Optimization of decolorization of methylene blue (MB) dye by lignin peroxidase (LiP) enzyme produced by white-rot fungus Phanerochaete chrysosporium using sewage treatment plant (STP) sludge as a major substrate was carried out in the laboratory. Optimization by the one-factor-at-a-time (OFAT) and statistical approach was carried out to determine the process conditions on optimum decolorization of MB dye using LiP enzyme in static mode. The OFAT method indicated that the optimum conditions for decolorization of MB dye (removal: 14-40%) was at temperature 55 degrees C, pH 5.0 with hydrogen peroxide (H(2)O(2)) concentration 4.0mM, MB dye concentration 20mg/L and LiP activity 0.487U/ml. The addition of veratryl alcohol to the reaction mixtures did not contribute any further increases in decolorization. The initial concentration of MB and the activity of LiP enzyme were further optimized using response surface methodology (RSM). The contour and surface plots suggested that the optimum initial concentration of MB and LiP activity predicted were 15mg/L and 0.687U/ml, respectively for the removal of 65%. The validation of the model showed that the decolorization process gave the higher removal of 90% in agitation mode compared to the static mode with 65% for 60min of incubation time by LiP enzyme.
A laboratory-scale study was carried out to produce lignin peroxidase (ligninase) by white rot fungus (Phanerochaete chrysosporium) using sewage-treatment-plant (STP) sludge as the major substrate. The optimization was done using full-factorial design (FFD) with agitation and aeration as the two parameters. Nine experiments indicated by the FFD were fermented in a stirred-tank bioreactor for 3 days. A second-order quadratic model was developed using the regression analysis of the experimental results with the linear, quadratic, and interaction effects of the parameters. Analysis of variance (ANOVA) showed a high coefficient of determination (R (2)) value of 0.972, thus indicating a satisfactory fit of the quadratic model with the experimental data. Using statistical analysis, the optimum aeration and agitation rates were determined to be 2.0 vvm and 200 rpm, respectively, with a maximum activity of 225 U l(-1) in the first 3 days of fermentation. The validation experiment showed the maximum activity of lignin peroxidase was 744 U l(-1) after 5 days of fermentation. The results for the tests of the stability of lignin peroxidase showed that the activity was more than 80% of the maximum for the first 12 h of incubation at an optimum pH of 5 and temperature of 55 degrees C.
Cellulase production was carried out by solid state bioconversion (SSB) method using rice straw, a lignocellulosic material and agricultural waste, as the substrate of three Trichoderma spp. and Phanerochaete chrysosporium in lab-scale experiments. The results were compared to select the best fungi among them for the production of cellulase. Phanerochaete chrysosporium was found to be the best among these species of fungi, which produced the highest cellulase enzyme of 1.43 IU/mL of filter paper activity (FPase) and 2.40 IU/mL of carboxymethylcellulose activity (CMCase). The "glucosamine" and "reducing sugar" parameters were observed to evaluate the growth and substrate utilization in the experiments. In the case of Phanerochaete Chrysosporium, the highest glucosamine concentration was 1.60 g/L and a high concentration of the release of reducing sugar was measured as 2.58 g/L obtained on the 4th day of fermentation. The pH values were also recorded. The range of the pH was about 5.15 to 5.56 in the case of Phanerochaete Chrysosporium.
Matched MeSH terms: Phanerochaete/enzymology*; Phanerochaete/growth & development
A laboratory-scale study of bioconversion of local lignocellulosic material, oil palm biomass (OPB) was conducted by evaluating the enzyme production through microbial treatment in solid state bioconversion (SSB). OPB in the form of empty fruit bunches (EFB) was used as a solid substrate and treated with the white-rot fungus, Phanerochaete chrysosporium, to produce ligninase. The results showed that the highest ligninase activity of 400.27 U/liter was obtained at day 12 of fermentation. While the optimum study indicated the enzyme production of 1472.8 U/liter with moisture content of 50%, 578.7 U/liter with 10% v/w of inoculum size, and 721.8 U/liter with co-substrate concentration of 1% (w/w) at days 9, 9 and 12 of fungal treatment, respectively. The parameters glucosamine and reducing sugar were observed to evaluate the growth and substrate utilization in the experiment.
Matched MeSH terms: Phanerochaete/enzymology; Phanerochaete/growth & development
Natural and environmental-friendly disposal of wastewater sludge is a great concern. Recently, biological treatment has played prominent roles in bioremediation of complex hydrocarbon- rich contaminants. Composting is quite an old biological-based process that is being practiced but it could not create a great impact in the minds of concerned researchers. The present study was conducted to evaluate the feasibility of the solid-state bioconversion (SSB) processes in the biodegradation of wastewater sludge by exploiting this promising technique to rejuvenate the conventional process. The Indah Water Konsortium (IWK) domestic wastewater treatment plant (DWTP) sludge was considered for evaluation of SSB by monitoring the microbial growth and its subsequent roles in biodegradation under two conditions: (i) flask (F) and (ii) composting bin (CB) cultures. Sterile and semi-sterile environments were allowed in the F and the CB, respectively, using two mixed fungal cultures, Trichoderma harzianum with Phanerochaete chrysosporium 2094 (T/P) and T. harzianum with Mucor hiemalis (T/M) and two bulking materials, sawdust (SD) and rice straw (RS). The significant growth and multiplication of both the mixed fungal cultures were reflected in soluble protein, glucosamine and color intensity measurement of the water extract. The color intensity and pH of the water extract significantly increased and supported the higher growth of microbes and bioconversion. The most encouraging results of microbial growth and subsequent bioconversion were exhibited in the RS than the SD. A comparatively higher decrease of organic matter (OM) % and C/N ratio were attained in the CB than the F, which implied a higher bioconversion. But the measurement of soluble protein, glucosamine and color intensity exhibited higher values in the F than the CB. The final pH drop was higher in the CB than the F, which implied that a higher nitrification occurred in the CB associated with a higher release of H+ ions. Both the mixed cultures performed almost equal roles in all cases except the changes in moisture content.
Bioprotein is one of the useful products obtained from biotechnology invention. It is a promising replacement for the commercial fish feed supplement. In this study, the enrichment of the bioprotein content after solid state fermentation using palm kernel cake and seaweed by the white rot fungus: Phanerochaete chrysoporium and yeast: Candida utilis was carried out. The growth media components were selected from 11 types of media using Plackett-Burman design (hereinafter PBD) and were optimized by one-factor-at-a-time (OFAT) method with bioprotein concentration (mg/g) as the response. From the screening result using PBD, three media components, namely K2HPO4, CuSO4.5H2O and MnSO4.H2O were selected for further optimization using OFAT method because of their positive contributions to the response. The final results showed that 5.0 g/L K2HPO4, 3.0 g/L CuSO4.5H2O and 0.1 g/L MnSO4.H2O were there to be the optimum media constituents with 9.0 g/L, MgSO4.7H2O, 0.1 g/L, CaCl2.H2O, 3.0 g/L FeSO4.7H2O and 3.0 g/L peptone as fixed compositions. At this optimum concentration, the protein increment of 11% was observed as compared to the results determined in the screening using PBD. The study revealed the benefits of using mixed cultures in improving the protein concentrations which can be used as nutritious fish feed.
Ethanol was produced via the simultaneous saccharification and fermentation (SSF) of dilute sodium hydroxide treated corn stover. Saccharification was achieved by cultivating either Phanerochaete chrysosporium or Gloeophyllum trabeum on the treated stover, and fermentation was then performed by using either Saccharomyces cerevisiae or Escherichia coli K011. Ethanol production was highest on day 3 for the combination of G. trabeum and E. coli K011 at 6.68 g/100g stover, followed by the combination of P. chrysosporium and E. coli K011 at 5.00 g/100g stover. SSF with S. cerevisiae had lower ethanol yields, ranging between 2.88 g/100g stover at day 3 (P. chrysosporium treated stover) and 3.09 g/100g stover at day 4 (G. trabeum treated stover). The results indicated that mild alkaline pretreatment coupled with fungal saccharification offers a promising bioprocess for ethanol production from corn stover without the addition of commercial enzymes.
This study was conducted to evaluate the effect of an eminent decay fungus, Phanerocheate chrysosporium of organic residues on wastewater sludge for its improvement through decomposition and separation of waste particles by Liquid State Bioconversion (LSB). The effect of fungal treatment was compared to uninoculated (Control) at three different harvests 7, 14 and 21 days after inoculation (DAI). The observed results showed that the weight loss and solid content of wastewater sludge were significantly influenced by Phanerocheate chrysosporium. Both parameters were highly influenced at 7 DAI. The COD and pH of wastewater sludge were also highly influenced by fungal treatment.
Kinetic analysis of solid-state fermentation (SSF) of fruit peels with Phanerochaete chrysosporium and Schizophyllum commune mixed culture was studied in flask and 7 kg capacity reactor. Modified Monod kinetic model suggested by Haldane sufficiently described microbial growth with co-efficient of determination (R2) reaching 0.908 at increased substrate concentration than the classical Monod model (R2 = 0.932). Leudeking-Piret model adequately described product synthesis in non-growth-dependent manner (R2 = 0.989), while substrate consumption by P. chrysosporium and S. commune fungal mixed culture was growth-dependent (R2 = 0.938). Hanes-Woolf model sufficiently represented α-amylase and cellulase enzymes synthesis (R2 = 0.911 and 0.988); α-amylase had enzyme maximum velocity (Vmax) of 25.19 IU/gds/day and rate constant (Km) of 11.55 IU/gds/day, while cellulase enzyme had Vmax of 3.05 IU/gds/day and Km of 57.47 IU/gds/day. Product yield in the reactor increased to 32.65 mg/g/day compared with 28.15 mg/g/day in shake flask. 2.5 cm media thickness was adequate for product formation within a 6 day SSF in the tray reactor.
Banana peel (BP) is a major waste produced by fruit processing industries. Pre-treatment of BP at different temperatures led to 40% reduction in saponin at 100 °C (from 9.5 to 5.7 mg/g). Sequential mixed culture of Phanerochaete chrysosporium (P. chrysosporium) and Candida utilis (C. utilis) gave highest protein enrichment (88.93 mg/g). There is 26% increase in protein synthesis (from 88.93 to 111.78 mg/g) after media screening. Inclusion of KH2PO4, FeSO4·7H2O, wheat flour and sucrose in the media contributed positively to protein synthesis, while elevated concentration of urea, peptone, K2HPO4, KCl, NH4H2PO4, and MgSO4.7H2O are required to reach optimum protein synthesis. Total soluble sugar (TSS), total reducing sugar (TRS) and total carbohydrate (CHO) consumption varied with respect to protein synthesis in all experimental runs. Optimum protein synthesis required 6 days and inclusion of 5% sucrose, 0.6% NH4H2PO4, 0.4% KCl, and 0.5% MgSO4·7H2O as concentration media constituents to reach 140.95 mg/g protein synthesis equivalent to 300% increase over the raw banana peel protein content (35.0 mg/g).