Showing papers on "Solid-state fermentation published in 2013"

Comparative secretome analysis of Trichoderma asperellum S4F8 and Trichoderma reesei Rut C30 during solid-state fermentation on sugarcane bagasse

Abstract: Background The lignocellulosic enzymes of Trichoderma species have received particular attention with regard to biomass conversion to biofuels, but the production cost of these enzymes remains a significant hurdle for their commercial application. In this study, we quantitatively compared the lignocellulolytic enzyme profile of a newly isolated Trichoderma asperellum S4F8 strain with that of Trichoderma reesei Rut C30, cultured on sugarcane bagasse (SCB) using solid-state fermentation (SSF).

Optimization of β-glucosidase, β-xylosidase and xylanase production by Colletotrichum graminicola under solid-state fermentation and application in raw sugarcane trash saccharification.

Abstract: Efficient, low-cost enzymatic hydrolysis of lignocellulosic residues is essential for cost-effective production of bioethanol. The production of β-glucosidase, β-xylosidase and xylanase by Colletotrichum graminicola was optimized using Response Surface Methodology (RSM). Maximal production occurred in wheat bran. Sugarcane trash, peanut hulls and corncob enhanced β-glucosidase, β-xylosidase and xylanase production, respectively. Maximal levels after optimization reached 159.3 ± 12.7 U g−1, 128.1 ± 6.4 U g−1 and 378.1 ± 23.3 U g−1, respectively, but the enzymes were produced simultaneously at good levels under culture conditions optimized for each one of them. Optima of pH and temperature were 5.0 and 65 °C for the three enzymes, which maintained full activity for 72 h at 50 °C and for 120 min at 60 °C (β-glucosidase) or 65 °C (β-xylosidase and xylanase). Mixed with Trichoderma reesei cellulases, C. graminicola crude extract hydrolyzed raw sugarcane trash with glucose yield of 33.1% after 48 h, demonstrating good potential to compose efficient cocktails for lignocellulosic materials hydrolysis.

Aroma characteristics of Moutai-flavour liquor produced with Bacillus licheniformis by solid-state fermentation

Abstract: UNLABELLED The potential of Bacillus licheniformis as a starter culture for aroma concentration improvement in the fermentation of Chinese Moutai-flavour liquor was elucidated. The volatile compounds produced by B. licheniformis were identified by GC-MS, in which C4 compounds, pyrazines, volatile acids, aromatic and phenolic compounds were the main ingredients. The strains B. licheniformis (MT-6 and MT-15) produced more volatile compound concentrations, mainly C4 compounds, than the type strain of B. licheniformis (ATCC 14580) at the fermentation temperature of 55°C. Meanwhile, more volatile compound concentrations were produced by B. licheniformis in solid-state fermentation than in submerged state fermentation. Thus, the strains MT-6 and MT-15 were used as the Bacillus starter culture for investigating Moutai-flavour liquor production. The distilled liquor inoculated with Bacillus starter culture was significantly different from the liquor without inoculum. This was particularly evident in the fore-run part of the distilled sample which was inoculated with Bacillus starter culture, where volatile compounds greatly increased compared to the control. Furthermore, the distilled liquor with Bacillus starter culture showed improved results in sensory appraisals. These results indicated that B. licheniformis was one of the main species influencing the aroma characteristics of Moutai-flavour liquor. SIGNIFICANCE AND IMPACT OF THE STUDY This is the first report of an investigation into the effect of Bacillus starter cultures on the flavour features of Moutai-flavour liquor, which verified that Bacillus licheniformis can enhance aroma concentration in Moutai-flavour liquor. Bacillus starter culture brought C4 compounds, pyrazines, volatile acids, aromatic and phenolic compounds to the liquor, which gave a better result in sensory appraisals.

Utilisation of By-Products from Sunflower-Based Biodiesel Production Processes for the Production of Fermentation Feedstock

Abstract: By-products streams from a sunflower-based biodiesel plant were utilised for the production of fermentation media that can be used for the production of polyhydroxyalkanoates (PHA). Sunflower meal was utilised as substrate for the production of crude enzyme consortia through solid state fermentation (SSF) with the fungal strain Aspergillus oryzae. Fermented solids were subsequently mixed with unprocessed sunflower meal aiming at the production of a nutrient-rich fermentation feedstock. The highest free amino nitrogen (FAN) and inorganic phosphorus concentrations achieved were 1.5 g L−1 and 246 mg L−1, respectively, when an initial proteolytic activity of 6.4 U mL−1 was used. The FAN concentration was increased to 2.3 g L−1 when the initial proteolytic activity was increased to 16 U mL−1. Sunflower meal hydrolysates were mixed with crude glycerol to provide fermentation media that were evaluated for the production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P(3HB-co-3HV)) using Cupriavidus necator DSM 545. The P(3HB-co-3HV) (9.9 g l−1) produced contained 3HB and 3HV units with 97 and 3 mol %, respectively. Integrating PHA production in existing 1st generation biodiesel production plants through valorisation of by-product streams could improve their sustainability.

Laccase production by Coriolopsis caperata RCK2011: Optimization under solid state fermentation by Taguchi DOE methodology

Abstract: Laccase production by Coriolopsis caperata RCK2011 under solid state fermentation was optimized following Taguchi design of experiment. An orthogonal array layout of L18 (21 × 37) was constructed using Qualitek-4 software with eight most influensive factors on laccase production. At individual level pH contributed higher influence, whereas, corn steep liquor (CSL) accounted for more than 50% of the severity index with biotin and KH2PO4 at the interactive level. The optimum conditions derived were; temperature 30°C, pH 5.0, wheat bran 5.0 g, inoculum size 0.5 ml (fungal cell mass = 0.015 g dry wt.), biotin 0.5% w/v, KH2PO4 0.013% w/v, CSL 0.1% v/v and 0.5 mM xylidine as an inducer. The validation experiments using optimized conditions confirmed an improvement in enzyme production by 58.01%. The laccase production to the level of 1623.55 Ugds−1 indicates that the fungus C. caperata RCK2011 has the commercial potential for laccase.

Solid-state fermentation: tool for bioremediation of adsorbed textile dyestuff on distillery industry waste-yeast biomass using isolated Bacillus cereus strain EBT1

Abstract: Bioremediation of textile dyestuffs under solid-state fermentation (SSF) using industrial wastes as substrate pose an economically feasible, promising, and eco-friendly alternative. The purpose of this study was to adsorb Red M5B dye, a sample of dyes mixture and a real textile effluent on distillery industry waste-yeast biomass (DIW-YB) and its further bioremediation using Bacillus cereus EBT1 under SSF. Textile dyestuffs were allowed to adsorb on DIW-YB. DIW-YB adsorbed dyestuffs were decolorized under SSF by using B. cereus. Enzyme analysis was carried out to ensure decolorization of Red M5B. Metabolites after dye degradation were analyzed using UV–Vis spectroscopy, FTIR, HPLC, and GC-MS. DIW-YB showed adsorption of Red M5B, dyes mixture and a textile wastewater sample up to 87, 70, and 81 %, respectively. DIW-YB adsorbed Red M5B was decolorized up to 98 % by B. cereus in 36 h. Whereas B. cereus could effectively reduce American Dye Manufacture Institute value from DIW-YB adsorbed mixture of textile dyes and textile wastewater up to 70 and 100 %, respectively. Induction of extracellular enzymes such as laccase and azoreductase suggests their involvement in dye degradation. Repeated utilization of DIW-YB showed consistent adsorption and ADMI removal from textile wastewater up to seven cycles. HPLC and FTIR analysis confirms the biodegradation of Red M5B. GC-MS analysis revealed the formation of new metabolites. B. cereus has potential to bioremediate adsorbed textile dyestuffs on DIW-YB. B. cereus along with DIW-YB showed enhanced decolorization performance in tray bioreactor which suggests its potential for large-scale treatment procedures.

Modern Solid State Fermentation

Abstract: Since its inception, solid-state fermentation has provided many daily necessities for human beings. However, at present, solid-state fermentation is developing slowly because of an absence of understanding of its essence and the fermentation process. Therefore, solid-state fermentation only constitutes a small part of the fermentation industry as a whole. Compared to liquid fermentation, heat transfer efficiency in solid fermentation is low, the parameters are difficult to monitor and control, and the design and amplification of bioreactors are difficult. This chapter summarizes recent research on the principles and applications of solidstate fermentation. The purposes of this chapter are not only to help readers understand the application of solid-state fermentation but also to encourage further consideration of the subject. This chapter clarifies the connotation and the status quo of solid-state fermentation and emphasizes the basic theory of biology and the principles of regulation and the transfer process. The applications and advantages of solid-state fermentation are stated. Solid-state fermentation engineering is divided into four parts: upstream, midstream, downstream and auxiliary technology; all are introduced in detail.

Production of active lipase by Rhizopus oryzae from sugarcane bagasse: solid state fermentation in a tray bioreactor

Abstract: Summary This study deals with production of lipase in solid state fermentation by Rhizopus oryzae from sugarcane bagasse. A tray bioreactor was designed for the extracellular enzyme production. Daily, lipase production was evaluated at several incubation temperatures. Furthermore, the influence of temperature and humidity of the cabinet, depth of solid bed, particle size, initial moisture content and supplementary substrate (olive oil) as carbon source was investigated. The obtained results showed that bioreactor temperature of 45 °C, humidity of 80%, solid bed depth of 0.5 cm, particle size in the range of 0.335–1 mm, substrate initial moisture content of 80% for the top tray and 70% for the middle tray and supplementary substrate of 8% (v/w) olive oil led to maximum lipase production. Under optimum fermentation conditions after 72-h incubation, maximum lipase activities for the top, middle and bottom trays were 215.16, 199.36 and 52.64 U gds−1, respectively.

Comparing submerged and solid-state fermentation of agro-industrial residues for the production and characterization of lipase by Trichoderma harzianum

Abstract: Lipase production by Trichoderma harzianum was evaluated in submerged fermentation (SF) and solid-state fermentation (SSF) using a variety of agro-industrial residues. Cultures in SF showed the highest activity (1.4 U/mL) in medium containing 0.5 % (w/v) yeast extract, 1 % (v/v) olive oil and 2.5 C:N ratio. This paper is the first to report lipase production by T. harzianum in SSF. A 1:2 mixture of castor oil cake and sugarcane bagasse supplemented with 1 % (v/w) olive oil showed the best results among the cultures in SSF (4 U/g ds). Lipolytic activity was stable in a slightly acidic to neutral pH, maintaining 50 % activity after 30 min at 50 °C. Eighty percent of the activity remained after 1 h in 25 % (v/v) methanol, ethanol, isopropanol or acetone. Activity was observed with vegetable oils (olive, soybean, corn and sunflower) and long-chain triacylglycerols (triolein), confirming the presence of a true lipase. The results of this study are promising because they demonstrate an enzyme with interesting properties for application in catalysis produced by fermentation at low cost.

Statistical optimization of culture medium for neutral protease production by Aspergillus oryzae. Comparative study between solid and submerged fermentations on tomato pomace

Abstract: A comparative study of the production of neutral protease was carried out by the cultivation of Aspergillus oryzae NRRL 2220 in solid-state fermentation (SSF) and submerged fermentation (SmF) using tomato pomace based medium. For this purpose, medium optimization was achieved using two experimental designs. The first, corresponded to the Plackett and Burman design with N = 8 experiments and k = N − 1 factors; five real (wheat bran, casein, NH4NO3, NaCl and ZnSO4) and two errors. Statistical analysis of the results allowed the selection of two factors having a significant effect on enzyme production (casein and NaCl in SSF, wheat bran and NaCl in SmF). Optima of the selected factors have been determined through a second experimental design, the central composite design of Box and Wilson with two factors; 19.79 g/L casein and 0.92 g/L NaCl for SSF and 17.92 g/L wheat bran and 1.18 g/L NaCl for SmF were found. The optimal production time of the neutral protease determined from the kinetic study was 96 h leading to 21309 U/g in SSF and 2343.5 U/g in SmF. The comparison of the proteolytic activities of the optimized media demonstrated a ratio of 9 between SSF and SmF, showing the efficiency of the solid-state fermentation compared to the submerged fermentation. The results confirmed the high biotechnological potential of this fungal strain for neutral protease production in solid-state fermentation. Additionally, the utilization of tomato pomace constitutes an efficient and inexpensive agro industrial substrate for protease production via the SSF approach and a suitable mean for its valorization and to reduce its ecological impact.

Maximization of Fructooligosaccharides and β-Fructofuranosidase Production by Aspergillus japonicus under Solid-State Fermentation Conditions

Abstract: The conditions of temperature, moisture content, and inoculum rate able to maximize the production of fructooligosaccharides (FOS) and β-fructofuranosidase (FFase) enzyme by solid-state fermentation were established. Fermentation assays were performed using the support material (coffee silverskin) moistened to 60, 70, or 80 % with a 240-g/l sucrose solution and inoculated with a spore suspension of Aspergillus japonicus to obtain 2 × 105, 2 × 106, or 2 × 107 spores/gram dry material. The fermentation runs were maintained under static conditions at 26, 30, or 34 °C during 20 h. The moisture content did not influence the FOS and FFase production; however, temperature between 26 and 30 °C and inoculum rate of approximately 2 × 107 spores/gram dry material maximized the results (FOS = 208.8 g/l with productivity of 10.44 g/l h; FFase = 64.12 units U/ml with productivity of 4.0 U/ml h). These results are considerably higher than those obtained under no optimized fermentation conditions and represent an important contribution for the establishment of a new industrial process for FOS and FFase production.

Optimization of L-asparaginase production by Serratia marcescens (NCIM 2919) under solid state fermentation using coconut oil cake

Abstract: Background: The present study focused on utilization of agrowaste byproducts generated from oil mill for L-asparaginase enzyme production using Serratia marcescens under solid state fermentation. Classical and statistical methods were employed to optimize the process variables and the results were compared. Results: The classical one factor at a time (OFAT) and response surface methodology (RSM) are employed to optimize the fermentation process. When used as the sole carbon source in SSF, coconut oil cake (COC) showed maximum enzyme production. The optimal values of substrate amount, initial moisture content, pH and temperature were found to be 6 g, 40%, 6 and 35°C respectively under classical optimization method with maximum enzyme activity of 3.87 (U gds -1 ). Maximum enzyme activity of 5.86 U gds -1 was obtained at the predicted optimal conditions of substrate amount 7.6 g of COC, initial moisture content of substrate 50%, temperature 35.5°C and pH 7.4. Validation results proved that a good relation existed between the experimental and the predicted model. Conclusions: RSM optimization approach enhances the enzyme production to 33% when compared to classical method. Utilization of coconut oil cake as a low cost substrate in SSF for L-asparaginase production makes the process economical and also reduces the environmental pollution by converting the oil mill solid waste into a useful bioproduct.

Modern Solid State Fermentation: Theory and Practice

Abstract: Introduction.- Biotechnology principles of solid-state fermentation.- Principles of solid-state fermentation engineering and its scale-up.- Aerobic solid state fermentation.- Anaerobic solid state fermentation.- Principle and Application of Solid-state Fermentation Carried Out on Inert Support Materials (Adsorbed carrier solid-state fermentation).- Development trends and application prospects of the modern solid-state fermentation.

Optimization of Ligninolytic Enzymes Production through Response Surface Methodology

Abstract: There is an increasing demand for green chemistry technologies that can cope with environmental waste management challenges. Agro-industrial residues are primarily composed of complex polysaccharides that support microbial growth for the production of industrially important enzymes such as ligninolytic enzymes. Schyzophyllum commune and Ganoderma lucidum were used alone, as well as mixed/co-culture, to produce crude ligninolytic enzymes extracts using corn stover and banana stalk as a substrate during solid state fermentation (SSF). In the initial screening, the extracted ligninolytic enzymes from S. commune produced using corn stover as the substrate showed higher activities of lignin peroxidase (1007.39 U/mL), manganese peroxidase (614.23 U/mL), and laccase (97.47 U/mL) as compared to G. lucidum and the mixed culture. To improve the production of ligninolytic enzymes by S. commune with solid state fermentation (SSF), physical factors such as pH, temperature, moisture, inoculum size, and incubation time were optimized by varying them simultaneously using response surface methodology (RSM) with a central composite design (CCD). The optimum SSF conditions were (for a 5 g corn stover substrate size): pH = 4.5; temperature = 35°C; inoculum size = 4 mL; and moisture content = 60%. Under optimum conditions, the activities of lignin peroxidase (LiP), manganese peroxidase (MnP), and laccase were 1270.40, 715.08, and 130.80 IU/mL, respectively.