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Benzene, toluene, ethylbenzene, and xylene (BTEX) can be found in marine and estuarine waters due to accidental spills of oil and derivatives, as well as in production water and effluents discharged from petrochemical plants. Addressing the bioremediation of these compounds in saline environments and effluents with elevated salinity levels is imperative. In this study, the halotolerance of Aspergillus niger was assessed by subjecting it to a stepwise increase in salinity, achieved through progressive addition of NaCl from 2 to 30‰ (v/v). The fungal strain exhibited optimal growth support up to a salinity concentration of 25‰, accompanied by a biomass production rate of (0.93 ± 0.11) g.d-1. The adapted biomass was employed in batch reactors to evaluate the biodegradation of BTEX (1,500 mg.L-1). In the absence of sucrose, the reactors inoculated with fungi demonstrated almost complete BTEX removal within 7 days, with rates ranked as follows: benzene (1.12 d-1) > toluene (0.78 d-1) > ethylbenzene (0.65 d-1) > xylene (0.63 d-1). Enhanced BTEX removal rates were obtained in the presence of sucrose, notably with 2 g.L-1: benzene (3.63 d-1) > toluene (2.10 d-1) > ethylbenzene (1.56 d-1) > xylene (1.50 d-1). Notably, benzene was found to be the sole compound adsorbed onto the fungal mycelium (1.50 ± 0.19) to (13.35 ± 4.72) mg.g-1 of biomass. [ABSTRACT FROM AUTHOR]

The pressing demand for novel compounds to address contemporary health challenges has prompted researchers to venture into uncharted territory, including extreme ecosystems, in search of new natural pharmaceuticals. Fungi capable of tolerating extreme conditions, known as extremophilic fungi, have garnered attention for their ability to produce unique secondary metabolites crucial for defense and communication, some of which exhibit promising clinical significance. Among these, halophilic fungi thriving in high-salinity environments have particularly piqued interest for their production of bioactive molecules. This review highlights the recent discoveries regarding novel compounds from halotolerant fungal strains isolated from various saline habitats. From diverse fungal species including Aspergillus, Penicillium, Alternaria, Myrothecium, and Cladosporium, a plethora of intriguing molecules have been elucidated, showcasing diverse chemical structures and bioactivity. These compounds exhibit cytotoxicity against cancer cell lines such as A549, HL60, and K-562, antimicrobial activity against pathogens like Escherichia coli, Bacillus subtilis, and Candida albicans, as well as radical-scavenging properties. Notable examples include variecolorins, sclerotides, alternarosides, and chrysogesides, among others. Additionally, several compounds display unique structural motifs, such as spiro-anthronopyranoid diketopiperazines and pentacyclic triterpenoids. The results emphasize the significant promise of halotolerant fungi in providing bioactive compounds for pharmaceutical, agricultural, and biotechnological uses. However, despite their potential, halophilic fungi are still largely unexplored as sources of valuable compounds. [ABSTRACT FROM AUTHOR]

We have performed a characterization of cultivated haloalkalitolerant fungi from the sediments of Big Tambukan Lake in order to assess their biodiversity and antimicrobial activity. This saline, slightly alkaline lake is known as a source of therapeutic sulfide mud used in sanatoria of the Caucasian Mineral Waters, Russia. Though data on bacteria and algae observed in this lake are available in the literature, data on fungi adapted to the conditions of the lake are lacking. The diversity of haloalkalitolerant fungi was low and represented by ascomycetes of the genera Acremonium, Alternaria, Aspergillus, Chordomyces, Emericellopsis, Fusarium, Gibellulopsis, Myriodontium, Penicillium, and Pseudeurotium. Most of the fungi were characterized by moderate alkaline resistance, and they tolerated NaCl concentrations up to 10% w/v. The analysis of the antimicrobial activity of fungi showed that 87.5% of all strains were active against Bacillus subtilis, and 39.6% were also determined to be effective against Escherichia coli. The majority of the strains were also active against Aspergillus niger and Candida albicans, about 66.7% and 62.5%, respectively. These studies indicate, for the first time, the presence of polyextremotolerant fungi in the sediments of Big Tambukan Lake, which probably reflects their involvement in the formation of therapeutic muds. [ABSTRACT FROM AUTHOR]

We have performed a characterization of cultivated haloalkalitolerant fungi from the sediments of Big Tambukan Lake in order to assess their biodiversity and antimicrobial activity. This saline, slightly alkaline lake is known as a source of therapeutic sulfide mud used in sanatoria of the Caucasian Mineral Waters, Russia. Though data on bacteria and algae observed in this lake are available in the literature, data on fungi adapted to the conditions of the lake are lacking. The diversity of haloalkalitolerant fungi was low and represented by ascomycetes of the genera Acremonium, Alternaria, Aspergillus, Chordomyces, Emericellopsis, Fusarium, Gibellulopsis, Myriodontium, Penicillium, and Pseudeurotium. Most of the fungi were characterized by moderate alkaline resistance, and they tolerated NaCl concentrations up to 10% w/v. The analysis of the antimicrobial activity of fungi showed that 87.5% of all strains were active against Bacillus subtilis, and 39.6% were also determined to be effective against Escherichia coli. The majority of the strains were also active against Aspergillus niger and Candida albicans, about 66.7% and 62.5%, respectively. These studies indicate, for the first time, the presence of polyextremotolerant fungi in the sediments of Big Tambukan Lake, which probably reflects their involvement in the formation of therapeutic muds.

Marine-derived fungi are of great interest as a new promising source of biologically active products such as anticancer compounds, antibiotics, inhibitors of biochemical processes. Since marine organisms inhabit biologically competitive environment with unique conditions, the chemical diversity of the secondary metabolites from marine fungi is considerably high. Recent genomic studies demonstrated that fungi can carry gene clasters encoding production of previously unknown secondary metabolites. Activation of the attenuated or silent genes would be useful either for improving activities of the known compounds or for discovery of new products.

Most of the rock-inhabiting fungi are meristematic and melanized microorganisms often associated with monument biodeterioration. In previous microbial profiling of the Egyptian Djoser pyramid, a Pseudotaeniolina globosa isolate was found. The current study aimed to characterize the P. globosa isolated from the Djoser pyramid compared with an Italian isolate at morphological, physiological, and molecular levels. Experiments were carried out to test temperature, salinity, and pH preferences, as well as stress tolerance to UV radiation and high temperature, in addition to a multilocus genotyping using ITS, nrSSU or 18S, nrLSU or 28S, BT2, and RPB2 markers. Morphological and molecular data confirmed the con-specificity of the two isolates. However, the Egyptian isolate showed a wider range of growth at different environmental conditions being much more tolerant to a wider range of temperature (4–37 ◦C) and pH values (3.0–9.0 pH) than the Italian (10–30 ◦C, 4.0–6.0 pH), and more tolerant to extreme salinity levels (5 M NaCl), compared to the lowest in the Italian isolate (0.2 M NaCl). Besides, the Egyptian isolate was more tolerant to high temperature than the Italian isolate since it was able to survive after exposure to up to 85 ◦C for 5 min, and was not affected for up to 9 h of UV exposure, while the Italian one could not regrow after the same treatments. The Pseudotaeniolina globosa species was attributed to the family Teratosphaeriaceae of the order Capnodiales, class Dothideomycetes. Our results demonstrated that the Egyptian isolate could be considered an ecotype well adapted to harsh and extreme environments. Its potential bio-deteriorating effect on such an important cultural heritage requires special attention to design and conservation plans and solutions to limit its presence and extension in the studied pyramid and surrounding archaeological sites. [ABSTRACT FROM AUTHOR]

Aims: Sustainable agriculture requires effective and safe biofertilizers and biofungicides with low environmental impact. Natural ecosystems that closely resemble the conditions of biosaline agriculture may present a reservoir for fungal strains that can be used as novel bioeffectors. Methods and Results: We isolated a library of fungi from the rhizosphere of three natural halotolerant plants grown in the emerging tidal salt marshes on the south‐east coast of China. DNA barcoding of 116 isolates based on the rRNA ITS1 and 2 and other markers (tef1 or rpb2) revealed 38 fungal species, including plant pathogenic (41%), saprotrophic (24%) and mycoparasitic (28%) taxa. The mycoparasitic fungi were mainly species from the hypocrealean genus Trichoderma, including at least four novel phylotypes. Two of them, representing the taxa Trichoderma arenarium sp. nov. (described here) and T. asperelloides, showed antagonistic activity against five phytopathogenic fungi, and significant growth promotion on tomato seedlings under the conditions of saline agriculture. Conclusions: Trichoderma spp. of salt marshes play the role of natural biological control in young soil ecosystems with a putatively premature microbiome. Significance and Impact of the Study: The saline soil microbiome is a rich source of halotolerant bioeffectors that can be used in biosaline agriculture. [ABSTRACT FROM AUTHOR]

Introduction: Biodegradation of hydrocarbons in the saline environment is diminished due to the reduced solubility of hydrocarbons and oxygen and lower microbial diversity because of inhibitory effect of salt. Materials and methods: In this research, fungi isolation was carried out from salty oil contaminated soil from different parts of Iran. Then, the ability of crude oil degradation was measured for each isolate in the presence of 50 g/l NaCl by total petroleum hydrocarbon (TPH) assay. The salt tolerance and crude oil degradation capacity of the selected isolate was evaluated in medium containing different salt concentration by analysis of TPH, FTIR and dried cell weight assay. Finally, the selected isolate was studied for biosurfactant production and identified using morphological and molecular approach. Results: In this study, 15 different halotolerant fungal species were isolated. TPH assay in medium containing crude oil (1%) and salt (50 g/l) showed that the isolate S-05 with 60 % oil removal was the best strain. FTIR analysis revealed that 90% of aliphatic compounds were removed when treated with S-05. Biosurfactant production assay indicated that this strain can produce surface active compounds in presence and absence of salt. Molecular identification confirmed that the S-05 belongs to Mucor circinelloides with 100% similarity. Discussion and conclusion: Our results indicate that M. circinelloides UTMC 5032 is potent fungus for bioremediation in saline oil contaminated soils.

Exposure of microorganisms to stress, including to high concentrations of salt, can lead to increased production of reactive oxygen species in the cell. To limit the resulting damage, cells have evolved a variety of antioxidant defenses. The role of these defenses in halotolerance has been proposed before. Whole genome sequencing for some of the most halotolerant and halophilic fungal species has enabled us to investigate the possible links between oxidative and salt stress tolerance on the genomic level. We identified genes involved in oxidative stress response in the halophilic basidiomycete Wallemia ichthyophaga, and halotolerant ascomycetous black yeasts Hortaea werneckii and Aureobasidium pullulans, and compared them to genes from 16 other fungi, both asco- and basidiomycetes. According to our results, W. ichthyophaga can survive salinities detrimental to most other organisms with only a moderate number of oxidative stress response genes. In other investigated species, however, the maximum tolerated salinity correlated with the number of genes encoding three major enzymes of the cellular oxidative stress response: superoxide dismutases, catalases, and peroxiredoxins. This observation supports the hypothetical link between the antioxidant capacity of cells and their halotolerance. [ABSTRACT FROM AUTHOR]

Introduction: Biodegradation of hydrocarbons in the saline environment is diminished due to the reduced solubility of hydrocarbons and oxygen and lower microbial diversity because of inhibitory effect of salt. Materials and methods: In this research, fungi isolation was carried out from salty oil contaminated soil from different parts of Iran. Then, the ability of crude oil degradation was measured for each isolate in the presence of 50 g/l NaCl by total petroleum hydrocarbon (TPH) assay. The salt tolerance and crude oil degradation capacity of the selected isolate was evaluated in medium containing different salt concentration by analysis of TPH, FTIR and dried cell weight assay. Finally, the selected isolate was studied for biosurfactant production and identified using morphological and molecular approach. Results: In this study, 15 different halotolerant fungal species were isolated. TPH assay in medium containing crude oil (1%) and salt (50 g/l) showed that the isolate S-05 with 60 % oil removal was the best strain. FTIR analysis revealed that 90% of aliphatic compounds were removed when treated with S-05. Biosurfactant production assay indicated that this strain can produce surface active compounds in presence and absence of salt. Molecular identification confirmed that the S-05 belongs to Mucor circinelloides with 100% similarity. Discussion and conclusion: Our results indicate that M. circinelloides UTMC 5032 is potent fungus for bioremediation in saline oil contaminated soils. [ABSTRACT FROM AUTHOR]

Materials and methods: Nine fungal isolates namely Emericill anidulans, Mucor racemosus , Alternaria pluriseptata Penicillium canescens, Syncephalastrum racemosum, Aspergillus fumigatus, Alternaria chlamydospora, Aspergillus parasiticus and Ulocladium atrum were isolated from AL-SHEGA area at AL- QASSIM region. Results: The influence of different sodium chloride concentrations on the growth rate, morphological and ultrastructure were studied. Considerable differences in their growth rate and morphology were detected on medium containing different concentrations of sodium chloride (NaCl). Low growth rates were obseved on high NaCl concentrations . At 15 % NaCl, low growth of Emericill anidulans, Penicillium canescens, Syncephalastrum racemosum, Aspergillus parasiticus and Mucor racemosus was detected , whereas all fungal isolates were failed to grow at 20% NaCl. Scanning Electron Microscope (SEM) revealed that all fungal asexual reproduction organs were metamorphosed at higher NaCl concentration, fungal heads and sporangia were speculated or elongated. Sporangiophores and conidiophores were shortened and dwarfed ,little number of conidia or spores were detected. [ABSTRACT FROM AUTHOR]

A total of 17 species from 43 isolates were obtained through serial dilutions of soil samples isolated from one of the man-made solar salterns located in Ban Laem district of Phetchaburi province, Thailand. Soil analysis of the sample revealed high salinity and moisture content, slight alkalinity and low amounts of nitrogen, total organic carbon and organic matter in the habitat. Morphological analysis was performed on all isolates, and molecular identification and phylogenetic analysis were carried out only on the halophilic fungi isolated. Six halophilic fungi, belonging to four species, were identified among the isolates, including five strains of Aspergillus genus [ Aspergillus flavus, A. gracilis, A. penicillioides (2 strains) and A. restrictus]. One species was found to be a yeast, namely, Sterigmatomyces halophilus, which was the most frequent isolate found among the halophilic fungi. All other isolates were halotolerant fungi. Characterization of the halophilic fungal isolates showed that they were best adapted to conditions of 10-15 % NaCl (w/v), slight alkalinity (pH 7.0-7.5) and a temperature range of 30-35 °C. [ABSTRACT FROM AUTHOR]

Abstract: The main aim of this study was to assess the ability of producing extracellular phenoloxidases (EPO) of fungi isolated from olive brine wastewater (OBW), the effluent from the debittering process of table olives. Five out of twenty isolates displayed EPO-producing ability as assessed by selective agar plate assays and were all halotolerant. Among them, Citeromyces matritensis (syn. Candida globosa) and Aspergillus fumigatus concomitantly produced laccase and Mn-peroxidase (MnP) activities. Candida boidinii and Candida bombi, instead, only produced laccase and Candida diddensiae only released MnP. Both C. matritensis and A. fumigatus, grown in shaken cultures on OBW, maintained their EPO-producing ability and removed phenols by 52.3 and 82.3%, respectively, after 10d incubation in the non-supplemented effluent. These results might suggest the possible use of these strains in the treatment of other saline phenol-rich effluents, such as pickling and tannery wastewater. [Copyright &y& Elsevier]

Periconia variicolor was isolated from water of an evaporation pond used for salt production on the southwestern coast of Puerto Rico. On the basis of cultural and morphological characteristics and ITS sequence it is describe as a new species of Periconia. [ABSTRACT FROM AUTHOR]

Abstract: The Cabo Rojo Solar Salterns located on the southwest coast of Puerto Rico are composed of two main ecosystems (i.e., salt ponds and microbial mats). Even though these locations are characterized by high solar radiation (mean light intensity of 39mol photons m−2 d−1) they harbour a diverse microscopic life. We used morphological and molecular techniques to identify a series of halotolerant fungi. A total of 183 isolates and 36 species were cultured in this study. From the water from the salt ponds, 86 isolates of 26 species were cultured. The halotolerant fungi isolated from water were: Cladosporium cladosporioides, nine Aspergillus sp., five Penicillium sp. and the black yeast Hortaea werneckii. A distinctive isolate with a blue mycelium was cultured from the salt ponds, representing a new species of Periconia based on morphology and rDNA analysis. Forty-four isolates from eight species were cultured from the sediments around the salt ponds. Most of the sediment isolates formed only sterile mycelium, while several were Chaetomium globosum. A total of 53 isolates from 16 species were isolated from the three layers of the microbial mats, of which Aspergillus niger was the most frequent isolate. Phospholipid fatty acid profiles generated from the different layers of the microbial mats indicated that the uppermost layers of the mats contained fungal biomarker, 18:2w6. This fatty acid decreased with depth, the highest concentration was observed in the green upper layer and it disappeared in the black bottom anoxic layer. This correlates with the isolation of fungi using the serial dilution technique. This is the first study that documents the presence of fungi in microbial mats. [Copyright &y& Elsevier]