Indigenous White-rot Fungi Research Articles

Potentialities of active membranes with immobilized laccase for Bisphenol A degradation

Herein, we report the development of immobilized laccase based membrane bioreactor as a novel bio-catalytic system for the degradation of emerging endocrine disruptor i.e., Bisphenol A. Two laccase forms i.e. (1) in-house isolated and purified from an indigenous white-rot fungi Pycnoporus sanguineus (CS43) and (2) Trametes versicolor (commercial laccase from Sigma-Aldrich®) were immobilized on a multi-channel ceramic membrane (1.4μm in diameter) using 4% glutaraldehyde as a cross-linking agent. The immobilization yield and bisphenol A degradation activities of immobilized laccases were recorded at various pH levels. The surface topographies of immobilized-laccase membranes were accessed by scanning electron microscopy. In this study, 100% degradation of bisphenol A (20mg/L) was achieved in less than 24h in the presence of laccase from P. sanguineus (CS43) (620.55±14.85U/L) and T. versicolor (620.55±14.85U/L). The enzymes showed an optimal activity at pH 5 and 5.4 with a degradation rate of 204.8±1.8 and 79.0±0.1μmol/min/U for P. sanguineus (CS43) and T. versicolor, respectively. In conclusion, the highest immobilization of unit per square centimeter and efficient degradation potentiality strongly recommend the newly developed immobilized laccase based membrane bioreactor as a novel tool to tackle emerging contaminants degradation issues.

Bio-based degradation of emerging endocrine-disrupting and dye-based pollutants using cross-linked enzyme aggregates.

In this study, manganese peroxidase (MnP) from an indigenous white-rot fungus Ganoderma lucidum IBL-05 was insolubilized in the form of cross-linked enzyme aggregates (CLEAs) using various aggregating agents, i.e., acetone, ammonium sulfate, ethanol, 2-propanol, and tert-butanol, followed by glutaraldehyde (GA) cross-linking. The precipitant type, MnP, and GA concentrations affected the CLEAs activity recovery and aggregation yield. Among precipitants used, acetone appeared to be the most efficient aggregation agent, providing the highest activity recovery and aggregation yield of 31.26 and 73.46%, respectively. Optimal cross-linking was noticed using 2.0% (v/v) GA and 8:1 (v/v) MnP to GA ratio at 3.0h cross-linking time under continuous agitation at 4°C. The highest recovered activity and aggregation yield were determined to be 47.57 and 81.26%, respectively. The MnP-CLEAs, thus synthesized, were tested to investigate their bio-catalytic capacity for removing two known endocrine-disrupting chemicals (EDCs), e.g., nonylphenol and triclosan in a packed bed reactor system. The insolubilized MnP efficiently catalyzed the biodegradation of both EDCs, transforming over 80% in the presence of MnP-based system. A maximal of 100% decolorization was recorded for Sitara textile (SIT-based) effluent, followed by 95.5% for Crescent textile (CRT-based) effluent, 88.0% for K&N textile (KIT-based) effluent, and 84.2% for Nishat textile (NIT-based) effluent.

Phân lập và tuyển chọn một số dòng nấm từ gỗ mục có khả năng loại màu thuốc nhuộm ở Đồng bằng sông Cửu Long

The main objective of this study was to isolate and identify indigenous white rot fungi for bioremediation of dye textile compounds. Fungal fruit body samples were collected from decaying woods in the Mekong Delta for isolation. The dye textile compound decolourisation capacity of isolated fungi was tested on MT3 (Jonathan and Fasidi, 2001) containing 500 mgL-1Brilliant Black BN or Bromophenol blue. The results showed that 54 fungal isolates were isolated from decaying wood. Twelve out of fifty four fungal isolates showed their capacity in decolourisation of Bromophenol blue. The HG1 strain was able to degrade 493 mg.L-1 Bromophenol blue, corresponding to 92% within 8 days of incubation, while fifteen out of fifty four fungal isolates showed their capacity in decolourisation of 1Brilliant Black BN. The maximum decolourisation of this compound was 99% (493 mg.L-1) within 7 days of incubation by TV13 strain . HG1 and TV13 were identified as the best candidates for decolourisation of Brilliant Black BN and Bromophenol blue compounds, respectively. Based on the results of 18S-rRNA sequences, these two candidates were genetically and relatively identified as genus of Marasmiellus. Thus, these two fungal isolates were relatively identified as Marasmiellus sp. HG1 and Marasmiellus sp. TV13.

Biochemical response of crayfish Astacus leptodactylus exposed to textile wastewater treated by indigenous white rot fungus Coriolus versicolor.

The discharge of textile effluents into the environment without appropriate treatment poses a serious threat for the aquatic organisms. The present study was undertaken to investigate biochemical response of crayfish Astacus leptodactylus exposed to textile wastewater (TW) treated by indigenous white rot fungus Coriolus versicolor. Glutathione S-transferase (GST), cytochrome P450 1A1 (CYP1A1), and acetylcholinesterase (AchE) levels in hepatopancreas and abdomen tissues of crayfish exposed to untreated, treated, and diluted rates (1/10) in both TW during 24 and 96 h were tested. Physiochemical parameters (electrical conductivity (EC), chemical oxygen demand (COD), pH, and total dissolved solid (TDS)) of TW were determined before and after treatment. Physiochemical parameters of TW decreased after treatment. The GST activity and AchE were generally increased, but CYP1A1 activity was decreased in hepatopancreas tissue of crayfish exposed to different kinds of untreated TW. After treatment by indigenous white rot fungus (C. versicolor), GST and CYP1A1 activities were returned to control values, while AchE activities were increasing further. In this study, only GST and CYP1A1 activities of A. leptodactylus confirmed the efficiency of TW treatment with C. versicolor.

Enhanced decolorization of Solar brilliant red 80 textile dye by an indigenous white rot fungus Schizophyllum commune IBL-06

An indigenously isolated white rot fungus, Schizophyllum commune IBL-06 was used to decolorize Solar brilliant red 80 direct dye in Kirk’s basal salts medium. In initial screening study, the maximum decolorization (84.8%) of Solar brilliant red 80 was achieved in 7days shaking incubation period at pH 4.5 and 30°C. Different physical and nutritional factors including pH, temperature and fungal inoculum density were statistically optimized through Completely Randomized Design (CRD), to enhance the efficiency of S. commune IBL-06 for maximum decolorization of Solar brilliant red 80 dye. The effects of inexpensive carbon and nitrogen sources were also investigated. Percent dye decolorization was determined by a reduction in optical density at the wavelength of maximum absorbance (λmax, 590nm). Under optimum conditions, the S. commune IBL-06 completely decolorized (100%) the Solar brilliant red 80 dye using maltose and ammonium sulfate as inexpensive carbon and nitrogen sources, respectively in 3days. S. commune IBL-06 produced the three major ligninolytic enzymes lignin peroxidase (LiP), manganase peroxidase (MnP) and lacaase (Lac) during the decolorization of Solar brilliant red 80. LiP was the major enzyme (944U/mL) secreted by S. commune IBL-06 along with comparatively lower activities of MnP and Laccase.

Bioremediation Potential of Mixed White Rot Culture of Pleurotus Ostreatus IBL-02 and Coriolus Versicolor IBL-04 for Textile Industry Wastewater

In continuation of our studies on single fungal cultures, this study was aimed to investigate the potential of mixed culture of two indigenous white rot fungi Pleurotus ostreatus IBL-02 and Coriolus versicolor IBL-04 to decolorize and detoxify the dye based textile effluent collected from Sitara Textile Industry (SIT), Faisalabad, Pakistan. Different pHysical and nutritional factors were optimized to enhance the efficiency of mixed culture for SIT effluent color removal. Under optimum conditions, the mixed culture completely decolorized (100%) the effluent in 2 days using glucose and urea as carbon and nitrogen sources, respectively in 30:1 ratio. The mixed culture produced all the three major liginolytic enzymes like lignin peroxidase (LiP), manganase peroxidase (MnP) and lacaase. Mediators of ligninolytic enzymes including varatryl alcohol, ABTS and MnSO4 enhanced effluent decolorization showing variable effects on LiP, MnP and laccase activities. Analysis of the treated and untreated SIT effluent showed that fungal treatment significantly reduced the Chemical Oxygen Demand (COD) and Biochemical Oxygen Demand (BOD) of the effluent.

Production and optimization of ligninolytic enzymes by white rot fungus Schizophyllum commune IBL-06 in solid state medium banana stalks

The present study deals with production of ligninolytic enzymes from an indigenous white rot fungus Schizophyllum commune IBL-06 by using banana stalk as substrate through the process of solid state fermentation. The production process was further improved by optimizing a number of physical parameters such as incubation time, moisture level, pH, temperature, inoculums size and nutritional factors (carbon and nitrogen ratio, mediators and metal ions). By optimization of different parameters, the maximum activities of enzymes synthesized by S. commune IBL-06 were observed as 3745 IU/ml for manganese peroxidase (MnP), 2700 IU/ml for lignins peroxidase (LiP) and 345 IU/ml for laccase after 3 days incubation at рH 4.5 and 35°C temperature with 3 ml inoculum size, 60% moisture content, 20:1 C:N ratio (glucose and ammonium nitrate as carbon and nitrogen supplements), 1ml of 1mM MnSO 4 as mediator, and 1ml of 1mM MgSO 4.7H 2O2. This High activities of ligninolytic enzymes produced by the fungus suggest its potential for commercial scale production of these enzymes for diverse industrial applications.

Hyperproductivity of extracellular enzymes from indigenous white rot fungi (P. chrysosporium IBL-03) by utilizing agro-wastes

An indigenous locally isolated white rot fungal strain Phanerochaete chrysosporium IBL-03was investigated for the hyper-production of ligninolytic enzymes from different agro-industrial wastes including wheat straw, rice straw, banana stalks, corncobs, corn stover, and sugarcane bagasse as substrate material in still culture fermentation technique. Screening experiments were performed at 30oC from 1 to 10 days and maximum enzyme activities were recorded after the 5th day of incubation on banana stalk. P. chrysosporium IBL-03 produced highestactivities of lignin peroxidase (LiP) and manganese peroxidase (MnP) but no laccase activity was detected in any fermented culture media. Production of ligninolytic enzymes was substantially enhanced through the optimization process. When banana stalk at 66.6 % moisture level and pH 4.5 was inoculated with 5mL spore suspension of P. chrysosporium IBL-03 at 35oC in the presence of molasses (1%) as carbon source, ammonium sulfate (0.2%) as nitrogen supplement, (1%) Tween-80 (0.3 mL) as surfactant and mediators (MnSO4 and veratryl alcohol) enhanced the LiP and MnP production up to 1040 and 965 (U/mL), respectively.

Co-metabolic degradation of pyrene by indigenous white-rot fungus Pseudotrametes gibbosa from the northeast China

Pyrene as high molecular weight polycyclic aromatic hydrocarbons (PAHs) is found in most terrestrial environment. However, the biodegradation of pyrene has been limited due to its bioavailability and toxicity. So it is vital to study degradation-capable microorganism and suitable co-substrate. In this study, the indigenous white-rot fungus Pseudotrametes gibbosa isolated from ChangBai Mountain located in northeast China was used to degrade pyrene, and 6 co-substrates were selected as co-metabolic carbon and energy sources. The results showed that P. gibbosa was able to utilize pyrene as sole carbon and energy source. The degradation efficiency achieved 28.33% within 18 days. Meanwhile, co-substrate wheat bran extract could stimulate laccase (Lac) production significantly by P. gibbosa, compared with other co-substrates and control (without co-substrate). In the presence of co-substrates, the biodegradation efficiency of pyrene ranged from 34.23% to 50.64% which was enhanced due to co-metabolism except for salicylic acid (25.91%) and phthalic acid (21.64%).

Biodegradation of agro-wastes by some Nigerian white-rot fungi

Three white-rot fungi: Daedalea elegans, Polyporus giganteus, and Lenzites betulina were screened for their lignin degrading abilities on rice straw, maizecob, sawdust of Terminalia superba, and sugarcane bagasse at different time intervals (30, 60, and 90 days). All the fungi demonstrated varying levels of ligninolytic capability with different degrees of lignin degradation in all the fermented substrates. A significant difference (p<0.05) was observed in the mycelia extension of Daedalea elegans grown on the different agro-industrial wastes. D. elegans gave maximum extension of 4.5 cm on sugarcane bagasse. The highest lignin reduction of 92.9% (p<0.05) was recorded in maize cob fermented with Daedalea elegans after 90 days. On the basis of lignocellulosic material degraded, it is concluded that the white-rot fungi offer a better alternative to conventional ways of disposing these waste substances. This paper considers the ability of indigenous white-rot fungi to degrade lignin as a way of using them in effective waste management.

Laccase mediated decolorization of vat dyes by Coriolus versicolor IBL-04

Five indigenous white rot fungi Pleurotus ostreatus IBL-02, Phanerochaete chrysosporium IBL-03, Coriolus versicolor IBL-04, Ganoderma lucidum IBL-05 and Schizophyllum commune IBL-06 were screened for decolorization of four vat dyes, Cibanon red 2B-MD, Cibanon golden-yellow PK-MD, Cibanon blue GFJ-MD and Indanthrene direct black RBS. The screening experiment was run for 10 days with 0.01% dye solutions prepared in alkaline Kirk's basal nutrient medium in triplicate (250 ml flasks). Every 48 h samples were read on their respective wavelengths ( λ max) to determine the percent decolorization. It was observed that C. versicolor IBL-04 could effectively decolorized all the four vat dyes at varying incubation times but best results were shown on Cibanon blue GFJ-MD (90.7%) after 7 days, followed by golden-yellow (88%), Indanthrene direct black (79.7%) and Cibanon red (74%). P. chrysosporium also showed good decolorization potential on Cibanon blue (87%), followed by Cibanon golden-yellow (74.8%), Red (71%), and Indanthrene direct black (54.6%). However, rest of the strains showed poor decolorization potential on four vat dyes. C. versicolor showing maximum decolorization of Cibanon blue GFJ-MD was, therefore, selected for process optimization. The effect of varying pH, temperature, initial dye concentration and addition of carbon and nitrogen sources was investigated. Maximum decolorization (98.5%) of 0.01% Cibanon blue GFJ-MD could be achieved after 3 days at pH 5 and 30 °C temperature in the nutrient medium supplemented with 1% starch as additional carbon source. All the supplementary nitrogen sources were found inhibitory to laccase activity and dye decolorization. It was also noted that there was negligible adsorption of the dye on fungal mycelia and laccase catalyzed biodegradation was the major decolorization route.

Bioremediation of Engine Oil Polluted Soil by the Tropical White Rot Fungus,Lentinus squarrosulus Mont. (Singer)

This study was conducted to test the efficacy of an indigenous white rot fungus Lentinus squarrosulus in degrading engine oil in soil. Flasks containing sterilized garden soil (100 g) moistened with 75% distilled water (w/v) were contaminated with engine oil 1, 2.5, 5, 10, 20 and 40% w/w concentrations, inoculated with L. squarrosulus and incubated at room temperature for 90 days. Levels of organic matter, pH, total hydrocarbon and elemental content (C, Cu, Fe, K, N, Ni, Zn and available P) were determined post-fungal treatment. Results indicate that contaminated soils inoculated with L. squarrosulus had increased organic matter, carbon and available phosphorus, while the nitrogen and available potassium was reduced. A relatively high percentage degradation of Total Petroleum Hydrocarbon (TPH) was observed at 1% engine oil concentration (94.46%), which decreased to 64.05% TPH degradation at 40% engine oil contaminated soil after 90 days of incubation. The concentrations of Fe, Cu, Zn and Ni recovered from straw/fungal biomass complex increased with the increase of engine-oil contamination and bio-accumulation by the white-rot fungus. The improvement of nutrient content values as well as the bioaccumulation of heavy metals at all levels of engine oil concentrations tested through inoculations with L. squarrosulus is of importance for the bioremediation of engine-oil polluted soils.

Bioremedial Degradation of Some Herbicides by Indigenous White Rot Fungus, Lentinus subnudus

Bioremedial Degradation of Some Herbicides by Indigenous White Rot Fungus, Lentinus subnudus

Bioremediation of oil-polluted soil by Lentinus subnudus , a Nigerian white-rot fungus

Inspite of the realization and studies on the use of microorganisms in degrading hydrocarbons there has been very little work on indigenous white-rot fungi in Nigeria, a leading oil – producing country. the ability of Lentinus subnudus to mineralize soil contaminated with various concentrations of crude oil was tested. Organic matter and carbon were higher than the control at all concentrations of crude oil contamination in soils inoculated with L. subnudus for 3 months. Nutrient contents were generally higher after 6 months of incubations except potassium levels which were not significantly different from the control. As for the total petroleum hydrocarbon (tph) in crude – oil contaminated soils; the highest rate of biodegradation was at 20% concentration after 3 months and 40% after 6 months of incubation. Key words : bioremediation, crude oil, total petroleum hydrocarbon oil-polluted soil, Lentinus subnudus African Journal of Biotechnology Vol. 4 (8), pp. 796-798

Bioremediation of oil-polluted soil by Lentinus subnudus, a Nigerian white-rot fungus

Inspite of the realization and studies on the use of microorganisms in degrading hydrocarbons there has been very little work on indigenous white-rot fungi inNigeria, a leading oil – producing country. the ability of Lentinus subnudus to mineralize soil contaminated with various concentrations of crude oil was tested. Organic matter and carbon were higher than the control at all concentrations of crude oil contamination in soils inoculated with L. subnudus for 3 months. Nutrient contents were generally higher after 6 months of incubations except potassium levels which were not significantly different from the control. AS for the total petroleum hydrocarbon (tph) in crude – oil contaminated soils; the highest rate of biodegradation was at 20% concentration after 3 months and 40% after 6 months of incubation. Key words: Bioremediation, crude oil, total petroleum hydrocarbon oil-polluted soil,Lentinus subnudus.