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1.
Solid-state fermentation of coconut oil cake has been carried out with Rhizopus oligosporus for the production of phytase. Phytase is used commercially in the animal feed industry to improve animal performance because there is a substantial and growing interest among swine and poultry producers in the application of phytase to improve the nutritional quality in animal feeds. Demonstrated benefits include improved feed yield ratios and reduction in the environmental costs associated with the disposal of animal wastes. We report the production of extracellular phytase by R. oligosporus under solid-state fermentation using coconut oil cake as substrate. Maximal enzyme production (14.29 U/g of dry substrate) occurred at pH 5.3, 30°C, and 54.5% moisture content after 96 h of incubation. The addition of extra nutrients to the substrate resulted in inhibition of product formation. The results indicate the scope for production of phytase using coconut oil cake as solid substrate without additional nutrients.  相似文献   

2.
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.  相似文献   

3.
There is an increasing interest for the organic residues from various sectors of agriculture and industries over the past few decades. Their application in the field of fermentation technology has resulted in the production of bulk chemicals and value-added products such as amino acid, enzymes, mushroom, organic acids, single-cell protein, biologically active secondary metabolites, etc. (Ramachandran et al., Bioresource Technology 98:2000–2009, 2007). In this work, the production of extracellular xylanase by the fungus Penicillium canescens was investigated in solid-state fermentation using five agro-industrial substrates (soya oil cake, soya meal, wheat bran, whole wheat bran, and pulp beet). The best substrate was the soya oil cake. In order to optimize the production, the most effective cultivation conditions were investigated in Erlenmeyer flasks and in plastic bags with 5 and 100 g of soya oil cake, respectively. The initial moisture content, initial pH, and temperature of the culture affected the xylanase synthesis. The optimal fermentation medium was composed by soya oil cake crushed to 5 mm supplemented with 3% and 4% (w/w) of casein peptone and Na2HPO4.2H2O. After 7 days of incubation at 30 °C and under 80% of initial moisture, a xylanase production level of 18,895 ± 778 U/g (Erlenmeyer flasks) and 9,300 ± 589 U/g (plastic bags) was reached. The partially purified enzyme recovered by ammonium sulfate fractionation was completely stable at freezing and refrigeration temperatures up to 6 months and reasonably stable at room temperature for more than 3 months.  相似文献   

4.
This study demonstrates the production of a generic nutrient-rich feedstock using by-product streams from palm oil production that could be used as a substitute for commercial fermentation supplements. Solid-state fermentations of palm kernel cake (PKC) and palm-pressed fiber (PPF) were conducted in tray bioreactors and a rotating drum bioreactor by the fungal strain Aspergillus oryzae for the production of crude enzymes. The production of protease was optimized (319.3 U/g) at an initial moisture content of 55 %, when PKC was used as the sole substrate. The highest free amino nitrogen (FAN) production (5.6 mg/g) obtained via PKC hydrolysis using the crude enzymes produced via solid-state fermentation was achieved at 50 °C. Three initial PKC concentrations (48.7, 73.7, and 98.7 g/L) were tested in hydrolysis experiments, leading to total Kjeldahl nitrogen to FAN conversion yields up to 27.9 %. Sequential solid-state fermentation followed by hydrolysis was carried out in the same rotating drum bioreactor, leading to the production of 136.7 U/g of protease activity during fermentation and 196.5 mg/L of FAN during hydrolysis. Microbial oil production was successfully achieved with the oleaginous yeast strain Lipomyces starkeyi DSM 70296 cultivated on the produced PKC hydrolysate mixed with commercial carbon sources, including glucose, xylose, mannose, galactose, and arabinose.  相似文献   

5.
The yeast Ogataea thermomethanolica has recently emerged as a potential host for heterologous protein expression at elevated temperature. To evaluate the feasibility of O. thermomethanolica as heterologous host in large-scale fermentation, constitutive production of fungal phytase was investigated in fed-batch fermentation. The effect of different temperatures, substrate feeding strategies, and carbon sources on phytase production was investigated. It was found that O. thermomethanolica can grow in the temperature up to 40 °C and optimal at 34 °C. However, the maximum phytase production was observed at 30 °C and slightly decreased at 34 °C. The DOT stat control was the most efficient feeding strategy to obtain high cell density and avoid by-product formation. The table sugar can be used as an alternative substrate for phytase production in O. thermomethanolica. The highest phytase activity (134 U/mL) was obtained from table sugar at 34 °C which was 20-fold higher than batch culture (5.7 U/mL). At a higher cultivation temperature of 38 °C, table sugar can be used as a low-cost substrate for the production of phytase which was expressed with an acceptable yield (85 U/mL). Lastly, the results from this study reveal the industrial favorable benefits of employing O. thermomethanolica as a host for heterologous protein production.  相似文献   

6.
Aspergillus oryzae SBS50 secreted a high titre of phytase in solid-state fermentation (SSF) using wheat bran at 30 °C after 96 h at the initial substrate to moisture ratio of 1:2 and a water activity of 0.95. The production of phytase increased when wheat bran was supplemented with sucrose and beef extract. Further enhancement in enzyme production was recorded when the substrate was supplemented with the surfactant Triton X-100 (145 U/g of DMB). An overall 29-fold improvement in phytase production was achieved owing to optimization. Under optimized conditions, the mould secreted 9.3-fold higher phytase in SSF as compared to submerged fermentation (SmF). The mesophilic mould also secreted amylase, cellulase (CMCase), pectinase and xylanase along with phytase in SSF. Scanning electron microscopy revealed luxuriant growth of A. oryzae on wheat bran with abundant spores. The enzyme dephytinized wheat bran with concomitant liberation of inorganic phosphate.  相似文献   

7.
The production of lipase by Penicillium simplicissimum in solid-state fermentation was studied using babassu cake as the basal medium. Tray-type and packed-bed bioreactors were employed. In the former, the influence of temperature; content of the medium, and medium supplementation with olive oil, sugarcane molasses, corn steep liquor, and yeast hydrolysate was studied. For all combinations of supplements, a temperature of 30°C, a moisture content of 70%, and a concentration of carbon source of 6.25% (m/m, dry basis) provided optimum conditions for lipase production. When used as single supplements olive oil and molasses also were able to provide high lipase activities (20 U/g). Using packed-bed bioreactors and molasses-supplemented medium, optimum conditions for enzyme production were air superficial velocities above 55 cm/min and temperatures below 28°C. The lower temperature optimum found for these reactors is probably related to radial heat gradient formation inside the packed bed. Maximum lipase activities obtained in these bioreactors (26.4 U/g) were 30% higher than in tray-type reactors.  相似文献   

8.
The β-carbolines in our diet, mainly including harman and norharman, are a group of biologically active, naturally occurring plant-derived alkaloids. Fragrant sesame seed oil is one of the most popular flavor edible oils in China. Considering that sesame seeds are roasted at 200–240 °C during the processing of flavor sesame seed oils, it is meaningful to investigate the levels of β-carboline compounds in various sesame seed oils. In this work, the levels of β-carbolines (harman and norharman) in different types of sesame seed oils in China (e.g., pressed fragrant sesame oil, ground fragrant sesame oil) have been determined systematically. The results showed that the levels of total β-carbolines in pressed fragrant sesame oils (700.5~2423.2 μg/kg) were higher than that in ground fragrant sesame oils (660.4~1171.7 μg/kg). Roasting sesame seeds at high temperatures (200–240 °C) led to higher levels of β-carbolines (660~2400 μg/kg) in fragrant sesame seed oils. In addition, the loss of tryptophan might be attributed to the formation of β-carbolines in sesame seeds during the roasting process. In general, fragrant sesame seed oils (pressed fragrant sesame oils, ground fragrant sesame oils) contain higher levels of β-carbolines due to the formation of harman and norharman during the roasting sesame seed process.  相似文献   

9.
Xylanase is produced by Penicillium canescens 10–10c from soya oil cake in static conditions using solid-state fermentation. The impact of several parameters such as the nature and the size of inoculum, bed-loading, and aeration is evaluated during the fermentation process. Mycelial inoculum gives more production than conidial inoculum. Increasing the quantity of inoculum enhances slightly xylanase production. Forced aeration induces more sporulation of strain and reduces xylanase production. However, forced moistened air improves the production compared to production obtained with forced dry air. In addition, increasing bed-loading reduces the specific xylanase production likely due to the incapacity of the Penicillium strain to grow deeply in the fermented soya oil cake mass. Thus, the best cultivation conditions involve mycelial inoculum form, a bed loading of 1-cm height and passive aeration. The maximum xylanase activity is obtained after 7 days of fermentation and attains 10,200 U/g of soya oil cake. These levels are higher than those presented in the literature and, therefore, show all the potentialities of this stock and this technique for the production of xylanase.  相似文献   

10.
One relevant limitation hindering the industrial application of microbial lipases has been attributed to their production cost, which is determined by the production yield, enzyme stability among other. The objective of this work was to evaluate the concentration and immobilization of lipase extracts from Penicillium brevicompactum obtained by solid-state fermentation of babassu cake and castor bean cake. The precipitation with ammonium sulfate 60% of saturation of crude extract obtained with babassu cake as raw material showed an enhancement in hydrolytic and esterification activities from 31.82 to 227.57 U/g and from 170.92 to 207.40 U/g, respectively. Concentrated lipase extracts showed preference to medium-chain triglycerides and fatty acids. It is shown that the enzyme activity is maintained during storage at low temperatures (4 and −10°C) for up to 30 days. Higher esterification activities were achieved when the lipase extract was immobilized in sodium alginate and activated coal.  相似文献   

11.
The marine yeast strain Kodamea ohmeri BG3 isolated from the gut of a marine fish (Hexagrammes otakii) was found to secrete a large amount of phytase into the medium. The crude phytase produced by this marine yeast showed the highest activity at pH 5.0 and 65 °C. The optimal medium for phytase production contained oat 10.0 g/l, ammonium sulfate 15.0 g/l, glucose 30 g/l, and NaCl 20.0 g/l, while the optimal cultivation conditions for phytase production were pH 5.0, a temperature of 28 °C, and a shaking speed of 170 rpm. Under the optimal conditions, over 557.9 mU/ml of phytase activity was produced within 72 h of fermentation at the shake flask level. This is a very high level of phytase activity produced by yeasts. We think that the medium and process for phytase production by the marine yeast strain were very simple, and such marine yeast from the gut of natural marine fish may have a potential application in the maricultural industry and marine environmental protection. The results demonstrate that phytate was actively degraded by the crude phytase within a short period.  相似文献   

12.
Phytases act on phytic acid, an antinutrient factor present in animal feeds, and release inorganic phosphate. We optimized the production parameters for phytase production using Thermoascus aurantiacus (TUB F 43), a thermophilic fungal culture, by submerged fermentation. A semisynthetic medium containing glucose, starch, peptone, and minerals supplemented with 3.75% (w/v) wheat bran particles was found to be the best production medium among the various combinations tried. Further supplementation of this medium with surfactants such as Tween-20 and Tween-80 considerably enhanced the enzyme yield. A maximum phytase activity (468.22 U/mL) was obtained using this production medium containing 2% (v/v) Tween-20 after 72 h of fermentation at 45°C in shake-flask cultures with a rotation of 150 rpm. Herein we present details of a few of the process parameter optimizations. The phytase enzyme was found to be thermostable, and the optimal temperature for phytase activity was found to be 55°C. However, 80% of the activity still remained when the temperature was shifted to 70°C.  相似文献   

13.
Hong  Kui  Ma  Yan  Li  Meiqui 《Applied biochemistry and biotechnology》2001,91(1-9):777-785
Phytases produced by numerous microorganisms and plants degrade phytic acid that has chelated with metal ions in food and feed. It is important to study phytase for the role of metal ions in nutrition of animals and humans as wellas in the reduction of organic phosphate content of a queous environment. This article reports on solid-state fermentation of phytase from a new substrate of cassava dregs. Large quantities of cassava dregs are produced in tropical areas as a by product of cassava starch processing. Protein and inorganic salts were found to be low in cassava dregs. Cassava dregs could be employed for phytase synthesis after the addition of a nitrogen source and mineral salts. Ammonium nitrate was the best nitrogen source among the nitrogen sources investigated, including beef extract, yeast extract, urea, ammonium nitrate, sodium nitrate, and ammonium sulfate. Sodium dodecyl sulfate promoted phytase production from cassava dregs. A maximum phytase yield of 6.73 U/g of dry mass was obtained. The obtained phytase was stable at feed-processing temperature, since 70% of initial enzyme activity was maintained after 30 min of treatment at 75°C.  相似文献   

14.
In Asian countries, sesame seed oil unsaponified matter is used as a natural food additive due to its associated antioxidant effects. We determined and purified the primary lignans sesamin and sesamolin in sesame seed oil unsaponified matter using reversed‐phase liquid chromatography coupled with photodiode array and tandem mass spectrometry and high‐speed countercurrent chromatography. Calibration curves showed good correlation coefficients (r2 > 0.999, range 0.08 and/or 0.15 to 5 μg/mL) with a limit of detection (at 290 nm) of 0.02 μg/mL for sesamin and 0.04 μg/mL for sesamolin. Sesame seed oil unsaponified matter contained 2.82% sesamin and 2.54% sesamolin, respectively. Direct qualitative analysis of sesamin and sesamolin was achieved using quadrupole mass spectrometry with positive‐mode electrospray ionization. Pure (>99%) sesamin and sesamolin standards were obtained using high‐speed countercurrent chromatographic purification (hexane/ethyl acetate/methanol/water; 7:3:7:3). An effective method for determining and purifying sesamin and sesamolin from sesame seed oil unsaponified matter was developed by combining these separation techniques for standardized food additives.  相似文献   

15.
Lipase, protease, and amylase production by Penicillium restrictum in solid-state fermentation was investigated. The basal medium was an industrial waste of babassu oil (Orbignya oleifera) production. It was enriched with peptone, oliveoil, and Tween-80. The supplementation positively influenced both enzyme production and fungal growth. Media enriched with Tween-80 provided the highest protease activity (8.6 U/g), whereas those enriched with peptone and olive oil led to the highest lipase (27.8 U/g) and amylase (31.8 U/g) activities, respectively.  相似文献   

16.
The aim of the study was to determine the optimal conditions, that is, the content of sesame oil and the amount of carboxymethylcellulose, to obtain stable dispersion systems. Emulsions were stored under different temperature conditions. For this purpose, six emulsions were prepared and their stability was examined empirically using techniques including particle size analysis, optical microscopy, and the Turbiscan test. The emulsion containing 40 g of oil and 0.6 g of thickener had the highest stability. No destabilizations in whole the range of stored temperature were observed for the emulsion with that composition. Emulsion was stable as well at cool temperature as at extreme environment (40°C). Nowadays, the use of O/W emulsions based on vegetable oil is continuously increasing. To date, sesame oil has been used mainly for direct consumption. The present work indicates a novel possibility for use of sesame oil as the fat base of an emulsion system. Besides, the study gave information about parameters of long-term stability emulsion what is the key in the quality of the dispersion systems. This knowledge is necessary for the industry in order to avoid destabilizing processes occurring in a new product.  相似文献   

17.
Summary Neutron activation analysis has been used to study uranium incorporation in poultry bones as function of chow doped with: (a) uranium (20 ppm); (b) U-doped food (20 ppm) plus phytase (120 ppm) and (c) U-doped food (20 ppm) plus phytase (180 ppm). To investigate this situation experiments involving several groups of Cobb broilers was performed. Two animals per group were sacrificed weekly up to their adultness and uranium concentration in the tibia was measured. It was observed that the concentration of uranium (µg U/g bone) is decreasing all along the animal life spanning period of 14-42 days. This behavior suggests that the skeleton mass is growing faster than the corresponding accumulation of uranium. The administration of phytase seems not to alter this scenario.  相似文献   

18.
The production of lipases by Penicillium simplicissimum using solid-state fermentation and soy cake as substrate was investigated. The effects of temperature, cake moisture, and carbon supplementation on lipase production were studied using a two-level experimental plan. Moisture, pH, and lipase activity were followed during fermentation. Statistical analysis of the results was performed to evaluate the effect of the studied variables on the maximum lipase activity. Incubation temperature was the variable that most affected enzyme activity, showing a negative effect. Moisture and carbon supplementation presented a positive effect on activity. It was possible to obtain lipase activity as high as 21 U/g of dry cake in the studied range of process variables.  相似文献   

19.
Probiotics with ability to produce conjugated linoleic acid (CLA) is considered as an additive health benefit property for its known role in colon cancer mitigation. The conversion involves the biohydrogenation of the unsaturated fatty acid into conjugated form. Probiotic strain Pediococcus spp. GS4 was efficiently able to biohydrogenate linoleic acid (LA) into its conjugated form within 48 h of incubation. Quantum of CLA produced with a concentration of 121 μg/ml and sustained cell viability of 8.94 log cfu/ml maximally. Moreover, antibacterial effect of LA on the strain ability for biohydrogenation was examined at different concentrations and concluded to have a direct relationship between LA and amount of CLA produced. The efficiency of the strain for CLA production at different pH was also estimated and found maximum at pH?6.0 with 149 μg/ml while this ability was reduced at pH?9.0 to 63 μg/ml. Sesame oil, which is rich in the triacylglycerol form of LA, was also found to act as a substrate for CLA production by Pediococcus spp. GS4 with the aid of lipase-catalyzed triacylglycerol hydrolysis and amount of CLA produced was 31 μg/ml at 0.2 % while 150 μg/ml at 1.0 % of lipolysed oil in skim milk medium. Conjugated form was analyzed using UV scanning, RP-HPLC, and GC-MS. This study also focused on the alternative use of lipolysed sesame oil instead of costly LA for biohydrogenation and could be a potential source for the industrial production of CLA.  相似文献   

20.
A Gram-positive coccus-shaped bacterium capable of synthesizing higher relative molecular weight (M r), polyhydroxybutyrate (PHB) was isolated from sesame oil and identified as Staphylococcus epidermidis (by Microbial ID, Inc., Newark, NJ). The experiment was conducted by shake flask fermentation culture using media containing fructose. Cell growth up to a dry mass of 2.5 g/L and PHB accumulation up to 15.02% of cell dry wt was observed. Apart from using single carbohydrate as a sole carbon source, various industrial food wastes including sesame oil, ice cream, malt, and soya wastes were investigated as nutrients for S. epidermidis to reduce the cost of the carbon source. As a result, we found that by using malt wastes as nutrient for cell growth, PHB accumulation of S. epidermidis was much better than using other wastes as nutrient source. The final dried cell mass and PHB production using malt wastes were 1.76 g/L and 6.93% polymer/cells (grams/gram), and 3.5 g/L and 3.31% polymer/cells (grams/gram) in shake flask culture and in fermentor culture, respectively. The bacterial polymer was characterized by 1H-nuclear magnetic resonance (NMR), 13C-NMR, Fourier transform infrared, and differential scanning calorimetry. The results show that with different industrial food wastes as carbon and energy sources, the same biopolymer (PHB) was obtained. However, the use of sesame oil as the carbon source resulted in the accumulation of PHB with a higher melting point than that produced from other food wastes as carbon sources by this organism under similar experimental conditions.  相似文献   

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