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When the cocoa pod husk (CPH) is used and processed, two types of flour were obtained and can be differentiated by particle size, fine flour (FFCH), and coarse flour (CFCH) and can be used as a possible reinforcement for the development of bio-based composite materials. Each flour was obtained from chopping, drying by forced convection, milling by blades, and sieving using the 100 mesh/bottom according to the Tyler series. Their physicochemical, thermal, and structural characterization made it possible to identify the lower presence of lignin and higher proportions of cellulose and pectin in FFCH. Based on the properties identified in FFCH, it was included in the processing of thermoplastic starch (TPS) from the plantain pulp (Musa paradisiaca) and its respective bio-based composite material using plantain peel short fiber (PPSF) as a reinforcing agent using the following sequence of processing techniques: extrusion, internal mixing, and compression molding. The influence of FFCH contributed to the increase in ultimate tensile strength (7.59 MPa) and higher matrix-reinforcement interaction when obtaining the freshly processed composite material (day 0) when compared to the bio-based composite material with higher FCP content (30%) in the absence of FFCH. As for the disadvantages of FFCH, reduced thermal stability (323.57 to 300.47 °C) and losses in ultimate tensile strength (0.73 MPa) and modulus of elasticity (142.53 to 26.17 MPa) during storage progress were identified. In the case of TPS, the strengthening action of FFCH was not evident. Finally, the use of CFCH was not considered for the elaboration of the bio-based composite material because it reached a higher lignin content than FFCH, which was expected to decrease its affinity with the TPS matrix, resulting in lower mechanical properties in the material.

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We investigated whether highly available organic residues in Brazil can be used as substrates for the production of the oyster mushroom Pleurotus ostreatus, instead of the conventional cultivation using the eucalyptus sawdust substrate. We assessed the mushroom yield on 13 substrates, of which 12 were formulated with different concentrations of organic residues and one with pure eucalyptus sawdust, and verified whether the raw material used in the substrate formula and the concentration of such alternative residues influenced their biological efficiencies. Substrates containing eucalyptus bark resulted in higher mushroom yield than those containing eucalyptus sawdust, which generally resulted in similar mushroom yield to the remaining formulas. Moreover, the raw material and the concentration of each residue affected the biological efficiency of the substrates. We show that the conventional substrate for P. ostreatus can be replaced by substrates easily accessible to producers without loss in productivity. Furthermore, that the concentration of these mixtures affects the mushroom productivity and should be considered when formulating the growth medium.

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In the present research, soybean straw was used to prepare nanocellulose (NC) via a ball mill, in different milling times (6, 9, and 12 h) and in-situ modified with an anionic surfactant. NCs were characterized for their chemical structure, surface composition, dimension and stability, morphology, crystalline structure, and thermal stability. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy results indicated a cellulosic structure for NCs and a physical interaction due to the electronic attractions between nanocellulose hydroxyls and surfactant end chain groups. The dynamic light scattering, Zeta potential, and transmission electron microscopy indicated that the in situ modified samples showed smaller sizes and good electrostatic stability. Besides, while ball mill resulted in nanofibers, the in situ modified-NC showed a nanocrystal shape, indicating that the surfactant alters the milling process and cellulose scale reduction. The modified-NC showed lower crystallinity and crystal size than unmodified nanocelluloses due to the surfactant chains' addition and influence during the milling process. The modified-NC showed slightly superior thermal stability. The NC-12S showed smaller particle sizes, high electrostatic, and thermal stability and indicated that 12 h is adequate to prepare modified nanocellulose via in situ modification. The prepared samples could be potentially used as coatings, emulsifiers, and nanocomposites reinforcing agents.

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An integral bioprocess to produce lactic acid (LA) from banana peel (BP) was studied. Oxidases produced by Trametes versicolor and hydrolases produced by Aspergillus flavipes and Aspergillus niger saccharified BP at optimal conditions: 230 rpm, 66 g/L BP, and 73.5% (v/v) of enzymatic crude extract (using equal quantities of the enzymatic extracts). At bioreactor scale (1 L), the joint action of oxidases and hydrolases released 18 g/L of reducing sugars (RS) after 24 h (60% corresponded to glucose), consuming the BP polysaccharides. Lactobacillus delbrueckii fermented the released RS, producing 10 g/L of LA; while in the sequential fermentation (inoculating L. delbrueckii after saccharification), 28 g/L of LA were produced, observing an apparent decrease in feedback inhibition of hydrolases below 1.5 g/L of RS. This process is susceptible for upscaling to produce high LA concentrations and represents a platform to utilize agroindustrial wastes to obtain value-added products.

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Production of biochar from organic wastes promises to be an interesting source of plant nutrients, thus reducing pressure on natural resources. To assess the effect of biochar prepared from wastes filtration materials on the growth and production of common bean (Phaseolus vulgaris L.), three simultaneous greenhouse experiments were conducted with three different biochar from organic wastes (rice husk, sawdust, and sorghum silage) using as filtration material for swine biofertilizer. In each experiment the treatments consisted of the addition of five different biochar concentrations (0%, 2.5%, 5%, 7.5%, and 10% v/v), arranged in a completely random design, with four repetitions. Application of biochar increased the root dry mass, shoot dry mass, grain dry mass, number of pods and number of grains. These results indicated that biochar contributed significantly to the growth and production of common bean plants.(AU)

A produção de biochar a partir de resíduos orgânicos pode ser uma estratégia agronômica interessante como fonte de nutrientes para as plantas, diminuindo assim, a pressão sobre os recursos naturais. Com o objetivo de avaliar o efeito de biocarvões, produzidos de materiais filtrantes descartados, no crescimento e produção de feijão (Phaseolus vulgaris L.), conduziram-se simultaneamente três experimentos em casa de vegetação. Cada um dos experimentos foi representado pela aplicação de um biochar, os quais foram produzidos a partir de resíduos orgânicos de casca de arroz, serragem e restos de silagem de sorgo, utilizados como material filtrante para o biofertilizante suíno; e os tratamentos avaliados consistiram na adição de cinco níveis de biocarvão, isto é, 0, 2,5%, 5% 7,5% e 10% v/v. Nos três experimentos a aplicação de biochar aumentou a massa seca da raiz, massa seca da parte aérea, massa seca de grãos, número de vagens e número de grãos. Esses resultados indicam que os biochars contribuíram significativamente para o crescimento e produção do feijoeiro.(AU)

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ABSTRACT: Production of biochar from organic wastes promises to be an interesting source of plant nutrients, thus reducing pressure on natural resources. To assess the effect of biochar prepared from wastes filtration materials on the growth and production of common bean (Phaseolus vulgaris L.), three simultaneous greenhouse experiments were conducted with three different biochar from organic wastes (rice husk, sawdust, and sorghum silage) using as filtration material for swine biofertilizer. In each experiment the treatments consisted of the addition of five different biochar concentrations (0%, 2.5%, 5%, 7.5%, and 10% v/v), arranged in a completely random design, with four repetitions. Application of biochar increased the root dry mass, shoot dry mass, grain dry mass, number of pods and number of grains. These results indicated that biochar contributed significantly to the growth and production of common bean plants.

RESUMO: A produção de biochar a partir de resíduos orgânicos pode ser uma estratégia agronômica interessante como fonte de nutrientes para as plantas, diminuindo assim, a pressão sobre os recursos naturais. Com o objetivo de avaliar o efeito de biocarvões, produzidos de materiais filtrantes descartados, no crescimento e produção de feijão (Phaseolus vulgaris L.), conduziram-se simultaneamente três experimentos em casa de vegetação. Cada um dos experimentos foi representado pela aplicação de um biochar, os quais foram produzidos a partir de resíduos orgânicos de casca de arroz, serragem e restos de silagem de sorgo, utilizados como material filtrante para o biofertilizante suíno; e os tratamentos avaliados consistiram na adição de cinco níveis de biocarvão, isto é, 0, 2,5%, 5% 7,5% e 10% v/v. Nos três experimentos a aplicação de biochar aumentou a massa seca da raiz, massa seca da parte aérea, massa seca de grãos, número de vagens e número de grãos. Esses resultados indicam que os biochars contribuíram significativamente para o crescimento e produção do feijoeiro.

RESUMEN

Open-air burning of agricultural wastes from crops like corn, rice, sorghum, sugar cane, and wheat is common practice in Mexico, which in spite limiting regulations, is the method to eliminate such wastes, to clear the land for further harvesting, to control grasses, weeds, insects, and pests, and to facilitate nutrient absorption. However, this practice generates air pollution and contributes to the greenhouse effect. Burning of straws derived from the said crops was emulated in a controlled combustion chamber, hence determining emission factors for particles, black carbon, carbon dioxide, carbon monoxide, and nitric oxide throughout the process, which comprised three apparent stages: pre-ignition, flaming, and smoldering. In all cases, maximum particle concentrations were observed during the flaming stage, although the maximum final contributions to the particle emission factors corresponded to the smoldering stage. The comparison between particle size distributions (from laser spectrometer) and black carbon (from an aethalometer) confirmed that finest particles were emitted mainly during the flaming stage. Carbon dioxide emissions were also highest during the flaming stage whereas those of carbon monoxide were highest during the smoldering stage. Comparing the emission factors for each straw type with their chemical analyses (elemental, proximate, and biochemical), some correlations were found between lignin content and particle emissions and either particle emissions or duration of the pre-ignition stage. High ash or lignin containing-straw slowed down the pre-ignition and flaming stages, thus favoring CO oxidation to CO2.

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Hydrogen is a valuable clean energy source, and its production by biological processes is attractive and environmentally sound and friendly. In México 5 million tons/yr of agroindustrial wastes are generated; these residues are rich in fermentable organic matter that can be used for hydrogen production. On the other hand, batch, intermittently vented, solid substrate fermentation of organic waste has attracted interest in the last 10 years. Thus the objective of our work was to determine the effect of initial total solids content and initial pH on H2 production in batch fermentation of a substrate that consisted of a mixture of sugarcane bagasse, pineapple peelings, and waste activated sludge. The experiment was a response surface based on 2(2) factorial with central and axial points with initial TS (15-35%) and initial pH (6.5-7.5) as factors. Fermentation was carried out at 35 °C, with intermittent venting of minireactors and periodic flushing with inert N2 gas. Up to 5 cycles of H2 production were observed; the best treatment in our work showed cumulative H2 productions (ca. 3 mmol H2/gds) with 18% and 6.65 initial TS and pH, respectively. There was a significant effect of TS on production of hydrogen, the latter decreased with initial TS increase from 18% onwards. Cumulative H2 productions achieved in this work were higher than those reported for organic fraction of municipal solid waste (OFMSW) and mixtures of OFMSW and fruit peels waste from fruit juice industry, using the same process. Specific energetic potential due to H2 in our work was attractive and fell in the high side of the range of reported results in the open literature. Batch dark fermentation of agrowastes as practiced in our work could be useful for future biorefineries that generate biohydrogen as a first step and could influence the management of this type of agricultural wastes in México and other countries and regions as well.

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O objetivo deste trabalho foi avaliar o desenvolvimento in vitro de três linhagens de cogumelos [Pleurotus ostreatoroseus Singer, Pleurotus pulmonarius (Fr.) Quél. e Lentinus sajor caju (Fr.) Fr.], reativados em meio de cultura BDA e cultivadas em meios de cultura formulados à base de resíduos agrícolas, como a palha de arroz, casca de mamona, casca de amendoim. No meio sólido formulado foi adicionado um disco de cultura no centro da placa, estas foram incubadas a 25oC até a colonização do meio. Avaliou-se, diariamente, o diâmetro da colônia e obteve-se, aos cinco dias de cultivo, a massa miceliana, sendo os resultados obtidos submetidos a análise de variância e teste de Tukey. O meio contendo extrato da casca de amendoim foi o mais adequado para o crescimento da linhagem utilizada de Lentinus sajorcaju, que colonizou 68,30% da placa de Petri. O meio contendo extrato de casca de mamona foi mais favorável ao crescimento de Pleurotus ostreatoreoseus que colonizou 40,01% da placa. A linhagem nativa de Pleurotus pulmonarius cresceu indiferentemente nos meios testados e teve maior crescimento comparada a linhagem de Pleurotus ostreatoroseus. A linhagem de Lentinus sajor-caju no meio contendo extrato da casca de amendoim, apresentou massa micelial seca significativamente maior que todas as demais. O crescimento micelial das linhagens de Lentinus sajor-caju e Pleurotus ostreatoroseus é influenciado pelo meio de cultivo, enquanto o da linhagem nativa utilizada não é influenciado pelos meios testados.

The aim of this study was evaluate the in vitro development of three mushrooms strains [Pleurotus ostreatoroseus Singer, Pleurotus pulmonarius (Fr.) Quél. e Lentinus sajor-caju (Fr.) Fr.], growing media based in agricultural wastes, such rice straw, castor bean seed husks and peanut shells. In the solid medium was added a culture disc in the center of a petri dish and than was incubated at 25oC even the completly colonization of the medium, the data obtained were submitted to variance analysis and Tukey test. Was evaluated, daily, the colony diameter and the mycelial mass obtained after five days of culture. The medium containing peanut husks extract provides the optimal development for the Lentinus sajor-caju strain, when an average of 68.3% of each petri dishes was colonized by mycelia. The medium containig castor bean seed shells were most favorable for Pleurotus ostreatoreoseus development, such colonizing 40,01% of each petri dishes. The wild strain of Pleurotus pulmonarius grew indifferently in the tested media and reaches the higher development when compared with Pleurotus ostreatoroseus strain. Lentinus sajor-caju demonstrate significantly more mycelial dry mass in the peanut shells medium when compared with the others strains. This result suggests that the mycelial growing of Lentinus sajor-caju and Pleurotus ostreatoroseus are influencied by the media. For the wild strain the mycelial growing its not significantly influencied by the tested media.

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In this study, forty-two fungi from soil were isolated and tested for their carboxymethyl cellulase (CMCase) and xylanase activities. From all isolates, the fungal isolate FR60, which was identified as Aspergillus aculeatus Iizuka, showed high activities in both CMCase and xylanase with 517 mU/mg protein and 550 mU/mg protein, respectively. The crude enzyme from A. aculeatus Iizuka FR60 could hydrolyze several agricultural residues such as corncob, and sweet sorghum leaf and stalk at comparable rates with respect to the tested commercial enzymes and with a maximum rate in rice hull hydrolysis (29 μg sugar g-1 dry weight substrate mg-1 enzyme hr-1). The highest amount of glucose was obtained from corncob by using the crude enzyme from A. aculeatus Iizuka FR60 (10.1 g/100 g dry substrate). From overall enzymatic treatment results, the lowest sugar yield was from rice hulls treatment (1.6 g/100 g dry weight) and the highest amount of reducing sugar was obtained from rice straw treatment (15.3 g/100 g dry weight). Among tested agricultural wastes, rice hull could not be effectively hydrolyzed by enzymes, whereas sugarcane leaf and stalk, and peanut shell could be effectively hydrolyzed (30-31% total sugar comparing with total sugar yield from acid treatment).

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In this study, forty-two fungi from soil were isolated and tested for their carboxymethyl cellulase (CMCase) and xylanase activities. From all isolates, the fungal isolate FR60, which was identified as Aspergillus aculeatus Iizuka, showed high activities in both CMCase and xylanase with 517 mU/mg protein and 550 mU/mg protein, respectively. The crude enzyme from A. aculeatus Iizuka FR60 could hydrolyze several agricultural residues such as corncob, and sweet sorghum leaf and stalk at comparable rates with respect to the tested commercial enzymes and with a maximum rate in rice hull hydrolysis (29 µg sugar g(-1) dry weight substrate mg(-1) enzyme hr(-1)). The highest amount of glucose was obtained from corncob by using the crude enzyme from A. aculeatus Iizuka FR60 (10.1 g/100 g dry substrate). From overall enzymatic treatment results, the lowest sugar yield was from rice hulls treatment (1.6 g/100 g dry weight) and the highest amount of reducing sugar was obtained from rice straw treatment (15.3 g/100 g dry weight). Among tested agricultural wastes, rice hull could not be effectively hydrolyzed by enzymes, whereas sugarcane leaf and stalk, and peanut shell could be effectively hydrolyzed (30-31% total sugar comparing with total sugar yield from acid treatment).

RESUMEN

In this study, forty-two fungi from soil were isolated and tested for their carboxymethyl cellulase (CMCase) and xylanase activities. From all isolates, the fungal isolate FR60, which was identified as Aspergillus aculeatus Iizuka, showed high activities in both CMCase and xylanase with 517 mU/mg protein and 550 mU/mg protein, respectively. The crude enzyme from A. aculeatus Iizuka FR60 could hydrolyze several agricultural residues such as corncob, and sweet sorghum leaf and stalk at comparable rates with respect to the tested commercial enzymes and with a maximum rate in rice hull hydrolysis (29 g sugar g-1 dry weight substrate mg-1 enzyme hr-1). The highest amount of glucose was obtained from corncob by using the crude enzyme from A. aculeatus Iizuka FR60 (10.1 g/100 g dry substrate). From overall enzymatic treatment results, the lowest sugar yield was from rice hulls treatment (1.6 g/100 g dry weight) and the highest amount of reducing sugar was obtained from rice straw treatment (15.3 g/100 g dry weight). Among tested agricultural wastes, rice hull could not be effectively hydrolyzed by enzymes, whereas sugarcane leaf and stalk, and peanut shell could be effectively hydrolyzed (30-31% total sugar comparing with total sugar yield from acid treatment).

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ABSTRACT The effect of sawdust supplementation of coconut bark with 0, 20 and 40% of wheat and/or rice bran on growth rate (cm day -1), vigor, period of primordials formation and yield of two strains of Pleurotus ostreatus and one of P. ostreatoroseus were investigated. The supplementation influenced all parameters tested.

RESUMO O efeito da suplementação do substrato à base de serragem da casca de coco com 0, 20 e 40% de farelo de trigo e/ou de arroz, em condições axênicas, foi avaliado sobre a velocidade de crescimento (cm dia-1), o vigor, o período de formação de primórdios e na produtividade de dois isolados de Pleurotus ostreatus e um isolado de P. ostreatoroseus. A suplementação favoreceu todos os parâmetros analisados.

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The preliminary results obtained in the study on the production of enzymatic hydrolysate from pineapple plant stem and its fermentation to ethanol by the yeast Saccharomyces cerevisiae are presented. The dried and milled (40 mesh screen) plant stem was pretreated at 100C for 10 min. in 1% aqueous solution before its saccharification with amiloglucosidase (50 IU/mg). Starch sacchariflcation yield was 71.77%. The alcoholic fermentation was performed on the hydrolysate (reducing sugar content: 3.3% d.w.) with the addition of 1% yeast extract, 1% ammonium sulphate. The yeast Saccharomyces cerevisiae was able to transform the substrate to ethanol at 30 pH 3.5 and 50 cpm of agitation. For each gram of reduced sugar, 0.431g of ethanol and 0.0447 g of biomass were produced. The alcoholic yield was 84.46% of the theoretical value. In view of these results, it is concluded that the pineapple plant stem could yield 282 Liters of ethanol/ton.

A informação apresentada neste trabalho mostra resultados preliminares da pesquisa na produção de hidrolisados enzimáticos do caule de abacaxizeiro e sua subseqüente fermentação a etanol pela levedura Saccharomyces cerevisiae. O caule do abacaxizeiro seco e moído (tamanho partícula entre 0.84 e 0.42 mm) foi submetido a um pré-tratamento térmico a 100C durante diferentes tempos antes da sua sacarificação com a enzima amiloglucosidase (50 UI/mg). Quando o caule do abacaxizeiro foi submetido a 100C durante 10 minutos, forneceu um substrato mais susceptível à hidrolise enzimática em relação ao fornecido pelo caule sem pré-tratamento. Tempos maiores de pré-tratamento a 100C não melhoraram a susceptibilidade do substrato à enzima. A sacarificação do amido presente inicialmente no caule foi de 71,77%. A levedura Saccharomyces cerevisiae foi capaz de transformar os hidrolisados do caule do abacaxizeiro obtidos de acordo ao indicado acima, a etanol, sob as condições de fermentação de 30C, pH 3,5 e 50 cpm de agitação. A fermentação alcoólica foi realizada em meio contendo 1% de extrato de levedura, 1% de sulfato de amônio e 3,3% de açúcares redutores de hidrolisado enzimático do caule do abacaxizeiro. Foram produzidos 0,431 g de etanol e 0,044/ g de biomassa por grama de açúcar redutor consumido. O rendimento alcóolico foi 84,46% do valor teórico. Na base destes resultados o caule

RESUMEN

The preliminary results obtained in the study on the production of enzymatic hydrolysate from pineapple plant stem and its fermentation to ethanol by the yeast Saccharomyces cerevisiae are presented. The dried and milled (40 mesh screen) plant stem was pretreated at 100C for 10 min. in 1% aqueous solution before its saccharification with amiloglucosidase (50 IU/mg). Starch sacchariflcation yield was 71.77%. The alcoholic fermentation was performed on the hydrolysate (reducing sugar content: 3.3% d.w.) with the addition of 1% yeast extract, 1% ammonium sulphate. The yeast Saccharomyces cerevisiae was able to transform the substrate to ethanol at 30 pH 3.5 and 50 cpm of agitation. For each gram of reduced sugar, 0.431g of ethanol and 0.0447 g of biomass were produced. The alcoholic yield was 84.46% of the theoretical value. In view of these results, it is concluded that the pineapple plant stem could yield 282 Liters of ethanol/ton.  

A informação apresentada neste trabalho mostra resultados preliminares da pesquisa na produção de hidrolisados enzimáticos do caule de abacaxizeiro e sua subseqüente fermentação a etanol pela levedura Saccharomyces cerevisiae. O caule do abacaxizeiro seco e moído (tamanho partícula entre 0.84 e 0.42 mm) foi submetido a um pré-tratamento térmico a 100C durante diferentes tempos antes da sua sacarificação com a enzima amiloglucosidase (50 UI/mg). Quando o caule do abacaxizeiro foi submetido a 100C durante 10 minutos, forneceu um substrato mais susceptível à hidrolise enzimática em relação ao fornecido pelo caule sem pré-tratamento. Tempos maiores de pré-tratamento a 100C não melhoraram a susceptibilidade do substrato à enzima. A sacarificação do amido presente inicialmente no caule foi de 71,77%. A levedura Saccharomyces cerevisiae foi capaz de transformar os hidrolisados do caule do abacaxizeiro obtidos de acordo ao indicado acima, a etanol, sob as condições de fermentação de 30C, pH 3,5 e 50 cpm de agitação. A fermentação alcoólica foi realizada em meio contendo 1% de extrato de levedura, 1% de sulfato de amônio e 3,3% de açúcares redutores de hidrolisado enzimático do caule do abacaxizeiro. Foram produzidos 0,431 g de etanol e 0,044/ g de biomassa por grama de açúcar redutor consumido. O rendimento alcóolico foi 84,46% do valor teórico. Na base destes resultados o caule