Penicillium glabrum cork-colonising isolates - preliminary analysis of their genomic similarity

The cork stopper manufacturing process includes an operation, known as stabilisation, by which humid cork slabs are extensively colonised by fungi. The effects of fungal growth on cork are not completely understood although they are considered to be involved in the so-called "cork taint" of wine. It is essential to (a) identify environmental constraints which define the appearance of the colonising fungal species and (b) trace their origin to the forest and/or the manufacturing space. The present article correlates two sets of data, from consecutive years and the same season, of systematic sampling of two manufacturing units, located in the North and South of Portugal. Chrysonilia sitophila dominance was confirmed, followed by a high diversity of Penicillium species. Penicillium glabrum, which was found in all samples, was the most frequently isolated species. P. glabrum intra-species variability was investigated using DNA fingerprinting techniques revealing highly discriminative polymorphic markers in the genome. Cluster analysis of P. glabrum data was discussed in relation to the geographical location of strains, and results suggest that P. glabrum arise from predominantly the manufacturing space, although cork specific fungi can contribute.     

Effect of fungal colonization on mechanical performance of cork

The industrialization of traditional processes relies on the scientific ability to understand the empirical evidence associated with traditional knowledge. Cork manufacturing includes one operation known as stabilization, where humid cork slabs are extensively colonized by fungi. The implications of fungal growth on the chemical quality of cork through the analysis of putative fungal metabolites have already been investigated. However, the effect of fungal growth on the mechanical properties of cork remains unexplored. This study investigated the effect of cork colonization on the integrity of the cork cell walls and their mechanical performance. Fungal colonization of cork by Chrysonilia sitophila, Mucor plumbeus Penicillium glabrum, P. olsonii, and Trichoderma longibrachiatum was investigated by microscopy. Growth occurred primarily on the surface of the cork pieces, but mycelium extended deeper into the cork layers, mostly via lenticular channels and by hyphal penetration of the cork cell wall.In this first report on cork decay in which specific correlation between fungal colonization and mechanical proprieties of the cork has been investigated, all colonizing fungi except C. sitophila, reduced cork strength, markedly altering its viscoelastic behaviour and reducing its Young's modulus.     

Cork stoppers industry: defining appropriate mould colonization

AIMS: The main aims of this work were the study of cork slabs moulds colonization and the evaluation of the moulds diversity during cork processing steps, in different cork stoppers factories. Simultaneously, it was envisaged to perform an evaluation of the air quality. METHODS AND RESULTS: Moulds were isolated and identified from cork slabs and cork samples in four cork stoppers factories. The identification was based on morphological characters and microscopic observation of the reproductive structures. Airborne spore dispersion was assessed using a two stage Andersen sampler. It was observed that Chrysonilia sitophila was always present on cork slabs during the maturing period, but mould diversity appeared to be associated to the different factory configurations and processing steps. CONCLUSIONS: Spatial separation of the different steps of the process, including physical separation of the maturation step, is essential to guarantee high air quality and appropriate cork slabs colonization, i.e. C. sitophila dominance. The sorting and cutting of the edges of cork slabs after boiling and before the maturing step is also recommended. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is very important for the cork stopper industry as it gives clear indications on how to keep high quality manufacturing standards and how to avoid occupational health problems.     

Fungal Biodegradation and Detoxification of Cork Boiling Wastewaters

The ability of several fungal strains to degrade and to detoxify cork boiling wastewaters was investigated. The fungal strains used in this work were Sporothrix sp., Trichoderma koningii, Chrysonilia sitophila and Penicillium glabrum isolated from cork bark as well as Fusarium flocciferum and Phanerochaete chrysosporium. The results obtained in the degradation experiments carried out with each fungus showed that all fungi display similar abilities, with a chemical oxygen demand reduction of 54.2 % (± 4.7 %) attained within five days of incubation. F. flocciferum presented the highest value for the reduction of chemical oxygen demand of 62 %. In addition, a rise in pH values of around 3 units was detected with all the strains, except for Penicillium glabrum. Toxicity tests performed on Vibrio fischeri revealed that fungal treatment of the wastewaters causes the complete loss of toxicity in the cases of Sporothrix sp., T. koningii, P. chrysosporium and F. flocciferum. The other two tested strains were also able to detoxify the raw wastewaters, causing a ten‐fold decrease in toxicity. The results obtained in sequential biodegradation experiments with different pairs of fungi showed that although the increment in the COD reduction did not exceed 10 %, an important reduction in toxicity and a pH rise were attained.     

Mites and fungi in heavily infested stores in the Czech Republic

Toxigenic and allergen-producing fungi represent a serious hazard to human food and animal feed safety. Ninety-four fungal species were isolated from mite-infested samples of seeds taken from Czech seed stores. Fungi were isolated from the surface of four kinds of seeds (wheat, poppy, lettuce, and mustard) and from the gut and external surface of five species of mites (i.e., Acarus siro L., 1758, Caloglyphus rhizoglyphoides (Zachvatkin, 1973), Lepidoglyphus destructor (Schrank, 1781), Tyrophagus putrescentnae (Schrank, 1781) and Cheyletus malaccensis Oudemans 1903) separately. Multivariate analysis of fungi complex composition showed that the frequency of fungal was species significantly influenced by the kind of seed. Fungal frequencies differed between mites gut and exoskeleton surface and between the surfaces of mites and seeds. Three groups of fungal species were recognized: 1) mite surface-associated fungi: Penicillium brevicompactum, Alternaria alternata, and Aspergillus versicolor; 2) mite surface- and seed-associated fungi: Aspergillus niger, Penicillium crustosum, Penicillium aurantiogriseum, Penicillium chrysogenum, and Aspergillus flavus; and 3) seed-associated fungi: Cladosporium herbarum, Mucor dimorphosporus f. dimorphosporus, Botrytis cinerea, Penicillium griseofulvum, and Eurotium repens. Mite-carried species of microfungi are known to produce serious mycotoxins (e.g., aflatoxin B1, cyclopiazonic acid, sterigmatocystin, ochratoxin A, and nephrotoxic glycopeptides) as well as allergen producers (e.g., A. alternata and P. brevicompactum). Storage mites may play an important role in the spread of some medically hazardous micromycetes. In addition, these mite-fungi associations may heighten the risk of occurrence of mycotoxins in food and feed stuffs and cause mixed contamination by fungal and mite allergens.     

Monitoring of microbial degraders in manned space stations

Samples of microorganisms from the surface of constructions of Mir Space Station (Mir SS) were taken and examined after 13 years of operation. The following microorganisms were isolated and identified: 12 fungal species belonging to the genera Penicillium, Aspergillus, Cladosporium, and Aureobasidium; 3 yeast species belonging to the genera Debaryomyces, Candida, and Rhodotorula; and 4 bacterial species belonging to the genera Bacillus, Myxococcus, and Rhodococcus. The predominant species in all samples was Penicillium chrisogenum. It was shown that the fungi isolated could damage polymers and induce corrosion of aluminum-magnesium alloys. We commenced a study of microbial degraders on constructions of the Russian section of the International Space Station (RS ISS). Twenty-six species of fungi, bacteria, yeasts, and actinomycetes, known as active biodegraders, were identified in three sample sets taken at intervals. We founded a collection of microorganisms surviving throughout space flights. This collection can be used to test spacecraft production materials, in order to determine their resistance to biodegradation.     

Studies on microbial antagonism in the establishment of clover pasture

Summary Fungi inhabiting soil recently cleared of the native vegetation have been isolated and compared with those isolated from under established clover pastures, Three methods of isolation of the fungi were used in each situation, and profoundly influenced the population obtained.In newly cleared soils the composite fungal population pattern deduced all three isolation methods comprised species of Mortierella, Phoma, Trichoderma, Penicillium, Fusarium, Sclerotium and non-sporing mycelia. In soil supporting established clover pastures the main rhizosphere fungi were species of Fusarium, Aspergillus, Phoma, Curvularia, Macrophomina, Sclerotium and one Ascomycete.Fusarium oxysporum was the most frequently isolated fungus.Conventional plating techniques suggested that the dominant fungi in the rhizosphere of clover wereFusarium oxysporum andAspergillus versicolor, whereas isolation of fungi from hyphae adhering to the clover roots indicated that species of Macrophomina, Curvularia and an Ascomycete were the most abundantly occurring organisms. In the case of the root residues of the native vegetation in newly cleared soils plating techniques resulted in species of the freely sporing Mortierella, Trichoderma, Aspergillus, Fusarium and Penicillium occurring most frequently, whereas the isolation of fungi from hyphal strands on the residues gave a population pattern dominated by species of Mortierella, Phoma, Sclerotium, and non-sporing mycelia.The study indicated a marked succession of fungal species during the decomposition of the root debris in newly cleared soils, and also that some early members of this changing population might exert an adverse effect on the establishment of clover.     

Mycobiota in Portuguese 'normal' and 'green' cork throughout the manufacturing process of stoppers

The compounds responsible for the so-called 'cork taint' include, among others, some microbial metabolites which can be produced by the microbial population colonizing the unprocessed cork and stoppers. This study was intended to obtain information on the mycobiota associated with Portuguese cork throughout the manufacturing process of stoppers. Samples of barks and stoppers of both 'normal' and 'green' cork were examined. Moulds were isolated from 'normal' and 'green' cork throughout the entire cork stopper manufacturing process. Yeasts were rarely detected in the corks. Fungal contamination was not detected in finished stoppers from the company under study.     

烟叶陈化过程可培养微生物的生态功能

【背景】烟叶陈化涉及多方面因素的相互作用。【目的】研究烟叶表面可培养微生物群落结构、功能和化学成分之间的联系。【方法】以储存于贵阳库、坛厂库、茅台库的烟叶为研究对象,分别对不同陈化时间的烟叶样品进行微生物分离,采用rDNA条形码技术对微生物优势菌株进行物种鉴定,利用FAPROTAX和FUNGuild数据库分别对细菌和真菌进行功能注释,并结合主要化学成分进行相关分析。【结果】243个烟叶样品中共分离到189株优势细菌菌株和229株优势真菌菌株,其中细菌以芽孢杆菌属(Bacillus)为优势种群,真菌以曲霉属(Aspergillus)和青霉属(Penicillium)为优势种群。随着陈化时间的延长,优势种群和优势功能类群比例逐渐降低,主要化学成分与微生物群落变化呈显著相关关系。【结论】微生物功能群通过结构变化推动烟叶陈化进程,同时陈化过程中主要化学成分的变化影响了微生物群落的组成与功能。     

Effectiveness of imazalil to control the effect of fungal deterioration on mummies at the Mexico City Museum "El Carmen"

We present a study on the control and elimination of the fungi affecting the mummies specifically at the museum "El Carmen", in San Angel, Mexico City. Twelve analysed mummies presented an important deterioration attributed to colonizing fungi. The degree of fungal contamination and the efficacy of imazalil were evaluated. Two samplings were performed in order to isolate and identify the fungal genera, one for control and the other after the treatment. Isolation was done by the carpet-square technique and identification was performed by morphological features. Each sampling gave a total of 100 samples as follows: 17 from the air, 23 from the walls and 60 from the mummies. Samples were cultured on Sabouraud dextrose agar. From the first sampling a total of 649 colonies corresponding to 24 genera were obtained being the most frequent Penicillium, Cladophialophora and Aspergillus. From the second sampling, after the imazalil treatment, which was applied by means of lit candles containing the antifungal drug, 57 colonies were recovered, representing a 91.2% fungal reduction; 18 genera were eliminated. In spite of resistance showed by many Penicillium strains, the imazalil is an alternative drug for the control of fungal colonization on these studied materials.     

The relationship between a leaf-rolling moth (Dactylioglypha tonica) and fungi covering the cocoon.

To discover the relationship between a leaf-rolling moth and the fungi densely covering its cocoons, the rolled nest leaves were collected in two districts in Japan and antibacterial properties of the fungi were examined. Cocoons and fungi isolated from the nest were classified into 5 categories by the growth stages of the insects, and 7 categories based on taxonomic properties and pigment productivity, respectively. The dominant genus was Penicillium in each location. However, the composition of the fungal categories was different and seemed to depend on their circumstances. From all cocoons with larvae, the strains that belonged to the same fungal category and produced the same antibiotic (deoxyherqueinone) were isolated. From these results, the species-specific relationship between the insect and fungi or fungal products was considered to be not extremely tight, and it was suggested the period of the larval spinning of the cocoon is a key stage of this unique relationship.     

Biotechnological management of coffee pulp — isolation,screening, characterization,selection of caffeine-degrading fungi and natural microflora present in coffee pulp and husk

A total of 272 strains of filamentous fungi were isolated from soil, leaves of coffee plants and coffee cherries collected in coffee-growing areas of Mexico on three semi-synthetic culture media containing coffee extract, coffee extract with sucrose and coffee pulp extract. The isolated strains were purified by conventional techniques and identified by microscopic examination. Strains were selected on the basis of their caffeine-degrading ability in well-defined liquid medium containing caffeine. Most of the isolated microorganisms belong to Aspergillus, Penicillium, Trichoderma, Fusarium, and Humicola genera. Five strains belonging to Aspergillus species and two strains belonging to Penicillium species had the ability to degrade almost 100% of the caffeine in liquid medium. A comparative study on the evaluation of natural microflora present in coffee pulp and coffee husk revealed the presence of a wide variety of microorganisms. The percentage distribution of fungi, bacteria and yeast was almost similar in all the samples, except in coffee husk where the fungal population was slightly higher than in the other two samples. The yeast population was predominant when the coffee pulp was lyophilized immediately after pulping. However, there was a wide diversity in the microbial population with respect to selective media containing functional nutritional groups like cellulose, starch and pectin.     

Fungal flora of the digestive tract of Panstrongylus megistus (Reduviidae) used for experimental xenodiagnosis of Trypanosoma (Schizotripanum) cruzi Chagas, 1909

A survey of the fungi isolated from the digestive tract of Panstrongylus megistus (insects vectors from Chagas' disease) used on xenodiagnosis was carried out. Two hundred and fourteen fungal strains were isolated from 180 nymphs. Aspergillus and Penicillium were the most predominant genera and some of their species were new records concerning insects. A great reduction in the fungal population was observed in the material that was positive for Trypanosoma cruzi.     

Fungal flora on board the Mir-Space Station, identification by morphological features and ribosomal DNA sequences

This report is on the morphological and molecular biological identification, using 18S- and ITS1-rDNA sequences, of the "space fungi" isolated on board the Russian Mir-Space Station as the major constituents of the fungal flora. The six fungal strains were isolated from air by using an air sampler or from condensation. Strains were identified as Penicillium chrysogenum, Aspergillus versicolor, or Penicillium sp. by both methods. The species of space fungi were common saprophytic fungi in our living environment, potential pathogens, and allergens. This study concluded that the environment on board the space station Mir allows the growth of potentially pathogenic fungi as true in residential areas on the earth. Therefore, to prevent infection or other health disorders caused by these fungi, easy and reliable methods should be established to survey the fungal flora in a space station.     

Fungal survival in ensiled swine faeces

The survival of several genera of fungi was determined in the ensiled solid fraction of swine faeces after 0, 7, 14, 28 and 56 days of ensiling. The experiment had two treatments, un-ensiled and ensiled manure, in a split-plot design. The manure was distributed into 50 containers; samples, taken at the specified times, were cultured in agar potato dextrose medium, incubated, and colony forming units (CFU/g) were counted and log-transformed. The ensiling process decreased the number of CFU after 56 days. Five fungal genera were identified (Absidia spp., Aspergillus spp., Penicillium spp., Rhizopus spp. and non-fructiferous fungi), and their vulnerability to the ensiling conditions varied, although most of them slowed their growth or disappeared after 14 days of ensiling.     

Fungal diversity in activated sludge from membrane bioreactors in Berlin

The objective of this study was to evaluate the occurrence of fungi in aerobic and anoxic activated sludge from membrane bioreactors. Thirty-six samples from each aerobic and anoxic activated sludge were taken from two membrane bioreactors treating domestic wastewater. Over a period of 9?months, four samples from each plant were taken per month. The samples were prepared for count and identification of fungi. Sixty species belonging to 30 genera were collected from activated sludge samples under aerobic and anoxic conditions. In terms of fungal identification, under aerobic conditions Geotrichum candidum was found at 94.4% followed by Penicillium species at 80.6%, yeasts at 75.0%, and Trichoderma species at 50.0%; under anoxic conditions G. candidum at 86.1%, yeasts at 66.6%, and Penicillium species at 61.1% were the most prevalent. The results indicate that activated sludge is a habitat for growth and sporulation of different groups of fungi, both saprophytic and pathogenic.     

湛江红树林滩涂可培养真菌种群多样性分析

【目的】明确湛江地区红树林滩涂海洋真菌的种类及其分布,为海洋真菌的开发利用研究奠定基础。【方法】运用稀释平板法从湛江市高桥及特呈岛红树林滩涂不同的潮位带(低、中、高)和不同树种(白骨壤、桐花树、木榄、红海榄)采集淤泥样品550份,采用真菌形态学和ITS序列分析技术进行多样性研究【。结果】分离获得海洋真菌274株,共鉴定出19属39种真菌,以曲霉属Aspergillus、青霉属Penicillium和木霉属Trichoderma真菌分离频率高,为湛江红树林滩涂优势真菌种类,尤其在中潮位带真菌种类最多。此外,分离获得真菌Talaromyces helicus,为中国新记录种。【结论】湛江红树林滩涂海洋真菌的种类十分丰富,具有潜在的开发和利用前景。     

Polyphasic identification of yeasts isolated from bark of cork oak during the manufacturing process of cork stoppers

A two-step protocol was used for the identification of 52 yeasts isolated from bark of cork oak at initial stages of the manufacturing process of cork stoppers. The first step in the identification was the separation of the isolates into groups by their physiological properties and RFLPs of the ITS-5.8S rRNA gene. The second step was the sequencing of the D1/D2 domains of the 26S rRNA gene of selected isolates representing the different groups. The results revealed a predominance of basidiomycetous yeasts (11 species), while only two species represented the ascomycetous yeasts. Among the basidiomycetous yeasts, members representing the species Rhodosporidium kratochvilovae and Rhodotorula nothofagi, that have been previously isolated from plant material, were the most abundant. Yeasts pertaining to the species Debaryomyces hansenii var. fabryii, Rhodotorula mucilaginosa and Trichosporon mucoides were isolated in small numbers.     

核辐射污染区真菌的分布及多样性研究

为揭示中国辐射污染区真菌多样性,了解辐射污染对辐射区土壤中真菌群落分布的影响。以中国辐射污染区某污染源为圆心,在其半径50 km范围内采集各类样品54份,依据其辐射剂量合并为高、中、低三组9份样品,采用不同处理方法及多种培养基对辐射区内真菌进行了分离筛选。共分离出真菌209株,通过形态学观察和鉴定,确定其分属于交链孢霉(Alternaria)、离蠕孢属(Bipolaris)、茎点霉属(Phoma)、Westerdykella、短梗霉属(Aureobasidium)、曲霉属(Aspergillus)、青霉属(Penicillium)、根霉属(Rhizopus)、Kernia、毛壳属(Chaetomium)、葡萄穗霉属(Stachybotrys)、座孢霉属(Myrothecium)、镰孢属(Fusarium)、小克银汉霉属(Cunninghamella)、红酵母属(Rhodotorula)、隐球酵母属(Cryptococcus),共计16个属,其中曲霉属、隐球酵母属、青霉属和镰孢霉属菌株为主要菌群,分别占分离株的22.5%、19.1%、17.2%和11.0%。同时发现,辐射污染区真菌的群落丰富度及多样性明显受辐射污染程度的影响,各类菌株的分布呈现一定的分布规律。本研究首次分析了中国辐射污染区真菌的分布和多样性,并收集了大量辐射污染区真菌资源,为进一步研究该区域真菌耐辐射特性及探讨真菌耐辐射机理提供参考。     

Fungi inhabiting the healthy human gastrointestinal tract: a diverse and dynamic community

Fungal DNA was selectively amplified, and the ITS region sequenced, from fecal samples taken from 45 healthy human volunteers at one (21 volunteers) or two (24 volunteers) time points. Seventy-two operational taxonomic units, representing two phyla and ten classes of fungi, were recovered. Candida yeasts, notably Candida tropicalis (present in 51 samples), and yeasts in the Dipodascaceae (39 samples), dominated, while 38 OTUs were detected in a single sample each. Fungi included known human symbionts (Candida, Cryptococcus, Malassezia and Trichosporon spp.), common airborne fungi (Cladosporium sp.) and fungi known to be associated with food (Debaryomyces hansenii and high salt fermented foods; Penicillium roqueforti and blue cheese). In contrast with gut-associated bacteria, fungi occurred in much lower abundance and diversity, and fungal composition appeared unstable over time.