Perenniporia Tephropora Research Articles

Decolorization of Textile Dyes by Extracellular Enzymes Produced from Trametes sanguinea and Perenniporia taephropora Immobilized on Natural Media

The color of textile wastewater is still a main problem in wastewater treatment by biological processes. The colored effluents from textile factories usually exceed effluent standards. Therefore, various innovations were developed to treat textile wastewater for decolorization in the effluents. This research aims to decolorize textile wastewater by immobilizing white rot fungi degradation. At first, the 11 fungal stains were tested to find the decolorized efficiency then the high decolorized efficiency fungal stains were immobilized on four material media, namely water hyacinth stalks, coconut husk, corn cob, and loofah. After that, the immobilized fungi were cultivated in the culture media at 30, 60, and 120 C/N ratios, respectively. The results showed that Trametes sanguinea and Perenniporia tephropora were two stains with a high decolorized efficiency of 68.8% and 67.5% respectively, and the decolorized efficiency was increased when immobilized on loofahs and fed with 120 C/N ratio medium. In a comparison of two fungal stains, P. tephropora was found more suitable for the decolorization of textile wastewater than T. sanguinea because T. sanguinea could produce red-orange pigments that induced the colored enhancement in wastewater over time. Finally, immobilized P. tephropora was cultivated in a 120 C/N ratio medium within a 10 L continuous stirred tank reactor (8 L working volume) to investigate the decolorized efficiency, enzymatic activity, and repeated batch. It was found that three repeated cycles were carried out by reusing the immobilized P. tephropora and the highest decolorized efficiency was 63.4%. The enzymatic activity of laccase, manganese peroxidase, and lignin peroxidase was 15.5 U/L, 85.9 U/L, and 0 U/L, respectively

1H-Pyrrole-2,5-dicarboxylic acid, a quorum sensing inhibitor from one endophytic fungus in Areca catechu L., acts as antibiotic accelerant against Pseudomonas aeruginosa.

Pseudomonas aeruginosa has already been stipulated as a "critical" pathogen, emphasizing the urgent need for researching and developing novel antibacterial agents due to multidrug resistance. Bacterial biofilm formation facilitates cystic fibrosis development and restricts the antibacterial potential of many current antibiotics. The capacity of P. aeruginosa to form biofilms and resist antibiotics is closely correlated with quorum sensing (QS). Bacterial QS is being contemplated as a promising target for developing novel antibacterial agents. QS inhibitors are a promising strategy for treating chronic infections. This study reported that the active compound PT22 (1H-pyrrole-2,5-dicarboxylic acid) isolated from Perenniporia tephropora FF2, one endophytic fungus from Areca catechu L., presents QS inhibitory activity against P. aeruginosa. Combined with gentamycin or piperacillin, PT22 functions as a novel antibiotic accelerant against P. aeruginosa. PT22 (0.50 mg/mL, 0.75 mg/mL, and 1.00 mg/mL) reduces the production of QS-related virulence factors, such as pyocyanin and rhamnolipid, and inhibits biofilm formation of P. aeruginosa PAO1 instead of affecting its growth. The architectural disruption of the biofilms was confirmed by visualization through scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). Real-time quantitative PCR (RT-qPCR) indicated that PT22 significantly attenuated the expression of QS-related genes followed by docking analysis of molecules against QS activator proteins. PT22 dramatically increased the survival rate of Galleria mellonella. PT22 combined with gentamycin or piperacillin presents significant inhibition of biofilm formation and eradication of mature biofilm compared to monotherapy, which was also confirmed by visualization through SEM and CLSM. After being treated with PT22 combined with gentamycin or piperacillin, the survival rates of G. mellonella were significantly increased compared to those of monotherapy. PT22 significantly enhanced the susceptibility of gentamycin and piperacillin against P. aeruginosa PAO1. Our results suggest that PT22 from P. tephropora FF2 as a potent QS inhibitor is a candidate antibiotic accelerant to combat the antibiotic resistance of P. aeruginosa.

Identification of oil palm tissue culture contaminants by using DNA barcodes: preliminary results

The success of oil palm tissue culture is constrained by the microbes contaminating cultures in the laboratory. Accurate identification of contaminant species leads to the right strategies for solving the contamination problem. This research was done to identify contaminant species at the Indonesian Oil Palm Research Institute Tissue Culture Laboratory at its stages by using DNA barcodes. Bacteria identification was done by 16S rRNA sequencing, while fungi identification was done by ITS region sequencing. Preliminary results showed that bacteria and fungi were identified in the laboratory’s stages of the tissue culture process. Four species were identified in the dark room, two in the light room, and four in the advanced light room. The identified bacteria were Bacillus subtilis, Streptococcus parasuis, Priestia megaterium, and Bacillus sp. The identified fungi were Tritirachium candoliense, Penicillium citrinum, Irpex laceratus, Aspergillus reticulatus, and Perenniporia tephropora. More data is needed to determine the right strategies to control the contamination problem.

Characterization of white rot fungi from wood decayed for lignin degradation.

The present study was conducted to isolate and identify white rot fungi (WRF) from wood decayed and to determine their ability to produce lignin-modifying enzymes (LMEs), specifically laccase (Lac), lignin peroxidase (LiP), and manganese peroxidase (MnP), on solid and liquid media supplemented with synthetic dyes namely 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), azure B, and phenol red. A total of 23 isolates of WRF were isolated from decayed wood and identified as eight different species namely Phanerochaete australis, Perenniporia tephropora, Lentinus squarrosulus, Ganoderma australe, Trametes polyzona, Lentinus sajor-caju, Gymnopilus dilepis, and Fomitopsis palustris based on morphological characteristics, DNA sequences of the internal transcribed spacer (ITS) region, and phylogenetic inference. The fungal isolates can be divided into four groups based on the type of LMEs produced, namely A (Lac-LiP-MnP) with 16 isolates, B (Lac-MnP) (three isolates), C (Lac) (three isolates), and D (MnP) (one isolate). This study highlights P. australis (BJ38) as the best producer of Lac and LiP, while L. squarrosulus (IPS72) is the best producer of MnP. The present study is the first reported P. australis as an efficient lignin degrader by demonstrating the highest activity of two important LMEs.

DIVERSITY OF ENDOPHYTIC FUNGI ASSOCIATED WITH FRUITS AND LEAVES OF TAMARIND (Tamarindusindica L.) BASED O N ITS RIBOSOMAL DNA SEQUENCES

Plant-associated microbes are among the important natural resources that abundantly exist in natural environment such as endophytic fungi. The studies on endophytic fungi in medicinal plants have allowed the discovery of numerous fungi species and their hidden potentials. Therefore, this study focused on the isolation and identification of endophytic fungi from several plant parts of tamarind such as leaves and fruits. A total of 69 fungal cultures were successfully isolated and identified into 33 distinct species from 14 genera based on morphological characteristics and internal transcribed spacer (ITS) sequence analysis using a Maximum Likelihood method. There were six different species obtained from the genus Colletotrichum (C. aenigma, C. brevisporum, C. cobbittiense, C. fructicola, C. gloeosporioides and C. siamense), and Diaporthe (D. arecae, D. ceratozamiae, D. phaseolorum, D. pseudomangiferae, D. pseudooculi and D. pseudophoenicicola), four species of Aspergillus (A. aculeatus, A. carbonarius, A. flavus and A. tubingensis), three species of Curvularia (C. aeria , C. geniculata and C. lunata) and Nigrospora (N. lacticolonia, N. oryzae and N. sphaerica), two species of Lasiodiplodia (L. pseudotheobromae and L. theobromae) and Penicillium (P. rolfsii and P. verruculosum). Other fungal species that were also identified are Botryosphaeria mamane, Fusarium solani, Perenniporia tephropora, Phyllosticta fallopiae, Sarcostroma bisetulatum, Trichoderma asperellum and Xylaria feejeensis. The isolates were grouped into different clades according to their class. In conclusion, endophytic fungi isolated from tamarind plant are diverse and provides an insight into species diversity of endophytic fungi in tamarind.

Bioactive compounds from the bark of Broussonetia papyrifera after solid fermentation with a white rot fungus Perenniporia tephropora

In this study, potential bioactive compounds in the products of the solid fermentation of the paper mulberry tree bark (Broussonetia papyrifera) with a white rot fungus (Perenniporia tephropora) were investigated. Fractionation of methanolic extracts from the fermented products of the bark led to the isolation of 10 known compounds, namely broussonin B (1), broussonin A (2), 7,4'-dihydroxy-3'-prenylflavan (3), cathayanon H (4), broussoflavonol B (5), isoliquiritigenin (6), broussochalcone B (7), glyasperin A (8), marmesin (9), and vomifoliol (10). Their structures were determined by spectroscopic analysis (including considerations of MS, 1H, 13C NMR, COSY, HMQC, and HMBC spectra) and compared with structures that had been published in the literature. Of these compounds identified, cathayanon H (4) and glyasperin A (8) were isolated for the first time from the paper mulberry tree. Vomifoliol (10) was produced from the bark only after fermentation with white rot fungi. It was observed that concentrations of marmesin (9) and vomifoliol (10) generally increased with an increase in fermentation time, whereas concentration of compounds 1‒8 in the fermented products decreased during the same period. Biological tests showed that the tyrosinase inhibitory activity of marmesin (9) (IC50 = 168.0 μM) was similar to that of arbutin, a well-known tyrosinase inhibitor, whereas vomifoliol (10) exhibited no tyrosinase inhibition activity at any concentration higher than 2 mM. Accordingly, both solids and the liquid broth left after fermentation of the paper mulberry tree bark with the aforementioned white rot fungus could be developed for potential use in industrial applications.

An approach to quantify natural durability of Eucalyptus bosistoana by near infrared spectroscopy for genetic selection

Natural durability within a timber species can be variable. Hence efficient assessments of natural durability are required to ensure quality either through tree breeding or segregation during production. In this study, first the relationship between extractive content and mass loss of Eucalyptus bosistoana heartwood caused by a white and a brown-rot fungus was validated. Then the ability of NIR spectroscopy as a high-throughput method to evaluate heartwood decay resistance was examined. Finally the NIR method was applied to a tree breeding trial. A correlation between extractive content and mass loss against the white-rot fungus (Perenniporia tephropora) and the brown-rot fungus (Coniophora olivacea) were found. Analysis of NIR spectra indicated that this relationship is causal with shared bands for mass loss and extractive content models at 6650, 6017, 5265 and 4659 cm−1. Partial least squares regression (PLSR), supplemented with spectra normalisation and variable selection, allowed prediction of mass loss with a residual mean square error (RMSE) of 7.48 % and 5.76 % for the white-rot and brown-rot, respectively. This level of precision allowed the characterisation of a E. bosistoana resource which showed a range of mass loss from 0 to 60 %. Genetic control was found for mass loss by the white-rot ( h2 = 0.70 and 0.24) and the brown-rot ( h2 = 0.15 and 0.13) at two sites in New Zealand. The rankings were correlated between sites, with genetic correlations (Rg2) of 0.69 and 0.63 for white-rot and brown-rot, respectively, as well as to the predicted extractive content (0.82 to 0.92). However, the study indicated a significant site effect on the decay resistance of the E. bosistoana heartwood. In summary, this study has shown that the decay resistance could be assessed rapidly and efficiently using NIR technology for genetic selection.

Phylogenetic study of endophytic fungi associated with Centella asiatica from Bengkulu and Malaysian accessions based on the ITS rDNA sequence

Abstract. Radiastuti N, Bahalwan HA, Susilowati DN. 2019. Phylogenetic study of endophytic fungi associated with Centella asiatica from Bengkulu and Malaysian accessions based on the ITS rDNA sequence. Biodiversitas 20: 1248-1258. Centella asiatica is one of the medicinal plants which is known to be symbiotic with various endophytic fungi. The purpose of this research was to determine diversity of culturable fungal endophyte from C. asiatica. Identification was conducted using molecular phylogenetic analysis based on the ITS rDNA sequence. The result showed that obtained 145 isolates endophytic fungi (from stolons, leaves, roots, petioles) were grouped into 18 morphotaxa (Bengkulu) and 23 morphotaxa (Malaysian). The fungal endophytic were identified as Aspergillus austroafricanus, Aspergillus oryzae, Acrocalymma vagum, Ceratobasidium cornigerum, Ceratobasidium sp., Chaetomium globosum, Colletotrichum karstii, C. gigasporium, C. tabaci, Colletotrichum siamense, Eutypella sp., Fusarium solani, F. oxysporum, F. falciforme, F. keratoplasticum, F. striatum, Fusarium sp., Penicillium capsulatum, Phoma multirostrata, Perenniporia tephropora, Perenniporia sp., Phanerochaete chrysosporium, Phanerochaete stereoides, Phyllosticta capitalensis, Phomopsis asparagi, Peroneutypa scoparia, Phialemoniopsis sp., Mycochaetophora gentinae, Talaromyces sp., Earliella scabrosa, and Trichaptum sp. based on molecular phylogenetic analysis. Fusarium (Nectriaceae) were the most found of fungal endophytes in both C. asiatica Bengkulu and Malaysian accession. The majority strain are including Ascomycetes and Basidiomycetes. The identification of endophytic fungi from medicinal plants is needed as a preliminary study to determine the potential of endophytic fungi producing bioactive compounds.

Physiological Regulation of an Alkaline-Resistant Laccase Produced by Perenniporia tephropora and Efficiency in Biotreatment of Pulp Mill Effluent

Regulation of alkaline-resistant laccase from Perenniporia tephropora KU-Alk4 was proved to be controlled by several factors. One important factor was the initial pH, which drove the fungus to produce different kinds of ligninolytic enzymes. P. tephropora KU-Alk4 could grow at pH 4.5, 7.0, and 8.0. The fungus produced laccase and MnP at pH 7.0, but only laccase at pH 8.0. The specific activity of laccase in the pH 8.0 culture was higher than that in the pH 7.0 culture. At pH 8.0, glucose was the best carbon source for laccase production but growth was better with lactose. Low concentrations of glucose at 0.1% to 1.0% enhanced laccase production, while concentrations over 1% gave contradictory results. Veratryl alcohol induced the production of laccase. A trace concentration of copper ions was required for laccase production. Biomass increased with an increasing rate of aeration of shaking flasks from 100 to 140 rpm; however, shaking at over 120 rpm decreased laccase quantity. Highest amount of laccase produced by KU-Alk4, 360 U/mL, was at pH 8.0 with 1% glucose and 0.2 mM copper sulfate, unshaken for the first 3 days, followed by addition of 0.85 mM veratryl alcohol and shaking at 120 rpm. The crude enzyme was significantly stable in alkaline pH 8.0~10.0 for 24 hr. After treating the pulp mill effluent with the KU-Alk4 system for 3 days, pH decreased from 9.6 to 6.8, with reduction of color and chemical oxygen demand at 83.2% and 81%, respectively. Laccase was detectable during the biotreatment process.

Determining the Pathogenic Potential of Non-sporulating Molds Isolated from Cutaneous Specimens.

Although non-sporulating molds (NSM) are frequently isolated from patients and have been recognized as agents of pulmonary disease, their clinical significance in cutaneous specimens is relatively unknown. Therefore, this study aimed to identify NSM and to determine the keratinolytic activity of isolates from cutaneous sites. NSM isolates from clinical specimens such as skin, nail, and body fluids were identified based on their ribosomal DNA sequences. Of 17 NSM isolates (7 Ascomycota, 10 Basidiomycota), eleven were identified to species level while five were identified to the genus level. These include Schizophyllum commune, a known human pathogen, Phoma multirostrata, a plant pathogen, and Perenniporia tephropora, a saprophyte. To determine fungal pathogenicity, keratinolytic activity, a major virulence factor, was evaluated ex vivo using human nail samples by measuring dye release from keratin azure, for NSM along with pathogens (Trichophyton mentagrophytes, Trichophyton rubrum, Microsporum canis and Fusarium spp.) and nonpathogenic (endophyte) fungi for comparison. This study showed that pathogenic fungi had the highest keratinolytic activity (7.13±0.552 keratinase units) while the nonpathogenic endophytes had the lowest activity (2.37±0.262 keratinase units). Keratinolytic activity of two Ascomycota NSM (Guignardia mangiferae and Hypoxylon sp.) and one Basidiomycota NSM (Fomitopsis cf. meliae) was equivalent to that of pathogenic fungi, while Xylaria feejeensis showed significantly higher activity (p<0.05) than nonpathogenic endophytes. These results indicate that the pathogenic ability of NSM is species dependent; clinical isolates, especially more frequently isolated species, may be involved in disease etiology.

Cytotoxic metabolites from Perenniporia tephropora, an endophytic fungus from Taxus chinensis var. mairei

Based on bioactivity-oriented isolation, the EtOAc extract of a culture broth of the endophytic fungus Perenniporia tephropora Z41 from Taxus chinensis var. mairei, with strong anti-Pyricularia oryzae activity, afforded a new sesquiterpenoid, perenniporin A (1), together with three known compounds, ergosterol (2), rel-(+)-(2aR,5R,5aR,8S,8aS,8bR)-decahydro-2,2,5,8-tetramethyl-2H-naphtho[1,8-bc]genfuran-5-ol (3), and albicanol (4). Their structures were elucidated by means of spectroscopic methods. All the isolated compounds and the EtOAc extract of P. tephropora Z41 (EPT) were evaluated for their cytotoxic activity against three human cancer cell lines (HeLa, SMMC-7721, and PANC-1). EPT demonstrated significant cytotoxicity with IC(50) values ranging from 2 to 15μg/mL. Compound 2 was the most cytotoxic constituent against the tested cell lines with IC(50) values of 1.16, 11.63, and 11.80μg/mL, respectively, while compounds 1, 3, and 4 exhibited moderate cytotoxicity with IC(50) values ranging from 6 to 58μg/mL. We conclude that the endophytic fungus P. tephropora is a promising source of novel and cytotoxic metabolites.

English

&nbsp; Nineteen strains of wood-inhabiting pores fungi, representing thirteen species and ten genera, collected from both natural and &ldquo;anthropic&rdquo; (urban) ecosystems in Cuba were tested for their ability to decolourise the industrial anthraquinonic dye Acid Blue 62 (AB 62) in laboratory conditions, in both solid and liquid media. On the basis of their decolourisation rate and growth inhibition, seven strains viz.Tinctoporellus epimiltinus, Trametes maxima,&nbsp;Perenniporia tephropora,Coriolopsis rigida,&nbsp;Hexagonia tenuis,&nbsp;Pachykytospora alabamae&nbsp;and&nbsp;Hexagonia hydnoides&nbsp;were selected for further studies.&nbsp;All the strains were able to decolourise partially or completely the AB62 dye added to Malt extract. Almost total decolourisation was obtained with&nbsp;T. maxima.&nbsp;Decolourising activity was also shown with an industrial textile effluent, containing Remazol Yellow RGB, Remazol Red RR, and Remazol Black B 133. Production of laccase, a ligninolytic enzyme possibly involved in decolourisation, was stimulated by AB 62 for all the strains tested;&nbsp;T.&nbsp;maxima&nbsp;showing the highest production. Lignin peroxidase and manganese peroxidase were not produced under the experimental conditions used.&nbsp;T. maxima&nbsp;could represent a potential candidate for biotechnological applications. The exploitation of local biodiversity in tropical area appears as a potentially productive approach for identifying promising microbial strains for industrial use. &nbsp; Key words:&nbsp;Anthraquinones, dyes, bioremediation, decolourisation, laccase, textile effluent,&nbsp;Trametes maxima, white rot fungi, Acid Blue 62. &nbsp;

Coupling occurs before breakdown during biotransformation of Acid Blue 62 by white rot fungi

Only few data exist on the metabolites produced during the biotransformation of anthraquinonic dyes by white rot fungi (WRF). During the biotransformation of an anthraquinonic dye Acid Blue 62 (ABu62) using Pycnoporus sanguineus MUCL 41582 strain, it was previously demonstrated that the blue colour of the medium turned to red before complete dye decolourisation. To better understand the phenomenon, this study carried out ABu62 biotransformation with five different WRF strains ( Coriolopsis polyzona MUCL 38443, Perenniporia ochroleuca MUCL 41114, Perenniporia tephropora MUCL 41562, P. sanguineus MUCL 38531 and Trametes versicolor MUCL 38412) and compared with P. sanguineus MUCL 41582 previously described. A multi-methodological approach (using capillary electrophoresis, mass spectrometry, HPLC, UV, NMR and IR spectroscopies) was developed to characterise the metabolites involved and monitor their apparition. Seven metabolites were commonly found with all strains, suggesting a common metabolic pathway for ABu62 biotransformation. During the first days, dimer and oligomers of the initial ABu62 molecule were observed: the main one absorbed in the 500 nm region, explaining the red colour appearance of the medium. This main metabolite was made up of two molecules of ABu62 linked by an azo bond, minus a cyclohexyl moiety. After a longer incubation time, breakdown products were observed. Based on these products characterizations, a bioconversion pathway was proposed.

Cytotoxicity and genotoxicity evolution during decolorization of dyes by White Rot Fungi

White Rot Fungi (WRF) are able to decolorize dyes through the use of relatively non-specific extracellular oxidative enzymes. Nevertheless, decolorization does not imply that the resulting metabolites are less toxic than the parent molecules. The aim of the present study was to evaluate the detoxification potential of six strains (Pycnoporus sanguineus, Perenniporia tephropora, Perenniporia ochroleuca, Trametes versicolor, Coriolopsis polyzona and Clitocybula dusenii) during decolorization of dyes. Cytotoxicity assays were carried out on human Caco-2 cells, which are considered as a validated model for the human intestinal epithelium, and the results were compared with those obtained on classical bacterial cells. Genotoxic character was monitored through VITOTOX® assays. The biotransformation of an anthraquinonic dye (CI Acid Blue 62, ABu62) was studied. All tested strains were able to decolorize extensively ABu62 (between 83 and 95% decolorization), however, different cytotoxicity reduction levels were reached (from 44 to 99%). Best results were achieved with P. sanguineus strain and the major role of laccases in cytotoxicity reduction was underlined. Based on this result, efficiency of P. sanguineus strain was further studied. Four azo and two anthraquinonic dyes were treated by this strain. After WRF treatment, two dyes were found to be more toxic in one or both toxicity assays. Genotoxic character appeared during biotransformation of one dye, however, it was removed by the addition of hepatic rat extract to mimic liver transformation. These results stress the importance of monitoring several parameters, such as colour, toxicity and mutagenicity, to ensure the efficiency of the bioremediation process.

Biodeterioration of treated Pinus radiata timber by Australian decay fungi and the termite Coptotermes acinaciformis in laboratory bioassays and field conditions

Abstract The resistance of Pinus radiata sapwood blocks treated with a boron-based preservative to biodeterioration by five Australian wood destroying fungi [Fomitopsis lilacino-gilva, Coniophora olivacea, Gloeophyllum abietinum (boron resistant), Serpula lacrymans and Perenniporia tephropora] was investigated. A phenyl pyrazole termiticide (fipronil) was also incorporated into the formulation to determine whether its presence affects biological efficacy. A linseed oil, liquid wax, terebene and trimethyl borate formulation inhibited decay by the trial fungi. Incorporation of fipronil did not affect the fungicidal properties. Fipronil alone exhibited no fungicidal activity. The termiticidal activity of fipronil was assessed (termite field test) in a formulation incorporating a fungicide, water repellent and drying agent in an alternative solvent carrier to that previously reported. The biological activity of the test compound was not diminished in this system. The 1-year progress performance of an ongoing in ground graveyard trial of similarly treated stakes, exposed to numerous termite species and decay fungi in tropical field conditions, is also presented. The predominant biological agent at the field site is the Australian subterranean termite Coptotermes acinaciformis (Froggatt). Treated stake samples of the Australian softwood Pinus radiata were exposed.

Purification and characterization of the laccase secreted by the white rot fungus Perenniporia tephropora and its role in the decolourization of synthetic dyes

To characterize the white rot fungus Perenniporia tephropora with respect to its laccase and to test its ability to decolourize synthetic dyes. Under the culture conditions utilized, P. tephropora produced one laccase isozyme, which was purified to electrophoretic homogeneity by ammonium sulfate precipitation, size-exclusion chromatography and anion-exchange chromatography. The protein was monomeric with a molecular mass of 63 kDa (SDS-PAGE) and had an isoelectric point of 3.3. The N-terminal amino acid sequence was SIGPVADLTVTNANI and the highest similarity value was found to the laccase from Lentinus tigrinus (86.6%). The optimum pH of the enzyme varied and was substrate dependent. It was 4.0 and 5.0 for 2,6-dimethoxyphenol (DMP) and 2,2'-azino-di(3-ethyl-benzthiazoline-6-sulfonate) (ABTS), respectively. Under standard assay conditions, K(m) values of the enzyme were 7.3 and 0.4 mmol l(-1) towards DMP and ABTS, respectively. The laccase was inhibited by NaN(3), EDTA and p-coumarate but not by SDS and NaBr. Laccase was stable in the presence of some metal ions such as Cu(2+), Co(2+), Ca(2+), Cd(2+), Mg(2+), Mn(2+), Mo(2+), Ni(2+), Li(+) and Al(3+). The crude enzyme as well as the purified laccase was able to decolourize dyes from the textile industries, including remazol brilliant blue R, neolane blue and neolane pink. However, several other dyes were partially or not decolourized. In the presence of 1-hydroxybenzotriazole as mediator, only the decolourization of neolane yellow was achieved, while the decolourization of most of the dyes was just slightly improved. This study is the first report on the purification and the characterization of the laccase from the white rot fungus P. tephropora. The high levels of laccase secreted by this fungal strain as well as its stability suggest that it could be a useful tool for environmental applications.

The Aphyllophorales of Mungyong Saejae

To evaluate the establishment of Mungyong Saejae Natural Ecology Park located in the northwestern Gyongbuk Province, a scientific survey for the mushroom flora of the park was carried out from May to December of 1999. A checklist of the Aphyllophorales collected from the park was prepared. The list included 67 species of 44 genera belonging to nine families in the Aphyllophorales. Among them, seven species, Antrodia malicola, Ceriporia purpurea, Oligoporus leucospongia, Perenniporia tephropora, Phanerochaete xerophila, Sistotrema diademiferum and Vuilleminia comedens, were confirmed as new to Korea and are registered here as unrecorded species along with descriptions and microscopic drawings.

Extracellular oxidases and the transformation of solubilised low-rank coal by wood-rot fungi

The involvement of extracellular oxidases in biotransformation of low-rank coal was assessed by correlating the ability of nine white-rot and brown-rot fungi to alter macromolecular material in alkali-solubilised brown coal with the spectrum of oxidases they produce when grown on low-nitrogen medium. The coal fraction used was that soluble at 3.0?pH?6.0 (SWC6 coal). In 15-ml cultures, Gloeophyllum trabeum, Lentinus lepideus and Trametes versicolor produced little or no lignin peroxidase, manganese (Mn) peroxidase or laccase activity and caused no change to SWC6 coal. Ganoderma applanatum and Pycnoporus cinnabarinus also produced no detectable lignin or Mn peroxidases or laccase yet increased the absorbance at 400 nm of SWC6 coal. G. applanatum, which produced veratryl alcohol oxidase, also increased the modal apparent molecular mass. SWC6 coal exposed to Merulius tremellosus and Perenniporia tephropora, which secreted Mn peroxidases and laccase and Phanerochaete chrysosporium, which produced Mn and lignin peroxidases was polymerised but had unchanged or decreased absorbance. In the case of both P. chrysosporium and M. tremellosus, polymerisation of SWC6 coal was most extensive, leading to the formation of a complex insoluble in 100 mM NaOH. Rigidoporus ulmarius, which produced only laccase, both polymerised and reduced the A 400 of SWC6 coal. P. chrysosporium, M. tremellosus and P. tephropora grown in 10-ml cultures produced a spectrum of oxidases similar to that in 15-ml cultures but, in each case, caused more extensive loss of A 400, and P. chrysosporium depolymerised SWC6 coal. It is concluded that the extracellular oxidases of white-rot fungi can transform low-rank coal macromolecules and that increased oxygen availability in the shallower 10-ml cultures favours catabolism over polymerisation.

Solubilization of Australian lignites by fungi and other microorganisms

Lignites from the Latrobe Valley in Victoria are solubilized by Coriolus versicolor, Phanerochaete chrysosporium, and five other species known to be active on Leonardite and various acid-treated North American lignites. Run-of-mine coal from Morwell and Loy Yang is refractory but is soluble after pretreatment with acid. A weathered deposit at Loy Yang, like Leonardite, is susceptible to biosolubilization without pretreatment. The white rot fungi Ganoderma applanatum, Perenniporia tephropora (Fomes lividus), Pleurotus ostreatus, Pycnoporus cinnabarinus, Rigidoporus ulmarius, and Xylaria hypoxylon were found to be capable of solubilizing lignite. In contrast, brown rot fungi were weakly active or inactive under the same test conditions. Lignite-degrading fungi, actinomycetes, and other bacteria, including some active on untreated run-of-mine coal, were isolated from natural lignite exposures and minning sites

Progressive changes in cell wall components of Pinus radiata during decay

Progressive changes in solubility characteristics and lignin content of Pinus radiata sapwood were assessed when small blocks were subjected to decay by brown ( Gloeophyllum trabeum) and white ( Perenniporia tephropora) rot fungi. The brown rot species removed lignin in approximate proportion to weight loss up to 10%; thereafter the amount of lignin altered little. In contrast, the decline in lignin content was near linear for P. tephropora. Increases in solubility (particularly with hot water and dilute alkali), in sugar content and in the acidity of aqueous extracts were recorded in wood blocks decayed to 15–20% weight loss. While these effects were more pronounced in samples decayed by G. trabeum, it appears that with both organisms structural components were degraded faster than the products could be utilised. In this case, cell wall chemistry may not have been a major determinant of weight losses.