樟绒枝霉(Malbranchea cinnamomea)固体发酵产木聚糖酶的发酵条件优化

[目的] 研究樟绒枝霉(Malbranchea cinnamomea) CAU521利用农业废弃物固体发酵产木聚糖酶的发酵条件.[方法]采用单因素试验法优化影响菌株产酶的各个条件,包括碳源种类、氮源种类、初始pH、初始水分含量、培养温度及发酵时间共6个因素.[结果]获得的最佳产酶条件为:稻草为发酵碳源、2％(W/W)的酵母提取物为氮源、初始pH 7.0、初始水分含量80％和发酵温度45℃.在此条件下发酵6d后木聚糖酶的酶活力达到13 120 U/g干基碳源.[结论]樟绒枝霉固体发酵产木聚糖酶的产酶水平高,生产成本低,具有潜在的工业化应用前景.     

Utilization of prawn waste for chitinase production by the marine fungus Beauveria bassiana by solid state fermentation

Prawn waste, a chitinous solid waste of the shellfish processing industry, was used as a substrate for chitinase production by the marine fungus Beauveria bassiana BTMF S10, in a solid state fermentation (SSF) culture. Theprocess parameters influencing SSF were optimized. A maximum chitinase yield of 248.0 units/g initial dry substrate (U/gIDS) was obtained in a medium containing a 5:1 ratio (w/v) of prawn waste/sea water, 1% (w/w) NaCl,2.5% (w/w) KH2PO4, 425–600m substrate particle size at 27°C, initial pH 9.5, and after 5 days of incubation. The presence of yeast extract reduced chitinase yield. The results indicate scope for the utilization of shellfish processing (prawn) waste for the industrial production of chitinase by using solid state fermentation.     

Production of extracellular alkaline alpha-amylase by solid state fermentation with a newly isolated Bacillus sp

Production of alkaline alpha-amylase employing our laboratory isolate, Bacillus sp., under solid state fermentation, was optimized. The effect of wheat bran and lentil husk was examined. Lentil husk exhibited the highest enzyme production. The appropriate incubation time, inoculum size, moisture level, and buffer solution level were determined. Maximum yields of 216,000 and 172,800 U/g were achieved by employing lentil husk and wheat bran as substrates in 0.1 M carbonate/bicarbonate buffer at pH 10.0 with 30% initial moisture level at 24 h. Inoculum size and buffer solution level were found to be 20% and 1:0.5 for two solid substrates.     

Production of Extracellular Alkaline α‐Amylase by Solid State Fermentation with a Newly Isolated Bacillus sp.

Abstract

Production of alkaline α‐amylase employing our laboratory isolate, Bacillus sp., under solid state fermentation, was optimized. The effect of wheat bran and lentil husk was examined. Lentil husk exhibited the highest enzyme production. The appropriate incubation time, inoculum size, moisture level, and buffer solution level were determined. Maximum yields of 216,000 and 172,800 U/g were achieved by employing lentil husk and wheat bran as substrates in 0.1 M carbonate/bicarbonate buffer at pH 10.0 with 30% initial moisture level at 24 h. Inoculum size and buffer solution level were found to be 20% and 1:0.5 for two solid substrates.     

Exoglucanase production by Aspergillus niger grown on wheat bran

β-Exoglucanase production on the lignocellulosic material, wheat bran, by Aspergillus niger under solid state fermentation (SSF) on a laboratory scale was investigated. Different fermentation parameters, such as moisture content, initial pH, temperature, depth of the substrate, and inoculum size on exoglucanase production were optimized. Moisture content of 40 %, pH of 7.0, substrate depth of 1.0 cm, inoculum size of 2?×?10⁶ spores/g of wheat bran, and temperature at 30 °C were optimal for maximum production of exoglucanase. Maximum yields of exoglucanase with 28.60 FPU/g of wheat bran were obtained within 3 days of incubation under optimal conditions.     

Xylanase production by Burkholderia sp. DMAX strain under solid state fermentation using distillery spent wash

Xylanase production by a newly isolated strain of Burkholderia sp. was studied under solid state fermentation using anaerobically treated distillery spent wash. Response surface methodology (RSM) involving Box-Behnken design was employed for optimizing xylanase production. The interactions between distillery effluent concentration, initial pH, moisture ratio and inoculum size were investigated and modeled. Under optimized conditions, xylanase production was found to be in the range of 5200-5600 U/g. The partially purified enzyme recovered after ammonium sulphate fractionation showed maximum activity at 50 degrees C and pH 8.6. Kinetic parameters like Km and Vmax for xylan were found to be 12.75 mg/ml and 165 micromol/mg/min. In the presence of metal ions such as Ca2+, Co2+, Mn2+, Ba2+, Mg2+ and protein disulphide reducing agents such as beta-mercaptoethanol and dithiotheritol (DTT) the activity of enzyme increased, where as strong inhibition of enzyme activity was observed in the presence of Cu2+, Ag+, Fe2+ and SDS. The crude enzyme hydrolysed lignocellulosic substrate, wheat bran as well as industrial pulp.     

Solid state fermentation for production of α-amylase byBacillus megaterium 16M

Summary The ratio of buffer to wheat bran, incubation temperature and initial pH influence -amylase production byBacillus megaterium 16M under solid state fermentation. The enzyme, with pH and temperature optima at 6.0 and 70°C, is formed at a level of 30,000 units/g dry bacterial bran without coproduction of proteases and cellulases.     

Use of coconut coir fibers as an inert solid support for production of cyclosporin A

In the present study, coconut coir was evaluated as an inert support for the production of cyclosporin A (CyA) using Tolypocladium inflatum MTCC 557 by solid state fermentation. Initially, four different inert supports such as coconut coir, polyurethane foam, polystyrene beads, and sugarcane baggase were screened using different production media as moistening agents for the maximum production of CyA. Different parameters such as fermentation time, carbon sources, moisture content, pH, and inoculum size were optimized. It was observed that coconut coir impregnated with medium modified with glycerol as carbon source, pH 6, at 80% moisture content, and inoculum size of 2.5 mL/2.5 g support produced 2641 mg/kg of CyA after 12 days as compared to 998 mg/kg before optimization. The yields were further increased to 3597 mg/kg substrate with addition of combination of amino acids after 48 h of fermentation.     

Potential of Aspergillus oryzae CFTRI 1480 for producing proteinase in high titres by solid state fermentation

Aspergillus oryzae CFTRI 1480, an isolate from a spoiled moist sample of casein, produced 59,105 units of an extracellular proteinase/g dry mouldy bran (DMB) at 72 h in an arbitrarily formulated wheat bran medium in a solid state fermentation system. The enzyme production was significantly affected by mineral salt content and pH of the liquid used for moistening the wheat bran. Enzyme titres were enhanced 1.34-fold with the addition of 0.4% corn starch. Optimization of key parameters, i.e., initial moisture content, age and size of inoculum, increased the enzyme production to 191,869 units/g DMB and reduced the fermentation time to 48 h. Such high titres in a simple medium, surpassing most of the literature reports, indicate the industrial importance of the culture. The properties of acetone-precipitated enzyme, viz, the optimum pH of 10.0, more than 95% activity between pH 7.0 and 10.0, temperature optimum at 55° C and more than 90% activity between 10 and 27°C, are similar to those of commercially available fungal proteinases employed in animal feed, leather and other industries. Correspondence to: B. K. Lonsane     

Response surface optimization of mixed substrate solid state fermentation for the production of lovastatin by Monascus purpureus

The objective of this work is to enhance the production of lovastatin using Monascus purpureus MTCC 369 in mixed substrate solid state fermentation using various solid substrates and to optimize the combination of the solid substrates by response surface methodology. Solid state fermentation was conducted in a 250 mL Erlenmeyer flask at 30°C for 14 days with initial moisture content of 40% and inoculum size of 10% active culture. Barley, long grain rice and sago starch were found to be the suitable substrates producing maximum lovastatin of 193.7 mg, 190.2 mg and 180.9 mg/g of dry solids. These substrates were further used in various combinations as designed by the central composite design for enhancing the lovastatin production using Monascus purpureus. To the best of our knowledge this is the first report on the production of lovastatin using a mixed substrate solid state fermentation using Monascus purpureus.     

Production and optimization of process parameters for alkaline protease production by a newly isolated Bacillus sp. under solid state fermentation

Production of alkaline protease employing the laboratory isolate, Bacillus sp. under solid state fermentation (SSF) was optimized. The effect of wheat bran and lentil husk was examined. Wheat bran showed highest enzyme production. The appropriate incubation time, inoculum size, moisture level and buffer solution level were determined. Maximum yields of 429.041 and 168.640 U g⁻¹ were achieved by employing wheat bran and lentil husk as substrates in 0.1 M carbonate/bicarbonate buffer at pH 10 with 30 and 40% initial moisture level at 24 h. Inoculum size and buffer solution level were found to be 20 and 25% and 0.5:1 for wheat bran and lentil husk, respectively.     

OPTIMIZATION OF SOLID-STATE FERMENTATION FOR PHYTASE PRODUCTION BY Thermomyces lanuginosus USING RESPONSE SURFACE METHODOLOGY

A strain of Thermomyces lanuginosus, isolated from hot spring water in Turkey, was studied for optimization of phytase production using solid-state fermentation. Effects on fermentation of different production parameters such as substrate type, moisture, culture time, and inoculum size were investigated using a one-factor-at-a-time approach. Central composite design (CCD) of response surface methodology was applied for the optimization of four factors (culture temperature, initial pH, aeration area, age of seeding culture) that were affecting phytase production by Thermomyces lanuginosus in rice bran. Maximum phytase activity was achieved by using rice bran. The optimum levels of variables that supported maximum enzyme activity were moisture 70%, culture time 7 days, inoculum size 40%, culture temperature 55°C, initial pH 7.5, aeration area 30%, age of seeding culture 5 days, sucrose 1%, and ZnSO₄ 2.5 mM. An overall 10.83-fold enhancement in phytase activity (0.30 to 3.248 U) was attained due to the optimization.     

Impact of process parameters on chitinase production by an alkalophilic marine Beauveria bassiana in solid state fermentation

A chitinolytic fungus, Beauveria bassiana was isolated from marine sediment and significant process parameters influencing chitinase production in solid state fermentation using wheat bran were optimised. The organism was strongly alkalophilic and produced maximum chitinase at pH 9·20. The NaCl and colloidal chitin requirements varied with the type of moistening medium used. Vegetative (mycelial) inoculum was more suitable than conidial inoculum for obtaining maximal enzyme yield. The addition of phosphate and yeast extract resulted in enhancement of chitinase yield. After optimisation, the maximum enzyme yield was 246·6 units g⁻¹ initial dry substrate (U gIDS⁻¹). This is the first report of the production of chitinase from a marine fungus.     

Enhanced production of raw starch degrading enzyme using agro-industrial waste mixtures by thermotolerant Rhizopus microsporus for raw cassava chip saccharification in ethanol production

In the present study, solid-state fermentation for the production of raw starch degrading enzyme was investigated by thermotolerant Rhizopus microsporus TISTR 3531 using a combination of agro-industrial wastes as substrates. The obtained crude enzyme was applied for hydrolysis of raw cassava starch and chips at low temperature and subjected to nonsterile ethanol production using raw cassava chips. The agro-industrial waste ratio was optimized using a simplex axial mixture design. The results showed that the substrate mixture consisting of rice bran:corncob:cassava bagasse at 8?g:10?g:2?g yielded the highest enzyme production of 201.6?U/g dry solid. The optimized condition for solid-state fermentation was found as 65% initial moisture content, 35°C, initial pH of 6.0, and 5?×?10⁶ spores/mL inoculum, which gave the highest enzyme activity of 389.5?U/g dry solid. The enzyme showed high efficiency on saccharification of raw cassava starch and chips with synergistic activities of commercial α-amylase at 50°C, which promotes low-temperature bioethanol production. A high ethanol concentration of 102.2?g/L with 78% fermentation efficiency was achieved from modified simultaneous saccharification and fermentation using cofermentation of the enzymatic hydrolysate of 300?g raw cassava chips/L with cane molasses.     

Xylanase production under solid-state fermentation and its characterization by an isolated strain of <Emphasis Type="Italic">Aspergillus foetidus</Emphasis> in India

Summary A locally isolated strain of Aspergillus foetidus MTCC 4898 was studied for xylanase (EC 3.2.1.8) production using lignocellulosic substrates under solid state fermentation. Corncobs were found as the best substrates for high yield of xylanases with poor cellulase production. The influence of various parameters such as temperature, pH, moistening agents, moisture level, nitrogen sources and pretreatment of substrates were evaluated with respect to xylanase yield, specific activity and cellulase production. Influence of nitrogen sources on protease secretion was also examined. Maximum xylanase production (3065 U/g) was obtained on untreated corncobs moistened with modified Mandels and Strenberg medium, pH 5.0 at 1 5 moisture levels at 30 °C in 4 days of cultivation. Submerged fermentation under the same conditions gave higher yield (3300 U/g) in 5 days of cultivation, but productivity was less. Ammonium sulphate fractionation yielded 3.56-fold purified xylanase with 76% recovery. Optimum pH and temperature for xylanase activity were found to be 5.3 and 50 °C respectively. Kinetic parameters like K_m and V_max were found to be 3.58 mg/ml and 570 μmol/mg/min. Activity of the enzyme was found to be enhanced by cystiene hydrochloride, CoCl₂, xylose and Tween 80, while significantly inhibited by Hg⁺⁺, Cu⁺⁺ and glucose. The enzyme was found to be stable at 40 °C. The half life at 50 °C was 57.53 min. However thermostability was enhanced by glycerol, trehalose and Ca⁺⁺. The crude enzyme was stable during lyophilization and could be stored at less than 0 °C.     

Solid-state fermentation for Trichokonins production from Trichoderma koningii SMF2 and preparative purification of Trichokonin VI by a simple protocol

Trichokonins are peptaibols produced by Trichoderma koningii SMF2. The main isoforms are Trichokonin VI, Trichokonin VII and Trichokonin VIII. The solid-state fermentation (SSF) was applied for the production of Trichokonin VI. The fermentation factors, which included inoculum size, incubation temperature, initial moisture content and initial pH, were investigated and optimized by response surface methodology. The maximum Trichokonin VI production (4.07mg/g dry substrate) was achieved by employing inoculum size of 18%, incubation temperature at 24.3 degrees C, initial moisture content of 77.5% and initial pH at 5.0. Furthermore, gel filtration and preparative HPLC were used for separation of Trichokonin VI from a crude extract of the T. koningii SMF2 culture. With this preparative purification protocol under optimized fermentation conditions, 146.20mg Trichokonin VI was obtained from 1kg solid cultures. It has been shown that the obtained Trichokonin VI is more than 95% in purity. This is the first report on optimization of peptaibols production in SSF with high content. An efficient method for the preparative purification of Trichokonin VI is also proposed.     

Review of solid state fermentation for lignocellulolytic enzyme production: challenges for environmental applications

Within the context of increasing environmental concern, energy production from lignocellulosic substrates is gaining great interest. Enzymes have proven their efficiency in the degradation of the lignocellulosic complex but their use remains limited in environmental applications such as anaerobic digestion mainly due to their prohibitive cost. Therefore, solid state fermentation (SSF) emerges as an interesting alternative for the in situ production of lignocellulolytic enzymes. Various research efforts on the lab scale optimization of SSF are discussed. They are presented according to the type of inoculum used in the process: bacterial species and fungal species under both mesophilic and thermophilic conditions. In general, parameters that impact the SSF process include: substrate type and particle size, substrate pretreatment, inoculum, nutrient supplementation, moisture content, pH, aeration, temperature and mixing. Using different substrates, authors aim at maximizing enzyme production taking into account one to several of the indicated operational parameters. The reviewed research puts forward the adaptation of the operational parameters, enzyme production cost and loading, enzyme mixture quality and efficiency and finally reactor design as the main challenges for environmental large-scale application.     

Green gram husk--an inexpensive substrate for alkaline protease production by Bacillus sp. in solid-state fermentation

Alkaline protease production under solid-state fermentation was investigated using isolated alkalophilic Bacillus sp. Among all agro-industrial waste material evaluated, green gram husk supported maximum protease production. Solid material particle size regulated the enzyme production and yield was improved with the supplementation of carbon and nitrogen sources to the solid medium. Optimum enzyme production was achieved with 1.5% maltose and 2.0% yeast extract with 371% increase than control. Glucose did not repressed enzyme production but inorganic nitrogen sources showed little negative impact. The physiological fermentation factors such as pH of the medium (pH 9.0), moisture content (140%), incubation time (60 h) and inoculum level played a vital role in alkaline protease production. The enzyme production was found to be associated with the growth of the bacterial culture.     

Evaluation of alpha-galactosidase biosynthesis by Streptomyces griseoloalbus in solid-state fermentation using response surface methodology

Aim: The present study was aimed at evaluating the effects of the three crucial factors, galactose concentration, inoculum size and moisture content, on α‐galactosidase production by the filamentous actinobacterium Streptomyces griseoloalbus in solid‐state fermentation. Methods and Results: Central Composite design was adopted to derive a statistical model for the optimization of fermentation conditions. Maximum α‐galactosidase yield (117 U g^–1 of dry fermented substrate) was obtained when soya bean flour supplemented with 1·5% galactose and with initial moisture content of 40% was inoculated with 1·9 × 10⁶ CFU g^?1 initial dry substrate. Conclusions: The model was valid and could result in considerably enhanced enzyme yield. Significance and Impact of the Study: The results indicated a cost effective method for the production of α‐galactosidase using soya bean flour. This is the first report on exploitation of the potential of filamentous bacterium for the production of α‐galactosidase, an enzyme having versatile applications.     

Production of tannase by solid-state fermentation

An attempt has been made to optimize the production of enzyme tannase by solid state fermentation (SSF) using the organism Rhizopus oryzae. The best favourable conditions for enzyme production include initial pH 5 with 4 days of incubation period at 40°C and 72% humidity, and 10 g wheat bran soaked in 2.5% tannic acid.