Evaluation of solid and submerged fermentations for the production of cyclodextrin glycosyltransferase by Paenibacillus campinasensis H69-3 and characterization of crude enzyme

Cyclodextrin glycosyltransferase (CGTase) is an enzyme that produces cyclodextrins from starch by an intramolecular transglycosylation reaction. Cyclodextrins have been shown to have a number of applications in the food, cosmetic, pharmaceutical, and chemical industries. In the current study, the production of CGTase by Paenibacillus campinasensis strain H69-3 was examined in submerged and solid-state fermentations. P. campinasensis strain H69-3 was isolated from the soil, which grows at 45 C, and is a Gram-variable bacterium. Different substrate sources such as wheat bran, soybean bran, soybean extract, cassava solid residue, cassava starch, corn starch, and other combinations were used in the enzyme production. CGTase activity was highest in submerged fermentations with the greatest production observed at 48-72 h. The physical and chemical properties of CGTase were determined from the crude enzyme produced from submerged fermentations. The optimum temperature was found to be 70-75 degrees C, and the activity was stable at 55 degrees C for 1 h. The enzyme displayed two optimum pH values, 5.5 and 9.0 and was found to be stable between a pH of 4.5 and 11.0.

Use of hydrotalcites for the removal of toxic anions from aqueous solutions

The removal of toxic anions has been achieved using hydrotalcite via two methods: (1) coprecipitation and (2) thermal activation. Hydrotalcite formed via the coprecipitation method, using solutions containing arsenate and vanadate up to pH 10, are able to remove more than 95% of the toxic anions (0.2 M) from solution. The removal of toxic anions in solutions with a pH of >10 reduces the removal uptake percentage to 75%. Raman spectroscopy observed multiple A1 stretching modes of V−O and As−O at 930 and 810 cm−1, assigned to vanadate and arsenate, respectively. Analysis of the intensity and position of the A1 stretching modes helped to identify the vanadate and arsenate specie intercalated into the hydrotalcite structure. It has been determined that 3:1 hydrotalcite structure predominantly intercalate anions into the interlayer region, while the 2:1 and 4:1 hydrotalcite structures shows a large portion of anions being removed from solution by adsorption processes. Treatment of carbonate solutions (0.2 M) containing arsenate and vanadate (0.2 M) three times with thermally activated hydrotalcite has been shown to remove 76% and 81% of the toxic anions, respectively. Thermally activated hydrotalcite with a Mg:Al ratio of 2:1, 3:1, and 4:1 have all been shown to remove 95% of arsenate and vanadate (25 ppm). At increased concentrations of arsenate and vanadate, the removal uptake percentage decreased significantly, except for the 4:1 thermally activated hydrotalcite. Thermally activated Bayer hydrotalcite has also been shown to be highly effective in the removal of arsenate and vanadate. The thermal activation of the solid residue component (red mud) removes 30% of anions from solution (100 ppm of both anions), while seawater-neutralized red mud removes 70%. The formation of hydrotalcite during the seawater neutralization process removes anions via two mechanisms, rather than one observed for thermally activated red mud.

Pretreatment of sugarcane bagasse by acid-catalysed process in aqueous ionic liquid solutions

A biomass pretreatment process was developed using acidified ionic liquid (IL) solutions containing 10-30% water. Pretreatment of sugarcane bagasse at 130°C for 30min by aqueous 1-butyl-3-methylimidazolium chloride (BMIMCl) solution containing 1.2% HCl resulted in a glucan digestibility of 94-100% after 72h of enzymatic hydrolysis. HCl was found to be a more effective catalyst than H(2)SO(4) or FeCl(3). Increasing acid concentration (from 0.4% to 1.2%) and reaction temperature (from 90 to 130°C) increased glucan digestibility. The glucan digestibility of solid residue obtained with the acidified BMIMCl solution that was re-used for three times was >97%. The addition of water to ILs for pretreatment could significantly reduce IL solvent costs and allow for increased biomass loadings, making the pretreatment by ILs a more economic proposition.

Glycerol carbonate as green solvent for pretreatment of sugarcane bagasse

Background Pretreatment of lignocellulosic biomass is a prerequisite for effective saccharification to produce fermentable sugars. We have previously reported an effective low temperature (90 °C) process at atmospheric pressure for pretreatment of sugarcane bagasse with acidified mixtures of ethylene carbonate (EC) and ethylene glycol (EG). In this study, “greener” solvent systems based on acidified mixtures of glycerol carbonate (GC) and glycerol were used to treat sugarcane bagasse and the roles of each solvent in deconstructing biomass were determined. Results Pretreatment of sugarcane bagasse at 90 °C for only 30 min with acidified GC produced a solid residue having a glucan digestibility of 90% and a glucose yield of 80%, which were significantly higher than a glucan digestibility of 16% and a glucose yield of 15% obtained for bagasse pretreated with acidified EC. Biomass compositional analyses showed that GC pretreatment removed more lignin than EC pretreatment (84% vs 54%). Scanning electron microscopy (SEM) showed that fluffy and size-reduced fibres were produced from GC pretreatment whereas EC pretreatment produced compact particles of reduced size. The maximal glucan digestibility and glucose yield of GC/glycerol systems were about 7% lower than those of EC/ethylene glycol (EG) systems. Replacing up to 50 wt% of GC with glycerol did not negatively affect glucan digestibility and glucose yield. The results from pretreatment of microcrystalline cellulose (MCC) showed that (1) pretreatment with acidified alkylene glycol (AG) alone increased enzymatic digestibility compared to pretreatments with acidified alkylene carbonate (AC) alone and acidified mixtures of AC and AG, (2) pretreatment with acidified GC alone slightly increased, but with acidified EC alone significantly decreased, enzymatic digestibility compared to untreated MCC, and (3) there was a good positive linear correlation of enzymatic digestibility of treated and untreated MCC samples with congo red (CR) adsorption capacity. Conclusions Acidified GC alone was a more effective solvent for pretreatment of sugarcane bagasse than acidified EC alone. The higher glucose yield obtained with GC-pretreated bagasse is possibly due to the presence of one hydroxyl group in the GC molecular structure, resulting in more significant biomass delignification and defibrillation, though both solvent pretreatments reduced bagasse particles to a similar extent. The maximum glucan digestibility of GC/glycerol systems was less than that of EC/EG systems, which is likely attributed to glycerol being less effective than EG in biomass delignification and defibrillation. Acidified AC/AG solvent systems were more effective for pretreatment of lignin-containing biomass than MCC.

Methanesulfonic acid-catalyzed conversion of glucose and xylose mixtures to levulinic acid and furfural

Methanesulfonic acid (MSA) was compared with sulfuric acid for the conversion of glucose and xylose mixtures to produce levulinic acid and furfural. The interactions of glucose and xylose, the predominant sugars found in biomass, were found to influence product yields with furfural degradation reactions enhanced under higher reactant loadings. Fast heating rates allowed maximal yields (>60 mol%) of levulinic acid and furfural to be achieved under short reaction times. Under the range of conditions examined, sulfuric acid produced a slight increase in levulinic acid yield by 6% (P = 0.02), although there was no significant difference (P = 0.11) between MSA and sulfuric acid in levulinic acid formed from glucose alone. The amount and type of the solid residue is similar between MSA and sulfuric acid. As such, MSA is a suitable alternative because its use minimizes corrosion and disposal issues associated with mineral acid catalysts. The heating value of the residue was 22 MJ/kg implying that it is a suitable source of fuel. On the basis of these results, a two-stage processing strategy is proposed to target high levulinic acid and furfural yields, and other chemical products (e.g., lactic acid, xylitol, acetic acid and formic acid). This will result in full utilization of bagasse components.

Effects of mesostructured silica catalysts on the depolymerization of organosolv lignin fractionated from woody eucalyptus

Isolated and purified organosolv eucalyptus wood lignin was depolymerized at different temperatures with and without mesostructured silica catalysts (i.e., SBA-15, MCM-41, ZrO2-SBA-15 and ZrO2-MCM-41). It was found that at 300 oC for 1 h with a solid/liquid ratio of 0.0175/1 (w/v), the SBA-15 catalyst with high acidity gave the highest syringol yield of 23.0% in a methanol/water mixture (50/50, wt/wt). Doping with ZrO2 over these catalysts did not increase syringol yield, but increased the total amount of solid residue. Gas chromatography-mass spectrometry (GC-MS) also identified other main phenolic compounds such as 1-(4-hydroxy-3,5-dimethoxyphenyl)-ethanone, 1,2-benzenediol, and 4-hydroxy-3,5-dimethoxy-benzaldehyde. Analysis of the lignin residues with Fourier transform-Infrared spectroscopy (FT-IR) indicated decreases in the absorption bands intensities of OH group, C-O stretching of syringyl ring and aromatic C-H deformation of syringol unit, and an increase in band intensities associated with the guaiacyl ring, confirming the type of products formed.

Microbial oil production from palm oil empty fruit bunch hydrolysates

This study explores the potential use of empty fruit bunch (EFB) residues from palm oil processing residues, as an alternative feedstock for microbial oil production. EFB is a readily available, lignocellulosic biomass that provides cheaper substrates for oil production in comparison to the use of pure sugars. In this study, potential oleaginous microorganisms were selected based on a multi-criteria analysis (MCA) framework which utilised Analytical Hierarchy Process (AHP) with Preference Ranking Organization Method for Enrichment Evaluation (PROMETHEE) aided by Geometrical Analysis for Interactive Aid (GAIA). The MCA framework was used to evaluate several strains of microalgae (Chlorella protothecoides and Chlorella zofingiensis), yeasts (Cryptococcus albidus and Rhodotorula mucilaginosa) and fungi (Aspergillus oryzae and Mucor plumbeus) on glucose, xylose and glycerol. Based on the results of PROMETHEE rankings and GAIA plane, fungal strains A. oryzae and M. plumbeus and yeast strain R. mucilaginosa showed great promise for oil production from lignocellulosic hydrolysates. The study further cultivated A. oryzae, M. plumbeus and R. mucilaginosa on EFB hydrolysates for oil production. EFB was pretreated with dilute sulfuric acid, followed by enzymatic saccharification of solid residue. Hydrolysates tested in this study are detoxified liquid hydrolysates (LH) and enzymatic hydrolysate (EH).

Evaluation of oil production from oil palm empty fruit bunch by oleaginous micro-organisms

Oil palm empty fruit bunch (EFB) is a readily available, lignocellulosic biomass that has potential to be utilized as a carbon substrate for microbial oil production. In order to evaluate the production of microbial oil from EFB, a technical study was performed through the cultivation of oleaginous micro-organisms (Rhodotorula mucilaginosa, Aspergillus oryzae, and Mucor plumbeus) on EFB hydrolyzates. EFB hydrolyzates were prepared through dilute acid pre-treatment of the biomass, where the liquid fraction of pre-treatment was detoxified and used as an EFB liquid hydrolyzate (EFBLH). The solid residue was enzymatically hydrolyzed prior to be used as an EFB enzymatic hydrolyzate (EFBEH). The highest oil concentrations were obtained from M. plumbeus (1.9 g/L of oil on EFBLH and 4.7 g/L of oil on EFBEH). In order to evaluate the feasibility of large-scale microbial oil production, a techno-economic study was performed based on the oil yields of M. plumbeus per hectare of plantation, followed by the estimation of the feedstock cost for oil production. Other oil palm biomasses (frond and trunk) were also included in this study, as it could potentially improve the economics of large-scale microbial oil production. Microbial oil from oil palm biomasses was estimated to potentially increase oil production in the palm oil industry up to 25%, at a cheaper feedstock cost. The outcome of this study demonstrates the potential integration of microbial oil production from oil palm biomasses with existing palm oil industry (biodiesel, food and oleochemicals production), that could potentially enhance sustainability and profitability of microbial oil production.

Microbial oil production from sugarcane bagasse hydrolysates by oleaginous yeast and filamentous fungi

This study investigated the potential use of sugarcane bagasse as a feedstock for oil production through microbial cultivation. Bagasse was subjected to dilute acid pretreatment with 0.4 wt% H2SO4 (in liquid) at a solid/liquid ratio of 1:6 (wt/wt) at 170 °C for 15 min, followed by enzymatic hydrolysis of solid residue. The liquid fractions of the pretreatment process and the enzymatic hydrolysis process were detoxified and used as liquid hydrolysate (SCBLH) and enzymatic hydrolysate (SCBEH) for the microbial oil production by oleaginous yeast (Rhodotorula mucilaginosa) and filamentous fungi (Aspergillus oryzae and Mucor plumbeus). The results showed that all strains were able to grow and produce oil from bagasse hydrolysates. The highest oil concentrations produced from bagasse hydrolysates were by M. plumbeus at 1.59 g/L (SCBLH) and 4.74 g/L (SCBEH). The microbial oils obtained have similar fatty acid compositions to vegetable oils, indicating that the oil can be used for the production of second generation biodiesel. On the basis of oil yields obtained by M. plumbeus, from 10 million t (wet weight) of bagasse generated annually from sugar mills in Australia, it is estimated that the total biodiesel that could be produced would be equivalent to about 9% of Queensland’s diesel consumption.

Nanoporous carbons from sisal residues and their application in hybrid TiO2/carbon photocatalysts for the removal and degradation of phenol in solution

Tese de doutoramento, Química (Química Tecnológica), Universidade de Lisboa, Faculdade de Ciências, 2016

Fermentação alcoólica de substrato amiláceo e hidrolisado enriquecido com melaço de cana

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Formação de mudas de eucalipto com utilização de lixo orgânico e níveis de irrigação calculados por dois métodos

O estudo das características e das possibilidades de utilização de Resíduo Sólido Urbano (R.S.U.) e mais especificamente de Resíduo Sólido Orgânico Urbano (R.S.O.U.), no Brasil e no Mundo, ainda não produziu informações que possibilitem conhecimentos suficientes para tomadas de decisões que estão sendo exigidas, em razão do crescente volume de resíduos produzidos e os impactos ao meio ambiente. Este trabalho teve o objetivo de estudar o efeito da irrigação associada ao uso de R.S.O.U. para formação de mudas de eucalipto. A pesquisa foi desenvolvida na UNESP, Câmpus de Jaboticabal - SP, sendo adotado como delineamento estatístico o esquema fatorial inteiramente casualizado. Foram utilizados 11 substratos: dois tipos de solos (um Latossolo Vermelho eutrófico e um Latossolo Vermelho distrófico), com e sem adubação química, seis misturas de solo e R.S.O.U., e um utilizando somente R.S.O.U. Sementes de eucalipto var. Citriodora Hooker foram semeadas diretamente em topetes e irrigadas com base em dois métodos de quantificação da água evapotranspirada (tanque Classe A e determinação da massa), em quatro níveis (50; 70; 100 e 130% da evapotranspiração). Os dados coletados e analisados estatisticamente demonstraram que doses acima de 20% de R.S.O.U. na mistura, em solos destinados à produção de mudas de eucalipto, causam efeitos negativos na sobrevivência das plantas.

Diagnóstico sócio-produtivo-econômico da comunidade de catadores de resíduos sólidos do município de Codó-MA: um estudo de caso

The research was carried out in the urban area in Codó-MA, a small city the east part of Maranhão, which has 4,228.000 km2 (IBGE, 2000) and population of 113,768 hab. (IBGE, 2008). The city is also inside Codó-MA micro-region. The city is located in one of the lacking area in Brazil, where the Human Development Index (IDH) is approximately 0,558. It does not present an adequate model of management when talking about solid residue collecting. All of the solid residue produced and collected in the city is stored in an open area that they call lixão , which is located in a residence area in the suburbs. Because of that, a problem that involves public health and environmental areas, we understand it is necessary to investigate the way the local government treats and manages the solid residue collecting, as well as, the social, economical and productive reality of those who are directly involved in the collecting itself, its productive chain of the material, including the handling, transportation and its final destiny. It means a social, productive, economical diagnosis, that in a such way,the local society and the organs of inspection can act in a better way to control the problems that include solid urban residue and come from a bad administration. That way, this work proposes to carry out a study that has as result a diagnosis with feasible alternatives on management, taking as basis, social and economical aspects that compound this productive chain. This work can bring great contributions to a better local reality through the introduction of an integrated and supported system of management of solid residue that includes a selective collecting and the creation of a sanitary area. Taking that into consideration, we can contribute to minimize the environmental impacts in Codó Novo, caused by the garbage

Diagnóstico ambiental da gestão e destinação dos resíduos da construção e demolição (RCD): análise das Construtoras Associadas ao SINDUSCON/RN e empresas coletoras atuantes no município de Parnamirim - RN

Surveys carried out in many Brazilian cities have shown that the CDW Construction and Demolition Waste, in some cases, represent more than 50% of the mass of urban solid residue. Municipalities have struggled to manage in an effective way huge quantities of CDW generated every day and solve the problem of the illegal dumping in an inadequate area, which compromise the quality of life of the population as a whole, thus causing serious problems concerning social-environmental and sanitary. This paperwork was meant it carry out environmental diagnosis of the management and the final destination of the CDW in the city of Parnamirim/RN. The methodology used in this work constituted in the bibliographical research, conducted to give support and fundaments to the subject in question, identification of the main places of legal and illegal dumping, identification of the environmental impacts caused by the irregular deposition of the CDW, valuation of quantity and quality of the CDW and perception according to the Environmental Legislation. The necessary data for the elaboration of this study were carried out through the appliance of questionnaires with open and closed questions, applied to 14 (fourteen) Real Estate developer companies associated with SINDUSCON/RN and 05 companies that deal with the transportation and collection of CDW, formal and informal interviews, exploitational visits and photographical records. The collected data went through a statistic treatment being organized into tables and graphs. The main results obtained from this research show that the interviewees hold a medium knowledge of the specific Environmental Legislation; do not have an effective model of environmental management, resorting to only reusing CDW; that the reusing of CDW is not substantial, as much as the possibility of recycling has a minimal consideration. It was also verified that a considerable percentage of interviewees affirmed to send CDW to illegal and inadequate locations. It is expected that such study can be used as an important tool to subsidize the public administration in the pursuit of solutions which could bring benefits to society and the environment

Crystallization of SiO2-CaO-Na2O Glass Using Sugarcane Bagasse Ash as Silica Source

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)