Diversity of the Bambusicolous Fungus Apiospora in Korea: Discovery of New Apiospora Species.

Many Apiospora species have been isolated from bamboo plants - to date, 34 bambusicolous Apiospora species have been recorded. They are known as saprophytes, endophytes, and plant pathogens. In this study, 242 bambusicolous Apiospora were isolated from various bamboo materials (branches, culms, leaves, roots, and shoots) and examined using DNA sequence similarity based on the internal transcribed spacer, 28S large subunit ribosomal RNA gene, translation elongation factor 1-alpha, and beta-tubulin regions. Nine Apiospora species (Ap. arundinis, Ap. camelliae-sinensis, Ap. hysterina, Ap. lageniformis sp. nov., Ap. paraphaeosperma, Ap. pseudohyphopodii sp. nov., Ap. rasikravindrae, Ap. saccharicola, and Ap. sargassi) were identified via molecular analysis. Moreover, the highest diversity of Apiospora was found in culms, and the most abundant species was Ap. arundinis. Among the nine Apiospora species, two (Ap. hysterina and Ap. paraphaeosperma) were unrecorded in Korea, and the other two species (Ap. lageniformis sp. nov. and Ap. pseudohyphopodii sp. nov.) were potentially novel species. Here, we describe the diversity of bambusicolous Apiospora species in bamboo organs, construct a multi-locus phylogenetic tree, and delineate morphological features of new bambusicolous Apiospora in Korea.

The genus Arthrinium (Ascomycota, Sordariomycetes, Apiosporaceae) from marine habitats from Korea, with eight new species.

Species of Arthrinium are well-known plant pathogens, endophytes, or saprobes found in various terrestrial habitats. Although several species have been isolated from marine environments and their remarkable biological activities have been reported, marine Arthrinium species remain poorly understood. In this study, the diversity of this group was evaluated based on material from Korea, using morphological characterization and molecular analyses with the internal transcribed spacer (ITS) region, ß-tubulin (TUB), and translation elongation factor 1-alpha (TEF). A total of 41 Arthrinium strains were isolated from eight coastal sites which represented 14 species. Eight of these are described as new to science with detailed descriptions.

Genomic Analysis and Assessment of Melanin Synthesis in Amorphotheca resinae KUC3009.

This study reports the draft genome of Amorphotheca resinae KUC30009, a fungal isolate with promising industrial-scale melanin production potential. The mechanisms for melanin or melanin-related pigment formation of this strain were examined through bioinformatic and biochemical strategies. The 30.11 Mb genome of A. resinae contains 9638 predicted genes. Genomic-based discovery analyses identified 14 biosynthetic gene clusters (BGCs) associated with secondary metabolite production. Moreover, genes encoding a specific type 1 polyketide synthase and 4-hydroxynaphthalene reductase were identified and predicted to produce intermediate metabolites of dihydroxy naphthalene (DHN)-melanin biosynthesis pathway, but not to DHN-melanin. These findings were further supported by the detection of increased flaviolin concentrations in mycelia and almost unchanged morphologies of the culture grown with tricyclazole. Apart from this, the formation of melanin in the culture filtrate appeared to depend on the laccase-like activity of multi-copper oxidases. Simultaneously, concentrations of nitrogen-containing sources decreased when the melanin formed in the media. Interestingly, melanin formation in the culture fluid was proportional to laccase-like activity. Based on these findings, we proposed novel strategies for the enhancement of melanin production in culture filtrates. Therefore, our study established a theoretical and methodological basis for synthesizing pigments from fungal isolates using genomic- and biochemical-based approaches.

Utilization of extracellular fungal melanin as an eco-friendly biosorbent for treatment of metal-contaminated effluents.

Fungal melanins have been considered as potential biosorbents due to their metal-binding properties, stability, and scalability. Previous studies established scalable fungal melanin production methods with promising strains, however, their applicability for metal-contaminated effluents treatment has not been sufficiently reported. Herein, melanin pigment derived from Amorphotheca resinae was produced and characterized using microscopy and spectroscopy techniques. Adsorptive properties towards Cu(II), Pb(II), Cd(II), and Zn(II) were evaluated using batch tests. Melanin pigment was composed of aggregates of nanosized particles with indole-based constituents. Adsorption capacities increased with the pH of solution, especially at pH > 4.0. Maximum binding capacities of Cu(II), Pb(II), Cd(II), and Zn(II) on melanin were 69.18, 103.23, 24.31, and 13.57 mg/g, respectively. The competitive adsorption experiments elucidated affinity as Cu(II)>Pb(II)≫Cd(II)>Zn(II). Adsorption time generally required <2.5 h to reach equilibrium; the pseudo-second-order kinetic model well described the kinetics. Chelating ability of free radicals in pigment was considered as a possible mechanism for adsorption. Initial adsorption capacities remained almost intact even after 5 consecutive adsorption-desorption cycles. Complete removal of Cu(II), Pb(II), and Cd(II) from metal-contaminated effluent was confirmed. Consequently, melanin pigment derived from A. resinae can be used as a biosorbent suitable for the treatment of metal-contaminated aqueous solutions.

Selection and characterization of toxic Aspergillus spore-specific DNA aptamer using spore-SELEX.

As airborne spores of toxic Aspergillus species cause mild symptoms to invasive fungal infections, their indoor concentration should be controlled through real-time management. Aptamer-based biosensors could provide economical and simple solutions for point-of-care. In this study, we isolated aptamers binding to the spores of three representative toxic Aspergillus species (A. fumigatus, A. flavus, and A. niger) for the first time, using cell-SELEX (systematic evolution of ligands through exponential enrichment). Among the aptamer candidates, Asp-3 showed a broad and high binding affinity for the Aspergillus spores. Considering the low binding affinity with proteinase-treated spores, we speculated that the Asp-3 binding sites could be possibly associated with cell surface proteins. The high Asp-3 specificity was confirmed by comparing the binding affinity between the Aspergillus target species and other common indoor fungal species. Moreover, we also established quantitative linear relationships between Asp-3 and the spore concentration of each Aspergillus species. Therefore, the selected Asp-3 aptamer, conjugated with detection sensors, could be an effective biorecognition element for the spores of three toxic Aspergillus species.

Fungal melanin as a biocompatible broad-spectrum sunscreen with high antioxidant activity.

Melanin is considered a bio-inspired dermo-cosmetic component due to its high UV absorption and antioxidant activity. Among various melanin sources, fungal melanin is a promising candidate for sunscreen because of its sustainability and scalability; however, quantitative assessment of its function has not yet been sufficiently explored. In this study, melanin samples derived from Amorphotheca resinae were prepared, followed by the evaluation of their sunscreen performance, antioxidant activity, and cytotoxicity. Melanin-blended cream was prepared by blending a melanin suspension and a pure cream. The cream showed an in vitro sun protection factor value of 2.5 when the pigment content was 5%. The cream showed a critical wavelength of approximately 388 nm and a UVA/UVB ratio of more than 0.81, satisfying the broad-spectrum sunscreen requirement. Oxygen radical absorbance capacity assays indicated that fungal melanin had antioxidant activity similar to ascorbic acid but higher than reduced glutathione. Fungal melanin had no statistically significant cytotoxicity to human keratinocyte cell lines until 72 h of exposure, even at a concentration of 4 mg mL-1. Consequently, melanin pigment can be used as a biocompatible broad-spectrum sunscreen with high antioxidant activity and as a practical alternative in dermo-cosmetic formulations.

Marinobacter halodurans sp. nov., a halophilic bacterium isolated from sediment of a salt flat.

A Gram-staining-negative, aerobic, cream-coloured, marine bacterium, with rod-shaped cells, designated strain YJ-S3-2T, was isolated from salt flat sediment of Yongyu-do, Republic of Korea. YJ-S3-2T grew at pH 5.0-9.0 (optimum pH 7.0), 4-45 °C (optimum 30 °C) and with 1-18 % (w/v) NaCl (optimum 6 %). The results of 16S rRNA gene sequence analysis indicated that YJ-S3-2T was closely related to Marinobacter segnicrescens SS011B1-4T (97.0 %) followed by, 'Marinobacter nanhaiticus' D15-8W (96.7 %), Marinobacter bryozoorum 50-11T (96.7 %), Marinobacter koreensis DSMZ 179240T T (96.5 %) and Marinobacter bohaiensis T17T (96.5 %). The average nucleotide identity (ANI) and the genome to genome distance calculator (GGDC) estimate values between YJ-S3-2T and related type strains were 73.7-79.8 and 19.9-22.5 %, and also 73.5 and 20.7 % with Marinobacter hydrocarbonoclasticus. YJ-S3-2T was characterized as having Q-9 as the predominant respiratory quinone and the principal fatty acids (>10 %) were C16 : 0 (22.3 %), summed feature 9 (C17 : 1iso ω9c/C16 : 0 10-methyl, 13.8 %) and 3 (C16 : 1ω7c/C16 : 1ω6c, 11.9 %). The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, two unidentified aminolipids and two unidentified phospholipids. The DNA G+C content of YJ-S3-2T is 60.9 mol%. On the basis of the polyphasic taxonomic evidence presented in this study, YJ-S3-2T should be classified as representing a novel species within the genus Marinobacter, for which name Marinobacter halodurans sp. nov. is proposed, with the type strain YJ-S3-2T (=KACC 19883T=KCTC 62937T=JCM 33109T).

Production and characterization of melanin pigments derived from Amorphotheca resinae.

As melanin has emerged as functional pigment with cosmetic, health and food applications, the demand for the pigments is expected to increase. However, the conventional sources (e.g. mushroom, hair, and wool) of melanin production entail pigments inside the substrates which requires the costly extraction procedures, leading to inappropriate scalable production. In this study, we screened 102 of fungal isolates for their ability to produce melanin in the supernatant and selected the only Amorphotheca resinae as a promising candidate. In the peptone yeast extract glucose broth, A. resinae produced the melanin rapidly during the autolysis phase of growth, reaching up 4.5 g/L within 14 days. Structural characterization of the purified melanin from A. resinae was carried out by using elemental analysis, electron paramagnetic resonance, 13C solid-state nuclear magnetic resonance spectroscopy, and pyrolysis-gas chromatography-mass spectrometry in comparison with the standard melanins. The results indicate that the structural properties of A. resinae melanin is similar to the eumelanin which has a wide range of industrial uses. For example, the purified melanin from A. resinae has the potent antioxidant activities as a result of free radical scavenging assays. Consequently, A. resinae KUC3009 can be a promising candidate for scalable production of industrially applicable melanin.

A proposed stepwise screening framework for the selection of polycyclic aromatic hydrocarbon (PAH)-degrading white rot fungi.

This study suggests a simple three-step screening protocol for the selection of white rot fungi (WRF) capable of degrading polycyclic aromatic hydrocarbons (PAHs), which combines easily applicable bioassay techniques, and verifies that protocol by evaluating the PAH degradation activity, ligninolytic enzyme secretion, and relevant gene expressions of the selected PAH-degraders. Using 120 fungal strains, a sequence of bioassay techniques was applied: Bavendamm's reaction (Step 1), remazol brilliant blue R (RBBR) decolorization (Step 2); assays for tolerance to four mixed PAHs-phenanthrene, anthracene, fluoranthene, and pyrene (Step 3). This stepwise protocol selected 14 PAH-degrading WRF, including Microporus vernicipes, Peniophora incarnata, Perenniporia subacida, Phanerochaete sordida, Phlebia acerina, and Phlebia radiata. Of these, P. incarnata exhibited the highest PAH degradative activity, ranging from 40 to > 90%, which was related to the time-variable secretions of three extracellular ligninolytic enzymes: laccase, manganese-dependent peroxidase (MnP) and lignin peroxidase (LiP). Laccase and MnP production by P. incarnata tended to be greater in the early stages of PAH degradation, whereas its LiP production became intensified with decreasing laccase and MnP production. Pilc1 and pimp1 genes encoding laccase and MnP were expressed, indicating the occurrence of extracellular enzyme-driven biodegradation of PAH by the fungal strains.

Recovery of the benthic bacterial community in coastal abandoned saltern requires over 35 years: A comparative case study in the Yellow Sea.

Salt is an essential nutrient for humans, and salterns exist worldwide. Although the construction of salterns has stopped and typical salterns are now mostly abandoned, there has been no research on the ecological recovery of the abandoned salterns. Here, we analyzed the bacterial diversity and community structure in three pairs of abandoned salterns that have undergone 1-35 years of natural restoration and tidal flats to determine the recovery time and process. Partial 16S rRNA sequences were amplified and sequenced to investigate the biodiversity and structure of the bacterial community in sediments collected from abandoned salterns and adjacent natural tidal flats (viz., controls) in the Yellow Sea. The most abundant microorganisms across locations were found to be members of Proteobacteria, ranging from 45 to 72%, which was also a crucial taxon in the bacterial recovery process. The benthic bacterial community of the salterns showed time-dependent recovery, as demonstrated by the similarity between the salterns and controls. Indeed, dissimilarities between bacterial communities were significant for the saltern that had been abandoned for one year, according to ANOSIM (R = 1.0, p < 0.01). The genera that were determined to contribute to the dissimilarity exhibited a significant correlation with the sedimentary phosphorus concentration. The dataset generally supported that the indigenous benthic bacterial community in an altered marine environment might require a considerable time to return to a natural status. Meanwhile, a delay between the recovery of the physicochemical environment and biological component was evidenced, which seemed to influence the recovery time in a site-specific manner. Overall, the present study provided new insight and understanding of the recovery of the benthic bacterial community in abandoned salterns in terms of recovery time and the associated process.

Fungal Diversity in Intertidal Mudflats and Abandoned Solar Salterns as a Source for Biological Resources.

Intertidal zones are unique environments that are known to be ecological hot spots. In this study, sediments were collected from mudflats and decommissioned salterns on three islands in the Yellow Sea of South Korea. The diversity analysis targeted both isolates and unculturable fungi via Illumina sequencing, and the natural recovery of the abandoned salterns was assessed. The phylogeny and bioactivities of the fungal isolates were investigated. The community analysis showed that the abandoned saltern in Yongyudo has not recovered to a mudflat, while the other salterns have almost recovered. The results suggested that a period of more than 35 years may be required to return abandoned salterns to mudflats via natural restoration. Gigasporales sp. and Umbelopsis sp. were selected as the indicators of mudflats. Among the 53 isolates, 18 appeared to be candidate novel species, and 28 exhibited bioactivity. Phoma sp., Cladosporium sphaerospermum, Penicillium sp. and Pseudeurotium bakeri, and Aspergillus urmiensis showed antioxidant, tyrosinase inhibition, antifungal, and quorum-sensing inhibition activities, respectively, which has not been reported previously. This study provides reliable fungal diversity information for mudflats and abandoned salterns and shows that they are highly valuable for bioprospecting not only for novel microorganisms but also for novel bioactive compounds.

Improvement of Euglena gracilis Paramylon Production through a Cocultivation Strategy with the Indole-3-Acetic Acid-Producing Bacterium Vibrio natriegens.

We investigated the putative effects on the growth and paramylon production of Euglena gracilis of cocultivation with Vibrio natriegensE. gracilis heterotrophically cocultivated with V. natriegens displayed significant increases in biomass productivity and paramylon content. In addition, the effects of the bacterial inoculum density and the timing of inoculation on the growth of E. gracilis were examined, to determine the optimal conditions for cocultivation. With the optimal deployment of V. natriegens, biomass productivity and paramylon content were increased by more than 20% and 35%, respectively, compared to those in axenic E. gracilis cultures. Interestingly, indole-3-acetic acid biosynthesized by V. natriegens was responsible for these enhancements of E. gracilis The morphology of cocultured E. gracilis cells was assessed. Paramylon granules extracted from the cocultivation were significantly larger than those from axenic culture. Our study showed that screening for appropriate bacteria and subsequent cocultivation with E. gracilis represented an effective way to enhance biomass and metabolite production.IMPORTANCEEuglena gracilis has attracted special interest due to its ability to excessively accumulate paramylon. Paramylon is a linear ß-1,3-glucan polysaccharide that is the principal polymer for energy storage in E. gracilis The polysaccharide features high bioactive functionality in the immune system. This study explored a new method to enhance the production of paramylon by E. gracilis, through cocultivation with the indole-3-acetic acid-producing bacterium Vibrio natriegens The enhanced production was achieved indirectly with the phytohormone-producing bacteria, instead of direct application of the hormone. The knowledge obtained in this study furthers the understanding of the effects of V. natriegens on the growth and physiology of E. gracilis.

Serinicoccus sediminis sp. nov., isolated from tidal flat sediment.

A novel Gram-strain-positive, non-spore-forming bacterial strain, designated GP-T3-3T, was isolated from sediment sampled at a tidal flat in Gopado, Republic of Korea. Cells were aerobic, catalase-negative, oxidase-positive, non-motile cocci that occurred singly, in pairs or in clusters. Strain GP-T3-3T grew at 4-45 °C (optimum, 28-37 °C), at pH 4.0-12.0 (pH 8.0-9.0) and in the presence of 0-15 % (w/v) NaCl (3-5 %). Colonies of strain GP-T3-3T were deep-yellow, circular, smooth and pulvinate. The results of the phylogenetic analyses based on 16S rRNA gene sequences indicated that strain GP-T3-3T was closely related to Serinicoccus profundi MCCC 1A05965T (99.1 %), Serinicoccus chungangensis CAU 9536T (99.0 %) and Serinicoccus marinus JC1078T (98.0 %). The diagnostic diamino acid in the cell-wall peptidoglycan was meso-diaminopimelic acid. The predominant respiratory quinone was MK-8(H4) and the major fatty acids were anteiso-C17 : 0, iso-C16 : 0, iso-C15 : 0 and anteiso-C15 : 0. The polar lipid profile consisted of diphosphadidylglycerol, phosphadidylglycerol, phosphatidylcholine, phosphatidylinositol and two unidentified phospholipids. The DNA G+C content was 72.9 mol%. DNA-DNA relatedness values between strain GP-T3-3T and type strains of the genus Serinicoccus ranged from 28.9 to 50.5 %. On the basis of the phenotypic differences and DNA-DNA relatedness data, the isolate represents a new species of the genus Serinicoccus, for which the name Serinicoccussediminis sp. nov. is proposed. The type strain is GP-T3-3T (=KCTC 49173T=JCM 32825T=KCCM 43309T=KACC 19850T).

Importance of functional diversity in assessing the recovery of the microbial community after the Hebei Spirit oil spill in Korea.

Over 10 years after the Hebei Spirit oil spill (HSOS), the concentrations of pollutants, such as TPH and PAHs, in spilled crude oil have recovered to background levels, but in some areas, the environment has not fully recovered. In particular, PAHs were more resistant to degradation, and their persistence could have deleterious impacts on the sediment ecosystem. This study aimed to evaluate the microbial recovery of coastal sediments from the HSOS by analyzing the structure and diversity of the microbial community and its functional contribution to PAHs degradation. High-throughput sequencing on the MiSeq platform was conducted using tidal flat sediments collected in 2014 and 2016 from the area contaminated by the HSOS. The microbial recovery was evaluated by various diversity factors, including microbial composition and structure and functional diversity based on PICRUSt analysis. The abundance of microbial taxa associated with TPH degradation was higher in 2014 than that in 2016, but the taxa associated with PAHs degradation were similar between years. These results are consistent with the dynamics of microbes associated with the fate of pollutants, and they also showed similar tendency in functional profiles. That is, even if the pollutants are completely degraded, the microbial community has not yet completely recovered from the HSOS. The evaluation of microbial ecosystems in contaminated environments should consider both the fate of pollutants and the dynamics of microbial species that make functional contributions to the degradation of pollutants.

Gemmobacter lutimaris sp. nov., a marine bacterium isolated from a tidal flat.

A novel cream-pigmented marine bacterium, designated strain YJ-T1-11T, was isolated from a tidal flat at Yeongjong-do, Republic of Korea. Cells were rod-shaped, non-motile, aerobic, Gram-reaction-negative, oxidase-positive and catalase-positive. Phylogenetic analysis of 16S rRNA gene sequences indicated that strain YJ-T1-11T clustered with Gemmobacter fontiphilus JS43T (98.3 %) within the genus Gemmobacter and its closest neighbours were G.emmobacter aquatilis DSM 3857T (98.5 %), Gemmobacter aquaticus A1-9T (98.4 %), Gemmobacterlanyuensis Orc-4T (98.4 %), Gemmobacterfontiphilus JS43T (98.3 %), Gemmobactercaeni DCA-1T (98.2 %), Gemmobacternanjingensis Y12T (97.5 %) and Gemmobactertilapiae Ruye-53T (97.2 %). Average nucleotide identity values between the genome sequences of strain YJ-T1-11T and the related type strains ranged from 77.08 to 90.48 %. The predominant fatty acid of strain YJ-T1-11T was summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c). The major isoprenoid quinone was Q-10 and the DNA G+C content was 65.6 mol%. The polar lipid profile consisted of phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, diphosphatidylglycerol and three unidentified lipids. The DNA-DNA relatedness values between strain YJ-T1-11T and the type strains of the 12 phylogenetically related species of the genus Gemmobacter were 23.6-53.7 %. On the basis of the genotypic, chemotaxonomic and phenotypic data, strain YJ-T1-11T is considered to represent a novel species of the genus Gemmobacter, for which the name Gemmobacter lutimaris sp. nov. is proposed. The type strain is YJ-T1-11T (=KCTC 62715T=JCM 32828T).

Desorption and solubilization of anthracene by a rhamnolipid biosurfactant from Rhodococcus fascians.

The rhamnolipid biosurfactant-producing bacterium, strain SDRB-G7, was isolated from the sediment of Sindu-ri beach and identified as Rhodococcus fascians based on a phylogenetic analysis. Optimal activity, with the highest yield (2.441 g/L) and surface tension-reducing activity (24.38 mN/m), was observed when the cells were grown on olive oil as their sole source of carbon at pH 8.0. The rhamnolipid biosurfactant showed environmental stability at a variety of NaCl concentrations (2-20%) and pH values (2-12) even under acidic conditions. Of the initial anthracene, 66% was solubilized by 100% crude biosurfactant. Furthermore, 100% crude biosurfactant desorbed 81% of the anthracene in sediment into the aqueous phase. These results suggest that the rhamnolipid biosurfactant produced from R. fascians SDRB-G7 is a promising candidate for polycyclic aromatic hydrocarbon (PAH) removal from the sediment and can be an effective agent for processes that bioremediate PAHs such as surfactant-enhanced remediation. PRACTITIONER POINTS: Biosurfactants can accelerate desorption of PAHs and improve their solubility. BS-producing R. fascians SDRB-G7 was selected by screening of biochemical tests. Solubility of anthracene was enhanced by rhamnolipid produced by strain SDRB-G7. Microbial surfactant is a promising alternative for bioremediation of PAH-polluted sites.

Decolorizing an anthraquinone dye by Phlebia brevispora: Intra-species characterization.

Remazol brilliant blue R (RBBR) is an anthraquinone dye derived from anthracene that is decolorized by a white rot fungus, Phlebia brevispora. Interestingly, P. brevispora produces two phenomena of yellowish and pinkish colors during the degradation of RBBR. Here, we characterized the decolorization of RBBR by P. brevispora. The fungus was significantly different between the two colors via UV spectrophotometry, and the morphology of the hyphae observed in the respective color culture was also entirely different. Moreover, both of the two ligninolytic enzymes, laccase and manganese-dependent peroxidase (MnP), were remarkably stimulated in the yellowish culture at the beginning of the decolorization. It is possible that the RBBR decolorizing mechanism might be primarily related to the amount of laccase and MnP produced in the yellowish culture. Thus, the decolorized color may be rapidly estimated at initial period of incubation. In addition, GeneFishing technology revealed that two genes were differentially expressed in yellowish culture.

Heterologous expression of a new manganese-dependent peroxidase gene from Peniophora incarnata KUC8836 and its ability to remove anthracene in Saccharomyces cerevisiae.

The white rot fungus Peniophora incarnata KUC8836 has received an attention as the greatest degrader of polycyclic aromatic hydrocarbons (PAHs), which are hazardous xenobiotics and recalcitrant pollutants. To characterize the mechanisms through which MnP degrades PAHs, heterologous expression of manganese-dependent peroxidase (MnP) gene pimp1 was performed in Saccharomyces cerevisiae BY4741 via the pGEM-T Easy vector, resulting in the recombinant plasmid pESC-URA/pimp1 containing the MnP signal peptide. MnP was significantly secreted into the culture medium with galactose as an active protein with higher efficiency (3.58 U mL-1) by transformants than by the wild-type S. cerevisiae. The recombinant MnP protein was shown to have a molecular weight of 44 kDa by western blotting analysis. With regard to enhancing the bioremediation of PAHs in the environment, anthracene was effectively degraded by the MnP encoded by pimp1, with a degradation rate of 6.5% when Tween 80 was added. In addition, the MnP activity of the transformant exhibited the highest efficiency (2.49 U mL-1) during the degradation. These results show that pimp1 might be useful for biodegradation and gene expression technologies at a transcriptional level, and genetic approaches can be improved by incorporating the highly ligninolytic gene pimp1 and the fungus P. incarnata KUC8836.

Bioleaching of spent Zn-Mn or Ni-Cd batteries by Aspergillus species.

This research explores the recovery of metals from spent Zn-Mn or Ni-Cd batteries by a bioleaching using six Aspergillus species. Two different nutrients, malt extract and sucrose, were used to produce different types of organic acids. Oxalic acid and citric acid were shown to be the dominant organic acid in malt extract and sucrose media, respectively. In the bioleaching, the metal removal was higher in sucrose media than malt extract. All species, except A. niger KUC5254, showed more than 90% removal of metals from Zn-Mn battery. For Ni-Cd battery, more than 95% of metals was extracted by A. niger KUC5254 and A. tubingensis KUC5037. As a result, A. tubingensis KUC5037 which is a non-ochratoxigenic fungus was considered to have the greatest potential for improving the safety and efficiency of the bioleaching.