Halotolerant Ability and α-Amylase Activity of Some Saltwater Fungal Isolates

Four halotolerant fungal isolates originating from the saltwater Lake Urmia in Iran were selected during a screening program for salt resistance and α-amylase activity. The isolates were identified based on sequencing the ITS region and a part of the β-tubulin gene, as Penicillium chrysogenum (isolate U1; CBS 132820), Fusarium incarnatum (isolate U2; CBS 132821), and Penicillium polonicum (isolate U3; CBS 132822, and isolate U4; CBS 132823). The growth of these isolates was determined by measuring the colony diameter and mycelia dry weight in Sabouraud dextrose agar and yeast nitrogen base medium supplemented with NaCl, KCl, and LiCl. Isolate U4 showed a growth up in 15% NaCl and U1 was the only isolate that could grow in 20% KCl. None of the strains grew in a media containing LiCl. The salt supplemented medium did not increase the size of colony diameter in all isolates (p > 0.05). The ability of the selected isolates for amylase production was quantitatively tested and showed that P. polonicum isolate U4 was the most potent producer of amylase with a yield of 260.9 U/L after 60 h, whereas P. polonicum isolate U3 was the lowest one with a production level of 97.9 U/L after 48 h. P. polonicum isolate U4 could be a suitable candidate for production of amylase on an industrial scale after optimization. © 2013 by School of Pharmacy

Two novel <i>Aspergillus </i>species from hypersaline soils of The National Park of Lake Urmia, Iran

Two novel Aspergillus species, one belonging to the section Terrei and the other to section Flavipedes, were isolated from hypersaline soils of The National Park of Lake Urmia (Iran) and are here described as Aspergillus iranicus and Aspergillus urmiensis. A polyphasic taxonomic approach comprising extrolite profiles, phenotypic characters and molecular data (beta-tubulin, calmodulin and ribosomal polymerase II second largest subunit gene sequences) was applied to determine their novel taxonomic status. Aspergillus iranicus (CBS 139561T) is phylogenetically related to A. carneus, A. niveus, A. allahabadii and A. neoindicus, and it can be differentiated from those species by a unique extrolite pattern (citrinin, gregatins, and a terrequinone) and its conidial colour. Aspergillus urmiensis (CBS 139558T) shares a most recent common ancestor with A. templicola. The former species produces globose vesicles, and those of A. templicola are predominantly elongate. The Aspergillus urmiensis isolates produce several uncharacterized extrolites. Two other strains obtained during this study reside in a clade, together with the type strain of A. movilensis (CCF 4410T), and are identified accordingly. Based on the phylogenetic data presented in this study, A. frequens is reduced to synonymy with A. micronesiensis and A. mangaliensis is considered to be a synonym of A. templicola

Evaluation of 99 pesticide residues in major agricultural products from the Western Highlands zone of Cameroon using QuECHERS method extraction and LC-MS/MS and GC-ECD analyses

There is no information available on pesticide residue levels in major food commodities harvested in Cameroon, especially from the western highlands region, the food basket of the country. Hence, this study evaluated the residues of 99 pesticides in 72 samples of 12 agricultural products collected in the region, using QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) method extraction, and analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS) and gas chromatography with electron capture detection (GC-ECD). This method was suitable for detecting the targeted compounds: For 81 pesticides by LC-MS/MS, the limit of quantification (LOQ) was between 0.0004 and 0.0537 mg/kg; and for 18 halogenated pesticides by GC-ECD, it ranged from 0.0012 to 0.2180 mg/kg. The residues of 62 pesticides, including 12 banned compounds, were found in the samples. Insecticides (39.7%) were the most prevalent group, with all the samples containing at least one pesticide. Twenty-one pesticides (34.4%) exceeded their European Union maximum residue limits (MRLs) and 22 pesticides (34.4%) were found in all 6 sampling locations. Malathion and p,p′-DDT were the most distributed pesticides, found in almost all the samples and sampling sites. Food items with the highest rates of positive results were chili pepper (23.2%), white pepper (20.2%), kidney beans (17.3%), and soybeans (17.2%). Samples with residues above their MRLs represented 38% of all the positive analyses; chili pepper (6.4%) and kidney beans (5.5%) were found to have the most residues above their MRLs. The most critical food commodities were kidney beans, soybeans, chili pepper, and maize. This data presents scientific evidence that investigation into continuous monitoring and good regulation of pesticide usage in Cameroon is needed, and paves the way for health risks analysi

Occurrence of Unapproved Pesticides and their Ecotoxicological Significance for an Agriculturally Influenced Reservoir and its Tributaries in Nepal

Many catchments in Nepal are affected by intensive agricultural activities, leading to extensive pesticide usages. This study aimed to assess pesticide abundance in concurrently collected water, sediment and fish samples for the first time in intensively cultivated catchment (Indra Sarowar) located in the mid-hill region of Nepal during the rice and vegetables growing season. A total of 75 pesticides were analysed, of which 4 pesticides (alachlor, diuron, metalaxyl and pyrimethanil) were present in water with detection frequency (DF) > 40%, with alachlor (0.62 – 2.68 µg L−1) being ubiquitous. In the sediment of tributaries, the pesticides p,p′-DDT, β-HCH, alachlor and diuron were detected with DF exceeding 40%, where β-HCH was commonly observed (DF = 92%) with concentration ranging from 6.29 – 99.22 µg kg−1. The ecotoxicological risk indicated that herbicides (alachlor and diuron) posed a high risk to aquatic organisms in both tributaries and reservoir water. Such risk in sediment was even more pronounced, with alachlor and diuron showing up to 2.3 and 53.7 times higher risk respectively compared to water samples. However, none of these herbicides were detected in fish muscles. Among the fish species studied, pyrimethanil was the only quantified pesticide in edible tissue of both cage cultured (0.35 – 1.80 µg g−1 ww) and open stock fishes (0.06 – 1.12 µg g−1 ww). The consumer risk assessment showed very low human health risk associated with fish consumption (HQ < 0.2). Nonetheless, long-term consumption of contaminated fish may pose some risk that cannot be ignored. Overall, this study generated the benchmark data highlighting pervasive presence of banned (DDT, endosulfan, HCH) and unapproved (alachlor, diuron, pyrimethanil) pesticides in the environmental compartments in the mid-hill’s streams of Nepal

Delimitation and characterisation of Talaromyces purpurogenus and related species

Taxa of the Talaromyces purpurogenus complex were studied using a polyphasic approach. ITS barcodes were used to show relationships between species of the T. purpurogenus complex and other Talaromyces species. RPB1, RPB2, β-tubulin and calmodulin sequences were used to delimit phylogenetic species in the complex. These data, combined with phenotypic characters, showed that the complex contains four species: T. purpurogenus, T. ruber comb. nov. and two new species T. amestolkiae sp. nov. and T. stollii sp. nov. The latter three species belong to the same clade and T. purpurogenus is located in a phylogenetic distant clade. The four species all share similar conidiophore morphologies, but can be distinguished by macromorphological characters. Talaromyces ruber has a very distinct colony texture on malt extract agar (MEA), produces bright yellow and red mycelium on yeast extract sucrose agar (YES) and does not produce acid on creatine sucrose agar (CREA). In contrast, T. amestolkiae and T. stollii produce acid on CREA. These two species can be differentiated by the slower growth rate of T. amestolkiae on CYA incubated at 36 °C. Furthermore, T. stollii produces soft synnemata-like structures in the centre of colonies on most media. Extrolite analysis confirms the distinction of four species in the T. purpurogenus complex. The red diffusing pigment in T. purpurogenus is a mixture of the azaphilone extrolites also found in Monascus species, including N-glutarylrubropunctamine and rubropunctatin. Talaromyces purpurogenus produced four different kinds of mycotoxins: rubratoxins, luteoskyrin, spiculisporic acid and rugulovasins and these mycotoxins were not detected in the other three specie

Diversity and taxonomy of Chaetomium and chaetomium-like fungi from indoor environments

During a study of indoor fungi, 145 isolates belonging to Chaetomiaceae were cultured from air, swab and dust samples from 19 countries. Based on the phylogenetic analyses of DNA-directed RNA polymerase II second largest subunit (rpb2), β-tubulin (tub2), ITS and 28S large subunit (LSU) nrDNA sequences, together with morphological comparisons with related genera and species, 30 indoor taxa are recognised, of which 22 represent known species, seven are described as new, and one remains to be identified to species level. In our collection, 69 % of the indoor isolates with six species cluster with members of the Chaetomium globosum species complex, representing Chaetomium sensu stricto. The other indoor species fall into nine lineages that are separated from each other with several known chaetomiaceous genera occurring among them. No generic names are available for five of those lineages, and the following new genera are introduced here: Amesia with three indoor species, Arcopilus with one indoor species, Collariella with four indoor species, Dichotomopilus with seven indoor species and Ovatospora with two indoor species. The generic concept of Botryotrichum is expanded to include Emilmuelleria and the chaetomium-like species B. muromum (= Ch. murorum) in which two indoor species are included. The generic concept of Subramaniula is expanded to include several chaetomium-like taxa as well as one indoor species. Humicola is recognised as a distinct genus including two indoor taxa. According to this study, Ch. globosum is the most abundant Chaetomiaceae indoor species (74/145), followed by Ch. cochliodes (17/145), Ch. elatum (6/145) and B. piluliferum (5/145). The morphological diversity of indoor Chaetomiaceae as well as the morphological characteristics of the new genera are described and illustrated. This taxonomic study redefines the generic concept of Chaetomium and provides new insight into the phylogenetic relationships among different genera within Chaetomiaceae

Aspergillus felis sp. nov., an emerging agent of invasive aspergillosis in humans, cats, and dogs

Published June 14, 2013We describe a novel heterothallic species in Aspergillus section Fumigati, namely A. felis (neosartorya-morph) isolated from three host species with invasive aspergillosis including a human patient with chronic invasive pulmonary aspergillosis, domestic cats with invasive fungal rhinosinusitis and a dog with disseminated invasive aspergillosis. Disease in all host species was often refractory to aggressive antifungal therapeutic regimens. Four other human isolates previously reported as A. viridinutans were identified as A. felis on comparative sequence analysis of the partial β-tubulin and/or calmodulin genes. A. felis is a heterothallic mold with a fully functioning reproductive cycle, as confirmed by mating-type analysis, induction of teleomorphs within 7 to 10 days in vitro and ascospore germination. Phenotypic analyses show that A. felis can be distinguished from the related species A. viridinutans by its ability to grow at 45°C and from A. fumigatus by its inability to grow at 50°C. Itraconazole and voriconazole cross-resistance was common in vitro.Vanessa R. Barrs, Tineke M. van Doorn, Jos Houbraken, Sarah E. Kidd, Patricia Martin, Maria Dolores Pinheiro, Malcolm Richardson, Janos Varga, Robert A. Samso

Recommendations to prevent taxonomic misidentification of genome-sequenced fungal strains

Correct identification of a (genome-sequenced) strain is an essential step in evolutionary and comparative genomic studies. It came to our attention that the number of publicly available misidentified genome-sequenced strains is increasing. By using the order Eurotiales (Aspergillus, Penicillium, Talaromyces, and related genera) as an example, in this letter we want to increase awareness among readers of Microbiology Resource Announcements of this ongoing problem and give recommendations to ensure availability and correct strain identification in the future.https://mra.asm.org/https://mra.asm.orgam2022BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant Patholog