection was also accomplished for evaluation of the most promising results. Two bioreactor systems, a stirred-tank reactor and a bubble column reactor, were employed. A higher carbon transfer rate (43.35 g.L-1.h-1) was achieved in the bubble column reactor using NaOH-alkalinized vinasse, along with reductions of the chemical oxygen demand (COD), biological oxygen demand (BOD) and turbidity (TD). This allowed the cultivation of microalgae and cyanobacteria at vinasse concentrations between 70 and 100%, reaching a biomass production of 2.25 g.L-1 in 15 days of culture. The viability of chemical CO2 fixation together with the use of 100% treated vinasse from a bioethanol production unit for microalgae cultivation has been demonstrated in a successfully integrated biorefinery approach.


Assuntos
Microalgas , Análise da Demanda Biológica de Oxigênio , Biomassa , Carbono , Dióxido de Carbono , Gases
10.
Bioresour Technol ; 223: 259-268, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27969577

RESUMO

A successful pilot-scale process for biodiesel production from microbial oil (Biooil) produced by Rhodosporidium toruloides DEBB 5533 is presented. Using fed-batch strategy (1000L working volume), a lipid productivity of 0.44g/L.h was obtained using a low-cost medium composed by sugarcane juice and urea. The microbial oil was used for biodiesel production and its performance was evaluated in diesel engine tests, showing very good performance, especially for the blend B20 SCO, when operating at 2500rpm with lower pollutant emissions (CO2 - 220% less; CO - 7-fold less; NOX 50% less and no detectable HC emissions (<0.11ppm)) when compared with the blends of standard biofuel from soybean oil. A preliminary analysis showed that microbial biodiesel is economically competitive (US$ 0.76/L) when compared to the vegetable biodiesel (US$ 0.81/L). Besides, the yield of biodiesel from microbial oil is higher (4172L/ha of cultivated sugarcane) that represents 6.3-fold the yield of standard biodiesel (661L/ha of cultivated soybean).


Assuntos
Biocombustíveis , Saccharum , Basidiomycota , Lipídeos , Emissões de Veículos
11.
Bioresour Technol ; 159: 380-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24675397

RESUMO

This work evaluates the potential of vinasse (a waste obtained at the bottom of sugarcane ethanol distillation columns) as nutrient source for biohydrogen and volatile fatty acids production by means of anaerobic consortia. Two different media were proposed, using sugarcane juice or molasses as carbon source. The consortium LPBAH1 was selected for fermentation of vinasse supplemented with sugarcane juice, resulting in a higher H2 yield of 7.14 molH2 molsucrose(-1) and hydrogen content in biogas of approx. 31%, while consortium LPBAH2 resulted in 3.66 molH2/molsucrose and 32.7% hydrogen content in biogas. The proposed process showed a rational and economical use for vinasse, a mandatory byproduct of the renewable Brazilian energy matrix.


Assuntos
Biocombustíveis/economia , Biotecnologia/economia , Biotecnologia/métodos , Etanol/farmacologia , Ácidos Graxos Voláteis/biossíntese , Hidrogênio/metabolismo , Consórcios Microbianos/efeitos dos fármacos , Saccharum/química , Reatores Biológicos/microbiologia , Carbono/farmacologia , Ácidos Graxos Voláteis/economia , Hidrogênio/economia , Concentração de Íons de Hidrogênio , Resíduos Industriais , Modelos Teóricos
12.
Braz. arch. biol. technol ; 62: e19180178, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1001423

RESUMO

Abstract We present an improved method of direct transesterification suitable for the quantitative analysis of multiple dry samples for its fatty acid content, using a minimal amount of biomass and reactants. The method features an acid-catalyzed direct alcoholysis of microgram samples of dry biomass; the rationale behind the solvent and reagent proportions chosen is discussed. The method was validated using seven microbial strains with diverse lipid content (Saccharomyces cerevisiae, Saccharomyces boulardii, Candida tropicalis, Haematococcus pluvialis, Chlorella vulgaris, Spirulina platensis and Schizochytrium limacinum), and compared with a macroscale direct transesterification method, and with gravimetric analysis of lipids extracted with solvents. The microscale method showed a conversion of 98.06 ± 0.87% of the lipids, using approximately 3 mg of dry biomass, 1mL of 0.2M H2SO4 dissolved in anhydrous ethanol (the acid is the catalyzer and ethanol the reactant)). The mixture was maintained at 70 °C for 20 h with periodic mixing, and then extracted with 2mL n-heptane and analyzed by GC-FID. The lipid content was then calculated considering dilution and sample mass. This method is effective, reliable, and technically attractive for analytical and comparative purposes.


Assuntos
Biomassa , Etanol/análise , Ácidos Graxos/análise , Triagem/métodos , Gravimetria/métodos
13.
Bioresour Technol ; 101(15): 5892-6, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20350804

RESUMO

The present study aimed at investigating the carbon metabolism in terms of carbon dioxide fixation and its destination in microalgae cultivations. To this purpose, analysis of growth parameters, media of cultivation, biomass composition and productivity and nutrients balance were performed. Four microalgae suitable for mass cultivation were evaluated: Dunaliella tertiolecta SAD-13.86, Chlorella vulgaris LEB-104, Spirulina platensis LEB-52 and Botryococcus braunii SAG-30.81. Global rates of carbon dioxide and oxygen were determinated by a system developed in our laboratory. B. braunii presented the highest CO(2) fixation rate, followed by S. platensis,D. tertiolecta and C. vulgaris (496.98, 318.61, 272.4 and 251.64 mg L(-1)day(-1), respectively). Carbon dioxide fixated was mainly used for microalgal biomass production. Nitrogen, phosphorus (calcium for D. tertiolecta), potassium and magnesium consumption rates (mg gX(-1)) were evaluated for the four microalgae. Biomass composition presented a predominance of proteins but also a high amount of lipids, especially in D. tertiolecta and B. braunii.


Assuntos
Dióxido de Carbono/metabolismo , Eucariotos/classificação , Eucariotos/metabolismo , Biodegradação Ambiental , Estudos de Viabilidade , Especificidade da Espécie
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