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The Application of a combination of enzymes is the best alternative to reduce the use of chemicals in the paper industry. Bacillus sp. NG-27 and Bacillus nealsonii PN-11 are known to produce thermoalkali stable xylanse (X) and mannanase (M) respectively having potential for pulp biobleaching. The Present study, reports the production of a mixture of X + M by co-culturing of strains in SSF and standardizing its application for pulp biobleaching. Production of enzymes by co-cultivation in SSF was optimized by statistical methods. Substantial increase in the yield of enzymes; 3.61 fold of xylanase and 37.71 fold of mannanase was achieved. Application of enzyme cocktail for pulp biobleaching resulted in a 45.64% reduction of kappa number with 55 IU g−1odp of enzyme dose (xylanase:mannanase; 3:1) at pH 8.0 in 1h at 65 °C along with significant increase in brightness (11%) and whiteness (75%). The Same quality of paper as made up from chemical treated pulp can be made from enzyme-treated pulp with 30% less use of chlorine. Structural analysis of enzyme-treated pulp showed dissolution of hemicellulose as indicated by pores, cracks and increased roughness all over the surface. Cocktail of X + M produced economically in a single fermentation having all the requisite characteristics for pulp biobleaching is a highly suitable candidate for application in the pulp and paper industry., Environmental Science; Biological Sciences; Microbiology; Biotechnology; Enzymology; Biobleaching; Co-culturing, Mannanase; Optimization; Solid-state fermentation; Xylanase.

The aim of this study was to evaluate the biosynthesis of flavor compounds from rice bran by fermentation facilitated by Kluyveromyces marxianus and Debaryomyces hansenii. The growth of both yeasts was assessed by specific growth rates and doubling time. The biosynthesis of flavor compounds was evaluated by gas chromatography-olfactometry (GC-O), gas chromatography-mass spectrometry (GC-MS), and Spectrum (TM) sensory analysis. The specific growth rate (mu) and doubling time (t(d)) of K. marxianus was calculated as 0.16/h and 4.21h, respectively, whereas that of D. hansenii was determined as 0.13/h and 5.33h, respectively. K. marxianus and D. hansenii produced significant levels of higher alcohols and acetate esters from rice bran. Results showed that K. marxianus can produce 827.27 mu g/kg of isoamyl alcohol, 169.77 mu g/kg of phenyl ethyl alcohol, and 216.08 mu g/kg of phenyl ethyl acetate after 24-h batch fermentation. A significant amount of isovaleric acid was also synthesized by K. marxianus (4013 mu g/kg) after the batch fermentation of 96 h. 415.64 mu g/kg of isoamyl alcohol and 135.77 mu g/kg of phenyl ethyl acetate was determined in rice bran fermented by D. hansenii after 24-h fermentation. Fermented cereals and rose were the characteristic flavor descriptors of the fermented rice bran samples. Rose flavor in fermented rice bran samples was found to be associated with phenyl ethyl alcohol, phenyl ethyl acetate, isoamyl acetate, and guaiacol. Thus, the findings of this study demonstrate that the valorization of rice bran can be achieved with the production of natural flavor compounds by yeast metabolism., Scientific and Technological Council of Turkey (TUBITAK, Ankara Turkey) [110O903], This study was supported by The Scientific and Technological Council of Turkey (TUBITAK, Ankara Turkey; Project No. 110O903).

Agro-food industries face the challenge of re-using their wastes following the circular economy concept. The co-bioprocessing of wastes produced by different agro-food industries located in the same region can be a suitable strategy for the valorization of these wastes. This work evaluated the use of mixtures of wastes from wineries, olive mill and breweries to produce lignocellulolytic enzymes and antioxidant compounds by Aspergillus niger under solid-state fermentation (SSF). The SSF of a mixture of brewery spent grain with crude and exhausted olive pomace led to the highest values of enzymatic activity (xylanase, 837 U/g, cellulase, 87 U/g; -glucosidase, 254 U/g), being higher than enzymes activities per mass of total substrates. The highest antioxidant activity was achieved after 1 day of fermentation, being 2.3-fold higher in comparison to the unfermented wastes. SSF allowed the co-management of agro-industrial wastes from different industries., Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTec-Norte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte, info:eu-repo/semantics/publishedVersion

The present research work is about the production and process optimization of pectinase enzyme using substrateFicus religiosaleaves byAspergillus awamoriin solid state fermentation. Pectinase having various applications in food industry such as fruit juice extraction, coffee and tea fermentation, textile, paper and pulp industries and in waste-water treatment. Solid-state fermentation is described as a process that take place on a non-soluble material that performs both as support and a source of nutrients, with a reduced among of water, under the action of fermenting agent. Parametric evaluations like time, temperature, size of inoculum, pH and moisture content were optimized to induce the high yield of pectinase. The increased level of pectinase enzyme production was detected at time 72 hrs, temperature 30 °C, optimum inoculum level was 50% v/w, pH 5 and 60 % v/w moisture content of the substrate were best for the maximum production of pectinase in solid-state condition. A remarkable enzyme production was enhanced and recorded when the basal medium was supplemented with carbon (4% glucose) and nitrogen (ammonium sulphate, 0.4%) sources.&nbsp

An efficient processing of organic solid residues will be pivotal in the development of the circular bioeconomy. Due to their composition, such residues comprise a great biochemical conversion potential through fermentations. Generally, the carbohydrates and proteins present in the organic wastes cannot be directly metabolized by microorganisms. Thus, before fermentation, enzymes are used in a hydrolysis step to release digestible sugars and nitrogen. Although enzymes can be efficiently produced from organic solid residues in solid-state fermentations (SsF), challenges in the development and scale-up of SsF technologies, especially bioreactors, have hindered a wider application of such systems. Therefore, most of the commercial enzymes are produced in submerged-liquid fermentations (SmF) from expensive simple sugars. Instead of independently evaluating SsF and SmF, the review covers the option of combining them in a sequential process in which, enzymes are firstly produced in SsF and then used for hydrolysis, yielding a suitable medium for SmF. The article reviews experimental work that has demonstrated the feasibility of the process and underlines the benefits that such combination has. Finally, a discussion is included which highlights that, unlike typically perceived, SsF should not be considered a counterpart of SmF but, in contrast, the main advantages of each type of fermentation are accentuated in a synergistic sequential SsF-SmF.

Solid-state fermentation requires the development of more efficient cultivation systems for its industrial application. The objective of this work was to evaluate the effect of aeration regime on the production of biomass and several lignocellulolytic enzymes (laccase, manganese peroxidase, endoxylanase, β-glucosidase, and total cellulases) by Trametes versicolor in a novel fixed-bed solid-state pilot-scale bioreactor. Three regimes were assessed: natural convection, low aeration level (10 min every 6 h at 10 L/h air flowrate), and high aeration level (1 h every 6 h at 10 L/h air flowrate). The mushroom was grown on a medium based on lignocellulosic residues. The design of the bioreactor, as well as the control of aeration, humidity, and temperature of the beds, allowed T. versicolor to grow properly on the medium, reaching a maximum biomass production of 204.7 mg/g dry solid (ds). The influence that aeration regime had on the production of lignocellulolytic enzymes was determined. Low level of forced aeration favored obtaining the highest titers of laccase (6.37 U/g ds) compared to natural convection and high aeration level. The greatest lignin degradation was also verified for low aeration regime. For the first time, pilot scale cultivation of T. versicolor was reported in a fixed-bed bioreactor.

An α-L-Rhamnosidase released by Aspergillus niger during solid-state fermentation (SSF) using coffee pulp (CP) wastes media has been investigated. The activity of α-L-Rhamnosidase based on reducing sugar production against 2% CP alkali extract substrate in 50 mM acetate buffer pH 5. The maximum activity of α-L-Rham-nosidase was obtained in sixth-day SSF with reducing sugar pro-duction of 13 μg/mL. The enzyme is actively hydrolyzed 0.1% p-ni-trophenyl-α-L-rhamnopyranoside (PNP-Rha) to 95% from initial concentration. Purification using DEAE-Toyopearl 650M increased hydrolysis activity ten times against the substrate, reaching 134 μg/mL of reducing sugar. Optimum enzyme activity at pH 4.5 and 50°C, while stable at pH and temperature in a pH range of 3.5-7 and below 50°C.

A low-energy paradigm was adopted for sustainable, affordable, and effective urban waste valorization. Here a new, eco-designed, solid-state fermentation process is presented to obtain some useful bio-products by recycling of different wastes. Urban food waste and scraps from trimmings were used as a substrate for the production of citric acid (CA) by solid state fermentation of Aspergillus niger NRRL 334, with a yield of 20.50 mg of CA per gram of substrate. The acid solution was used to extract metals from waste printed circuit boards (WPCBs), one of the most common electronic waste. The leaching activity of the biological solution is comparable to a commercial CA one. Sn and Fe were the most leached metals (404.09 and 67.99 mg/L, respectively), followed by Ni and Zn (4.55 and 1.92 mg/L) without any pre-treatments as usually performed. Commercial CA extracted Fe more efficiently than the organic one (123.46 vs. 67.99 mg/L), vice versa, biological organic CA recovered Ni better than commercial CA (4.55 vs. 1.54 mg/L). This is the first approach that allows the extraction of metals from WPCBs through CA produced by A. niger directly grown on waste material without any sugar supplement. This “green” process could be an alternative for the recovery of valuable metals such as Fe, Pb, and Ni from electronic waste.

Pectinases are enzymes responsible for cleaving pectin and other pectic polysaccharides in galacturonic acid monomers. They are widely applied in industrial sectors. In this context, the present study evaluated polygalacturonase (PG), pectin lyase (PMGL) and FPase production by Aspergillus niger IOC 4003 in solid-state fermentation using yellow mombin pulp residue as substrate. Three parameters were investigated for extraction of PG such as temperature, pH stability and ionic strength. The action of PG was assessed under different states of temperature and pH as well in yellow mombin juice clarification. The antibacterial activity of yellow mombin juice was additionally evaluated. Results revealed that the highest yield of PG produced (38.22 ± 0.63 U/g) was achieved at 72 h fermentation using washed yellow mombin pulp residue. Characterization studies indicated stability of PG for 2 h at 30 and 40 °C with pHs between 4 and 6. The PG applied in the yellow mombin was able to reduce turbidity by 41% and viscosity by 52%. Also, it was able to increase color by 36% and antioxidant capacity by 39%. Finally, the yellow mombin juice exhibited antibacterial activity against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Klebsiella pneumoniae. Hence, this study demonstrated the feasibility of using tropical fruit residues from industries for pectinases synthesis and showed their application in the food industry.

Made available in DSpace on 2019-10-06T16:59:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-04-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Mathematical models can be useful to predict the behavior of particulate systems, as it is the case of packed-bed bioreactors (PBBs) used for solid-state fermentation (SSF). The models also simplify the processes scale-up, and depending on the accuracy of the model, critical parameters can be predicted, as temperature, moisture content and maximum bed height. In the current paper, mathematical models and simulations were used to predict the optimal conditions for enzymes production by means of SSF in PBBs. Two models available in literature were applied: a recently proposed two-phase and two-dimensional (2-D) model and a modified Damköhler number (Dam) approach, considering maximum temperatures of the bed and maximum bed height to allow good production of enzymatic activities by the fungus Myceliophtora thermophila I-1D3b. Based on simulation results, experiments in bench and pilot-scale PBBs were performed and analyzed. By comparing experimental and simulated results of temperatures, the 2-D model showed to be more accurate than Dam approach. Despite of the temperature increase in pilot-scale PBB, the bioreactor scale-up with the fungus M. thermophila in substrate composed of sugarcane bagasse (SCB) and wheat bran (WB) (weight proportion 7:3) could be considered as feasible for cellulolytic and xylanolytic enzymes provision, for instance, for second generation ethanol production chain, although issues related to airflow distribution and substrate shrinkage in pilot-scale PBB must still be further overcome. Food Engineering and Technology Department Institute of Biosciences Letters and Exact Sciences São Paulo State University (UNESP), Cristóvão Colombo 2265, Jardim Nazareth Chemical Engineering Department Federal University of São Carlos (UFSCar), Rod. Washington Luís km 235 – SP-310 Food Engineering and Technology Department Institute of Biosciences Letters and Exact Sciences São Paulo State University (UNESP), Cristóvão Colombo 2265, Jardim Nazareth FAPESP: 2014/23453-3

This article studies the environmental impacts of cellulase production by using a comparative attributional life cycle assessment (LCA) of two different scenarios of production. The first one is the commonly used submerged fermentation (SmF) using a pure substrate (cellulose powder) and a specific microorganism (Trichoderma reesei). The second scenario considers a novel system to produce enzymes and simultaneously treat a waste using the solid-state fermentation (SSF) process of coffee husk (CH) used as substrate. Experimental data were used in this scenario. The complete production process was studied for these two technologies including the fermentation phase and the complete downstream of cellulase. Life cycle inventory (LCI) data were collected from the database EcoInvent v3 (SimaPro 8.5) modified by data from literature and pilot scale experiments. The environmental impacts of both production systems revealed that those of SmF were higher than those of SSF. A sensitivity analysis showed that the results are highly conditioned by the energy use in the form of electricity during lyophilization, which is needed in both technologies. The results point to a possible alternative to produce the cellulase enzyme while reducing environmental impacts.

In this study, spent coffee waste (SCW) was used as the sole carbon source for xylanase production in solid state fermentation mode using Aspergillus niger. A Box&ndash, Behnken design was constructed using three parameters viz. temperature, initial moisture content, and log number of spores to determine the optimal fermentation condition. The best fermentation conditions for xylanase production were found to be incubation at 30 &deg, C with an initial moisture content of 70% and using an inoculum of 6.5 &times, 106 spores/g of dry SCW. Furthermore, the design of experiments revealed that maintaining a medium composition of 0.2 g of yeast extract, 0.04 g of K2HPO4, and 0.03 g of MgSO4 increased xylanase production. Under optimised solid-state fermentation conditions an enzyme activity of 6495.6 IU/g of dry SCW was recorded, which was approximately 1.39-fold higher than that of control (4649 IU/g of dry SCW). The efficacy of the purified xylanase as a juice enrichment agent for strawberry, blueberry, and raspberry pulp was tested.

In this study, coffee pulp was used as carbon source in solid-state fermentation to produce a phenol-rich extract for industrial applications. Fermentations were carried out at laboratory (0.4 kg), semi-pilot (12 kg) and pilot (90 kg) scales in presence of 2.5 g kg−1 yeast strains and with three different coffee pulp materials. The extract stability was investigated using different stabilizing agents: SO2, ascorbic and acetic acids. Then, a study was conducted to determine the effect of ultrasound treatment on extraction yields. Results showed that higher concentrations of chlorogenic acids were obtained with fermentation without ultrasound treatment and by adding sulfite at 0.5 wt% at 8 h of fermentation. Despite of variations in coffee pulp composition, the process was validated at semi-pilot and pilot scales, providing an extract 400% richer in chlorogenic acids (600 mg kg of coffee pulp) and with lower sugar amounts to separate during the downstream processing. Universidad de Costa Rica/[735-A2-502]/UCR/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA)

This work systematically studies the downstream process of the solid state fermentation (SSF) of a mixture of coffee husk and wood chips, inoculated with compost, for cellulase production. Downstream of SSF (at pilot scale) remains as one of the less studied stages of the process, being critical in technical, environmental and economic terms. In this study, the specific downstream points considered were: (i) enzyme extraction yield, in terms of extraction ratio solid:solvent, agitation mode and solvent type; (ii) enzymatic activity recovery of the lyophilised extract and (iii) efficiency of consecutive extractions. Results indicate a maximum activity recovery of 108 ± 30% in the extraction performed at ratio 1:5 solid-solvent, in static mode and with distilled water. Statistical analysis revealed a high dispersion of the results and needs to be considered to extract consistent conclusions in any downstream of SSF. Lyophilisation demonstrated to be an adequate technology for enzymatic activity preservation. Regarding consecutive extractions, yield recovery in the first and second extraction maintain a similar value. In a framework of a zero-waste enzyme production process, different strategies have been tested for the remaining solid after extraction. Respirometric tests reveal that it is possible to aerobically stabilize the remaining solid obtaining a compost like material, whereas anaerobic digestion resulted in low methane yields (51 ± 3 mL methane g−1 VS).

The cost of cellulases is the main bottleneck for bioethanol production at commercial scale. Solid-state fermentation (SSF) is a promising technology that can potentially reduce cellulases cost by using wastes as substrates. In this work, a SSF system of 4.5 L bioreactors was operated continuously by sequential batch operation using the fermented solids from one batch to inoculate the following batch. Coffee husk was used as lignocellulosic substrate. Compost was used as starter in the first batch to provide a rich microbiota. Two strategies were applied: using 10% fermented solids as inoculum in 48 h batches (SB90) and using 50% solids in 24 h batches (SB50). A consistent and robust production process was achieved by sequential batch operation. Similar cellulase activities around 10 Filter Paper Units per gram of dry solids were obtained through both strategies. Microbial diversity in the starting materials and in the final fermented solids was characterized by next generation sequencing. Microbial composition of both fermented solids was similar but the relative abundance of families and species was affected by the operation strategy used. Main bacteria in the final solids came from compost (families Sphingobacteriaceae, Paenibacillaceae and Xanthomonadaceae), while main fungi families came from coffee husk (families Phaffomycetaceae, Dipodascaceae and two unidentified families of the class of Tramellomycetes). There was a high presence of non-identified mycobiota in the fermented solids. Main identified species were the bacteria Pseudoxanthonomas taiwanensis (12.3% in SB50 and 6.1% in SB90) and Sphingobacterium composti (6.1% in SB50 and 2.6% in SB90) and the yeasts Cyberlindnera jardinii and Barnettozyma californica (17.8 and 4.1% respectively in SB50 and 34 and 9.1% in SB90), all four previously described as lignocellulose degraders. The development of these operational strategies and further biological characterization of the end product could eventually benefit the process economics by providing a standard and specialized inoculum for a continuous SSF for cellulases production.

2-Phenylethanol (2-PE) and 2-phenethyl acetate (2-PEA) are important aroma compounds widely used in food and cosmetic industries due to their rose-like odor. Nowadays, due to the growing demand for natural products, the development of bioprocesses for obtaining value-added compounds has become of great significance. 2-PE and 2-PEA can be produced through the biotransformation of L-phenylalanine using the generally recognized as safe strain Kluyveromyces marxianus. L-phenylalanine bioconversion systems have been typically focused on submerged fermentation processes (SmF), but there is no information about other alternative productive approaches. Here, the solid-state fermentation (SSF) of sugarcane bagasse supplemented with L-phenylalanine was investigated as a sustainable alternative for producing 2-PE and 2-PEA in a residue-based system using Kluyveromyces marxianus as inoculum. An initial screening of the operational variables indicated that air supply, temperature, and initial moisture content significantly affect the product yield. Besides, it was found that the feeding strategy also affects the production and the efficiency of the process. While a basic batch system produced 16 mgproducts per gram of residue (dry basis), by using split feeding strategies (fed-batch) of only sugarcane bagasse, a maximum of 18.4 mgProducts g-1residue were achieved. Increase in product yield was also accompanied by an increase in the consumption efficiency of nutrients and precursor. The suggested system results as effective as other more complex SmF systems to obtain 2-PE and 2-PEA, showing the feasibility of SSF as an alternative for producing these compounds through the valorization of an agro-industrial residue.

Filamentous fungi are considered to be the most important group of microorganisms for the production of plant cell wall degrading enzymes (CWDE), in solid state fermentations. In this study, two fungal strains Aspergillus niger MS23 and Aspergillus terreus MS105 were screened for plant CWDE such as amylase, pectinase, xylanase and cellulases (β-glucosidase, endoglucanase and filterpaperase) using a novel substrate, Banana Peels (BP) for SSF process. This is the first study, to the best of our knowledge, to use BP as SSF substrate for plant CWDE production by co-culture of fungal strains. The titers of pectinase were significantly improved in co-culture compared to mono-culture. Furthermore, the enzyme preparations obtained from monoculture and co-culture were used to study the hydrolysis of BP along with some crude and purified substrates. It was observed that the enzymatic hydrolysis of different crude and purified substrates accomplished after 26 h of incubation, where pectin was maximally hydrolyzed by the enzyme preparations of mono and co-culture. Along with purified substrates, crude materials were also proved to be efficiently degraded by the cocktail of the CWDE. These results demonstrated that banana peels may be a potential substrate in solid-state fermentation for the production of plant cell wall degrading enzymes to be used for improving various biotechnological and industrial processes.

Aims: Enzyme (cellulase) contributes 10% to overall cost in bioethanol production from lignocellulosic biomass. This means that the cost for bioethanol production will be reduced if cellulase can be produced using cheaper method. Compared with submerged fermentation, it is recognized that the cost for cellulase production using solid state fermentation (SSF) process is much cheaper. The present study aimed to optimize cellulase production via SSF process using agro-industrial residual as substrate. Methodology and result: Newly developed solid state bioreactor, FERMSOSTAT had been evaluated in cellulase production using local isolate Aspergillus niger USM AI 1 grown on sugarcane baggase and palm kernel cake as substrates at 1:1 (w/w) ratio. Under optimized SSF conditions of 0.5 kg substrate; 70% (w/w) moisture content; 30 °C; aeration at 4 L/h.g fermented substrate for 5 min and mixing at 0.5 rpm for 5 min, about 62.6 U/g of CMCase activity obtained. At the same time, comparative studies of the enzyme production under the same SSF conditions indicated that CMCase produced by Trichoderma reesei was about 9% lower compared with A. niger USM AI 1. Conclusion, significance and impact of study: It can be concluded that the performance of newly developed SSF fermenter is good since it can used to produce CMCase enzyme with reasonable good title (863% increased in CMCase production after optimization). Thus, this newly developed SSF bioreactor has highly potential be used as prototype for larger scale bioreactor design.

Bioprocess development studies concerning the production of cellulases are of crucial importance due to the significant impact of these enzymes on the economics of biomass conversion into fuels and chemicals. This work evaluates the effects of solid-state fermentation (SSF) operational conditions on cellulase production by a novel strain of Aspergillus oryzae using an instrumented lab-scale bioreactor equipped with an on-line automated monitoring and control system. The use of SSF cultivation under controlled conditions substantially improved cellulase production. Highest production of FPase (0.40 IU g-1), endoglucanase (123.64 IU g-1), and β-glucosidase (18.32 IU g-1) was achieved at 28 °C, using an initial substrate moisture content of 70%, with an inlet air humidity of 80% and an airflow rate of 20 mL min-1. Further studies of kinetic profiles and respirometric analyses were performed. The results showed that these data could be very useful for bioprocess development of cellulase production and scale-up.

Hair wastes from the tannery industry were assessed for its suitability as substrates for protease production by solid-state fermentation (SSF) using a pilot-batch mode operation and anaerobically digested sludge as co-substrate. Maximum protease activity (52,230 ± 1601 U g −1 DM) was observed at the 14th day of SSF. Single step purification resulted in 2 fold purification with 74% of recovery by ultrafiltration with 10 kDa cut-off. The recovered enzyme was stable at a temperature of 30 °C and pH 11; optimal conditions that were determined by a central composite full factorial experimental design. The enzyme activity was inhibited by phenylmethylsulfonyl fluoride, which indicates that it belongs to serine protease group. The remaining solid material after protease extraction could be easily stabilized to obtain a final good quality compost-like material as the final dynamic respiration index was lower than 1 g O 2 kg −1 OM h −1 . The lyophilized recovered enzymes were a good alternative in the process of cowhides dehairing with respect to the current chemical treatment, avoiding the production of solid wastes and highly polluted wastewaters. In conclusion, the entire process can be considered a low-cost sustainable technology for the dehairing process, closing the organic matter cycle in the form of value added product and a compost-like material from a waste.

Biosorption of dyes by lignocelluloses may be an effective method for removing dyes from textile effluents. However, the resulting dye-adsorbed lignocellulosic materials may constitute another pollution problem. An integrated method can solve this problem. Here, various lignocelluloses were tested for their Astrazon Black and Astrazon Blue dyes removal activities. The dye adsorbed after 30 min contact time was 90% (45 mg/L), 70% (35 mg/L), and 98% (49 mg/L) for wheat bran, pine cone, and cotton stalk, respectively. These dye-adsorbed lignocellulosic wastes then were used as solid substrates to produce laccase enzyme with Funalia trogii and Trametes versicolor under solid state fermentation (SSF). Among the lignocellulosic substrates, the dye-adsorbed wheat bran served as the best solid substrate for laccase production under SSF. Therefore, it was also tested as a solid source for laccase production under submerged fermentation. During solid state fermentation, these two fungi were able to highly decolorize these dyes. While F. trogii decolorized 80% of Astrazon Black dye adsorbed onto wheat bran, T. versicolor decolorized 86%. On the other hand, the decolorization values for Astrazon Blue dye were 69% and 84%, respectively.

Soybean meal (SBM), a commonly used protein source for animal feed, contains anti-nutritional factors such as trypsin inhibitor, phytate, oligosaccharides among others, which limit its utilization. Microbial fermentation using bacteria or fungi has the capability to improve nutritional value of SBM by altering the native composition. Both submerged and solid state fermentation processes can be used for this purpose. Bacterial and fungal fermentations result in degradation of various anti-nutritional factors, an increase in amount of small-sized peptides and improved content of both essential and non-essential amino acids. However, the resulting fermented products vary in levels of nutritional components as the two species used for fermentation differ in their metabolic activities. Compared to SBM, feeding non-ruminants with fermented SBM has several beneficial effects including increased average daily gain, improved growth performance, better protein digestibility, decreased immunological reactivity and undesirable morphological changes like absence of granulated pinocytotic vacuoles. received: 2015-07-27 accepted: 2015-12-01 published: 2015-12-01 ispartof: Asian-Australasian Journal of Animal Sciences vol:29 issue:11 pages:1523-1529 ispartof: location:Korea (South) status: Published online

Being eco-friendly, less toxic, more biodegradable and biocompatible, biological surfactants have higher activity and stability compared to synthetic ones. In spite of the fact that there are abundant benefits of biosurfactants over the synthetic congeners, the problem related with the economical and large scale production proceeds. The utilization of several industrial wastes in the production media as substrates reduces the production cost. This current study aims optimization of biosurfactant production conditions by Pleurotus djamor, grown on sunflower seed shell, grape wastes or potato peels as renewable cheap substrates in solid state fermentation. After determination of the best substrate for biosurfactant production, we indicate optimum size and amount of solid substrate, volume of medium, temperature, pH and Fe2+ concentrations on biosurfactant production. In optimum conditions, by reducing water surface tension to 28.82 +/- 03 mN/m and having oil displacement diameter of 3.9 +/- 0.3 cm, 10.205 +/- 0.5 g/l biosurfactant was produced. Moreover, chemical composition of biosurfactant produced in optimum condition was determined by FTIR. Lastly, laboratory's large-scale production was carried out in optimum conditions in a tray bioreactor designed by us and 8.9 +/- 0.5 g/l biosurfactant was produced with a significant surface activity (37.74 +/- 0.3 mN/m). With its economical suggestions and applicability of laboratory's large-scale production, this work indicates the possibility of using low cost agro-industrial wastes as renewable substrates for biosurfactant production. Therefore, using economically produced biosurfactant will reduce cost in several applications such as bioremediation, oil recovery and biodegradation of toxic chemicals. (C) 2015, The Society for Biotechnology, Japan. All rights reserved.

Gamma linolenic acid (GLA, 18:3, cis- 6,9,12- octadecatrienoic acid), an important compound in n- 6 eicosanoid family biosynthesis, occurs in the lipids of a few plant and microbial sources. This study focused on the screening of microbial strains with suitable lipase activity for enrichment of GLA by selective hydrolysis of the borage oil (21.6 % of GLA/total fatty acids). Firstly, 352 microrganisms were tested for their lipolytic capacity using screening techniques on agar plates containing borage oil, strains were then selected and screened for their activity (U/mg) using both submerged fermentation (SmF) and solid state fermentation (SSF). The rate of hydrolysis and the selective preference of these hydrolytic enzymes towards fatty acids, with a special focus on enrichment of GLA were studied and compared with those obtained by two commercially-available lipases. Only one of the lipases tested during this study displayed selectivity, discriminating the GLA during the hydrolysis reaction. Using the enzymatic extract from Geotrichum candidum as a biocatalyst of the reaction, it was possible to obtain a percentage of 41.7% of GLA in acylglycerols fraction when the borage oil was treated in a fixed-bed reactor for 24 hours at 30oC.

Wineries and olive oil industries are dominant agro-industrial activities in southern European regions. Olive pomace, exhausted grape marc and vine shoot trimmings are lignocellulosic residues generated by these industries, which could be valued biotechnologically. In the present work these residues were used as substrate to produce cellulases and xylanases through solid-state fermentation using Aspergillus uvarum. For that, two factorial designs (32) were first planned to optimize substrate composition, temperature and initial moisture level. Subsequently, the kinectics of cellulolytic enzymes production, fungal growth and fermented solid were characterized, Finally, the process was performed in a packed-bed bioreactor. The results showed that cellulase activity improved with the optimization processes, reaching 33.56 U/g, and with the packed-bed bioreactor aeration of 0.2 L/min, reaching 38.51 U/g. The composition of fermented solids indicated their potential use for animal feed because cellulose, hemicellulose, lignin and phenolic compounds were partially degraded 28.08, 10.78, 13.3 and 28.32% respectively, crude protein was increased from 8.47% to 17.08%, and, the mineral contents meet the requirements of main livestock., J.M.S. was supported by Grant SFRH/BPD/84440/2012 from Fundacao para a Ciencia e Tecnologia (FCT), Portugal. L.A. was supported by Grant Incentivo/EQB/LA0023/2014 from O Novo Norte (ON.2). We thank FCT Strategic Project PEst-OE/EQB/LA0023/2013 and the Project "BioInd - Biotechnology and Bioengineering for improved Industrial and Agro-Food processes, Rer. NORTE-07-0124-FEDER-000028" co-funded by the Programa Operacional Regional do Norte (ON.2), QREN, FEDER

Citric acid is commercailly important product used in several industrial processes. Solid-state fermentation (SSF) has become an alternative method for citric acid production using agro-industrial residues such as cassava bagasse (CB). Use of CB as substrate can avoid the environmental problems caused by its disposal in the environment. The aim of this work was to verify the effect of different percentages of gelatinized starch in CB on production of citric acid by SSF in horizontal drum and tray-type bioreactors. Gelatinization was used in order to make the starch structure more susceptible to consumption by the fungus. The best results (26.9 g/100g of dry CB) were obtained in horizontal drum bioreactor using 100% gelatinized CB, although the tray-type bioreactor offers advantages and shows promise for large-scale citric acid production in terms of processing costs.

Most of the freshwater systems in tropical countries are infested with one kind of aquatic weed or the other causing serious environmental problems. All efforts to control the growth and spread of these weeds have failed miserably and hence the concept of eradication through utilization is being adopted by many researchers. Solid state fermentation, the culturing of microorganisms on moist solid substrates in the absence or near absence of free water, has generated great deal of interest among researchers because of its various advantages over the submerged fermentation technique. Cellulase enzyme is used extensively in various industries, especially in textile, food and in the bioconversion of lignocellulosic wastes to alcohol. The extensive use of cellulase in industries depends on the cost of the enzyme and hence considerable research is being carried out to isolate better microbial strains and also to develop new fermentation processes with the aim to reduce the product cost. The objective of the present study is to determine whether water hyacinth, one of the commonly found aquatic weeds, can be used as a substrate for cellulase production, by three native bacterial isolates named WHB 3, WHB 4 and SMB 3, under the process of solid state fermentation. Results indicate that all the three isolates produced cellulase enzyme by using water hyacinth as the solid support. Under optimized conditions of moisture, pH, temperature, incubation time and inoculum concentration, the enzyme yield increased from 16.8 to 94.8 units for SMB 3, from 25.2 to 110.4 units for WHB 3 and from 18.0 to 127.2 units for WHB 4. The addition of nitrogen and carbon sources resulted in a significant increase in cellulase yield and WHB 3 produced the maximum amount of 216 units followed by SMB 3 and WHB 4.

A simplified model to describe fungal growth during citric pulp fermentation for phytase production was described for the first time. Experimental data for biomass growth were adjusted to classical mathematical growth models (Monod and Logistic). The Monod model predictions showed good agreement with the experimental results for biomass concentration during 96 hours of fermentation. Parameters such as yield of biomass from oxygen (Y X/O), maintenance coefficient (m) and specific growth rate (µ) were compared showing a good correlation between the data and the model. An alternative method for biomass determination in this process was developed since a great correlation was found between biomass growth and enzyme formation.Um modelo simplificado para descrever o crescimento fúngico durante a fermentação em polpa citric para a produção da fitase foi descrita pela primeira vez. Dados experimentais para a formação de biomassa foram ajustados a modelos clássicos de crescimento microbiano (Monod e Logístico). O modelo Monod previsto mostrou boa correlação aos resultados experimentais para a concentração de biomassa até 96 horas de fermentação. Parâmetros como rendimento de biomassa a partir de oxigênio (Y X/O), coeficiente de manutenção (m) e taxa específica de crescimento (µ) foram comparados mostrando uma boa correlação entre os dados e o modelo. Um método alternativo para a determinação de biomassa neste processo foi desenvolvido a partir de uma excelente correlação encontrado entre o crescimento microbiano e a formação da enzima.

Mustard oil cake (Brassica napus), the residue obtained after extraction of mustard oil from mustard oil seeds, was investigated for the production of lipase under solid state fermentation (SSF) using the marine yeast Yarrowia lipolytica NCIM 3589. Process parameters such as incubation time, biomass concentration, initial moisture content, carbon source concentration and nitrogen source concentration of the medium were optimized. Screening of ten nitrogen and five carbon sources has been accomplished with the help of Plackett-Burman design. The highest lipase activity of 57.89 units per gram of dry fermented substrate (U/gds) was observed with the substrate of mustard oil cake in four days of fermentation.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:41:35Z No. of bitstreams: 1 S1517-83822013000100034.pdf: 1361311 bytes, checksum: bc10dd06b6d6bd393d34cb4538983256 (MD5) Made available in DSpace on 2013-08-22T18:41:35Z (GMT). No. of bitstreams: 1 S1517-83822013000100034.pdf: 1361311 bytes, checksum: bc10dd06b6d6bd393d34cb4538983256 (MD5) Previous issue date: 2013-01-01 Made available in DSpace on 2013-09-30T19:28:11Z (GMT). No. of bitstreams: 2 S1517-83822013000100034.pdf: 1361311 bytes, checksum: bc10dd06b6d6bd393d34cb4538983256 (MD5) S1517-83822013000100034.pdf.txt: 34995 bytes, checksum: d91a7f24c43ad09e5bdda2089fa5f05a (MD5) Previous issue date: 2013-01-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:07:45Z No. of bitstreams: 2 S1517-83822013000100034.pdf: 1361311 bytes, checksum: bc10dd06b6d6bd393d34cb4538983256 (MD5) S1517-83822013000100034.pdf.txt: 34995 bytes, checksum: d91a7f24c43ad09e5bdda2089fa5f05a (MD5) Made available in DSpace on 2014-05-20T15:07:45Z (GMT). No. of bitstreams: 2 S1517-83822013000100034.pdf: 1361311 bytes, checksum: bc10dd06b6d6bd393d34cb4538983256 (MD5) S1517-83822013000100034.pdf.txt: 34995 bytes, checksum: d91a7f24c43ad09e5bdda2089fa5f05a (MD5) Previous issue date: 2013-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Enzyme production varies in different fermentation systems. Enzyme expression in different fermentation systems yields important information for improving our understanding of enzymatic production induction. Comparative studies between solid-state fermentation (SSF) using agro-industrial waste wheat bran and submerged fermentation (SmF) using synthetic media were carried out to determinate the best parameters for peptidase production by the fungus Aspergillus fumigatus Fresen. Variables tested include: the concentration of carbon and protein nitrogen sources, the size of the inoculum, the pH of the media, temperature, and the length of the fermentation process. The best peptidase production during SSF was obtained after 96 hours using wheat bran at 30 ºC with an inoculum of 1 x 10(6) spores and yielded 1500 active units (UµmL). The best peptidase production using SmF was obtained after periods of 72 and 96 hours of fermentation in media containing 0.5% and 0.25% of casein, respectively, at a pH of 6.0 and at 30 ºC and yielded 40 UµmL. We also found examples of catabolite repression of peptidase production under SmF conditions. Biochemical characterization of the peptidases produced by both fermentative processes showed optimum activity at pH 8.0 and 50 ºC, and also showed that their proteolytic activity is modulated by surfactants. The enzymatic inhibition profile using phenylmethylsulfonyl fluoride (PMSF) in SmF and SSF indicated that both fermentative processes produced a serine peptidase. Additionally, the inhibitory effect of the ethylene-diaminetetraacetic acid (EDTA) chelating agent on the peptidase produced by SmF indicated that this fermentative process also produced a metallopeptidase. Universidade Estadual Paulista Júlio de Mesquita Filho Instituto de Biociências, Letras e Ciências Exatas Centro Universitário da Fundação Educacional de Barretos Faculdade de Farmácia Universidade Estadual Paulista Júlio de Mesquita Filho Departamento de Bioquímica e Microbiologia Universidade de São Paulo Faculdade de Ciências Farmacêuticas de Ribeirão Preto Departamento de Bioquímica e Microbiologia, Universidade Estadual Paulista "Júlio de Mesquita Filho", Rio Claro, SP, Brazil Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista "Júlio de Mesquita Filho", São José do Rio Preto, SP, Brazil

The production of lipids by oleaginous yeast and fungi becomes more important because these lipids can be used for biodiesel production. To understand the process of lipid production better, we developed a model for growth, lipid production and lipid turnover in submerged batch fermentation. This model describes three subsequent phases: exponential growth when both a C-source and an N-source are available, carbohydrate and lipid production when the N-source is exhausted and turnover of accumulated lipids when the C-source is exhausted. The model was validated with submerged batch cultures of the fungus Umbelopsis isabellina (formerly known as Mortierella isabellina) with two different initial C/N-ratios. Comparison with chemostat cultures with the same strain showed a significant difference in lipid production: in batch cultures, the initial specific lipid production rate was almost four times higher than in chemostat cultures but it decreased exponentially in time, while the maximum specific lipid production rate in chemostat cultures was independent of residence time. This indicates that different mechanisms for lipid production are active in batch and chemostat cultures. The model could also describe data for submerged batch cultures from literature well.

Brazil is known for its great potential for production of renewable resources such as agro-industrial residues. These residues can be used as alternative sources of new products. Meanwhile, solid-state fermentation, with its advantages of energy conservation and pollution reduction, has been identified as a process of great potential for the production of bioactive compounds, especially enzymes. In the present work, a 2(3) factorial design was used to evaluate the effects of pH, temperature and moisture on the production of phytase and xylanase by Lichtheimia blakesleeana URM 5604 through the fermentation of citrus pulp. Statistical analyses of the results showed that the only the pH influenced the production of these enzymes, with the best phytase production (264.68 U/g) ocurring at pH 6.0, 34 °C, initial moisture 50%, after 48 hours of culture. The best conditions for xylanase production (397.82 U/g) were fermentation for 120 hours at pH 4.0, 26 °C and initial moisture of 70%. The best parameters for the simultaneous production of phytase (226.92 U/g) and xylanase (215.59 U/g) were determined to be initial moisture of 50%, pH 6.0, 26 °C, and 48 hours of fermentation.

Citric acid is the most important organic acid produced in tonnage and is extensively used in food and pharmaceutical industries. It is produced mainly by submerged fermentation using Aspergillus niger or Candida sp. from different sources of carbohydrates, such as molasses and starch based media. However, other fermentation techniques, e.g. solid state fermentation and surface fermentation, and alternative sources of carbon such as agro-industrial residues have been intensively studied showing great perspective to its production. This paper reviews recent developments on citric acid production by presenting a brief summary of the subject, describing micro-organisms, production techniques, and substrates, etc.O ácido cítrico é o ácido mais produzido em termos de tonagem e é extensivamente utilizado pelas indústrias alimentícia e farmacêutica. É produzido principalmente por fermentação submersa utilizando o fungo Aspergillus niger e leveduras do gênero Candida sp. à partir de diferentes fontes de carbono, como a glicose e meios à base de amido. No entanto, outras técnicas de fermentação, e.g. fermentação no estado sólido e em superfície, e fontes alternativas de carbono tem sido intensamente estudadas mostrando grande perspectivas para o processo. O presente trabalho apresenta um resumo dos últimos avanços sobre a produção do ácido cítrico, descrevendo de maneira sucinta os trabalhos mais recentes, descrevendo microrganismos, técnicas de produção e substratos empregados, etc.

7 pages, 6 figures, 1 table, In the present work, studies of glucose oxidase (GOD) production in solid-state fermentation on polyurethane foams, using mussel processing wastewaters (MPW) as culture media, were carried out. Initially, the results generated in this experimental modality were compared with those that were obtained in conventional submerged fermentation. Later on, cultures were tested in solid state with fed-batch performance, defining suitable conditions of operation. These conditions were finally corroborated in experiments with a bioreactor of own design, in which GOD production was improved 13 times regarding to the initial cultures.

The ability of three Streptomyces strains to upgrade the nutritional value of coffee pulp residues from Nicaragua in solid-state fermentation (SSF) conditions was analyzed by Py-GC/MS. The presence in these residues of compounds such as polyphenols, tannins, chlorogenic acids and caffeine prevents their utilization as domestic fodder. The characteristic pyrolysis products derived from polyphenols and polysaccharides were identified both in control and treated coffee pulp being remarkable the decrease achieved in the total polyphenols derived compounds after the growth of the strains. The analysis of these compounds demonstrated that both monomethoxy- and dimethoxy-phenols were degraded. In addition, an increase in the microbial treated coffee pulp of protein content was detected by Kjeldahl method. In summary, changes evidenced in coffee pulp treated by Streptomyces through the application of analytical pyrolysis reveal the biotechnological interest of these bacteria to upgrade a usefulness and pollutant residue to be used for feeding purposes. © 2007 Elsevier B.V. All rights reserved.

Background Bioethanol production from biomass is becoming a hot topic internationally. Traditional static solid state fermentation (TS-SSF) for bioethanol production is similar to the traditional method of intermittent operation. The main problems of its large-scale intensive production are the low efficiency of mass and heat transfer and the high ethanol inhibition effect. In order to achieve continuous production and high conversion efficiency, gas stripping solid state fermentation (GS-SSF) for bioethanol production from sweet sorghum stalk (SSS) was systematically investigated in the present study. Results TS-SSF and GS-SSF were conducted and evaluated based on different SSS particle thicknesses under identical conditions. The ethanol yield reached 22.7 g/100 g dry SSS during GS-SSF, which was obviously higher than that during TS-SSF. The optimal initial gas stripping time, gas stripping temperature, fermentation time, and particle thickness of GS-SSF were 10 h, 35°C, 28 h, and 0.15 cm, respectively, and the corresponding ethanol stripping efficiency was 77.5%. The ethanol yield apparently increased by 30% with the particle thickness decreasing from 0.4 cm to 0.05 cm during GS-SSF. Meanwhile, the ethanol yield increased by 6% to 10% during GS-SSF compared with that during TS-SSF under the same particle thickness. The results revealed that gas stripping removed the ethanol inhibition effect and improved the mass and heat transfer efficiency, and hence strongly enhanced the solid state fermentation (SSF) performance of SSS. GS-SSF also eliminated the need for separate reactors and further simplified the bioethanol production process from SSS. As a result, a continuous conversion process of SSS and online separation of bioethanol were achieved by GS-SSF. Conclusions SSF coupled with gas stripping meet the requirements of high yield and efficient industrial bioethanol production. It should be a novel bioconversion process for bioethanol production from SSS biomass.

Background Sweet sorghum is regarded as a very promising energy crop for ethanol production because it not only supplies grain and sugar, but also offers lignocellulosic resource. Cost-competitive ethanol production requires bioconversion of all carbohydrates in stalks including of both sucrose and lignocellulose hydrolyzed into fermentable sugars. However, it is still a main challenge to reduce ethanol production cost and improve feasibility of industrial application. An integration of the different operations within the whole process is a potential solution. Results An integrated process combined advanced solid-state fermentation technology (ASSF) and alkaline pretreatment was presented in this work. Soluble sugars in sweet sorghum stalks were firstly converted into ethanol by ASSF using crushed stalks directly. Then, the operation combining ethanol distillation and alkaline pretreatment was performed in one distillation-reactor simultaneously. The corresponding investigation indicated that the addition of alkali did not affect the ethanol recovery. The effect of three alkalis, NaOH, KOH and Ca(OH)2 on pretreatment were investigated. The results indicated the delignification of lignocellulose by NaOH and KOH was more significant than that by Ca(OH)2, and the highest removal of xylan was caused by NaOH. Moreover, an optimized alkali loading of 10% (w/w DM) NaOH was determined. Under this favorable pretreatment condition, enzymatic hydrolysis of sweet sorghum bagasse following pretreatment was investigated. 92.0% of glucan and 53.3% of xylan conversion were obtained at enzyme loading of 10 FPU/g glucan. The fermentation of hydrolyzed slurry was performed using an engineered stain, Zymomonas mobilis TSH-01. A mass balance of the overall process was calculated, and 91.9 kg was achieved from one tonne of fresh sweet sorghum stalk. Conclusions A low energy-consumption integrated technology for ethanol production from sweet sorghum stalks was presented in this work. Energy consumption for raw materials preparation and pretreatment were reduced or avoided in our process. Based on this technology, the recalcitrance of lignocellulose was destructed via a cost-efficient process and all sugars in sweet sorghum stalks lignocellulose were hydrolysed into fermentable sugars. Bioconversion of fermentable sugars released from sweet sorghum bagasse into different products except ethanol, such as butanol, biogas, and chemicals was feasible to operate under low energy-consumption conditions.

Phytase production by Aspergillus niger F3 by solid state fermentation (SSF) on citrus peel was evaluated at pilot scale under different aeration conditions. The best airflow intensity was 1 VkgM (Lair kg medium−1 min−1), which allowed to produce 65 units of phytases per gram in dry basis (65 Ug−1 d.b.) as it removed the metabolic heat generated by the microorganism, Agitation did not improve heat removal. Airflow intensity was considered as scale-up criterion. When the airflow intensity was maintained at 1 VkgM for SSF with 2 and 20 kg of medium, the kinetics parameters for biomass and enzyme concentration at the end of fermentation differed by less than 2. The air flow intensity was required to maintain the temperature and cool the SSF and to provide oxygen for microbial growth. Air flow intensity is a key a factor that must be considered when scale-up of SSF is attempted.

Cellulase production from lignocellulosic materials was studied in solid-state cultivation by both static and mixed techniques under nonaseptic conditions. The effects of fermentation conditions, such as moisture content, pH, temperature, and aeration, on cellulase production by Trichoderma harzianum using a mixture of wheat straw (80%) and bran (20%) were investigated. With a moisture content of 74% and a pH of 5.8., 18 IU filter paper activity and 198 IU endoglucanase activity/g initial substrate content were obtained in 66 h. The extension from static column cultivation to stirred tank reactor of 65 L capacity gave similar yields of cellulase.