{Reference Type}: Journal Article
{Author}: Aslam, Sadia; Asgher, Muhammad
{Year}: 2011
{Title}: Partial purification and characterization of ligninolytic enzymes produced by Pleurotus ostreatus during solid state fermentation
{Tag}: 0
{Star}: 0
{Journal}: AFRICAN JOURNAL OF BIOTECHNOLOGY
{Volume}: 10
{Issue}: 77
{Pages}: 17875-17883
{ISBN/ISSN}: 1684-5315
{Keywords}: WHITE-ROT FUNGUS; PHANEROCHAETE-CHRYSOSPORIUM; LACCASE PRODUCTION; PEROXIDASE; OXIDATION; DEGRADATION; MECHANISM; Ligninolytic enzymes; Pleurotus ostreatus; 2,2 azinobis 3-ethylbenzthiazoline 6 sulphonate (ABTS); solid state fermentation
{Abstract}: The production of ligninolytic enzymes including laccase, manganese peroxidase and lignin peroxidase from Pleurotus ostreatus was studied under different parameters using solid state fermentation. Maximum production of enzymes was observed after 7 days in solid state fermentation (SSF) medium containing 5 g wheat straw (66% w/w moisture) in a still culture SSF. Different parameters had a significant effect on enzyme production. Maximum laccase (455.11 U/mL), manganese peroxidase (210.77 U/mL) and lignin peroxidase (54.50 U/mL) were produced when wheat straw (5 g) at 66% moisture (w/w) was used with 4 mL inoculum at pH 4.5 and 30 degrees C in the presence of 1% (v/v) glycerol as carbon source, 0.2% w/w urea as nitrogen source, 1% (w/v) 2, 2 azinobis 3-ethylbenzthiazoline 6 sulphonate (ABTS) as an inducer for laccase and 1% (w/v) MnSO(4) for manganese peroxidase, 1% (w/v) CuSO(4) as metal ion for laccase and Mn(+) for manganese peroxidase. Both enzymes laccase and manganese peroxidase produced by Pleurotus ostreatus were partially purified by ammonium sulphate precipitation followed by gel filtration chromatography. Additionally, the protein content of the recovered supernatants was also noted. Purification results showed an increase in purity up to 3.37 and 3.07 fold for laccase and manganese peroxidase, respectively. The Michaelis constant, K(M) was 62 and 33 mu M for laccase and manganese peroxidase, respectively. Lignin peroxidase was not produced during solid state fermentation of ligniocellulosic material by P. ostreatus because this fungus is a laccase producer. The activators ABTS and MnSO(4) proved good for laccase and MnP production. This shows that SSF parameters had a significant influence on catalytic activity of ligninolytic enzymes produced by P. ostreatus under still conditions.
{Author Address}: Univ Agr Faisalabad, Dept Chem & Biochem, Ind Biotechnol Lab, Faisalabad, Pakistan; Univ Agr Faisalabad, Dept Chem & Biochem, Ind Biotechnol Lab, Faisalabad, Pakistan
{Database Provider}: Web of Science SCI
{Language}: English
{Country}: Pakistan

{Reference Type}: Journal Article
{Author}: Zhu, YouShuang; Zhang, HaiBo; Zhang, YingLong; Huang, Feng
{Year}: 2011
{Title}: Lignocellulose degradation, enzyme production and protein enrichment by Trametes versicolor during solid-state fermentation of corn stover
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{Journal}: AFRICAN JOURNAL OF BIOTECHNOLOGY
{Volume}: 10
{Issue}: 45
{Pages}: 9182-9192
{ISBN/ISSN}: 1684-5315
{Keywords}: IN-VITRO DIGESTIBILITY; RESPONSE-SURFACE METHODOLOGY; LIGNIN DEGRADATION; PLEUROTUS-OSTREATUS; LACCASE PRODUCTION; WHEAT-STRAW; OPTIMIZATION; FUNGI; BIOCONVERSION; IMPROVEMENT; Corn stover; central composite design; laccase; ligninolysis; Trametes versicolor; crude protein
{Abstract}: Microbial conversion of corn stover by white rot fungi has the potential to increase its ligninolysis and nutritional value, thereby transforming it into protein-enriched animal feed. Response surface methodology was applied to optimize conditions for the production of lignocellulolytic enzymes by Trametes versicolor during solid-state fermentation of corn stover, as well as enhance ligninolysis and increase the crude protein content. The effects of an additional carbon source (glucose), copper sulfate (CuSO4) and initial moisture content on lignocellulolytic enzymes, changes in chemical constituents and the crude protein content of corn stover were investigated. T. versicolor produced high laccase, moderate xylanase, and low CMCase activity, whereas neither LiP nor MnP activity was detected. An overall 20-fold increase in laccase activity (45.1 U/g corn stover) was achieved under the optimized conditions. The maximum degradation of lignin and hemicellulose was up to 34.8 and 21.9%, respectively. However, the maximum cellulose loss was less than 10.5%. The crude protein content of the fermented corn stover was doubled under the optimized conditions. Therefore, T. versicolor is a potential organism for laccase production using solid-state fermentation, as well as the simultaneous enhancement of delignification and improvement of the crude protein content in corn stover.
{Author Address}: Shandong Univ, State Key Lab Microbial Technol, Jinan 250100, Peoples R China; Shandong Univ, State Key Lab Microbial Technol, Jinan 250100, Peoples R China; Chinese Acad Sci, Qingdao Inst Bioenergy & Bioproc Technol, Qingdao 266071, Peoples R China; Shandong Univ, State Key Lab Microbial Technol, Jinan 250100, Peoples R China; Shandong Inst Commerce & Technol, Dept Biotechnol, Jinan 250103, Peoples R China; Shandong Univ, State Key Lab Microbial Technol, Jinan 250100, Peoples R China
{Database Provider}: Web of Science SCI
{Language}: English
{Country}: Peoples R China; Peoples R China; Peoples R China

{Reference Type}: Journal Article
{Author}: Patrick, Ferdinandi; Mtui, Godliving; Mshandete, Anthony Manoni; Kivaisi, Amelia
{Year}: 2011
{Title}: Optimization of laccase and manganese peroxidase production in submerged culture of Pleurotus sajor-caju
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{Star}: 0
{Journal}: AFRICAN JOURNAL OF BIOTECHNOLOGY
{Volume}: 10
{Issue}: 50
{Pages}: 10166-10177
{ISBN/ISSN}: 1684-5315
{Keywords}: WHITE-ROT FUNGI; LIGNIN-DEGRADING ENZYMES; TRAMETES-VERSICOLOR; PHANEROCHAETE-CHRYSOSPORIUM; EXTRACELLULAR LACCASE; ENHANCED FORMATION; DECOLORIZATION; OSTREATUS; COPPER; DEGRADATION; White-rot fungi; optimization; Pleurotus sajor-caju; laccase; manganese peroxidase; submerged fermentation; immobilization
{Abstract}: A white-rot fungus, Pleurotus sajor-caju, was isolated from coastal Tanzania and screened for crude lignolytic enzymes production using rhemazol brilliant blue R (RBBR) dye, 2,2-azino-bis (3-ethylbenzthiazoline)-6-sulfonate (ABTS) and guaiacol in a semi-solid medium. Laccase (Lac) and manganese peroxidase (MnP) were detected by alpha-napthol and pyrogallol solutions, respectively, on the guaiacol supplemented semi-solid media. The effect of temperature, pH, carbon, nitrogen, Cu(2+), 2,5-xylidine, ferulic acid, Mn(2+) and immobilization using Luffa cylindrica sponges in submerged culture fermentations were investigated for maximum enzymes production. After 7 days of incubation, 83 to 100% oxidation of RBBR, ABTS and guaiacol was observed. With optimized culture conditions, the fungal filtrate had maximum Lac and MnP activities of 80 and 0.94 U/ml, respectively compared to 0.62 and 0.0003 U/ml obtained with non-optimized ones; amounting to 129 and 3133 times increase in Lac and MnP activities, respectively. The improved crude enzymes activities, RBBR decolourization, ABTS and guaiacol oxidation capabilities of P. sajor-caju show its potential as a source of industrial enzymes for biotechnological applications.
{Author Address}: Univ Dar Es Salaam, Coll Nat & Appl Sci, Dept Mol Biol & Biotechnol, Dar Es Salaam, Tanzania; Univ Dar Es Salaam, Coll Nat & Appl Sci, Dept Mol Biol & Biotechnol, Dar Es Salaam, Tanzania; Univ Dar Es Salaam, Coll Nat & Appl Sci, Dept Mol Biol & Biotechnol, Dar Es Salaam, Tanzania; Univ Dar Es Salaam, Coll Nat & Appl Sci, Dept Mol Biol & Biotechnol, Dar Es Salaam, Tanzania
{Database Provider}: Web of Science SCI
{Language}: English
{Country}: Tanzania

{Reference Type}: Journal Article
{Author}: Mbassi, Yves M. E. L.; Marie, Solange Evehe B.; Mbacham, Wilfred; Muluh, John P.
{Year}: 2011
{Title}: Heat stable peroxidases from Vigna species (V)
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{Star}: 0
{Journal}: AFRICAN JOURNAL OF BIOTECHNOLOGY
{Volume}: 10
{Issue}: 16
{Pages}: 3168-3175
{ISBN/ISSN}: 1684-5315
{Keywords}: HORSERADISH-PEROXIDASE; THERMAL-STABILITY; PLEUROTUS-ERYNGII; CALCIUM; THERMOSTABILITY; ARTICHOKE; PROTEINS; ENZYME; Vigna; peroxidase; shoots; thermal stability
{Abstract}: Shoots of three landraces of a Vigna species from two climatic areas of Cameroon were evaluated for their content of heat-resistant peroxidases. The peroxidase activity in the three landraces was detected with a greater catalytic efficiency for oxidation of O-dianisidine relative to ABTS (2, 2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) at pH 5. For example, with respect to the landrace named Vs1 in this study, V(max)/Km for O-dianisidine was around 0.68 compared to ABTS (0.01). The results revealed a great thermal stability of peroxidases of a landrace cultivated in the hotter northern part of Cameroon (average temperature of 29 degrees C). Residual activity in this landrace was 67, 34 and 3.4% after pre-incubation for 1 h at 70, 75 and 80 inverted perpendicular C respectively. For this same landrace, peroxidase activity did not significantly reduce after pre-incubation for 1 week at 55 degrees C and was more than 60% after 3 weeks at 55 degrees C. After storage for 365 days at room temperature (25 degrees C), peroxidase activity remained above 30% for all three Vigna landraces, but higher at 47% for Vigna from the hotter area. Such thermal stability of peroxidases was not observed in maize, beans or peanuts in this study. The addition of calcium chloride in the crude extract of the more resistant Vigna landrace led to a total inhibition of thermal inactivation, after pre-incubation for 10 min at 80 degrees C. These findings make this Vigna landrace a source of highly useful peroxidases in biotechnology, especially as part of bench top diagnostic kits in Africa that do not require cold chains.
{Author Address}: Univ Yaounde 1, Lab Publ Hlth Biotechnol, Yaounde, Cameroon; Univ Yaounde 1, Lab Publ Hlth Biotechnol, Yaounde, Cameroon; Univ Yaounde 1, Lab Publ Hlth Biotechnol, Yaounde, Cameroon; Univ Yaounde 1, Lab Publ Hlth Biotechnol, Yaounde, Cameroon
{Database Provider}: Web of Science SCI
{Language}: English
{Country}: Cameroon