Accelerated biodecolorization and detoxification of synthetic textile dye Acid Maroon V by bacterial consortium under redox mediator system.

The treatment of textile industrial wastewater is an important concern owing to its negative impact on the biosphere. The present study highlighted dye decolorization potential of bacterial consortium EDPA containing Enterobacter dissolvens AGYP1 and Pseudomonas aeruginosa AGYP2 in the presence of redox mediators. Rapid decolorization of Acid Maroon V (100 mg l-1) was achieved in the presence of lawsone compared to other redox mediators. The dye decolorization was best fitted with first order kinetics with higher reaction kinetics (k1 = 0.328 h-1) and regression coefficient (R2 = 0.979). The removal of dye by the consortium was 1.47 times faster in 8 h with 0.01 mM lawsone. The consortium EDPA was able to decolorize 1200 mg l-1 concentration of dye with apparent R max , K m and R max /K m values 1000 mg l-1 h-1, 5000 mg l-1 and 0.2 h-1, respectively. The lawsone-mediated system could decolorize the dye 80.44% in 10 h at the end of 11 dye spiking cycle. The superior biodecolorization of 14 different textile dyes was obtained in the presence of lawsone-mediated system. The intracellular enzyme activities of azoreductase, NADH-DCIP reductase, laccase, manganese peroxidase and lignin peroxidase increased significantly. The sequential microaerophilic-aerobic incubation resulted into 89.31% reduction of total aromatic amines. The microbial toxicity, phytotoxicity and genotoxicity measurements revealed biotransformation of toxic nature of dye Acid Maroon V into non-toxic metabolites by the action of consortium EDPA, and thus its suitability for biotreatment of dye containing industrial effluents. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03466-6.

Utilization of laccase immobilized CdO nanoparticles in synthesis of industrially potent organics and their molecular docking studies.

In the present study, Tricholoma giganteum AGHP laccase was immobilized on amino-functionalized cadmium oxide nanoparticles (CdO NPs) which was carried out by glutaraldehyde. The synthesized CdO NPs were characterized by using transmission electron microscopy (TEM), Energy dispersive X-ray analysis (EDXA) and X-ray diffraction (XRD) analysis which reflected the NPs had an average size of 35 nm with hexagonal and irregular shapes. Fourier transform infra-red (FTIR) study of laccase with amino-functionalized CdO (lac-CdO) NPs confirmed the crosslinking of laccase with CdO NPs. With immobilized laccase, a shift in pH (5.5) and temperature (35 â„ƒ) optima was observed, when compared to free laccase (pH 4.5, 30 â„ƒ). Lac-CdO NPs displayed 1.15 times higher stability (90 ± 0.47%) than free laccase (78 ± 0.69%) at optimum pH of 5.5. Immobilized laccase showed 1.19-fold improvement in thermal stability and 2.25-fold increment in half-life after 3 h of incubation at 50 â„ƒ as compared to free laccase. Recycling capability study demonstrated that lac-CdO NPs were able to retain 85 ± 0.68% of relative activity at the end of 20th 2,2-azinobis-3-ethylbenzthiozoline-6-sulfonic acid (ABTS) oxidation cycle. In addition, lac-CdO NPs showed remarkable reusability in catalysing various organic synthesis reactions even after several cycle of catalysis. Furthermore, the interactions of organic synthesis reactions and interacted residues were observed by assessing the molecular docking poses of T. giganteum laccase with substrates. The obtained results would be advantageous to develop a biocatalyst over a chemical catalyst for effective synthesis of potent organics having industrial importance.

Evaluation of Bioactive Attributes and Emulsification Potential of Exopolysaccharide Produced by a Brown-rot Fungus Fomitopsis meliae AGDP-2.

Mushrooms possess wide array of biologically active secondary metabolites and have been traditionally used for their medicinal properties. Exopolysaccharide (EPS) is one of such bioactive metabolites. The bioactive attributes and emulsification capabilities of the exopolysaccharides produced by a novel brown-rot fungus Fomitopsis meliae AGDP-2 under submerged fermentation has been thoroughly investigated in the present study. Exopolysaccharide displayed anti-oxidant activities in dose dependent manner with the maximum scavenging of ABTS radicals (42.45%), DPPH radicals (75.34%), Hydroxyl radicals (63.64%), Superoxide anion radical (76.54%) and Ferric Reducing Antioxidant Power with IC50 value of 231 µg/mL. Additionally, evaluation of anti-proliferative properties revealed that EPS significantly inhibited the proliferation of HepG2 and HT-29 cancer cells followed by moderate inhibition of HeLa and MCF-7 cancer cell lines and quite less inhibition of L-132 and KB cell lines. The IC50 values of EPS for the abovementioned cell lines are 9.465 µg/mL, 11.25 µg/mL, 38.98 µg/mL, 87.78 µg/mL, 2061 µg/mL and 2361 µg/mL respectively. Moreover EPS also possess good anti-microbial as well as anti-biofilm properties. The studies on emulsification potential described that EPS is good emulsifier of different vegetable oils and the emulsion formed was quite stable up to 144 h.

Preparation, characterization and its potential applications in Isoniazid drug delivery of porous microcrystalline cellulose from banana pseudostem fibers.

Banana pseudostem, a cellulose-rich by-product, is regarded as an important agricultural waste during the process of banana production. Microcrystalline cellulose was successfully prepared from banana pseudostem using acid hydrolysis method. Microcrystalline cellulose was characterized through various techniques such as XRD, TGA, SEM, FTIR and antioxidant activity to explore the possible applications in the pharmaceutical industries especially as a drug delivery vehicle. The investigation revealed that the derived microcrystalline cellulose is non-aggregated, short rods with high crystallinity index 67% and stable up to 347 °C. FTIR spectroscopy showed that hydrolysis treatments are efficient for the removal of lignin and hemicellulose content. Microcrystalline cellulose exhibited good antioxidant activity 90.29% at 100 µg/ml. In vitro studies for the drug release were carried out in simulated intestinal fluid (SIF) using Isoniazid drug. The study proves that microcrystalline cellulose can be directly obtained from banana pseudostem which is not only beneficial to reduce the cost of traditional microcrystalline cellulose but is also conducive to the value-added utilization of the pseudostem.

Exploiting the potential of metal and solvent tolerant laccase from Tricholoma giganteum AGDR1 for the removal of pesticides.

Laccase from previously reported hardwood degrading fungus, Tricholoma giganteum AGDR1, was isolated, identified at molecular level, biochemically characterized and also utilized for pesticide degradation. Laccase gene is comprised of 3752 bp, which encompassed 742-bp of 5' flanking upstream sequence with 12 introns and 12 exons. Mature enzyme possesses 391 amino acids and signal peptide, which is determined to be monomeric protein with an apparent molecular weight of 41 kDa and 6.45 pI. Higher optimal activities were observed at 45 °C and pH 3.0 and surprisingly, it exhibited more than 20% of relative activity at pH 1.5. Purified laccase was tolerant to 100 mM of metals (i.e. Se, Pb, Cu, Cr and Cd), organic solvents (ethyl acetate, methanol, ethanol and acetone) and potent inhibitors (hydroxylamine, thiourea, NaF and Na-azide) as compared to reported laccases. It was able to degrade 29%, 7% and 72% of chlorpyrifos, profenofos and thiophanate methyl within 15 h, respectively. Molecular docking analysis revealed that higher binding efficacy of these pesticides is observed with H83, H320, A95, V384, and P366 which are presented near to the catalytic site. Based on the results, T. giganteum AGDR1 laccase can be applied for the potential remediation and industrial applications under harsh conditions.

Studies on a better laccase-producing mutant of Fusarium incarnatum LD-3 under solid substrate tray fermentation.

Forty-seven (47) mutant strains were generated from the wild-type fungus, Fusarium incarnatum strain LD-3 after exposure to ultraviolet radiation (UV) and a further seventeen (17) mutants were generated after exposure to ethyl methane sulfonate (EMS). Amongst these, the mutant strain, identified as UC-14, was the most promising laccase producer and produced threefold more laccase than the wild strain LD-3. Solid substrate tray fermentation using wheat straw and rice bran showed a twofold increase in laccase productivity and a fivefold loss of total organic matter (TOM) by mutant UC-14 over the wild strain LD-3. The mutant strain UC-14 also showed 25% and 54% weight loss of TOM after 36 days of fermentation which was 10% higher than the wild-type LD-3. Scanning electron microscopy suggested that the delayed condidiation in mutant strain UC-14 may be responsible for better laccase production.

Assessment of white rot fungus mediated hardwood degradation by FTIR spectroscopy and multivariate analysis.

Evaluating the biomass degradation using fast, validate and sensitive techniques for exploratory purposes of biofuel production has been developed since last decade. Thus, we assessed the degradation of two Indian hardwoods using FTIR and chemometric approaches. Two white rot fungi, namely Pseudolagarobasidium acaciicola AGST3 and Tricholoma giganteum AGDR1, were selected among twenty-one fungal isolates for higher hardwood degradation. In the screening, P. acaciicola AGST3 and T. giganteum AGDR1 depicted the dry woody mass loss of 20.51% and 22.38%, respectively. Cellulose crystallinity of P. acaciicola AGST3 treated hardwoods was 4-fold lower than untreated hardwoods, showing the higher cellulose degradation efficiency. P. acaciicola AGST3 treated samples exhibited maximum deviation of guaiacyl units of lignin, cellulose and hemicelluloses. T. giganteum AGDR1 treated hardwoods showed maximum deviation of guaiacyl- and syringyl- units of lignin and hemicelluloses. Multivariate approach revealed the degradation patterns and preferences are varied based on the fungi and hardwood. The approach used in the present study can certainly distinguish the variations among the different biomass samples that having similar composition. Additionally, higher lignin degradability of these fungi can be used in biomass pretreatment, which significantly utilized to produce second-generation biofuels.

Biosorption Potential of Phanerochaete chrysosporium for Arsenic, Cadmium, and Chromium Removal from Aqueous Solutions.

Efficient degradation of hazardous contaminants from contaminated water is the major challenge for researchers, wherein heavy metals are the prominent contaminants. Consequently, the assessment of multimetal removal is necessary using efficient biosorbant. In this work, the capability of Phanerochaete chrysosporium is evaluated for the individual and simultaneous removal of heavy metals. Individual and simultaneous removal of As, Cd, and Cr is optimized using response surface methodology based on the central composite design by changing the variables, i.e., pH, fungal biomass, and metal concentration. Optimization of the individual metal removal study reveals that fungus effectively absorbs As (29.95 mg L-1), Cd (18.1 mg L-1), and Cr (26.34 mg L-1) at 6.1, 5.64, and 4.15 of pH, respectively. Similarly, As (14.18 mg L-1), Cd (4.53 mg L-1), and Cr (9.28 mg L-1) are absorbed by fungal hyphae simultaneously within 1 h. Changes in the morphology of fungal hyphae are detected in metal absorbed samples as compared to the control hyphae. Interaction of metal-absorbed fungal hyphae is analyzed using FTIR spectroscopy, revealing that the proteins, carbohydrates, and fatty acids present in the fungal cell are interacted with metals. The model white rot fungi used in the present study can be applied efficiently for the multimetal removal in effluent treatment plants.

Biological treatment of textile dyes by agar-agar immobilized consortium in a packed bed reactor.

The decolorization of Acid Maroon V was investigated using bacterial consortium EDPA containing Enterobacter dissolvens AGYP1 and Pseudomonas aeruginosa AGYP2 immobilized in different entrapment matrices. The consortium displayed 96% removal of dye (100 mg/l) within 6 h when immobilized in agar-agar. Under optimum concentrations of agar-agar (3.0% w/v) and cell biomass (0.9 g% w/v), the consortium displayed decolorization for 18 successive batches of Acid Maroon V and also decolorized 14 other different textile dyes. A packed bed reactor under batch mode showed 89% decolorization of dye after 56 repetitive cycles. Under continuous flow mode, maximum color removal was achieved with bed length of 36 cm, hydraulic retention time of 2.66 h, and dye concentration of 100 mg/l. Additionally, the reactor decolorized relatively higher concentrations (100-2000 mg/l) of dye. The synthetic dye wastewater containing five textile dyes was decolorized 92% with 62% COD reduction using an immobilized consortium.

Production of bioethanol using agricultural waste: banana pseudo stem.

India is amongst the largest banana (Musa acuminata) producing countries and thus banana pseudo stem is commonly available agricultural waste to be used as lignocellulosic substrate. Present study focuses on exploitation of banana pseudo stem as a source for bioethanol production from the sugars released due to different chemical and biological pretreatments. Two fungal strains Aspergillus ellipticus and Aspergillus fumigatus reported to be producing cellulolytic enzymes on sugarcane bagasse were used under co-culture fermentation on banana pseudo stem to degrade holocellulose and facilitate maximum release of reducing sugars. The hydrolysate obtained after alkali and microbial treatments was fermented by Saccharomyces cerevisiae NCIM 3570 to produce ethanol. Fermentation of cellulosic hydrolysate (4.1 g%) gave maximum ethanol (17.1 g/L) with yield (84%) and productivity (0.024 g%/h) after 72 h. Some critical aspects of fungal pretreatment for saccharification of cellulosic substrate using A. ellipticus and A. fumigatus for ethanol production by S. cerevisiae NCIM 3570 have been explored in this study. It was observed that pretreated banana pseudo stem can be economically utilized as a cheaper substrate for ethanol production.

Production of bioethanol using agricultural waste: banana pseudo stem

India is amongst the largest banana (Musa acuminata) producing countries and thus banana pseudo stem is commonly available agricultural waste to be used as lignocellulosic substrate. Present study focuses on exploitation of banana pseudo stem as a source for bioethanol production from the sugars released due to different chemical and biological pretreatments. Two fungal strains Aspergillus ellipticus and Aspergillus fumigatus reported to be producing cellulolytic enzymes on sugarcane bagasse were used under co-culture fermentation on banana pseudo stem to degrade holocellulose and facilitate maximum release of reducing sugars. The hydrolysate obtained after alkali and microbial treatments was fermented by Saccharomyces cerevisiae NCIM 3570 to produce ethanol. Fermentation of cellulosic hydrolysate (4.1 g%) gave maximum ethanol (17.1 g/L) with yield (84%) and productivity (0.024 g%/h) after 72 h. Some critical aspects of fungal pretreatment for saccharification of cellulosic substrate using A. ellipticus and A. fumigatus for ethanol production by S. cerevisiae NCIM 3570 have been explored in this study. It was observed that pretreated banana pseudo stem can be economically utilized as a cheaper substrate for ethanol production.

Biochemical and kinetic study of laccase from Ganoderma cupreum AG-1 in hydrogels.

In the present study, three different types of hydrogels i.e., (poly (-acrylamide)/alginate (P (AAm)/Alg), poly (acrylamide-N-isopropylacrylamide) (P (AAm-NIPA)), and poly (acrylamide-N-isopropylacrylamide)/alginate (P (AAm-NIPA)/Alg)) were synthesized by acrylamide, alginate, and N-isopropylacrylamide for the entrapment of laccase. The hydrogel-entrapped and free laccase showed optimum temperature of 50 °C for the oxidation of ABTS, but the entrapped laccase showed high temperature, pH, and storage stability as compared to the free enzyme. The K m values of free laccase, (P (AAm)/Alg)-L, (P (AAm-NIPA))-L, and (P (AAm-NIPA)/Alg)-L were found to be 0.13, 0.28, 0.33, and 0.50 mM, respectively. The V max values of free laccase, (P (AAm)/Alg)-L, (P (AAm-NIPA))-L, and (P (AAm-NIPA)/Alg)-L were found to be 22.22 × 10(2), 5.55 × 10(2), 5.0 × 10(2), and 4.54 × 10(2) mM/min, respectively. The entrapped laccase hydrogels were used for the decolorization of Reactive Violet 1 dye, with 39 to 45 % decolorization efficiency till the 10th cycle.

Purification and characterization of an extracellular laccase from solid-state culture of Pleurotus ostreatus HP-1.

A native isolate of Pleurotus ostreatus HP-1 (Genbank Accession No. EU420068) was found to have an excellent laccase producing ability. The extracellular laccase was purified to electrophoretic homogeneity from copper sulphate induced solid-state fermentation medium by ammonium sulphate precipitation and ion-exchange chromatography. The enzyme was determined to be monomeric protein with an apparent molecular mass of 68,420 kDa, and an isoelectric point (pI) of 3.5. The inductively coupled plasma spectroscopy showed a presence of iron, zinc and copper in the purified enzyme. The absorption spectrum in the range of 200-700 nm showed the maximum absorption at 610 nm characteristic of fungal laccase and corresponding to the presence of type I copper atom. The laccase was stable at different temperatures up to 70 °C and retained 61 % activity at 50 °C. The enzyme reaction was inhibited by cysteine; sodium azide and EDTA. The enzyme oxidized various known laccase substrates, its lowest Km value being for ortho-dianisidine and highest Kcat and Kcat/Km for ABTS. The purified laccase exhibited different pH optima for different substrates. The N-terminal sequence did not show any similarity with N-terminal sequence of other species of genera Pleurotus.

Possible role of laccase from Fusarium incarnatum UC-14 in bioremediation of Bisphenol A using reverse micelles system.

Bisphenol A [2,2 bis (4 hydroxyphenyl) propane] is widely used in the variety of industrial and residential applications such as the synthesis of polymers including polycarbonates, epoxy resins, phenol resins, polyesters and polyacrylates. BPA has been recognized as an Endocrine Disrupting Chemicals (EDC), thus it is necessary to assess its biodegradability or fate in the natural environment. In general, environmental pollutant such as BPA does not dissolve in aqueous media, owing to their high hydrophobicity, and hence non-aqueous catalysis can be employed to enhance biodegradability of phenolic environmental pollutant. Purified laccase hosted in reverse micelles using ternary system of isooctane: AOT [Bis (2-ethylhexyl) sulphosuccinate sodium salt)]:water having hydration ratio (Wo) of 30 with protein concentration of 43.5 µg/ml was found to eliminate 91.43% of 200 ppm of Bisphenol A at 50 °C, pH-6.0 when incubated with laccase/Reverse Micelles system for 75 min. GC-MS analysis of isooctane soluble fractions detected the presence of 4,4'-(2 hydroxy propane 1,2 diyl) diphenol, bis (4-hydroxylphenyl) butenal and 2-(1-(4-hydroxyphenyl) vinyl) pent-2-enal indicated degradation of BPA by two oxidation steps and one ring opening step (C-C bond cleavage). Laccase/RM system exhibited several advantages for the oxidative degradation of hydrophobic phenols mainly because of the solubility of either enzyme or substrate was improved in organic media and the stable activity of laccase in organic media was achieved.

Degradation and selective ligninolysis of wheat straw and banana stem for an efficient bioethanol production using fungal and chemical pretreatment.

Lignocelluloses from agricultural, industrial, and forest residues constitute a majority of the total biomass present in the world. Environmental concerns of disposal, costly pretreatment options prior to disposal, and increased need to save valuable resources have led to the development of value-added alternate technologies such as bioethanol production from lignocellulosic wastes. In the present study, biologically pretreated (with the fungus, Pleurotus ostreatus HP-1) and chemically pretreated (with mild acid or dilute alkali) wheat straw (WS) and banana stem (BS) were subsequently subjected to enzymatic saccharification (with mixture of 6.0 U/g of filter paper cellulase and 17 U/g of ß-glucosidase) and were evaluated for bioethanol production using Saccharomyces cerevisiae NCIM 3570. Biological and chemical pretreatments removed up to 4.0-49.2 % lignin from the WS and BS which was comparatively higher than that for cellulose (0.3-12.4 %) and for hemicellulose (0.7-21.8 %) removal with an average 5.6-49.5 % dry matter loss. Enzymatic hydrolysis yielded 64-306.6 mg/g (1.5-15 g/L) reducing sugars from which 0.15-0.54 g/g ethanol was produced from Saccharomyces cerevisiae NCIM 3570.

Optimization of culture condition for enhanced decolorization and degradation of azo dye reactive violet 1 with concomitant production of ligninolytic enzymes by Ganoderma cupreum AG-1.

The strain Ganoderma cupreum AG-1 (Genbank accession no. HQ328947) isolated from the decayed wood was evaluated for its ability to decolorize azo dye reactive violet 1 as well as for the production of ligninolytic enzymes. In the initial decolorization study, the strain was capable of decolorizing 19 different azo dyes. The strain was capable of decolorizing dye over a pH range of 4.5-6 at 30 °C. The optimum pH was found to be 4.5. Various other process parameters like additional carbon and nitrogen source and initial dye concentration were also optimized. The decolorization medium was supplemented with appropriate nitrogen source (yeast extract, 5 g l-1) and carbon source (mannose, 2 g l-1); the decolorization obtained was 98 %. The pattern of enzymes involved in the biodegradation was studied and laccase and MnP were found to be the major enzymes. High laccase activity shown by G. cupreum AG-1 and its ability to decolorize dyes are a good indication of its possible use in the treatment of textile effluents.

Nutrient improvement for simultaneous production of exopolysaccharide and mycelial biomass by submerged cultivation of Schizophyllum commune AGMJ-1 using statistical optimization.

Exopolysaccharides (EPS) of fungal origin have attracted special attention from researchers due to their multifarious applications in the food and pharmaceutical industries. In the present study, optimization of the process parameters for the production of exopolysaccharide by Schizophyllum commune AGMJ-1 was studied using one factor at a time (OFAT) method, Plackett-Burman design (PBD) and response surface methodology (RSM). OFAT method revealed xylose and yeast extract to be the most effective carbon and nitrogen sources and pH 5.3 as an optimum for maximum EPS production. Xylose, yeast extract and KCl were screened as statistically significant variables for EPS production using PBD. RSM based on the central composite design estimated that maximum EPS (4.26 g L-1), mycelial biomass (14 g L-1) and specific yield (0.45 g g-1) were obtained when concentration of xylose, yeast extract and KCl were set at 2.5 g % (w/v), 0.83 g % (w/v) and 6.53 mg % (w/v), respectively, in the production medium.

Production of xylanase under solid-state fermentation by Aspergillus tubingensis JP-1 and its application.

The production of extracellular xylanase by a locally isolated strain of Aspergillus tubingensis JP-1 was studied under solid-state fermentation. Among the various agro residues used wheat straw was found to be the best for high yield of xylanase with poor cellulase production. The influence of various parameters such as initial pH, moisture, moistening agents, nitrogen sources, additives, surfactants and pretreatment of substrates were investigated. The production of the xylanase reached a peak in 8 days using untreated wheat straw with modified MS medium, pH 6.0 at 1:5 moisture level at 30 °C. Under optimized conditions yield as high as 6,887 ± 16 U/g of untreated wheat straw was achieved. Crude xylanase was used for enzymatic saccharification of agro-residues like wheat straw, rice bran, wheat bran, sugarcane bagasse and industrial paper pulp. Dilute alkali (1 N NaOH) and acid (1 N H(2)SO(4)) pretreatment were found to be beneficial for the efficient enzymatic hydrolysis of wheat straw. Dilute alkali and acid-pretreated wheat straw yielded 688 and 543 mg/g reducing sugar, respectively. Yield of 726 mg/g reducing sugar was obtained from paper pulp after 48 h of incubation.

White-rot fungal conversion of wheat straw to energy rich cattle feed.

In order to improve the digestibility and nutrient availability in rumen, wheat straw was subjected to solid state fermentation (SSF) with white-rot fungi (i.e. Pleurotus ostreatus and Trametes versicolor) and the fermented biomass (called myco-straw) was evaluated for biochemical, enzymatic and nutritional parameters. The fungal treatment after 30 days led to significant decrease (P < 0.05) in cell wall constituents viz, acid detergent fiber (ADF), neutral detergent fiber (NDF), hemicellulose, lignin and cellulose to the extent of 35.00, 38.88, 45.00, 37.48 and 37.86%, respectively in P. ostreatus fermented straw, while 30.04, 33.85, 39.90, 31.29 and 34.00%, respectively in T. versicolor fermented straw. However, maximum efficiency of fermentation in terms of low carbohydrate consumption per unit of lignin degradation, favoring cattle feed production was observed for P. ostreatus on the 10th day (17.12%) as compared with T. versicolor on the 30th day (16.91%). The myco-straw was found to contain significantly high (P < 0.05) crude protein (CP; 4.77% T. versicolor, 5.08% P. ostreatus) as compared to control straw (3.37%). Metabolizable energy (ME, MJ/kg DM), percent organic matter digestibility (OMD) and short chain fatty acids (SCFAs; mmol) production also increased considerably from control straw (4.40, 29.91 and 0.292) to a maximum up to P. ostreatus fermented straw (4.92, 33.39 and 0.376 on 20th day) and T. versicolor fermented straw (4.66, 31.74 and 0.334 on 10th day), respectively. Moreover, the myco-straw had lower organic carbon and was rich in nitrogen with lower C/N ratio as compared to control wheat straw. Results suggest that the fungal fermentation of wheat straw effectively improved CP content, OM digestibility, SCFAs production, ME value and simultaneously lowered the C/N ratio, thus showing potential for bioconversion of lignin rich wheat straw into high energy cattle feed.

Optimization of media components for laccase production by litter dwelling fungal isolate Fusarium incarnatum LD-3.

Laccase production by solid state fermentation (SSF) using an indigenously isolated litter dwelling fungus Fusarium incarnatum LD-3 was optimized. Fourteen medium components were screened by the initial screening method of Plackett-Burman. Each of the components was screened on the basis of 'p' (probability value) which was above 95% confidence level. Ortho-dianisidine, thiamine HCl and CuSO(4) . 5 H(2)O were identified as significant components for laccase production. The Central Composite Design response surface methodology was then applied to further optimize the laccase production. The optimal concentration of these three medium components for higher laccase production were (g/l): CuSO(4) . 5 H(2)O, 0.01; thiamine HCl, 0.0136 and ortho-dianisidine, 0.388 mM served as an inducer. Wheat straw, 5.0 g was used as a solid substrate. Using this statistical optimization method the laccase production was found to increase from 40 U/g to 650 U/g of wheat straw, which was sixteen times higher than non optimized medium. This is the first report on statistical optimization of laccase production from Fusarium incarnatum LD-3.