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.     

Solid-state fermentation for the production of Monascus pigments from jackfruit seed

The aim of the present work was to investigate the feasibility of jackfruit seed powder as a substrate for the production of pigments by Monascus purpureus in solid-state fermentation (SSF). A pigment yield of 25ODUnits/g dry fermented substrate was achieved by employing jackfruit seed powder with optimized process parameters such as 50% initial moisture content, incubation temperature 30 degrees C, 9x10(4)spores/g dry substrate inoculum and an incubation period of seven days. The color of the pigments was stable over a wide range of pH, apparently due to the buffering nature of the substrate, which could be a significant point for its scope in food applications. To the best of our knowledge this is the first report on pigment production using jackfruit seed powder in solid-state fermentation (SSF).     

Xylanase production in solid state fermentation by Aspergillus niger mutant using statistical experimental designs

The initial moisture content, cultivation time, inoculum size and concentration of basal medium were optimized in solid state fermentation (SSF) for the production of xylanase by an Aspergillus niger mutant using statistical experimental designs. The cultivation time and concentration of basal medium were the most important factors affecting xylanase activity. An inoculum size of 5 x 10(5) spores/g, initial moisture content of 65%, cultivation time of 5 days and 10 times concentration of basal medium containing 50 times concentration of corn steep liquor were optimum for xylanase production in SSF. Under the optimized conditions, the activity and productivity of xylanase obtained after 5 days of fermentation were 5,071 IU/g of rice straw and 14,790 IU l(-1) h(-1), respectively. The xylanase activity predicted by a polynomial model was 5,484 IU/g of rice straw.     

Influence of cultivating conditions on the alpha-galactosidase biosynthesis from a novel strain of Penicillium sp. in solid-state fermentation

AIMS: The work is intended to achieve optimum culture conditions of alpha-galactosidase production by a mutant strain Penicillium sp. in solid-state fermentation (SSF). METHODS AND RESULTS: Certain fermentation parameters involving incubation temperature, moisture content, initial pH value, inoculum and load size of medium, and incubation time were investigated separately. The optimal temperature and moisture level for alpha-galactosidase biosynthesis was found to be 30 degrees C and 50%, respectively. The range of pH 5.5-6.5 was favourable. About 40-50 g of medium in 250-ml flask and inoculum over 1.0 x 10(6) spores were suitable for enzyme production. Seventy-five hours of incubation was enough for maximum alpha-galactosidase production. Substrate as wheat bran supplemented with soyabean meal and beet pulp markedly improved the enzyme yield in trays. CONCLUSIONS: Under optimum culture conditions, the alpha-galactosidase activity from Penicillium sp. MAFIC-6 indicated 185.2 U g(-1) in tray of SSF. SIGNIFICANT AND IMPACT OF THE STUDY: The process on alpha-galactosidase production in laboratory scale may have a potentiality of scaling-up.     

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.     

Microbial production of extra-cellular phytase using polystyrene as inert solid support

Aspergillus ficuum TUB F-1165 and Rhizopus oligosporus TUB F-1166 produced extra-cellular phytase during solid-state fermentation (SSF) using polystyrene as inert support. Maximal enzyme production (10.07 U/g dry substrate (U/gds) for A. ficuum and 4.52 U/gds for R. oligosporus) was observed when SSF was carried out with substrate pH 6.0 and moisture 58.3%, incubation temperature 30 degrees C, inoculum size of 1.3 x 10(7) spores/5 g substrate, for 72 h for A. ficuum and with substrate pH 7.0 and moisture 58.3%, incubation temperature 30 degrees C, inoculum size of 1 x 10(6) spores/5 g substrate for 96 h for R. oligosporus. Results indicated scope for production of phytase using polystyrene as inert support.     

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.     

Efficient conversion of high concentration of glycerol to Monacolin K by solid-state fermentation of Monascus purpureus using bagasse as carrier

High concentration of glycerol was used as the sole carbon source for efficient production of Monacolin K (MK) by solid-state fermentation (SSF) of Monascus purpureus 9901 using agricultural residue (bagasse), as an inert carrier. A comparative study showed that MK production in SSF was about 5.5 times higher than that of submerged fermentation when 26 % of glycerol was used, which may be due to the formation of glycerol concentration gradients in the inert carrier and less catabolite repression in SSF. For enhancement of MK yield in SSF, the effects of different influential variables, such as glycerol concentration, nitrogen source and its concentration, initial moisture content, inoculum size and particle size of bagasse, were systematically examined. All the factors mentioned above had an effect on the MK production in SSF to some extent. The maximal yield of MK (12.9 mg/g) was achieved with 26 % glycerol, 5 % soybean meal, 51 % initial moisture content, 20 % inoculum size and 1 mm particle size of bagasse. The results in this study may expand our understanding on the application of SSF using agricultural residue as carrier for production of useful microbial metabolites, especially the efficient conversion of high concentration of glycerol to MK by Monascus purpureus.     

Solid state fermentation for production of α-amylase by a thermotolerant Bacillus subtilis from hot-spring water

The production of extracellular α-amylase by thermotolerant Bacillus subtilis was studied in solid state fermentation (SSF). The effect of wheat bran (WB) and rice husk (RH) was examined. The appropriate incubation period, moisture level, particle size and inoculum concentration was determined. Maximum yields of 159,520 and 21,760 U g⁻¹ were achieved by employing WB and RH as substrates in 0.1 M phosphate buffer at pH 7 with 30% initial moisture content at 24 and 48 h. Particle size and inoculum concentration were found to be 1000 μm, 20% and 500 μm, 15% for WB and RH, respectively. Enzyme yield was 7.3-fold higher with WB medium compared with RH.     

Studies on the production of nigerloxin using agro-industrial residues by solid-state fermentation

Nigerloxin, a new and potent lipoxygenase inhibitor, was discovered in our laboratory through solid-state fermentation of wheat bran by Aspergillus niger V. Teigh (MTCC-5166). The aim of this study is to investigate the possibility of using different agro-industrial residues as nutritional supplements along with wheat bran to enhance the production of nigerloxin. Nigerloxin produced by SSF was quantified spectrophotometrically at 292 nm. The results indicate that the inhibitor production was influenced by the type of solid substrate supplemented, moisture content, pH and size of the inoculum. Individually optimized supplements were tested in different combinations to determine their effects on nigerloxin production. A twofold increase in the production of nigerloxin (4.9 ± 0.3 mg gds⁻¹) was achieved by supplementing wheat bran with 10% w/w sweet lemon peel and 5% v/w methanol at optimized process parameters, that is, an initial moisture content of 65% v/w and incubation period of 6 days with an initial inoculum size of 2 ml (8 × 10⁵ spores gds⁻¹). Nigerloxin production was stable between pH of 4 and 5.     

黑曲霉固态发酵及酶解玉米皮

以玉米提取淀粉后的玉米皮渣为主要原料,采用黑曲霉固态发酵法产酶再酶解的二步法降解玉米皮中纤维素类物质。经Plackett-Burman法及响应面设计优化发酵条件得:温度30℃,接种量10%,初始水分体积分数60%,物料厚度2.47 cm,初始pH 5.79,发酵时间6 d;滤纸比酶活可达11.01 U/g,较原始酶活提高了40.61%;产酶结束后加入pH 4.8醋酸-醋酸钠缓冲液,置于50℃下酶解144 h,中性洗涤纤维与酸性洗涤纤维降解率分别为46.09%、48.82%,还原糖质量分数达到9.02%。     

Bioindicator production with <Emphasis Type="Italic">Bacillus atrophaeus</Emphasis>’ thermal-resistant spores cultivated by solid-state fermentation

Bacillus atrophaeus’ spores are used in the preparation of bioindicators to monitor the dry heat, ethylene oxide, and plasma sterilization processes and in tests to assess sterilizing products. Earlier production methods involved culture in chemically defined medium to support sporulation with the disadvantage of requiring an extended period of time (14 days) besides high cost of substrates. The effect of cultivation conditions by solid-state fermentation (SSF) was investigated aiming at improving the cost–productivity relation. Initial SSF parameters such as the type of substrate were tested. Process optimization was carried out using factorial experimental designs and response surface methodology in which the influence of different variables—particle size, moisture content, incubation time, pH, inoculum size, calcium sources, and medium composition—was studied. The results have suggested that soybean molasses and sugarcane bagasse are potential substrate and support, respectively, contributing to a 5-day reduction in incubation time. Variables which presented significant effects and optimum values were mean particle size (1.0 mm), moisture content (93%), initial substrate pH (8.0), and water as a solution base. The high-yield spore production was about 3 logs higher than the control and no significant difference in dry heat resistance was observed.     

Evaluation of the effect of process variables on the fatty acid profile of single cell oil produced by Mortierella using solid-state fermentation

This article reviews some of the aspects of single cell oil (SCO) production using solid-state fermentation (SSF) by fungi of the genus Mortierella. This article provides an overview of the advantages of SSF for SCO formation by the aforementioned fungus and demonstrates that the content of the polyunsaturated fatty acids (PUFA) depend on the type of fermentation media and culture conditions. Process variables that influence lipid accumulation by Mortierella spp. and the profile of the fatty acids are discussed, including incubation temperature, time, aeration, growth phase of the mycelium, particle size of the substrate, carbon to nitrogen ratio, initial moisture content and pH as well as supplementation of the substrate with nitrogen and oil. Finally, the article highlights future research trends for the scaled-up production of PUFAs in SSF.     

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.     

Optimization of process for the production of fungal pectinases from deseeded sunflower head in submerged and solid-state conditions

Pectinase production studies were carried out in submerged and solid-state conditions from deseeded sunflower head employing Aspergillus niger. The two potential strains of A. niger, DMF 27 for submerged and DMF 45 for solid-state were isolated by multi-step screening technique based on coefficient of pectolysis and capability of pectinase production. Process variables such as size of inoculum, pH, temperature, particle size and moisture content were optimized with an aim to achieve the maximum production of pectinases. The increased level of pectinase production was recorded at pH 5.0 and temperature 34 degrees C in submerged and solid-state conditions. The optimum inoculum size was 1x10(5)ml(-1) for submerged and 1x10(7)g(-1) for solid-state conditions. Five hundred micrometer particle size and 65% moisture content of the substrate were optimum for the maximum production of pectinases in solid-state condition. Under optimum conditions, maximum production of exo-pectinase was 34.2U/g in SSF and endo-pectinase was 12.6U/ml in SmF.     

Computerized study of interactions among factors and their optimization through response surface methodology for the production of tannin acyl hydrolase by Aspergillus niger PKL 104 under solid state fermentation

Optimization of five parameters (initial moisture, initial pH, incubation temperature, inoculum ratio and fermentation period), as per central composite rotable design falling under the response surface methodology, was attempted in a total of 32 experimental sets, after fitting the experimental data to the polynomial model of a suitable degree, for tannin acyl hydrolase production by Aspergillus niger PKL 104 in solid state fermentation system. The quantitative relation between the enzyme production and different levels of these factors was exploited to work out optimized levels of these parameters by flexible polyhedron search method and confirmed by further experimentations. The best set required 5% inoculum, 6.5 initial pH, 28 °C fermentation temperature, 62% initial moisture and 3 days fermentation time. The optima were worked out under the additional constraints for temperature ( 30 °C) and fermentation time (not more than 3 days) which are essential from industrial conditions and to pre-empt contamination, respectively. The best set resulted in 1.34 times more enzyme production than that was obtained before this optimization. Three dimensional plots, relating the enzyme production to paired factors (when other three factors were kept at their optimal levels) best described the behaviour of solid state fermentation system and the interactions between factors under optimized conditions. The model showed that the enzyme production was affected by all the five factors studied. The initial pH exhibited a positive interaction with moisture but no interaction with other factors. Initial moisture level and inoculum ratio showed negative interaction in contrast to positive interaction between inoculum ratio and fermentation period. It is thus apparent that the response surface methodology not only gives valuable information on interactions between the factors but also leads to identification of feasible optimum values of the studied factors, in addition to 99% (or more) savings on resources as compared to a full factorial traditional optimization method. Response surface methods have not been used earlier for optimizing parameters in solid state fermentation system.The authors thank Dr. S. R. Bhowmik, Director, CFTRI for the interest shown in the work. P. K. Lekha is thankful to the Council of Scientific and Industrial Research, New Delhi, India, for the award of a research fellowship.     

Enrichment of laccase production by Phoma herbarum isolate KU4 under solid-state fermentation by optimizing RSM coefficients using genetic algorithm

The process parameters were optimized to obtain enhanced enzyme activity from the fungus Phoma herbarum isolate KU4 using rice straw and saw dust as substrate under solid-state fermentation using Response surface methodology (RSM). Genetic algorithm was used to validate the RSM for maximum laccase production. Six variables, viz., pH of the media, initial moisture content, copper sulphate concentration, concentration of tannic acid, inoculum concentration and incubation time were found to be effective and optimized for enhanced production. Maximum laccase production was achieved by RSM at pH 5·0 and 86% of initial moisture content of the culture medium, 150 µmol l⁻¹ of CuSO₄, 1·5% tannic acid and 0·128 g inoculum g⁻¹ dry substrate inoculum size on the fourth day of fermentation. The highest laccase activity was observed as 79 008 U g⁻¹, which is approximately sixfold enhanced production compared to the unoptimized condition (12 085·26 U g⁻¹).     

Solid-state fermentation for gluconic acid production from sugarcane molasses by Aspergillus niger ARNU-4 employing tea waste as the novel solid support

Solid-state fermentation (SSF) was evaluated to produce gluconic acid by metal resistant Aspergillus niger (ARNU-4) strain using tea waste as solid support and with molasses based fermentation medium. Various crucial parameters such as moisture content, temperature, aeration and inoculum size were derived; 70% moisture level, 30 degrees C temperature, 3% inoculum size and an aeration volume of 2.5l min(-1) was suited for maximal (76.3 gl(-1)) gluconic acid production. Non-clarified molasses based fermentation media was utilized by strain ARNU-4 and maximum gluconic acid production was observed following 8-12 days of fermentation cycle. Different concentrations of additives viz. oil cake, soya oil, jaggary, yeast extract, cheese whey and mustard oil were supplemented for further enhancement of the production ability of microorganism. Addition of yeast extract (0.5%) was observed inducive for enhanced (82.2 gl(-1)) gluconic acid production.     

Optimization of amylase production by Aspergillus niger in solid-state fermentation using sugarcane bagasse as solid support material

Synthesis of amylase by Aspergillus niger strain UO-01 under solid-state fermentation with sugarcane bagasse was optimized by using response surface methodology and empirical modelling. The process parameters tested were particle size of sugarcane bagasse, incubation temperature and pH, moisture level of solid support material and the concentrations of inoculum, total sugars, nitrogen and phosphorous. The optimum conditions for high amylase production (457.82 EU/g of dry support) were particle size of bagasse in the range of 6–8 mm, incubation temperature and pH: 30.2°C and 6.0, moisture content of bagasse: 75.3%, inoculum concentration: 1 × 10⁷ spores/g of dry support and concentrations of starch, yeast extract and KH₂PO₄: 70.5, 11.59 and 9.83 mg/g of dry support, respectively. After optimization, enzyme production was assayed at the optimized conditions. The results obtained corroborate the effectiveness and reliability of the empirical models obtained.     

Conidia production ofBeauveria sp. by solid-state fermentation for biocontrol ofIlex paraguariensis caterpillars

Conidia production of Beauveria sp. strain LAG by solid-state fermentation (SSF) using blends of agro-industrial residues (residual potatoes and sugar-cane bagasse) was optimized with respect to cultivation conditions and the composition of substrate mixture in Erlenmeyer flasks and column-type bioreactor. With a blend of 60 % residual potatoes and 40 % sugar-cane bagasse the optimum conditions achieved were: incubation temperature 26 degrees C, initial substrate pH 6, inoculum concentration 10(7) conidia per g substrate; optimal initial moisture of the substrate was 70 % for Erlenmeyer flasks, in column-type bioreactor (with forced aeration) the optimal initial moisture of the substrate was 65 % with airflow of 60 mL/min. The highest production (1.07 x 10(10) conidia per g dry substrate) was achieved after a 10-d fermentation. The conidia were used in laboratory assays against Thelosia camina and Hylesia sp., caterpillars that are serious pests of mate plants. The mortality of T. camina was >90 % 10 d after spraying caterpillars with 1 mL conidia suspension at a concentration 10(5)-10(8)/mL. For Hylesia sp., the mortality was 70 %, 7 d after immersion in the conidia suspension containing 108 conidia per mL. Therefore, the Beauveria sp. LAG can be considered to be an important biocontrol instrument in the prospect of the Integrated Pest Management for mate plants.