Michele Rigon Spier

Production and Characterization of Amylases by Aspergillus niger under Solid State Fermentation Using Agro Industrials Products

The use of agro industrials products cassava starch and sugar cane bagasse present a great potential as substrate and support, respectively, showing low production costs for amylases production under solid-state fermentation by Aspergillus niger LPB 28. The effect of various factors was examined and some variables were optimized to ?-amylase and amyloglucosidase production. Inoculum rate in different concentrations (105, 106, 107 and 108 spores/g of cassava starch) were used to inoculate the solid substrate for the SSF. The material was supplemented with nitrogen sources; calcium source and micronutrients solution. The ratios of cassava starch to sugar cane bagasse (1/1; 1.5/1; 1/1.5; 1/2; 2/1; 1/3; 3/1) were tested and the initial moisture content varying 80, 85 and 90%. Cultivation was carried out at temperatures 25, 30 and 35ºC for 48, 60 and 72 h. Study of influence of pH initial in SSF was conduced in pH 4.0, 5.0, 6.0, 7.0 and 8.0. Statistical analysis was carried out using the software STATISTICA 5.1 (StatSoft, Tulsa, OK, USA). A 32 complete factorial design (2 factors, 3 levels and 9 experiments) was used to study the effect of the factors in ?-amylase and amyloglucosidase production. The results showed cassava starch and sugar cane bagasse at the ratios of 2/1 was the best for optimum production of ?-amylase and amyloglucosidase. The maximum yield (?-amylase 1732.95 U/g of cassava starch and amyloglucosidase 2044.94 U/g of cassava starch) was achieved with optimized process parameters such as incubation period (60 hours), moisture level was 90%, inoculation rate (105 spores/g of dried material), pH 4.0 and fermentation temperature (30ºC). The nitrogen source (KNO3) also enhanced the ?-amylase and amyloglucosidase activities. In kinetic characterization of enzymes the Michaelis-Menten constant KM and maximum velocity Vmax (KM 10.84 g/l, Vmax 3.42 g/l) for ?-amylase and KM 11.32 g/l and Vmax 5.18 g/l for amyloglucosidase.

Analysis of inducers of xylanase and cellulase activities production by Ganoderma applanatum LPB MR-56

This manuscript describes the analysis of the effect of cellulose, carboxymethylcellulose (CMC), xylan, and xylose as inducers of cellulase and xylanase activity production by Ganoderma applanatum MR-56 and the optimization of their production in liquid cultures by statistical methods. The Plackett-Burman screening design was applied to identify the most significant inducers of xylanase and cellulase activities production by G. applanatum MR-56. The most significant effect on xylanase and cellulase activities production was exercised by cellulose, even if xylose and CMC were also effective at some times. The combined effect of cellulose, yeast extract, and pH was analyzed by a 2(3) factorial experimental design with four central points that showed that the maximum tested cellulose (1 % w/v) and yeast extract (5 g L(-1)) concentrations gave the maximum production of xylanase (8.24 U mL(-1)) and cellulase (3.29 U mL(-1)) activity at pH 6 and 4, respectively. These values achieved for cellulase and xylanase activity represent 12-25 fold and 36 fold higher values than the maximum so far reported for other strains of G. applanatum, respectively.

INCREASE IN PHYTASE SYNTHESIS DURING CITRIC PULP FERMENTATION

Citric pulp bran was used for the first time as substrate for phytase synthesis under solid-state fermentation. An A. niger FS3 phytase strain was applied in optimization studies. A Plackett-Burman screening design identified significant physicochemical variables. These preselected variables were subsequently optimized using a central composite rotational design (CCRD). The maximum phytase production was achieved with the following optimum variables: 30°C temperature, 65% initial moisture content, 0.3 M Na-citrate buffer concentration, initial pH 5.0, and 1.5% urea concentration. An overall 4.3-fold improvement in phytase production was successfully achieved.

Lichtheimia blakesleeana as a new potencial producer of phytase and xylanase.

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 23 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.

Monitoring fermentation parameters during phytase production in column-type bioreactor using a new data acquisition system

Fermentation parameters for phytase production in column-type bioreactor were monitored using a new data acquisition system. There are a number of studies reporting phytase production in flasks, but a lack of data about microorganism respiration behaviour during phytase production using column bioreactor. The objectives of this work were the monitoration of fermentation parameters during phytase production and its relation with fungal growth and forced air. Phytase production by A. niger FS3 increased with forced air. The O2 consumption and CO2 production during solid-state fermentation were monitored by sensors (in the bottom and top of the columns) linked to controllers, recorded by acquisition software and processed by Fersol2® software tool. Phytase synthesis was associated with fungal growth. Therefore, phytase could be used to estimate FS3 biomass formed in citric pulp degradation.

A simplified model for A. Niger FS3 growth during phytase formation in solid State fermentation

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 (YX/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.

Current Market Trends and Future Directions

Probiotic products have been used worldwide and they are increasingly gaining popularity. Current trends in the consumption of probiotics are associated with increased levels of health-consciousness, and the availability of probiotics in the form of dietary supplements. Several companies have profited by marketing these products in different forms, with different purposes, and with recommendation for all ages. Important aspects in maintaining the viability and bioactivity of probiotic strains during processing and storage are also discussed in this chapter. The probiotic consumption by infants and the elderly has been supported by scientific evidences and represents a potential niche markets that are in developing and has led to the growth segment of probiotic products.

The Pretreatment Step in Lignocellulosic Biomass Conversion: Current Systems and New Biological Systems

The demand for liquid fuels is constantly increasing, and ethanol from lignocellulosic biomass might be one of the most important solutions for this problem. Although biomass may be cheap, the costs of processing it can be high. Many technologies for converting biomass into bioethanol have been developed, which include the pretreatment of biomass, enzymatic saccharification of the pretreated biomass, and fermentation of the hexose and pentose sugars released by hydrolysis, and saccharification. In this chapter, the most frequently used and new biological pretreatment methods of lignocellulosic biomass are discussed. The common initial pretreatment steps of a lignocellulosic material such as drying, grinding, and granulometric classification are presented, and then the thermo-chemical and biological treatments including biopulping and enzymatic pretreatment are also discussed.

Aqueous two-phase extraction for partial purification of Schizophyllum commune phytase produced under solid-state fermentation

Abstract This study describes a simple strategy for partial protein purification using an aqueous two- phase system (ATPS) of polyethyleneglycol (PEG)/sodium citrate. The protein studied was phytase produced by Schizophyllum commune under solid-state fermentation (SSF). A 24 experimental design (20 runs and 4 central points) was carried out with four factors (PEG molar mass, citrate concentration, PEG concentration, and pH) to evaluate the enzyme extraction. The responses’ partition coefficient (K), yield (Y), and the purification factor (PF) were analysed. The best system obtained was with 14% (w/w) sodium citrate, 22% (w/w) PEG with a molar mass of 1500 (g/mol), and pH of 7. The maximum partition coefficient (K) was 2.63 and also the citrate concentration had a positive effect. Under these conditions, in the top phase the highest phytase yield achieved was 367%, and the purification factor (PEG) was 5.43. Liquid–liquid extraction can therefore be used as a first step in the purification processes of phytase from S. commune.

Formulated products containing a new phytase from Schyzophyllum sp. phytase for application in feed and food processing

A new formulated product containing high yield of p hytase from Schizophyllum sp., an important mushroom used for medicinal studies, was developed for applicatio n in feed industries and for future use in food pro cessing. The enzyme presented a high activity yield 55.5 U/mL an d 6240 U/gds in liquid and solid formulated product , respectively. It showed a good shelf-life in concen trated product, retaining 67.8% of its activity aft er 60 days of storage at room temperature and 90% of the activity was maintained in the liquid formulation after the same period. Powder bioformulated product maintained 77% of its activity after two months of storage, without the a ddition of chemical additives, which was named as a new biofor mulated product containing high quantities of phyta se. After separation and concentration steps, enzyme stabilit y was monitored in two forms: liquid and solid. The liquid product was stable with the presence of manitol and polyethylene glycol at 1% (w/v), while solid produ ct was the most stable product without the presence of chemica l additives.