Contamination of common spices in Saudi Arabia markets with potential mycotoxin-producing fungi

Fifteen spices obtained from common markets were examined for their mould profile. A total of 520 fungal isolates, representing 57 species, were recovered and identified from dried and ground spice samples on three different media using standard dilution plate method. The most heavily contaminated spice samples examined were observed in ginger in order of magnitude of 5325–6800 cfu/g. The most predominant fungal genera encountered were Aspergillus, Penicillium, and Rhizopus. Relative occurrence values of taxa disclosed ranged between 80% for Aspergillusflavus, Aspergillusniger and Penicilliumarenicola, and 10% for some species. Samples obtained from sumac encountered very rare colony counts indicating its antifungal prosperities. The present magnitude of contamination and spectra of mycobiota approximate those reported for similar spice samples. Several potentially mycotoxigenic fungi were isolated from the majority of samples. The present study attracts the attention to potential risk for mycotoxins contamination may be caused as a result of using these spices, especially in great quantities. The study strongly recommends reduction in application of heavily contaminated spices like ginger in food processing and using some others like clove and sumac due to their antimicrobial properties.     

Fungi associated with food and feed commodities from Ecuador

Freshly harvested soybean, rice and corn from farms and corn-based pelleted feeds were collected from ranches from the coastal and mountain regions in Ecuador during 1998, and assessed for fungal contamination. The most prevalent fungi on pelleted feed were Aspergillus flavus and Fusarium graminearum. The prevalent fungi recovered from soybean were F. verticillioides, F. semitectum, Aspergillus flavus and A. ochraceus. In rice, F. oxysporum was the most prevalent toxigenic fungal species recorded, followed by F. verticillioides and A. flavus. In corn, F. verticillioides was the most prevalent fungus isolated in both the coastal and mountain regions, with high isolation frequencies of A. flavus and A. parasiticus at the coast. Based on the toxigenic species recovered, ochratoxin A may pose a contamination risk for soybean. A higher probability of aflatoxin contamination of corn was found in the coastal samples compared to those of the mountain region, while a risk of fumonisin contamination of corn exists in both regions.This revised version was published online in October 2005 with corrections to the Cover Date.     

Endophytic fungi associated with the Antarctic grass <Emphasis Type="Italic">Deschampsia antarctica</Emphasis> Desv. (<Emphasis Type="Italic">Poaceae</Emphasis>)

Deschampsia antarctica Desv. (Poaceae) represents one of the two vascular plants that have colonized the Antarctic continent, which is usually exposed to extreme environmental conditions. In this work, we have characterized the endophytic fungi associated with the leaves of D. antarctica. Endophytic fungi were recovered from 91 individual plants from different points of Admiralty Bay at King George Island, Antarctica. A total of 26 fungal isolates were obtained from 273 leaf fragments. All isolates were identified by analysis of the sequences of the internal transcribed spacer region (ITS) of the rDNA. Alternaria and Phaeosphaeria were the most frequent genera associated with the plant. Other fungal isolates were identified as Entrophospora sp. and several undescribed Ascomycete species. An interesting result was obtained for the isolates UFMGCB 215 and UFMGCB 262, which were related to fungi associated with bryophytes present in boreal ecosystems. Some isolates showed low identity in the ITS sequences to sequences of fungal species deposited in GenBank, suggesting that these fungi could be new species. This work is the first report on fungal endophytes associated with leaves of the Antarctic grass D. antarctica.     

Natural occurrence of mycotoxins and mycoflora of argentinien popcorn

Argentina is the first popcorn exporting country worldwide. In 1997-1998 harvest season, 40,000 ha were sown with a production of 125,000 tons; 120,000 tons of this production were exported to more than 40 countries. The objectives of this study were to isolate and to identify the fungi present in this cereal and to assess the occurrence of mycotoxins in freshly harvested popcorn in Buenos Aires province, Argentina, in 1999. All popcorn samples showed fungal contamination. A total of 4,211 isolates were recovered from popcorn kernel samples. The prevalent species isolated wasFusarium verticillioides followed byPenicillium funiculosum, F. graminearum andAlternaria alternata. No aflatoxins, zearalenone, deoxynivalenol or ochratoxin A were detected in the 42 popcorn simples. All samples but one were contaminated with fumonisins (FB) in a range in ug/kg of (not detected-529) for FB₁; (not detected-216) for FB₂ and (not detected-103) for FB₃. Fumonisin contamination levels in Argentinean popcorn were lower than observed in flint corn. No significant differences in fungal and fumonisins contamination levels were observed in the different tested hybrids.     

Contribution of leaf surface fungi to the air spora

High concentrations of airborne fungal spores frequently occur from spring through fall in temperate areas of the world. Although it is generally assumed that fungi on leaf surfaces are contributors to the air spora, little data are available comparing the types of fungi found on leaf surfaces with those in the atmosphere. Air sampling was carried out with a Burkard Spore Trap located on the roof of a building on the University of Tulsa campus using standard methods. Leaf samples were aseptically collected from Ulmus americana and Quercus palustris trees on campus, placed in sterile plastic bags, and brought to the lab. For each leaf, 4 cm² areas of both upper and lower leaf surfaces were swabbed and plated on malt extract agar with streptomycin. Cultures were incubated at room temperature for 5–7 days and then examined microscopically. Results were expressed as colony forming units (CFU)/cm². Twenty-one fungal taxa were identified from the air samples. The most abundant taxa were Cladosporium, ascospores, basidiospores, and Alternaria; together these four spore types comprised over 90% of the yearly total. Yeasts were the most abundant fungi isolated from both leaf types. Among the mycelial fungi were Phoma species, followed by Cladosporium and Alternaria. Overall twenty genera of filamentous fungi were identified. Yeasts and Phoma are normally splash dispersed and were not identified in the Burkard air samples. However, 10 taxa isolated from leaf surfaces were registered in air samples. Crude estimates of the leaf surface area of each tree suggest that the total fungal load was approximately 5.04×10⁸ CFU for Ulmus and 2.71×10⁸ CFU for Quercus. Of these levels, 19% were from fungi also detected in air samples. The data suggest that some leaf-surface fungi are major contributors to the air spora.     

Fungal Contamination of Non-Renewable Groundwater in the Arabian Peninsula: Assessing the Harmfulness to Humans

Most of the studies about the groundwater quality have been focused on chemical and bacterial contamination. However, fungal contamination of drinking water has been suggested as an underestimated problem. We studied 20 wells in the Arabian Peninsula, identified their fungal contamination and assessed the potential harmfulness of the fungi to humans. We identified 28 fungal species, many of them commonly known to occur in drinking water. To assess the potential role of fungi in water, we selected 15 species for a bioassay with a model bacterium Bacillus subtilis. All fungal species inhibited the growth of B. subtilis, thus showing antibacterial activity. These fungi were interpreted to secrete toxins and thus, be possibly harmful to humans. Nine of the species retained their antibacterial activity in a boiling treatment. Therefore, they cannot be disinfected by boiling. This study raises new aspects and questions about the harmfulness of the fungal contamination in drinking water to humans.     

Contamination of air systems: 1987–88 assessment and prospects of the Grenoble intervention group

Summary In order to evaluate bacterial and fungal contamination, the authors used a qualitative and quantitative procedure and investigated 47 air conditioning and humidifying units. Air samples were studied using Biotest RCS biocollector (160×6 liters on 6 different selective media), whilst dust samples were analysed after spreading 10 mg onto fungal media. Selective research ofLegionella and fungi were performed using water filtrates and specific media. Even though, the most frequently identified species were quite common environmental fungi, mainlyPenicillium, Alternaria andAspergillus fumigatus (36 out of 47 collections), the health effects of intense exposure to these common moulds are not really known.Staphylococcus aureus was identified 6 times and thermophilic actinomyces species (A. candidus) once. From the quantitative analysis a significant relationship was found between some risk factors and airborne contamination. Indeed bacteria and fungi number depends on the humidifying system (steam or washer), efficiency of secondary filters, relative humidity percentage (< or >60%), installation maintenance, industrial activity and complaints of people at risk. The presence of air recycling and biocide use seems only to have an influence on fungal flora. Having determined a global risk score for each air conditioning unit, the authors underline the fact that bacterial and fungal airborne contamination increases with score. Moreover, for a global, metrological, medical and technical evaluation, a multidisciplinary approach has proved itself to be indispensable.     

Identification and seasonal distribution of airborne fungi in three horse stables in Italy

Fungal agents are responsible for a variety of respiratory diseases both in humans and animals. The nature and seasonal variations of fungi have been investigated in many environments with wide ranging results. The aims of the present report were (i) to evaluate the quality and magnitude of exposure to airborne fungi in three differently structured equine stalls (open air, partially and completely enclosed buildings) during a one-year period, using an air sampling technique and (ii) to compare the distribution and frequency of fungal species, with regards to these different environments. Air samples were collected monthly from December 2001 to November 2002 by means of a surface air sampler (SAS) Super-90, (PBI International, Milan, Italy). Penicillium and Aspergillus spp. were cultured from all the stables in all seasons. Mucoraceae were also recovered in all seasons in stalls 1 and 2, while they were not isolated in spring and fall in stall 3. These fungi were detected in 28.4%, 72.9% and 60.5% of the total number of samples, respectively. Other fungal genera such as Alternaria, Cladosporium, Fusarium, Beauveria and Drechslera were also occasionally recovered.Viable fungal concentrations varied greatly, ranging from below the limit of detection to more than 3000 CFU/m³ for stables 1 and 2, and 1750 CFU/m³ for stable 3. The median fungal concentration was approximately 178 CFU/m³. Total fungal concentration appeared to be highest in summer, winter and spring, and lowest in the fall.     

Recurrent Aspergillus contamination in a biomedical research facility: a case study

Fungal contamination of biomedical processes and facilities can result in major revenue loss and product delay. A biomedical research facility (BRF) culturing human cell lines experienced recurring fungal contamination of clean room incubators over a 3-year period. In 2010, as part of the plan to mitigate contamination, 20 fungal specimens were isolated by air and swab samples at various locations within the BRF. Aspergillus niger and Aspergillus fumigatus were isolated from several clean-room incubators. A. niger and A. fumigatus were identified using sequence comparison of the 18S rRNA gene. To determine whether the contaminant strains isolated in 2010 were the same as or different from strains isolated between 2007 and 2009, a novel forensic approach to random amplified polymorphic DNA (RAPD) PCR was used. The phylogenetic relationship among isolates showed two main genotypic clusters, and indicated the continual presence of the same A. fumigatus strain in the clean room since 2007. Biofilms can serve as chronic sources of contamination; visual inspection of plugs within the incubators revealed fungal biofilms. Moreover, confocal microscopy imaging of flow cell-grown biofilms demonstrated that the strains isolated from the incubators formed dense biofilms relative to other environmental isolates from the BRF. Lastly, the efficacies of various disinfectants employed at the BRF were examined for their ability to prevent spore germination. Overall, the investigation found that the use of rubber plugs around thermometers in the tissue culture incubators provided a microenvironment where A. fumigatus could survive regular surface disinfection. A general lesson from this case study is that the presence of microenvironments harboring contaminants can undermine decontamination procedures and serve as a source of recurrent contamination.     

Bacteria associated with the sponge Spongia officinalis as indicators of contamination

A lot of micro-organisms can been found in the sponge body. In the present study, bacteria and fungi were isolated from the massive commercial sponge Spongia officinalis Linnaeus, 1759 (Porifera, Demospongiae). Samples (sponge extract and sea water) were collected from several areas of the Aegean Sea (ports, beaches, eutrophic gulf and open sea) with different levels and types of contamination. Bacteria identified in sponge extract belong to the genera Escherichia, Morganella, Proteus, Pasteurella, Aeromonas, Pseudomonas and Acinetobacter. Two fungal genera, Trichosporum and Fisarium, were identified in sponge extract. Bacterial load was greater in sponge extract than in proximal sea water, reflecting the sponge ability to concentrate bacteria in its body. The assessment of bacteria associated with the sponge S. officinalis as indicators of contamination is proposed.     

Occurrence and diversity of entomopathogenic fungi in cultivated and uncultivated soils in Pakistan

The distribution of entomopathogenic fungi in various geographical areas of Punjab, Pakistan, is poorly understood. The present study was planned to explore the occurrence and diversity of entomopathogenic fungi from soils collected from cultivated and non‐cultivated habitats. The detailed survey of different habitats (crop fields, fruits, vegetables, forests) was conducted to collect soil samples and the associated fungi were isolated using Galleria bait method. Among 210 soil samples, 168 fungal isolates were recovered and identified, with 98 from forests, 32 from vegetables, 30 from field crops and 8 from fruits. The major entomopathogenic fungi recovered from these samples were Beauveria bassiana, Metarhizium anisopliae, Paecilomyces lilacinus, B. brongniartii, P. chlamydosporia and Lecanicillium attenuatum. The diversity of entomopathogenic fungi was greater in soil samples from forests compared to crop fields, vegetables and fruits, respectively. The geographical attributes (altitude, longitude, latitude) greatly influenced the occurrence of entomopathogenic fungi with the highest number of isolates found from >600 m altitude, 33°–34′N latitude, and 73°74′E longitude from soil samples. The results of the surveys clearly indicated that the entomopathogenic fungi are distributed in the soils which may be used in successful IPM programs in future.     

Filamentous fungi from the Atlantic marine sponge Dragmacidon reticulatum

Dragmacidon reticulatum is a marine sponge of wide occurrence in the Eastern and Western Atlantic. Little is known about D. reticulatum fungal diversity. Filamentous fungi recovered from D. reticulatum were assessed in the present study using a polyphasic taxonomic approach, including classical morphology, molecular biology and MALDI-TOF ICMS. Ninety-eight fungal strains were isolated from two D. reticulatum samples by using six different culture media, which were identified up to the genus level. Sixty-four distinct fungal ribotypes were obtained, distributed among twenty-four different genera belonging to the Ascomycota and Zygomycota. Representatives of Penicillium and Trichoderma were the most diverse and abundant fungi isolated. Amongst Penicillium spp. three isolates belonged to the same ribotype can be considered as a putative new species. Data derived from the present study highlight the importance of using a polyphasic approach to get an accurate identification in order to structure a reliable culture collection.     

Open relationships in the castles of clay: high diversity and low host specificity of Termitomyces fungi associated with fungus-growing termites in Africa

In the African and Asian tropics, termites of the subfamily Macrotermitinae play a major role in the decomposition of dead plant material. Their ecological success lies in the obligate mutualism of the termites with fungi of the genus Termitomyces. Before the advent of molecular studies, the interaction with these fungi was poorly understood. Here, we combined available ITS sequence data from West, Central, and South Africa with data of 39 new samples from East Africa to achieve the most comprehensive view of the diversity and host specificity of Termitomyces symbionts across Africa to date. A high amount of sequence divergence in the ITS sequences was found; 11 different Termitomyces lineages in East Africa and >30 lineages across Africa were identified, and the expected diversity is estimated to be about 41 lineages. The fungal lineages belong to four major clades, each almost exclusively associated with one termite host genus. Analysis of molecular variance revealed that 40% of the ITS sequence variation occurred between host genera, indicating close co-evolution at this level. However, within host genera, fungal lineages and haplotypes were frequently shared among host species and sampling localities, except for fungal symbionts of Odontotermes. Horizontal transmission of fungal symbionts may facilitate the transfer of haplotypes and species among hosts. However, at present, we have little understanding of the maintenance of specificity at the genus level. Possible explanations range from substrate specificity of fungi to an active selection of fungi by termites.     

Fungal species residing in the sclerotia of <Emphasis Type="Italic">Polyporus umbellatus</Emphasis>

Sclerotia of Polyporus umbellatus is a traditional Chinese herb. The sclerotia can survive in soils for long time and their growth depends upon a symbiotic association with Armillariella mellea. But it is unclear whether other fungi reside or play a role in the sclerotia. In this study, wild sclerotial samples were collected from seven provinces, which span southwest to northeast China. A total of 148 fungal isolates were recovered from the sclerotia of P. umbellatus and classified into 19 morphological taxa. Seventeen belonged to five genera: Fusarium, Eurotium, Penicillium, Geomyces and Mucor. The fungi found within the sclerotia varied depending on the province from which they were collected. The possible role of these fungi is discussed.     

First Report on Mould and Mycotoxin Contamination of Pistachios Sampled in Algeria

Mycotoxin contamination of pistachios represents a serious food safety hazard. The aim of this study was to evaluate fungal contamination and aflatoxin (AF) and ochratoxin A (OTA) occurrence in pistachio sampled in Algeria and to study the mycotoxigenic capacities of the isolates. A total of 31 pistachio samples were collected from retail outlets from different regions of Algeria. The most frequently found fungi were Penicillium spp. (38%), Aspergillus section Nigri (30%) and A. flavus (22%). A total of 56.5% of A. flavus isolates were able to produce AFB₁ and AFB₂. No A. section Nigri uniseriate isolate was OTA producer, whereas OTA production capacity was detected in 33.3% of the A. section Nigri biseriate. At least one of the potentially ochratoxigenic species was found in 64.5% of samples. Despite the high number of pistachio samples containing AFs and OTA-producing isolates, only two samples contained AFs (always below the EU maximum tolerable level) and only one sample showed OTA contamination. This is the first report on the occurrence of toxigenic moulds and mycotoxins in pistachios from Algerian market.     

A survey of the aeromycota of Sydney and its correspondence with environmental conditions: grass as a component of urban forestry could be a major determinant

A comprehensive survey of airborne fungi has been lacking for the Sydney region. This study determined the diversity and abundance of outdoor airborne fungal concentrations in urban Sydney. Monthly air samples were taken from 11 sites in central Sydney, and culturable fungi identified and quantified. The genus Cladosporium was the most frequently isolated fungal genus, with a frequency of 78 % and a mean density of 335 CFU m^?3. The next most frequently encountered genus was Alternaria, occurring in 53 % of samples with a mean of 124 CFU m^?3. Other frequently identified fungi, in decreasing occurrence, were as follows: Penicillium, Fusarium, Epicoccum, Phoma, Acremonium and Aureobasidium. Additionally, seasonal and spatial trends of airborne fungi were assessed, with increases in total culturable fungal concentrations experienced in the summer months. The correspondence between a range of key environmental variables and the phenology of airborne fungal propagules was also examined, with temperature, wind speed and proximal greenspace having the largest influence on fungal propagule density. If the greenspace was comprised of grass, stronger associations with fungal behaviour were observed.     

Biodiversity and concentration of airborne fungi in a hospital environment

The biodiversity and concentration of airborne fungi were monitored over a period of 6 months in a special-care unit of a hospital. Air sampling was performed in a corridor that was also accessible to visitors and in an adjacent bone-marrow transplantation (BMT) unit using an air sampler and two isolation media. Altogether, 98 fungal species could be identified, among them Aspergillus fumigatus and A. terreus as well as 48 other species reported as potential pathogens. The average contamination values of the corridor air ranged from 124 to 485 cfu m⁻³. Neither the degree of fungal air contamination nor the species composition inside the special care unit differed from those found in the corridor. By means of data obtained with a light-activated sensor, a possible influence of human activities on diurnal changes of fungal propagule concentration was shown. This revised version was published online in July 2006 with corrections to the Cover Date.     

Arbuscular fungi and mycorrhizae (Glomales) of the Hel Peninsula,Poland

In the years 1985–1989, the occurrence of arbuscular fungi and mycorrhizae on the Hel Peninsula (Poland) was investigated with the help of 45 soil and root samples collected under 20 plant species of eight families. Except for Zea mays, the other plant species were from uncultivated sites. All soil samples contained spores of arbuscular fungi, of which about 45% were of the genus Glomus. Acaulospora spp. preferred members of the Cupressaceae. Spores of Gigaspora occurred rarely and only in two plant families. Glomus spp. were most frequently associated with plants of the Rosaceae, and species of Scutellospora were found at markedly higher frequencies among roots of plants of the Gramineae and Cupressaceae. A total of 29 spore-forming species and Glomus tenue (a fungus recognizable by its distinctive infections) were found. The most frequently recovered fungus, Glomus tenue, was present in roots of 56.8% of examined plants. Of the spore-forming fungi, the most frequently isolated spores were those of Scutellospora dipurpurascens, then Glomus constrictum, Acaulospora 61, and Glomus microcarpum. The overall spore density in examined samples averaged 99.8 in 100 g dry soil in the range 1 to 547, and was highest in a sample taken from around roots of Festuca arundinacea. The dominant fungi forming spores in sampled soils were Glomus constrictum, Glomus microcarpum, and Scutellospora dipurpurascens. The average species density was 3.9 in 100 g dry soil in the range 1 to 10, and was highest in Corynephorus canescens, Rosa canina, and Thuja occidentalis. Levels of colonization by arbuscular fungi ranged from 0.0 to94.0% (mean 23.3%) of the root length and were highest in Festuca arundinaceae and Zea mays.     

Investigation of keratinophilic fungi from soils in Western Australia a preliminary survey

In order to determine which species of geophilic dermatophytes were present in Western Australian soils 299 samples were investigated. These samples were collected from a range of locations, 208 from towns throughout the state and 91 samples from the Perth Metropolitan area.Most samples were collected from areas frequented by people and animals, such as home gardens, parks and animal yards.Of the total 299 soils, 271 (90.6 %) yielded keratinophilic fungi. A total of 181 dermatophytes were isolated, and there were 205 isolations of other keratinophilic fungi. Microsporum gypseum (30.7 %) was the most prevalent dermatophyte recovered from soil followed byMicrosporum cookei (21.7 %) and thenTrichophyton ajelloi (8.0 %). No other dermatophytes were recovered.Chrysosporium indicum was the most common of all the keratinophilic fungi and was isolated from 50.1 % of the samples. Mixed growth was obtained from 33.5 % of the soil samples.     

Phylogenetic diversity of culturable fungi associated with the Hawaiian Sponges Suberites zeteki and Gelliodes fibrosa

Sponges are well documented to harbor large amounts of microbes. Both culture-dependent and molecular approaches have revealed remarkable bacterial diversity in marine sponges. Fungi are commonly isolated from marine sponges, yet no reports on phylogenetic diversity of sponge-inhabiting fungi exist. In this report, we investigated the phylogenetic diversity of culturable fungi from the Hawaiian alien marine sponges Suberites zeteki and Gelliodes fibrosa. A total of 44 independent isolates were recovered from these two sponge species, representing 7 orders and 22 genera of Ascomycota. The majority (58%) of fungal isolates from S. zeteki resided in the Pleosporales group, while the predominant isolates (52%) from G. fibrosa were members of the Hypocreales group. Though differing in fungal species composition and structure, culturable communities of these two sponges displayed similar phylogenetic diversity. At the genus level, only two genera Penicillium and Trichoderma in the Eurotiales and Hypocreales orders, respectively, were present in both sponge species. The other genera of the fungal isolates were associated with either S. zeteki or G. fibrosa. Some of these fungal genera had been isolated from sponges collected in other marine habitats, but more than half of these genera were identified for the first time in these two marine sponges. Overall, the diversity of culturable fungal communities from these two sponge species is much higher than that observed in studies of marine sponges from other areas. This is the first report of phylogenetic diversity of marine sponge-associated fungi and adds one more dimension to our current understanding of the phylogenetic diversity of sponge-symbiotic microbes.