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1.
The abundance of oil palm decanter cake (OPDC) is a problem in oil palm mills. However, this lignocellulosic biomass can be utilized for cellulase and polyoses production. The effectiveness of chemical and physical pretreatment in reducing the lignin content was studied by saccharification using a Celluclast 1.5 L and scanning electron microscope. Physicochemical pretreatment of OPDC with 1% (w/v) NaOH and autoclaving at 121°C for 20 min increased potential polyoses produced to 52.5% and removed 28.7% of the lignin content. The optimized conditions for cellulase production by a locally isolated fungus were a time of 120 h, a substrate of untreated OPDC, a spore concentration of 1 × 107 spore/mL, a temperature of 30°C, and a pH between 7.0 and 7.5. Trichoderma asperellum UPM1 produced carboxymethylcellulase (CMCase), ??-glucosidase and filter paper activity (FPase) in the following concentrations: 17.35, 0.53, and 0.28 U/mL, respectively. Aspergillus fumigatus UPM2 produced the CMCase, ??-glucosidase and FPase in the following amounts: 10.93, 0.76, and 0.24 U/mL. The cellulases from T. asperellum UPM1 produced 2.33 g/L of polyoses and the cellulases from A. fumigatus UPM2 produced 4.37 g/L of polyoses.  相似文献   

2.
Maximum cellulase production was sought by comparing the activities of the cellulases produced by differentTrichoderma reesei strains andAspergillus niger. Trichoderma reesei Rut-C30 showed higher cellulase activity than otherTrichoderma reesei strains andAspergillus niger that was isolated from soil. By optimizing the cultivation condition during shake flask culture, higher cellulase production could be achieved. The FP (filter paper) activity of 3.7 U/ml and CMCase (Carboxymethylcellulase) activity of 60 U/ml were obtained from shake flask culture. When it was grown in 2.5L fermentor, where pH and DO levels are controlled, the Enzyme activities were 133.35 U/ml (CMCase) and 11.67 U./ml (FP), respectively. Ammonium sulfate precipitation method was used to recover enzymes from fermentation broth. The dried cellulase powder showed 3074.9 U/g of CMCase activity and 166.7 U/g of FP activity with 83.5% CMCase recovery.  相似文献   

3.
Direct utilization of untreated oil palm trunk (OPT) for cellulases and xylanase production by Aspergillus fumigatus SK1 was conducted under solid-state fermentation (SSF). The highest activities of extracellular cellulases and xylanases were produced at 80% moisture level, initial pH 5.0, 1 × 108 spore/g (inoculum) with 125 μm of OPT as sole carbon source. The cellulases and xylanase activities obtained were 54.27, 3.36, 4.54 and 418.70 U/g substrates for endoglucanase (CMCase), exoglucanase (FPase), β-glucosidase and xylanase respectively. The crude cellulases and xylanase required acidic condition to retain their optimum activities (pH 4.0). Crude cellulases and xylanase were more stable at 40 °C compared to their optimum activities conditions (60 °C for FPase and 70 °C for CMCase, β-glucosidase and xylanase). SDS-PAGE and zymogram analysis showed that Aspergillus fumigatus SK1 could secrete cellulases (endoglucanase, exoglucanase and β-glucosidase), xylanase and protease. Enzymatic degradation of alkaline treated OPT with concentrated crude cellulases and xylanases resulted in producing polyoses.  相似文献   

4.
The production of cellulolytic enzymes by Aspergillus niger on lignocellulosic substrates groundnut fodder, wheat bran, rice bran and sawdust in solid state fermentation in a laboratory scale was compared. Czapek Dox liquid broth amended with cellulose (0.5%) was used to moisten lignocellulosic solid supports for cultivation of Aspergillus niger. The production of filter paperase, carboxymethyl cellulase and -glucosidase were monitored at daily intervals for 5 days. The peak production of the enzymes occurred within 3 days of incubation. Among solid supports used in the study, wheat bran was the best solid matrix followed by groundnut fodder in production of cellulolytic enzymes in solid state fermentation. Groundnut fodder supported significant production of FPase (2.09 FPU/g), CMCase (1.36 U/g) and -glucosidase activity (0.0117 U/g) in solid state fermentation. Considerable secretion of protein (5.10 mg/g) on groundnut fodder at peak time interval 1st day of incubation was recorded.  相似文献   

5.
The present study is aimed at simultaneous cellulase synthesis and coir pith degradation by Aspergillus nidulans using coir pith as chief substrate. The lignocellulosic biomass, coir pith is known to be an excellent carbon source for microbial cellulase production under solid state fermentation. The alkali pretreatment with sodium hydroxide was seen to enhance enzymatic hydrolysis. The effect of coir pith weight, moisture content, initial pH and growth temperature on cellulase activity and yield were investigated by response surface methodology (RSM) employing a four-factor-five-level central composite design (CCD). The results of Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD) and Scanning electron microscopy (SEM) of coir pith showed structural changes through pretreatment, in favor of enzymatic hydrolysis. Maximum carboxy methyl cellulase activity (CMCase) of 28.64 U/g and cellulase yield of 66.32% were achieved with 8 g coir pith at 70% moisture content and 40 °C temperature with pH 5 as evident from run numbers 25 and 30. Filter paper (FPase) and cellobiase (CBase) activities of 10.23 U/g and 4.31 U/g respectively were observed on the 11th day after the inoculation.  相似文献   

6.
Cellulase production using residues as substrate has been well described, as it is an interesting method of reducing the costs of processes, one of the main bottlenecks for the production of enzymes. This research describes for the first time the use of raw domestic wastewater, which is largely and continuously generated, as a culture base medium for cellulase production. The strain Trichoderma harzianum HBA03 was selected according to the highest activity produced for FPase (5.4 U/mL) and CMCase (8.2 U/mL). Peptone was selected as a nitrogen source and microcrystalline cellulose as the inducer for cellulase production, resulting in FPase activities of 5.6 and 5.0 U/mL and CMCase activities of 12.0 and 14.4 U/mL. The use of domestic wastewater as the culture medium led to an increase of 1.41 and 1.14 fold of FPase and CMCase production, respectively, compared to the synthetic medium. Production was also carried out in a bubble column reactor in which the maximum productivities achieved 10.2 U/L.h (FPase) and 64.6 U/L.h (CMCase). The presented results demonstrate the feasibility of the use of domestic wastewater for cellulases production, thereby contributing to the development of a sustainable process for reusing wastewater with a significant reduction in environmental impact.  相似文献   

7.
The optimal conditions for the production of cellulases by a marine bacterium, Psychrobacter aquimaris LBH-10, were established and their effects were compared using orthogonal array experiments based on the Taguchi method. The optimal conditions of rice bran, peptone and initial pH for the production of avicelase and CMCase by P. aquimaris LBH-10 were 50.0, 3.0, and 8.0 g/L, respectively, whereas those for filter paperase (FPase) were 100.0, 3.0, and 8.0 g/L, respectively. Rice bran was found to be the most important factor for the production of cellulases based on the calculated percentage of participation P (%) from an analysis of the variance (ANOVA). The optimal temperature for the cell growth of P. aquimaris LBH-10 was 25°C, whereas that for the production of avicelase, CMCase and FPase was 30°C. The optimal agitation speed and aeration rate for cell growth was 400 rpm and 1.5 vvm, respectively, whereas those for the production of CMCase were 300 rpm and 1.0 vvm, respectively. Aeration was found to be more important for cell growth and CMCase production than agitation. The maximum production of avicelase, CMCase and FPase in a 100 L bioreactor for 72 h under optimized conditions was 83.2, 388.7, and 75.4 U/mL, respectively.  相似文献   

8.
Enzyme extracts of cellulase [filter paper cellulase (FPase) and carboxymethyl cellulase (CMCase)], chitinase, and chitosanase produced by Aspergillus niger NRRL-567 were evaluated. The interactive effects of initial moisture and different inducers for FP cellulase and CMCase production were optimized using response surface methodology. Higher enzyme activities [FPase 79.24+/- 4.22 IU/gram fermented substrate (gfs) and CMCase 124.04+/-7.78 IU/gfs] were achieved after 48 h fermentation in solid-state medium containing apple pomace supplemented with rice husk [1% (w/w)] under optimized conditions [pH 4.5, moisture 55% (v/w), and inducers veratryl alcohol (2 mM/kg), copper sulfate (1.5 mM/kg), and lactose 2% (w/w)] (p<0.05). Koji fermentation in trays was carried out and higher enzyme activities (FPase 96.67+/-4.18 IU/gfs and CMCase 146.50+/-11.92 IU/gfs) were achieved. The nonspecific chitinase and chitosanase activities of cellulase enzyme extract were analyzed using chitin and chitosan substrates with different physicochemical characteristics, such as degree of deacetylation, molecular weight, and viscosity. Higher chitinase and chitosanase activities of 70.28+/-3.34 IU/gfs and 60.18+/-3.82 to 64.20+/-4.12 IU/gfs, respectively, were achieved. Moreover, the enzyme was stable and retained 92-94% activity even after one month. Cellulase enzyme extract obtained from A. niger with chitinolytic and chitosanolytic activities could be potentially used for making low-molecular-weight chitin and chitosan oligomers, having promising applications in biomedicine, pharmaceuticals, food, and agricultural industries, and in biocontrol formulations.  相似文献   

9.
Summary Deoxyglucose-resistant mutants of Cellulomonas biazotea secreted elevated levels of cellulases and xylanases. The production of β-glucosidase in the constitutive mutant was increased 5-fold over its parent strain. This mutant showed an approximately 1.6-fold enhanced productivity of extracellular endo-glucanase following growth on Leptochloa fusca over the mutant parent. Extracellular production of xylanase, filter-paper cellulase (FPase) and endo-glucanase (CMCase) were also altered in the mutant. Maximum volumetric productivities for xylanase, β-xylosidase, FPase, β-glucosidase and endo-glucosidase were 451, 98, 80, 95, and 143 IU l−1 h−1 which were significantly more than their respective values from the parental strains. The enzyme preparation of the mutants exhibited improved saccharification of kallar grass straw.  相似文献   

10.
绿色木霉ZY-1固态发酵产纤维素酶   总被引:1,自引:0,他引:1  
利用筛选的绿色木霉ZY-1(Trichoderma viride ZY-1)固态发酵产纤维素酶,采用稻草和麸皮为底物,考察稻草与麸皮比例随发酵时间对产酶的影响。结果表明:底物中,在m(稻草):m(麸皮)为0:5和1:4时,发酵48h,pH保持4.5左右,还原糖量急剧上升,胞外蛋白产量最低;仅以稻草作底物时,整个发酵过程中pH约为7,还原糖量最低,胞外蛋白产量较高而滤纸酶活、羧甲基纤维素酶(CMCase)和β-葡萄糖苷酶(β-Gase)酶活均较低;在m(稻草):m(麸皮)为3:2时,发酵96h,滤纸酶活达最大值5.01U/g干曲;m(稻草):m(麸皮)为1:4时,发酵96h,β-Gase酶活达最大值4.6U/g干曲;m(稻草):m(麸皮)为4:1时,发酵72h,CMCase酶活达最大值6.01U/g干曲。因此,底物中存在适量的稻草和麸皮有利于Trichoderma viride ZY—1产纤维素酶。  相似文献   

11.
Trichoderma sp. is a potential cellulase producing mesophilic fungi which grow under mild acidic condition. In this study, growth and nutritional conditions were manipulated for the maximum and cost-effective production of cellulase using lab strain Trichoderma sp. RCK65 and checked for its efficiency in hydrolysis of Prosopis juliflora (a woody substrate). Preliminary studies suggested that when 48 h old secondary fungal culture (20 % v/w) was inoculated in wheat bran moistened with mineral salt solution (pH 4.5 and 1:3 solid to moisture ratio), incubated at 30 °C and after 72 h, it produced maximum cellulase (CMCase 145 U/gds, FPase 38 U/gds and β-glucosidase 105 U/gds). However, using statistical approach a S:L ratio (1:1) was surprisingly found to be optimum that improved cellulase that is CMCase activity by 6.21 %, FPase activity by 23.68 % and β-glucosidase activity by 37.28 %. The estimated cost of crude enzyme (Rs. 5.311/1000 FPase units) seems to be economically feasible which may be due to high enzyme titre, less cultivation time and low media cost. Moreover, when the crude enzyme was used to saccharify pretreated Prosopis juliflora (a woody substrate), it resulted up to 83 % (w/w) saccharification.  相似文献   

12.
The fermentation of 1.0% untreated bagasse under optimum cultural and nutritional conditions with Aspergillus terreus GN1 indicated that the maximum rate of protein and cellulase production could be obtained during three days of submerged fermentation. Even though 16.4% protein recovery, 0.55 units CMCase/mL, and 0.027 FPase units/mL were obtained on the seventh day, the rates of increase in protein recovery and cellulase production were slower than those obtained up to these days, which were 14.3% protein recovery, 0.45 units CMCase/mL, and 0.019 units FPase/mL. There was an initial lag in the utilization of cellulose up to two days due to the utilization of the water-soluble carbohydrate present in untreated bagasse. Cellulose utilization and water-soluble carbohydrate content during fermentation were correlated with protein recovery and enzyme production. The protein and cellulase production during three days fermentation with 1.0% untreated and treated bagasse were compared and the protein content of the total biomass was calculated and treated bagasse were compared and the protein content of the biomass was calculated into constituent protein contributed by the fungal mycelium and the under graded bagasse. The total biomass recovered with untreated and treated bagasse was 1020 and 820 mg/g bagasse substrate, respectively, and contained 14.3 and 20.6% crude protein, respectively. The contribution of fungal biomass and under graded bagasse was 309 and 711, and 373 and 447 mg/g untreated and treated bagasse substrates, respectively. In an 8-L-flask trial during three days of fermentation, the recovery of SCP and cellulase were 66 g and 32,400 units (Sigma) for treated bagasse and 82 g and 8200 units (Sigma) for untreated bagasse, respectively.  相似文献   

13.

Parthenium hysterophorus biomass can be used as a non-conventional renewable feedstock for the production of bioethanol. Therefore, the present work was designed to hydrolyze P. hysterophorus biomass using cellulase enzyme produced from an actinomycete, i.e., Streptomyces sp. NAA2 using P. hysterophorus biomass as a substrate. The isolate NAA2 was identified by molecular characterization of 16SrDNA. The enzyme production by strain NAA2 was enhanced by optimization studies conducted under submerged fermentation conditions using P. hysterophorus as a substrate. The crude enzyme produced under optimized conditions was used to hydrolyze alkali-acid pretreated P. hysterophorus biomass. The highest CMCase production was achieved in 4–5 days when steam-pretreated P. hysterophorus biomass was used at 1% (w/v) concentration, using 2 discs (1 disc = 5 × 107 spores/ml) of inoculum, an initial pH 6.5, temperature at 40 °C, an agitation speed of 120–150 rpm, and by supplementing fermentation medium with 1.5% (w/v) carboxymethyl cellulose (CMC) as additional carbon source. Under optimized conditions, the actinomycete strain NAA2 showed production of 0.967 ± 0.016 U/ml CMCase, 0.116 ± 0.08 FPU/ml FPase, and 0.22 ± 0.012 U/ml β-glucosidase enzymes. On utilizing the cellulase enzyme for biomass hydrolysis, maximum 18.2% saccharification yield (of cellulose 0.202 g/g) was achieved in 96 h when enzyme and substrate levels were 30 FPU/100 ml and 2% (w/v) respectively. Parthenium hysterophorus biomass can be hydrolyzed enzymatically yielding considerable amounts of total reducing sugars. It can, therefore, be used as a feedstock for the production of bioethanol. Also, it has the potential to act as a substrate for the production of cellulases. Furthermore, the improved cellulolytic potential of Streptomyces sp. NAA2 can be exploited in various industrial applications.

  相似文献   

14.
The strain of Trichoderma reesei Rut C-30 was subjected to mutation after treatment with N-methyl-N′-nitro-N-nitrosoguanidine (NG) for 6 h followed by UV irradiation for 15 min. Successive mutants showed enhanced cellulase production, clear hydrolysis zone and rapid growth on Avicel-containing plate. Particularly, the mutant NU-6 showed approximately two-fold increases in activity of both FPA and CMCase in shake flask culture when grown on basal medium containing peptone (1%) and wheat bran (1%). The enzyme production was further optimized using eight different media. When a mixture of lactose and yeast cream was used as cellulase inducer, the mutant NU-6 yielded the highest enzyme and cell production with a FPase activity of 6.2 U ml−1, a CMCase activity of 54.2 U ml−1, a β-glucosidase activity of 0.39 U ml−1, and a fungal biomass of 12.6 mg ml−1. It deserved noting that the mutant NU-6 also secreted large amounts of xylanases (291.3 U ml−1). These results suggested that NU-6 should be an attractive producer for both cellulose and xylanase production.  相似文献   

15.
Summary The medium components for the production of extracellular cellulases by Melanocarpus sp. MTCC 3922 were optimized using solid-state fermentation. Melanocarpus sp. cultured in optimized medium containing 1.5% urea, and 0.12% KH2PO4 along with a trace element solution and surfactant (Tween 20), produced endoglucanase (142.4 U/g of substrate), Avicel-adsorbable endoglucanase (27.0 U/g of substrate), Avicelase (0.65 U/ g of substrate), FPase (39.9 U/g of substrate) and β-glucosidase (109.0 U/g of substrate) activities. The presence of sulphate ions in traces stimulated endoglucanase yields. The IEF fractionation of the crude proteins from Melanocarpus sp. showed the expression of 3, 1 and 11 isoforms of endoglucanase, β-glucosidase and xylanase, respectively.  相似文献   

16.
The activities of cellulolytic and xylanolytic enzymes produced by an anaerobic fungus (R1) which resembled Neocallimastix sp. were investigated. Carboxymethylcellulase (CMCase), cellobiase, and filter paper (FPase) activities had pH optima of 6.0, 5.5, and 6.0, respectively. CMCase and cellobiase activities both had a temperature optimum of 50 degrees C, whereas FPase had an optimum of 45 degrees C. The pH and temperature optima for xylanase activity were pH 6.0 and 50 degrees C, respectively. Growth of the fungus on wheat straw, wheat straw holocellulose, or cellulose resulted in substantial colonization, with at least 43 to 58% losses in substrate dry matter and accumulation of comparable amounts of formate. This end product was correlated to apparent loss of substrate dry weight and could be used as an indicator of fungal growth. Milling of wheat straw did not enhance the rate or extent of substrate degradation. Growth of the R1 isolate on the above substrates or xylan also resulted in accumulation of high levels of xylanase activity and lower cellulase activities. Of the cellulases, CMCase was the most active and was associated with either low or trace amounts of cellobiase and FPase activities. During growth on xylan, reducing sugars, including arabinose and xylose, rapidly accumulated in the medium. Xylose and other reducing sugars, but not arabinose, were subsequently used for growth. Reducing sugars also accumulated, but not as rapidly, when the fungus was grown on wheat straw, wheat straw holocellulose, or cellulose. Xylanase activities detected during growth of R1 on media containing glucose, xylose, or cellobiose suggested that enzyme production was constitutive.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

17.
The activities of cellulolytic and xylanolytic enzymes produced by an anaerobic fungus (R1) which resembled Neocallimastix sp. were investigated. Carboxymethylcellulase (CMCase), cellobiase, and filter paper (FPase) activities had pH optima of 6.0, 5.5, and 6.0, respectively. CMCase and cellobiase activities both had a temperature optimum of 50 degrees C, whereas FPase had an optimum of 45 degrees C. The pH and temperature optima for xylanase activity were pH 6.0 and 50 degrees C, respectively. Growth of the fungus on wheat straw, wheat straw holocellulose, or cellulose resulted in substantial colonization, with at least 43 to 58% losses in substrate dry matter and accumulation of comparable amounts of formate. This end product was correlated to apparent loss of substrate dry weight and could be used as an indicator of fungal growth. Milling of wheat straw did not enhance the rate or extent of substrate degradation. Growth of the R1 isolate on the above substrates or xylan also resulted in accumulation of high levels of xylanase activity and lower cellulase activities. Of the cellulases, CMCase was the most active and was associated with either low or trace amounts of cellobiase and FPase activities. During growth on xylan, reducing sugars, including arabinose and xylose, rapidly accumulated in the medium. Xylose and other reducing sugars, but not arabinose, were subsequently used for growth. Reducing sugars also accumulated, but not as rapidly, when the fungus was grown on wheat straw, wheat straw holocellulose, or cellulose. Xylanase activities detected during growth of R1 on media containing glucose, xylose, or cellobiose suggested that enzyme production was constitutive.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

18.
Lignocellulosic wastes can be potentially converted into several bioproducts such as glucose, xylo-oligosaccharides, and bioethanol. Certain processes, such as enzymatic hydrolysis, are generally needed to convert biomass into bioproducts. The present study investigated the production of xylanases and cellulases by Streptomyces thermocerradoensis I3 under solid-state fermentation (SSF), using wheat bran as a low-cost medium. The activities of xylanase and carboxymethyl cellulase (CMCase) were evaluated until 96 hr of incubation. The highest enzyme activity was observed after 72 hr of incubation. The crude enzyme extract was sequentially filtered, first using a 50 kDa filter, followed by a 30 kDa filter. Fraction 3 (F3) exhibited activities of both xylanase and CMCase. Xylanase and CMCase showed optimum activity at 70°C and pH 6.0 and 55°C and pH 6.0, respectively. The zymogram analysis showed a single activity band with a molecular mass of approximately 17 kDa. These findings provide strong evidence that the enzyme is a bifunctional xylanase/endoglucanase. This enzyme improved the saccharification of sugarcane bagasse by 1.76 times that of commercial cellulase. This enzyme has potential applications in various biotechnological procedures.  相似文献   

19.
王垚  徐志鸿  虞泓  党喜军 《菌物学报》2019,38(3):393-402
纤维素酶是生物燃料产业的关键酶系。本文通过刚果红染色法从腌制一年的诺邓火腿上分离到一株具有纤维素酶活性的嗜盐真菌YFCC2018SY。以形态学结合分子系统学手段对其进行鉴定,用胞外酶活测定法探索其产酶规律,并通过响应面法优化其产酶条件。结果表明该菌株属于球孢枝孢菌,且能分泌滤纸酶、内切酶和β‐葡萄糖苷酶3种嗜盐纤维素酶。响应面分析得到最优发酵条件为:NaCl含量88.58g/L、装瓶量51.21mL、起始pH 7.72。通过优化,纤维素酶活力由113.3U/mL提高到302.8U/mL,提高了167%。上述结果可以为嗜盐纤维素酶开发利用提供参考。  相似文献   

20.
Abstract

Myceliophthora thermophila encodes for large number of carbohydrate-active enzymes (CAZymes) involved in lignocellulosic biomass degradation. The mould was grown on rice straw in solid state fermentation at pH 5.0 and 45?°C that produced high levels of cellulolytic and xylanolytic enzymes i.e. 2218.12, 515.23, 478.23, 13.34?U/g DMR for xylanase, CMCase, FPase and β-glucosidase, respectively. The secretome analysis of M. thermophila BJAMDU5 by mass spectroscopy, described 124 different proteins with majority of CAZymes consisting of glycosyl hydrolases (GH), lytic polysaccharide mono-oxygenases (LPMO), carbohydrate esterases (CE) and polysaccharide lyases (PL). Furthermore, the enzyme cocktail of the mould was evaluated for hydrolysis of steam treated rice straw that produced 184.59?mg/g substrate reducing sugars after 24?h, which was used for production of bioethanol by using fast fermenting yeast Saccharomyces cerevisiae resulting in high production of bioethanol.  相似文献   

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