Biomass of unconventional plants from Brazilian semiarid as substrate for hydrolytic enzymes production by Aspergillus niger under solid and submerged fermentation

Aspergillus niger KIJH was grown in solid and submerged fermentation using leaves and roots (with and without bark) of plants typically from Brazilian semiarid as substrate to produce a multienzymatic extract, which was characterised for its potential biotechnological applications. Solid-state fermentation (SSF) was applied to select the most promising plants biomass as induction substrates for the production of hydrolytic enzymes by fungus. The best biomasses were used as substrate in submerged fermentation (SmF) assays at two scales. Samples of up scale fermented culture were partially purified by ultrafiltration and activity and pH and temperature stability of CMCase and xylanase were evaluated. A. niger KIJH produced hydrolytic enzymes under SSF containing unconventional plants biomass from Brazilian semiarid. In SmF conditions, maximum CMCase (0.264 U mL-1) and xylanase (1.163 U mL-1) activities were induced by Jacaratia corumbensis. Scaling up the SmF to 500 mL of medium was able to maintain constant the production of CMCase (0.346 U mL-1) and xylanase (1.273 U mL-1) on the fermented culture. Ultrafiltered and concentrated extract presented CMCase activities practically constant in all temperature ranges (30-80°C) and pH (3.0-9.0), while xylanase optimum activity temperature was 50°C and pH in the range of 3.0 to 5.0. CMCase activity remained stable for 24 hours at 50°C

Biomass of unconventional plants from Brazilian semiarid as substrate for hydrolytic enzymes production by Aspergillus niger under solid and submerged fermentation

Aspergillus niger KIJH was grown in solid and submerged fermentation using leaves and roots (with and without bark) of plants typically from Brazilian semiarid as substrate to produce a multienzymatic extract, which was characterised for its potential biotechnological applications. Solid-state fermentation (SSF) was applied to select the most promising plants biomass as induction substrates for the production of hydrolytic enzymes by fungus. The best biomasses were used as substrate in submerged fermentation (SmF) assays at two scales. Samples of up scale fermented culture were partially purified by ultrafiltration and activity and pH and temperature stability of CMCase and xylanase were evaluated. A. niger KIJH produced hydrolytic enzymes under SSF containing unconventional plants biomass from Brazilian semiarid. In SmF conditions, maximum CMCase (0.264 U mL-1) and xylanase (1.163 U mL-1) activities were induced by Jacaratia corumbensis. Scaling up the SmF to 500 mL of medium was able to maintain constant the production of CMCase (0.346 U mL-1) and xylanase (1.273 U mL-1) on the fermented culture. Ultrafiltered and concentrated extract presented CMCase activities practically constant in all temperature ranges (30-80°C) and pH (3.0-9.0), while xylanase optimum activity temperature was 50°C and pH in the range of 3.0 to 5.0. CMCase activity remained stable for 24 hours at 50°C(AU)

Phytochemical profile and antifungal action of Anadenanthera colubrina extract on the quality of maize seeds

Maize (Zea mays L.) is among the most cultivated crops in the world and can be affected by several diseases, especially those transmitted by seeds. The study of alternatives to fungicides used for seed treatment has a promising field in essential oils. Thus, this study determined the phytochemical profile of the ethanolic extract from Anadenanthera colubrina (Vell.) Brenan and to evaluate its antifungal activity on the sanitary and physiological quality of maize seeds. The seeds used were of the Jaboatão cultivar, which were submitted to the following treatments: control (untreated seeds), commercial fungicide (dicarboximide) and A. colubrina extract at 200, 400, 600, 800, and 1,000 ppm. The seeds were subjected to sanitary and germination tests in a completely randomized experimental design. Phytochemical prospecting of A. colubrina extract indicated the presence of alkaloids, tannins, flavonoids and saponins, as well as the major compounds lupeol, gallic acid, ferulic acid, catechin and quercetin. The A. colubrina extract reduced the incidence of Aspergillus spp., including Aspergillus niger, Alternaria spp., Curvularia spp. and Fusarium spp. at all concentrations. The highest concentrations (800 and 1,000 ppm) of the A. colubrina extract reduced the incidence of Penicillium spp. and yielded an effective control of Rhizoctonia spp. The extract of A. colubrina did not present phytotoxic effect, guaranteeing the viability and vigor of maize seeds.

Biosorption potential of lead tolerant fungi isolated from refuse dumpsite soil in Nigeria

Metals are non-biodegradable and recurrent in the environs. Heavy metals tolerant fungiwere isolated from refuse dumpsite soil using pour plate method. These fungiwere identified as Aspergillus niger, Penicillium chrysogenumandRhizomucor sp. The fungal isolates were screened for cadmium (Cd), lead (Pb) and zinc (Zn) with concentration of 200ppm, 400ppm and 600ppm. Aspergillus nigerand Penicillium chrysogenumshowed high tolerance for the metals in contrast to the control. The fungiwith high tolerance were used for biosorption study. However, Penicillium chrysogenumshowed higher lead removal or biosorption potential of 1.07ppm, 3.35ppm and 4.19ppm as compared with Aspergillus nigerwith lead removal of 0.67ppm, 3.11ppm and 3.79ppm at 5th, 10thand 15thday respectively. One-way Analysis of Variance was used to interpret the data generated from the biosorption study which revealed that there was no significant different (p>0.05)between the lead removal of Aspergillus nigerandPenicillium chrysogenumon the 5thday but there was significant difference (p<0.05)in the lead removal of Aspergillus nigerand Penicillium chrysogenumon the 10thand 15thday. This study suggests the use of these fungal isolates for removal and biotreatment of heavy metal contaminated and polluted environment.

Optimizing culture conditions for production of intra and extracellular inulinase and invertase from Aspergillus niger ATCC 20611 by response surface methodology (RSM)

The aim of this study was obtain a model that maximizes growth and production of inulinase and invertase by Aspergillus niger ATCC 20611, employing response surface methodology (RSM). The RSM with a five-variable and three-level central composite design (CCD) was employed to optimize the medium composition. Results showed that the experimental data could be appropriately fitted into a second-order polynomial model with a coefficient of determination (R2) more than 0.90 for all responses. This model adequately explained the data variation and represented the actual relationships between the parameters and responses. The pH and temperature value of the cultivation medium were the most significant variables and the effects of inoculum size and agitation speed were slightly lower. The intra-extracellular inulinase, invertase production and biomass content increased 10-32 fold in the optimized medium condition (pH 6.5, temperature 30 °C, 6% (v/v), inoculum size and 150 rpm agitation speed) by RSM compared with medium optimized through the one-factor-at-a-time method. The process development and intensification for simultaneous production of intra-extracellular inulinase (exo and endo inulinase) and invertase from A. niger could be used for industrial applications.(AU)

Reuse of wastewater from pulp industry for the optimization of fungal xylanase production / Reutilização de efluentes da indústria de celulose para otimização da produção de xilanase fúngica

The production of enzymes using agro-industrial waste is a low cost alternative for the reuse of byproducts, with the subsequent impact decrease on the environment. Current analysis produced xylanase using fungus Aspergillus niger, with two types of wastewater generated during the pulp chemical bleaching phase as inducers. Xylanase was produced by submerged liquid fermentation and factorial design optimized parameters that influence production (concentration of wastewater and production period). Initial culture conditions (pH, temperature and agitation) were optimized independently. Alkaline wastewater was more effective than acidic wastewater for the induction of xylanase in optimized conditions: 50% of culture medium, 7-day production, 30C, pH 6.0 and agitation at 160 rpm. Despite different results, acidic and alkaline wastewaters induced xylanase production by A. niger when employed in concentrations lower than or equal to 50% of culture medium and in the most optimal conditions described above. Alkaline wastewater is highlighted as the most efficient for such production. 

A produção de enzimas, a partir de resíduos agroindustriais, é uma alternativa para reutilização destes subprodutos como substrato de baixo custo reduzindo seu impacto causado pelo descarte no meio ambiente. Diante disso, o objetivo deste estudo foi a produção de xilanase por Aspergillus niger, utilizando dois efluentes gerados nas fases de branqueamento químico de polpa de celulose como indutores. A produção de xilanase foi realizada por fermentação líquida submersa, e utilizou-se planejamento fatorial para otimização dos parâmetros influentes de produção (concentração de efluentes e período de produção) e as condições iniciais de cultivo (pH, temperatura e agitação) foram otimizadas de forma independente. O efluente alcalino se mostrou mais efetivo do que o efluente com característica ácida, na indução de xilanase em condições otimizadas: 50% em relação ao meio de cultura, sete dias de produção, 30°C, pH 6,0 e agitação de 160 rpm. Conclui-se que ambos os efluentes, ácido e alcalino, apesar de levarem a diferentes resultados, são capazes de induzir a produção de xilanase por A. niger quando empregues em concentrações menores ou iguais a 50% em relação ao meio de cultura e nas condições ótimas descritas acima, destacando-se o efluente alcalino como mais eficiente para produção de tal enzima.(AU)

Surface response methodology for the optimization of lipase production under submerged fermentation by filamentous fungi

A PlackettBurman Factorial Design of 16 experiments was conducted to assess the influence of nine factors on the production of lipases by filamentous fungi. The factors investigated were bran type (used as the main carbon source), nitrogen source, nitrogen source concentration, inducer, inducer concentration, fungal strain (Aspergillus niger or Aspergillus flavus were selected as good lipase producers via submerged fermentation), pH and agitation. The concentration of the yeast extract and soybean oil and the pH had a significant effect (p 0.05) on lipase production and were consecutively studied through a Full Factorial Design 23, with the concentration of yeast extract and pH being significant (p 0.05). These variables were optimized using a central composite design, obtaining maximum lipolytic activities with the use of 45 g/L of yeast extract and pH 7.15. The statistical model showed a 94.12% correlation with the experimental data.(AU)

Aproveitamento de resíduos da agroindústria do óleo de dendê para a produção de lipase por Aspergillus Níger / Agro-industrial residues utilization of palm oil for lipase production by Aspergillus niger

Neste trabalho, foi avaliado o desempenho de duas linhagens de Aspergillus niger (mutante 11T53A14 e selvagem C) previamente selecionadas como promissoras para a produção de lipases, utilizando meios de cultivo formulados a partir da torta de dendê (palmiste) e da borra alcalina do refino do óleo de dendê (borra de dendê), resíduos provenientes da agroindústria do óleo de dendê (palma) por fermentação em estado sólido (FES). Os experimentos de produção da enzima em FES foram conduzidos em colunas aeradas, incubadas em banho-maria a 32ºC com entrada controlada de ar não umedecido de 1,0vvm. Os melhores resultados foram obtidos com a cepa mutante A. niger 11T53A14 em meio contendo torta de dendê umedecida com solução sulfato de amônio (1,2%) e com a adição de 3% da borra de dendê. O valor máximo da atividade da lipase neste meio foi de 72,57U gss-1 em 48 horas. Esse valor foi 47,5% superior ao obtido no meio sem a borra de dendê. A comparação do desempenho da cepa mutante com a cepa selvagem mostrou que o meio composto por torta de dendê adicionado com sulfato de amônio e borra de dendê induziu ambas as linhagens a produzir lipases com bons níveis de atividade, além de reduzir o tempo de processo de fermentação.(AU)

In this paper it was evaluated the performance of two strains of Aspergillus niger (mutant 11T53A14 and wild type C) previously selected as promising for lipase production, from cultivation media formulated from palm kernel cake (kernel) and alkaline sludge from refining were evaluated palm oil (palm oil sludge), palm oil (palm) waste industrialization by solid state fermentation (SSF). Experiments of enzyme production in SSF were conducted in aerated columns, incubated in a water bath at 32°C with controlled inlet of 1.0vvm. The best results were obtained with the mutant strain A. niger 11T53A14 in medium containing palm kernel cake moistened with a solution of ammonium sulfate (1.2%) and with the addition of 3% of palm oil sludge. The maximum lipase activity in this medium was 72.57U gdw-1 in 48 hours and 47.5% higher than in the medium without sludge palm. A comparison of the performance of the mutant strain with the wild-type strain showed that the medium composed of palm kernel cake added with ammonium sulfate and blurs palm induced both strains to produce lipases with good activity levels and reduced the time of the fermentation process.(AU)

Bioleaching of gold, copper and nickel from waste cellular phone PCBs and computer goldfinger motherboards by two Aspergillus nigerstrains

In an effort to develop alternate techniques to recover metals from waste electrical and electronic equipment (WEEE), this research evaluated the bioleaching efficiency of gold (Au), copper (Cu) and nickel (Ni) by two strains of Aspergillus niger in the presence of gold-plated finger integrated circuits found in computer motherboards (GFICMs) and cellular phone printed circuit boards (PCBs). These three metals were analyzed for their commercial value and their diverse applications in the industry. Au-bioleaching ranged from 42 to 1% for Aspergillus niger strain MXPE6; with the combination of Aspergillus niger MXPE6 + Aspergillus niger MX7, the Au-bioleaching was 87 and 28% for PCBs and GFICMs, respectively. In contrast, the bioleaching of Cu by Aspergillus niger MXPE6 was 24 and 5%; using the combination of both strains, the values were 0.2 and 29% for PCBs and GFICMs, respectively. Fungal Ni-leaching was only found for PCBs, but with no significant differences among treatments. Improvement of the metal recovery efficiency by means of fungal metabolism is also discussed..(AU)

Enhancing inulinase yield by irradiation mutation associated with optimization of culture conditions

A new inulinase-producing strain was isolated from rhizosphere soils of Jerusalem artichoke collected from Shihezi (Xinjiang, China) using Jerusalem artichoke power (JAP) as sole carbon source. It was identified as an Aspergillus niger strain by analysis of 16S rRNA. To improve inulinase production, this fungus was subjected to mutagenesis induced by ⁶⁰Co γ-irradiation. A genetically stable mutant (designated E12) was obtained and it showed 2.7-fold higher inulinase activity (128 U/mL) than the parental strain in the supernatant of a submerged culture. Sequential methodology was used to optimize the inulinase production of stain E12. A screening trial was first performed using Plackett-Burman design and variables with statistically significant effects on inulinase bio-production were identified. These significant factors were further optimized by central composite design experiments and response surface methodology. Finally, it was found that the maximum inulinase production (185 U/mL) could be achieved under the optimized conditions namely pH 7.0, yeast extract concentration of 5.0 g/L, JAP concentration of 66.5 g/L, peptone concentration of 29.1 g/L, solution volume of 49.4 mL in 250-mL shake flasks, agitation speed of 180 rpm, and fermentation time of 60 h. The yield of inulinase under optimized culture conditions was approximately 1.4-fold of that obtained by using basal culture medium. These findings are of significance for the potential industrial application of the mutant E12.(AU)

Chemical modification of Aspergillus niger B-glucosidase and its catalytic properties

Aspergillus niger β-glucosidase was modified by covalent coupling to periodate activated polysaccharides (glycosylation). The conjugated enzyme to activated starch showed the highest specific activity (128.5 U/mg protein). Compared to the native enzyme, the conjugated form exhibited: a higher optimal reaction temperature, a lower Ea (activation energy), a higher Km (Michaelis constant) and Vmax (maximal reaction rate), and improved thermal stability. The calculated t1/2 (half-life) values of heat in-activation at 60 °C and 70 °C were 245.7 and 54.5 min respectively, whereas at these temperatures the native enzyme was less stable (t1/2 of 200.0 and 49.5 min respectively). The conjugated enzyme retained 32.3 and 29.7%, respectively from its initial activity in presence of 5 mM Sodium Dodecyl Sulphate (SDS) and p-Chloro Mercuri Benzoate (p-CMB), while the native enzyme showed a remarkable loss of activity (retained activity 1.61 and 13.7%, respectively). The present work has established the potential of glycosylation to enhance the catalytic properties of β-glucosidase enzyme, making this enzyme potentially feasible for biotechnological applications.(AU)

Hydroxylation of 1, 8-cineole by Mucor ramannianus and Aspergillus niger

The monoterpenoid 1,8-cineole is obtained from the leaves of Eucalyptus globulus and it has important biological activities. It is a cheap natural substrate because it is a by-product of the Eucalyptus cultivation for wood and pulp production. In this study, it was evaluated the potential of three filamentous fungi in the biotransformation of 1,8-cineole. The study was divided in two steps: first, reactions were carried out with 1,8-cineole at 1 g/L for 24 h; afterwards, reactions were carried out with substrate at 5 g/L for 5 days. The substrate was hydroxylated into 2-exo-hydroxy-1,8-cineole and 3-exo-hydroxy-1,8-cineole by fungi Mucor ramannianus and Aspergillus niger with high stereoselectivity. Trichoderma harzianum was also tested but no transformation was detected. M. ramannianus led to higher than 99% of conversion within 24 h with a starting high substrate concentration (1 g/L). When substrate was added at 5 g/L, only M. ramannianus was able to catalyze the reaction, but the conversion level was 21.7% after 5 days. Both products have defined stereochemistry and could be used as chiral synthons. Furthermore, biological activity has been described for 3-exo-hydroxy-1,8-cineol. To the best of our knowledge, this is the first report on the use of M. ramannianus in this reaction.(AU)

Thermotolerant and mesophylic fungi from sugarcane bagasse and their prospection for biomass-degrading enzyme production

Nineteen fungi and seven yeast strains were isolated from sugarcane bagasse piles from an alcohol plant located at Brazilian Cerrado and identified up to species level on the basis of the gene sequencing of 5.8S-ITS and 26S ribosomal DNA regions. Four species were identified: Kluyveromyces marxianus, Aspergillus niger, Aspergillus sydowii and Aspergillus fumigatus, and the isolates were screened for the production of key enzymes in the saccharification of lignocellulosic material. Among them, three strains were selected as good producers of hemicellulolitic enzymes: A. niger (SBCM3), A. sydowii (SBCM7) and A. fumigatus (SBC4). The best β-xylosidase producer was A. niger SBCM3 strain. This crude enzyme presented optimal activity at pH 3.5 and 55 °C (141 U/g). For β-glucosidase and xylanase the best producer was A. fumigatus SBC4 strain, whose enzymes presented maximum activity at 60 °C and pH 3.5 (54 U/g) and 4.0 (573 U/g), respectively. All these crude enzymes presented stability around pH 3.0–8.0 and up to 60 °C, which can be very useful in industrial processes that work at high temperatures and low pHs. These enzymes also exhibited moderate tolerance to ethanol and the sugars glucose and xylose. These similar characteristics among these fungal crude enzymes suggest that they can be used synergistically in cocktails in future studies of biomass conversion with potential application in several biotechnological sectors..(AU)

Screening of thermotolerant and thermophilic fungi aiming Beta-xylosidase and arabinanase production

Plant cell wall is mainly composed by cellulose, hemicellulose and lignin. The heterogeneous structure and composition of the hemicellulose are key impediments to its depolymerization and subsequent use in fermentation processes. Thus, this study aimed to perform a screening of thermophilic and thermotolerant filamentous fungi collected from different regions of the São Paulo state, and analyze the production of β-xylosidase and arabinanase at different temperatures. These enzymes are important to cell wall degradation and synthesis of end products as xylose and arabinose, respectively, which are significant sugars to fermentation and ethanol production. A total of 12 fungal species were analyzed and 9 of them grew at 45 ºC, suggesting a thermophilic or thermotolerant character. Additionally Aspergillus thermomutatus anamorph of Neosartorya and A. parasiticus grew at 50 ºC. Aspergillus niger and Aspergillus thermomutatus were the filamentous fungi with the most expressive production of β-xylosidase and arabinanase, respectively. In general for most of the tested microorganisms, β-xylosidase and arabinanase activities from mycelial extract (intracellular form) were higher in cultures grown at high temperatures (35-40 ºC), while the correspondent extracellular activities were favorably secreted from cultures at 30 ºC. This study contributes to catalogue isolated fungi of the state of São Paulo, and these findings could be promising sources for thermophilic and thermotolerant microorganisms, which are industrially important due to their enzymes.

Utilization of molasses and sugar cane bagasse for production of fungal invertase in solid state fermentation using Aspergillus niger GH1

Agro-industrial wastes have been used as substrate-support in solid state fermentation for enzyme production. Molasses and sugarcane bagasse are by-products of sugar industry and can be employed as substrates for invertase production. Invertase is an important enzyme for sweeteners development. In this study, a xerophilic fungus Aspergillus niger GH1 isolated of the Mexican semi-desert, previously reported as an invertase over-producer strain was used. Molasses from Mexico and Cuba were chemically analyzed (total and reducer sugars, nitrogen and phosphorous contents); the last one was selected based on chemical composition. Fermentations were performed using virgin and hydrolyzate bagasse (treatment with concentrated sulfuric acid). Results indicated that, the enzymatic yield (5231 U/L) is higher than those reported by other A. niger strains under solid state fermentation, using hydrolyzate bagasse. The acid hydrolysis promotes availability of fermentable sugars. In addition, maximum invertase activity was detected at 24 h using low substrate concentration, which may reduce production costs. This study presents an alternative method for invertase production using a xerophilic fungus isolated from Mexican semi-desert and inexpensive substrates (molasses and sugarcane bagasse).

Bioremediation of dyes by fungi isolated from contaminated dye effluent sites for bio-usability

Biodegradation and detoxification of dyes, Malachite green, Nigrosin and Basic fuchsin have been carried out using two fungal isolates Aspergillus niger, and Phanerochaete chrysosporium, isolated from dye effluent soil. Three methods were selected for biodegradation, viz. agar overlay and liquid media methods; stationary and shaking conditions at 25 °C. Aspergillus niger recorded maximum decolorization of the dye Basic fuchsin (81.85%) followed by Nigrosin (77.47%), Malachite green (72.77%) and dye mixture (33.08%) under shaking condition. Whereas, P. chrysosporium recorded decolorization to the maximum with the Nigrosin (90.15%) followed by Basic fuchsin (89.8%), Malachite green (83.25%) and mixture (78.4%). The selected fungal strains performed better under shaking conditions compared to stationary method; moreover the inoculation of fungus also brought the pH of the dye solutions to neutral from acidic. Seed germination bioassay study exhibited that when inoculated dye solutions were used, seed showed germination while uninoculated dyes inhibited germination even after four days of observation. Similarly, microbial growth was also inhibited by uninoculated dyes. The excellent performance of A. niger and P. chrysporium in the biodegradation of textile dyes of different chemical structures suggests and reinforces the potential of these fungi for environmental decontamination.

Production of xylanases by an Aspergillus niger strain in wastes grain / Produção de xilanases por uma linhagem de Aspergillus niger em resíduos de grãos

Many fungi are used in order to extract products from their metabolism through bioprocesses capable of minimizing adverse effects caused by agro-industrial wastes in the environment. The aim of this study was to evaluate the xylanase production by an Aspergillus niger strain, using agro-industrial wastes as substrate. Brewers spent grain was the best inducer of xylanase activity. Higher levels of xylanase were obtained when the fungus was grown in liquid Vogel medium, pH 5.0, at 30؛C, during 5 days. The temperature for optimum activity was 50؛C and optimum pH 5.0. The enzyme was stable at 50؛C, with a half-life of 240 min. High pH stability was verified from pH 4.5 to 7.0. These characteristics exhibited by A. niger xylanase turn this enzyme attractive for some industrial applications, such as in feed and food industries. Additionally, the use of brewers spent grain, an abundantly available and low-cost residue, as substrate for xylanase production can not only add value and decrease the amount of this waste, but also reduce xylanase production cost.(AU)

Muitos fungos sمo utilizados com a finalidade de extrair produtos de seu metabolismo, por meio de bioprocessos capazes de minimizar efeitos nocivos que resيduos agroindustriais causam ao meio ambiente. O objetivo deste estudo foi avaliar a produçمo de xilanases por uma linhagem de Aspergillus niger, empregando resيduos agroindustriais como substrato. O bagaço de malte foi o melhor resيduo indutor da atividade xilanلsica. Maiores nيveis de xilanases foram obtidos quando o fungo foi cultivado em meio lيquido de Vogel, pH 5,0, a 30؛C, durante cinco dias. A temperatura َtima estabelecida para a atividade xilanلsica foi a de 50؛C e o pH َtimo 5,0. A enzima foi estلvel a 50؛C, apresentando uma meia vida de 240 min. Elevada estabilidade enzimلtica foi verificada entre os pH 4,5 e 7,0. As caracterيsticas bioquيmicas exibidas pela xilanase produzida por A. niger tornam esta enzima atraente para determinadas aplicaçُes industriais, como as indْstrias de raçمo animal e alimentيcia. Adicionalmente, a utilizaçمo do bagaço de malte, um resيduo disponيvel em abundância e de baixo custo como substrato para a produçمo de xilanases poderل nمo somente adicionar valor a este resيduo, como também reduzir os custos de produçمo destas enzimas.(AU)

Some factors affecting tannase production by Aspergillus niger Van Tieghem

One variable at a time procedure was used to evaluate the effect of qualitative variables on the production of tannase from Aspergillus niger Van Tieghem. These variables including: fermentation technique, agitation condition, tannins source, adding carbohydrates incorporation with tannic acid, nitrogen source type and divalent cations. Submerged fermentation under intermittent shaking gave the highest total tannase activity. Maximum extracellular tannase activity (305 units/ 50 mL) was attained in medium containing tannic acid as tannins source and sodium nitrate as nitrogen source at 30 ºC for 96 h. All added carbohydrates showed significant adverse effects on the production of tannase. All tested divalent cations significantly decreased tannase production. Moreover, split plot design was carried out to study the effect of fermentation temperature and fermentation time on tannase production. The results indicated maximum tannase production (312.7 units/50 mL) at 35 ºC for 96 h. In other words, increasing fermentation temperature from 30 ºC to 35 ºC resulted in increasing tannase production.(AU)

Aspergellus niger como produtor de enzimas celuloliticas a partir farelo de cacau (theobroma cacao) / Aspergellus niger as a producer of cellulolytic enzymes from cocoa (Theobroma cacao) meal

O objetivo deste trabalho foi estudar a aplicação do fungo Aspergillus niger como produtor das enzimas celulolíticas CMCase, FPase e Xilanase, através da fermentação em estado sólido de cacau (Theobroma cacao). Avaliaram-se o efeito do tempo de fermentação (24, 72, e 120 horas) e da atividade de água (0,963; 0,976 e 0,983) sobre a produção das enzimas. As fermentações foram realizadas a 30º C em estufa bacteriológica. A otimização das condições ideais para produção de enzimas foi realizada a partir da Metodologia de Superfície de Resposta (MSR). Estatisticamente, as melhores atividades para a CMCase obtidas foram 14,18 U/mL em 0,972 aw e 70,07 horas de fermentação, para a FPase 7,51 U/mL 0,974 aw 80,56 horas e para a Xilanase foi 11,86 U/mL 0,971 aw e 64,24 horas.

Aspergellus niger as a producer of cellulolytic enzymes from cocoa (Theobroma cacao) meal. The aim of this work was to study the application of the fungus Aspergillus niger as a producer of the cellulolytic enzymes CMCase, FPase and Xylanase by solid-state fermentation of cocoa (Theobroma cacao). We evaluated the effect of fermentation time (24, 72, and 120 hours) and water activity (0.963, 0.976 and 0.983) on the production of enzymes. Fermentations were performed at 30º C in a bacteriological incubator. The optimization of ideal conditions for enzyme production was carried out using the response surface methodology (RSM). Statistically, the best activity obtained for CMCase was 14.18 U/mL at aw 0.972 and 70.07 hours fermentation, for FPase it was 7.51 U/mL at 0.974 aw and 80.56 hours, while for Xylanase was 11.86 U/mL at aw 0.971 and 64.24 hours.

Aspergellus niger como produtor de enzimas celuloliticas a partir farelo de cacau (theobroma cacao) / Aspergellus niger as a producer of cellulolytic enzymes from cocoa (Theobroma cacao) meal

O objetivo deste trabalho foi estudar a aplicação do fungo Aspergillus niger como produtor das enzimas celulolíticas CMCase, FPase e Xilanase, através da fermentação em estado sólido de cacau (Theobroma cacao). Avaliaram-se o efeito do tempo de fermentação (24, 72, e 120 horas) e da atividade de água (0,963; 0,976 e 0,983) sobre a produção das enzimas. As fermentações foram realizadas a 30º C em estufa bacteriológica. A otimização das condições ideais para produção de enzimas foi realizada a partir da Metodologia de Superfície de Resposta (MSR). Estatisticamente, as melhores atividades para a CMCase obtidas foram 14,18 U/mL em 0,972 aw e 70,07 horas de fermentação, para a FPase 7,51 U/mL 0,974 aw 80,56 horas e para a Xilanase foi 11,86 U/mL 0,971 aw e 64,24 horas. (AU)

Aspergellus niger as a producer of cellulolytic enzymes from cocoa (Theobroma cacao) meal. The aim of this work was to study the application of the fungus Aspergillus niger as a producer of the cellulolytic enzymes CMCase, FPase and Xylanase by solid-state fermentation of cocoa (Theobroma cacao). We evaluated the effect of fermentation time (24, 72, and 120 hours) and water activity (0.963, 0.976 and 0.983) on the production of enzymes. Fermentations were performed at 30º C in a bacteriological incubator. The optimization of ideal conditions for enzyme production was carried out using the response surface methodology (RSM). Statistically, the best activity obtained for CMCase was 14.18 U/mL at aw 0.972 and 70.07 hours fermentation, for FPase it was 7.51 U/mL at 0.974 aw and 80.56 hours, while for Xylanase was 11.86 U/mL at aw 0.971 and 64.24 hours. (AU)