绿色木霉在稻壳和麸皮混合基质上固态发酵生产纤维素酶的研究

以稻壳和麸皮的混合物为主要原料 ,采用绿色木霉 (Trichodermasp 3 2 942 )固态发酵生产纤维素酶。浅盘发酵实验表明 ,稻壳经 4%的NaOH溶液 40℃浸泡 2 4h后 ,以 30 %的质量比添加到麸皮中发酵 ,滤纸酶活和CMC酶活比未经处理时提高了 2 7 5 %和 2 5 1 %;最优发酵条件为 :培养温度 30℃ ,接种量 2 0 %,培养基初始含水量 45 %～ 60 %,此时滤纸酶活和CMC酶活可达 5 1 5IU/g(干物质 )和 38 46IU/g(干物质 )。     

Enhanced Oil Recovery by Pre-treatment of Mustard Seeds Using Crude Enzyme Extract Obtained from Mixed-Culture Solid-State Fermentation of Kinnow (Citrus reticulata) Waste and Wheat Bran

Solid-state fermentation (SSF) of kinnow (Citrus reticulata) waste supplemented with wheat bran was used for production of cellulase, protease and pectinase with individual and mixed cultures of Trichoderma reesei and Aspergillus niger. Mustard seeds were pre-treated with crude filtrate extract (CFE) obtained from A. niger and T. reesei independently, and combination of the two cultures, prior to solvent extraction. Mixed-culture fermentation resulted in higher enzyme activity for filter paper cellulase (FPU), carboxymethyl cellulase (CMCase), β-glucosidase, and exoploygalacturonase (exo-PG) in comparison to fermentation with individual cultures. This study indicated that pre-treatment using crude enzyme obtained with mixed cultures enhanced the oil recovery by 11% as compared to control where no enzyme was used. Mustard seeds pre-treated with CFE obtained from mixed cultures having ratio of 2:1:1 for exo-polygalacturonase, FPU, and protease resulted in highest oil recovery. About 7–10% more oil was recovered when mustard seeds were pre-treated with CFE obtained from individual cultures, compared with control. Enzymatic pre-treatment also improved some of the quality attributes of mustard oil. To the best of our knowledge, this is the first study where mixed-culture SSF was attempted to produce enzyme consortium for pre-treatment of mustard seeds for enhanced oil recovery.     

丙酮丁醇梭菌发酵小麦麸皮生产丁醇

对丙酮丁醇梭菌(Clostridium acetobutylicum)8016发酵小麦麸皮或麸皮混合其他非粮淀粉质原料生产丁醇进行了研究。实验结果表明,当初始糖浓度为55g/L时,以纯麸皮为底物,发酵终点总溶剂达到21.43g/L,丁醇13.08g/L,糖醇转化率39.57%;以麸皮混合红薯、木薯为底物,发酵终点总溶剂达到22.37g/L,丁醇13.24g/L,糖醇转化率为39.95%,均能达到传统玉米醪发酵丁醇水平。证明小麦麸皮作为一种粮食加工废弃物完全可以替代粮食用于丙酮丁醇发酵。     

采用黑曲霉发酵制备阿拉伯木聚糖酶和阿魏酸酯酶的研究

采用黑曲霉发酵麦麸、蔗渣和玉米麸皮都能获得阿魏酸酯酶和阿拉伯木聚糖酶,并在第3d达到产酶高峰。但不同发酵基质产酶活性差别很大,麦麸最好,蔗渣最差。同时,酶制剂因发酵基质不同会产生底物专一性,因此,在生产酶制剂时应注意根据所降解的对象选择发酵基质。     

Effect of Moisture on Trichoderma Conidia Production on Corn and Wheat Bran by Solid State Fermentation

In the present work, the use of low-cost substrates to produce Trichoderma spores was evaluated. Rice, corn bran, and wheat bran were used as solid substrate to grow Trichoderma harzanium sp., Trichoderma viride sp., Trichoderma koningii sp., and Trichoderma polysporum sp. No external nutrient sources were added to the solid substrate that was only moisturized with deonized water, sterilized, inoculated, and cultivated at 30 °C for 7 days. Wheat bran showed to be the most suitable substrate to produce Trichoderma spores for all strains that were evaluated. High spore counts were obtained for T. harzianum sp. (28.30 × 10⁸/gds) and T. viride sp. (24.10 × 10⁸ spores/gds).     

响应面法优化麦麸发酵产植酸酶条件的研究

以纳豆芽孢杆菌JSU-2为供试菌株,麦麸皮为唯一固体发酵基质,运用响应面法对其产植酸酶的条件进行优化.首先用24-1部分因子试验设计对影响植酸酶活性的主要变量进行了评价,发现主要影响因子为麸皮与水的比例和培养时间.然后用中心组合试验设计确定主要变量的最佳水平.最佳产酶发酵条件为:粒径为3 mm、麸皮与水的比例为1:9.6、接种量为3 mL和培养时间为25 h.在最佳产酶条件下进行发酵,得到的植酸酶活性为595 U/g麦麸.     

New isolate of Trichoderma viride strain for enhanced cellulolytic enzyme complex production

A new Trichoderma viride stain was isolated from Singapore soil samples. Its mutants were developed by using ethyl methyl sulfonate (EMS) treatment and UV-irradiation followed by a semi-quantitative plate clearing assay on phosphoric-acid-swollen cellulose plates. Mutant EU2-77 proved to be the most promising extracellular cellulase producer among 20 mutants in a screening program performed in shake flask fermentation after plate screening. Soluble protein content, filter paper cellulase (FPase) activity, β-glucosidase activity and endoglucanase (CMCase) activity of the fermentation broths of the mutant strain were increased to 1.67, 2.49, 2.16, and 2.61 folds, respectively, compared with the wild strain. This enzyme complex produced by mutant EU2-77 contained FPase (2.19 IU/ml), CMCase (16.46 IU/ml), β-glucosidase (4.04 IU/ml), xylanase (42.37 IU/ml), and β-xylosidase (0.12 IU/ml). The soluble protein concentration in the enzyme complex was 1.69 mg/ml. The hydrolytic capacities of fermentation supernatants of T. reesei Rut-C30, the wild strain T. viride NP13a and mutant T. viride EU2-77 were compared with the commercial enzymes on the hydrolysis of waste newspaper. The crude enzymes prepared by T. viride EU2-77 showed much higher hydrolysis performance than that from the commercial strain Rut-C30 and demonstrated much comparable hydrolytic performances with the commercial enzyme mixtures. T. viride mutant EU2-77 produced high levels of extracellular cellulases as well as β-glucosidase, rendering the supplementation of β-glucosidase unnecessary in waste newspaper hydrolysis.     

Production of Cell Membrane-Bound α- and β-Glucosidase by Lactobacillus acidophilus

Hydrolytic enzymes, viz. α- and β-glucosidase, were produced from indigenous isolate, Lactobacillus acidophilus, isolated from fermented Eleusine coracana. Production of these enzymes was enhanced by optimizing media using one factor at a time followed by response surface methodology. The optimized media resulted in a 2.5- and 2.1-fold increase in α- and β-glucosidase production compared with their production in basal MRS medium. Localization studies indicated 80% of the total activity to be present in the cell membrane-bound fraction. Lack of sufficient release of these enzymes using various physical, chemical, and enzymatic methods confirmed their unique characteristic of being tightly cell membrane bound. Enzyme characterization revealed that both α- and β-glucosidase exhibited optimum catalytic activity at 50 °C and pH 6.0 and 5.0, respectively. K _m and V _max of α-glucosidase were 4.31 mM and 149 μmol min⁻¹ mL⁻¹ for p-nitrophenyl-α-d-glucopyranoside as substrate and 3.8 mM and 120 μmol min⁻¹ mL⁻¹ for β-glucosidase using p-nitrophenyl-β-d-glucopyranoside as the substrate.     

Improving Solid-State Fermentation of Monascus purpureus on Agricultural Products for Pigment Production

In the present study, the effects of culture medium and temperature on red pigment production and mycelia growth were evaluated. The maximum red pigment production was found when Monascus purpureus CMU001 was cultivated on potato dextrose broth at 30 °C for 2 weeks. The highest amount of dry weight was achieved when cultivated on tryptone glucose yeast extract medium. Cheap agricultural products and residues were used as substrates for pigment production. Corn meal was the best substrate for pigment production (19.4 U/gds) when compared to peanut meal, coconut residue, and soybean meal. The highest pigment yield (129.63 U/gds) was found when corn meal was supplemented with 8% (w/w) glucose, followed by coconut residue (63.50 U/gds), peanut meal (52.50 U/gds), and soybean meal (22.50 U/gds). Galactose, sorbose, psicose, and mannitol were found to be good supplements next to glucose but not xylitol. Pigment was not stable at high temperature and long exposure to UV. The intensity of red pigment decayed 30.57% and 5.41% after autoclaving and pasteurization, respectively.     

绿色木霉JD-1固态发酵玉米芯产纤维素酶条件优化

以玉米芯与麸皮为主要原料,对影响绿色木霉（Trichoderma viride）JD-1固态发酵的因素如玉米芯与麸皮的比例、氮源浓度、发酵温度、时间、料水比等进行研究。在单因素试验的基础上,采取正交试验设计进行优化。结果表明,最佳固体发酵条件为即玉米芯与麸皮质量比为7∶3,培养温度30 ℃,料液比1∶2.0（g∶mL）,培养时间96 h,接种量为10%。在此优化条件下,羧甲基纤维素酶活力达8.95 IU/g,滤纸酶酶活力达2.00 IU/g。     

绿色木霉Sn-9106固态发酵中药残渣产纤维素酶研究

对绿色木霉Sn-9106固态发酵中药残渣产纤维素酶的可行性进行了研究.以滤纸酶为纤维素酶活性指标,麸皮、蛋白胨、KH2PO4添加量为影响因子,先采取单因素实验确定3种影响因子的最佳浓度,然后通过相应面法(RSM)优化产酶最佳条件.结果表明,当最大酶活力为12.3 IU/g时所需固体发酵基质中麸皮、蛋白胨及KH2PO4的浓度分别为19.80g/L、2.06g/L、2.90g/L,与优化前培养基相比,纤维素酶产量提高了近3倍.     

INCREASED GLUCOAMYLASE PRODUCTION USING AGRICULTURAL BY-PRODUCTS

ABSTRACT Media prepared from agricultural by-products including malt, wheat bran, corn steep liquor and soybean flour, were found to be an excellent substrate for proliferation of Aspergillus niger #57. Glucoamylase yields obtained using various combinations of the above materials were ten to fifteen times higher than those obtained uisng semi-synthetic media. A medium comprising 10%wheat bran extract and 8% defatted soybean flour gave the highest enzyme yield of 42 IU/ml as compared with a yield of 2.8 IU/ml obtained using optimal concentrations of glucose and peptone.     

黑曲霉液体深层发酵产纤维二糖酶的研究

纤维二糖酶（cellobiase）是纤维素酶系中的重要组分之一,目前由里氏木霉（Trichoderma reesei）生产的纤维素酶制剂中纤维二糖酶的活力明显偏低,限制了纤维素的糖化效率。本文采用一个黑曲霉菌株（Aspergillus niger ZU-04）,在液态发酵条件下生产纤维二糖酶,对主要的发酵工艺参数进行了研究,结果表明,培养基中添加1.0%的麸皮对纤维二糖酶的形成有明显的促进作用;葡萄糖、玉米浆粉的适宜浓度分别为2.0%、0.3%;变温培养缩短了产酶周期,培养4d,酶活力达到最高,为6.23IU/mL。采用黑曲霉纤维二糖酶与里氏木霉纤维素酶协同水解酸预处理后的玉米芯,当纤维素酶用量为20IU/g底物时,纤维二糖酶活力和滤纸酶活力比例为0.43,2d酶解得率达到91.1%。     

毕赤酵母液态发酵产木聚糖酶条件研究

用麦麸、米糠农业废弃物作为主要原料生产木聚糖酶,对毕赤酵母液态发酵产木聚糖酶的条件进行研究。结果表明,最适产酶条件:以质量浓度20%的麦麸作为碳源,4%酵母浸膏作为氮源,调节初始pH值5.5,培养温度30℃,摇瓶发酵装液量6%,培养时间130 h,在此条件下毕赤酵母液态发酵产木聚糖酶最高活力达到2192 IU/mL。     

克劳氏芽孢杆菌S-4菌株固态发酵产碱性果胶酶

对克劳氏芽孢杆菌(Bacillusclausii)S 4菌株产碱性果胶酶的固态发酵条件进行了优化,并对酶的部分性质进行了分析,结果表明,以甜菜粕为碳源和酶的诱导物,酵母膏和麸皮作氮源较适宜。固体培养基的组成:甜菜粕5 0g ,麸皮2 0 g ,KH2 PO40 0 15g ,MgSO4·7H2 O 0 2 5g ,Na2 CO3 0 12g ,水2 0mL ;培养温度4 0℃;发酵时间72h ;产酶率可达2 30 0u/g(甜菜粕)。该酶具有果胶水解酶和果胶裂解酶的活性,在pH 10 5 ,反应温度6 0℃时酶活力最高,在pH9 5～11 0范围内,温度4 0℃以下较稳定。1 0mmol/L的Ca2 + 、Tween 80和SDS对该酶有明显的激活作用,Mn2 + 、Cu2 + 、Zn2 + 对其有强烈的抑制作用。     

Optimization of Chitosanase Production by <Emphasis Type="Italic">Trichoderma koningii</Emphasis> sp. Under Solid-State Fermentation

This study aimed at the optimization of the production of chitosanase in solid culture. Trichoderma koningii sp., an entomopathogenic fungus, was used to produce chitosanase under solid-state fermentation using a mixture of wheat bran and chitosan. The incubation period; addition of moistening water and culture medium composition were optimized. The protocol to extract the enzyme was also optimized. The optimal conditions for chitosanase production by T. koningii were obtained using a mixture of 3.0 g of wheat bran and 1.5 g of chitosan, with the addition of 2.5 mL of moistening water (pH 5.5) and of 2.5 mL of saline solution (pH 5.5) containing NaNO₃ (1.0 g/L), (NH₄)₂HPO₄ (1.0 g/L), MgSO₄.7H₂O (1.0 g/L), and NaCl (1.0 g/L). Optimal enzyme extraction was carried out adding 20 mL of sodium acetate buffer (200 mM, pH 5.5) at 30 °C under orbital agitation at 150 rpm for 6 min. The optimized production yielded 4.84 IU/gds.     

Development of a solid-state fermentation process for production of an alpha amylase with potentially interesting properties

Ca-independency with potential activity and stability at low pH are among the most interesting characteristics of α-amylase in starch industry. In this attempt the synergetic effect of low pH on activity of crude Ca-independent α-amylase isolated from a native Bacillus sp. KR-8104 in solid-state fermentation (SSF) was studied using wheat bran (WB) as a substrate. The effects of different parameters including moisturizing agents, solid substrate to moisture ratio, particle size, incubation temperature and period, inoculum (v/w) and supplementation with 1% (w/w) different carbon and nitrogen sources on enzyme production were investigated. Maximum enzyme production of 140 U/g dry fermented substrate was obtained from wheat bran moistened with tap water at a ratio of 1:1.5 and supplemented with 1% (w/w) NH₄NO₃ and 1% (w/w) lactose after 48 h incubation at 37 °C. Even though the production of α-amylase was lower at 40 and 45 °C, the viable cell count was higher. In addition response surface methodology (RSM) was applied to find optimum conditions of temperature and pH on crude amylase activity. Using central composite design (CCD) a quadratic mathematical model equation was derived for the prediction of enzyme activity. The results showed that the model was in good agreement with experimental results, with R² = 0.90 (p < 0.0001) and the low pH has a synergetic effect on enzyme activity at higher temperature.     

Solid-State Bioconversion of Passion Fruit Waste by White-Rot Fungi for Production of Oxidative and Hydrolytic Enzymes

Yellow passion fruit waste (YPFW) is an abundant food waste in Brazil, rich in carbohydrates. The aim of the present work was to obtain useful oxidative and hydrolytic enzymes. YPFW solid-state cultures were done using the food-grade white-rot fungi Pleurotus ostreatus, Pleurotus pulmonarius, Macrocybe titans, Ganoderma lucidum, and Grifola frondosa. Under the conditions used in this work, the main enzymes produced by the fungi were laccases, pectinases, and aryl-β-d-glycosidases (β-glucosidases, β-xylosidases, and β-galactosidases). Laccases were produced by all fungi, and in this respect, the YPFW was as good as substrate as wheat bran, the most commonly substrate used for white-rot fungi cultivation. M. titans was the best producer of pectinase in YPFW cultures, while P. ostreatus and P. pulmonarius were the best producers of aryl-β-glycosidases in both YPFW and wheat bran cultures.     

耐热子囊菌产木聚糖酶及酶学性质的研究

对 1株耐热子囊菌 (Thermoascusaurantiacus)固态发酵产木聚糖酶的工艺条件及酶学性质进行了研究。确立了适宜的产酶基质为 :麸皮 3 0 %、玉米芯 3 5 %、玉米皮 3 5 %、(NH4 ) 2 SO4 2 %、尿素 0 5 %、KH2 PO4 0 5 %、MgSO4 ·7H2 O 0 2 %、初始含水量 65～ 70 %。 45℃培养 5d ,木聚糖酶活力最高可达 1 0 3 2 1IU/g(干曲 )。该木聚糖酶最适反应温度为 70℃ ,最适pH4 8;在 pH3 0～ 7 0 ,温度低于 65℃时稳定性能较好。可被Fe2 +、Mg2 +、Zn2 +激活 ,而被Co2 +、Fe3+、Mn2 +抑制。     

诱导物对出芽短梗霉木聚糖酶活力和阿魏酰低聚糖合成的调控影响

以麦麸为原料诱变选育的不产黑色素出芽短梗霉为发酵菌株,利用其发酵过程中合成的木聚糖酶水解麦麸纤维,制备阿魏酰低聚糖(FOs)。研究碳源、氮源、金属离子和表面活性剂等诱导物对出芽短梗霉木聚糖酶活力和FOs合成的影响,以探明各物质对出芽短梗霉木聚糖酶活力和FOs合成的影响;利用正交试验设计方法研究各物质添加量对出芽短梗霉产酶和FOs的影响,确定芽短梗霉发酵制备FOs的最佳培养基。结果表明:50g/L麦麸处理液中添加15g/L葡萄糖、1g/L蛋白胨和1g/L玉米浆,FOs产量和木聚糖酶活力最高分别达到627nmol/L和52.66IU/mL。