Synergistic interactions between Stachybotrys chartarum and other indoor fungal species in moisture-damaged houses

The interactions between six commonly occurring fungal species in damp or water-damaged houses in southern California were studied. These fungal species were Alternaria alternata, Aspergillus niger, Chaetomium globosum, Cladosporium herbarum, Penicillium chrysogenum and Stachybotrys chartarum. In the damp building materials, S. chartarum was found to be associated with A. niger, C. globosum, and P. chrysogenum but not with A. alternata and C. herbarum. Stachybotrys chartarum showed strong antagonistic effect against A. alternata and C. herbarum and significantly inhibited in vitro growth of A. alternata and C. herbarum but had no effect on A. niger, C. globosum, and P. chrysogenum. Two trichothecenes, produced by S. chartarum, trichodermin and trichodermol, significantly inhibited spore germination and in vitro growth of A. alternata and C. herbarum but had no effect on A. niger, C. globosum, P. chrysogenum and S. chartarum. In the damp building materials (drywall, ceiling tile, and oak woods), S. chartarum significantly inhibited the growth of A. alternata and C. herbarum and had no effect on the growth and colonization of A. niger, C. globosum, P. chrysogenum in these substrata.

Bioatividade do óleo essencial de Eugenia caryophyllus sobre Cladosporium herbarum, agente etiológico da verrugose em maracujá

Os óleos essenciais extraídos de plantas exibem funções ecológicas importantes demonstradas através de diversos estudos, com potencial para serem utilizados como agentes antimicrobianos naturais em substituição aos pesticidas convencionais. O objetivo deste estudo foi avaliar in vitro a fungitoxidade do óleo essencial de Eugenia caryophyllus Tumb, em diferentes concentrações, contra o crescimento micelial de Cladosporium herbarum, agente etiológico da doença conhecida como “verrugose” que afeta todos os órgãos aéreos do maracujazeiro, reduzindo seriamente a produtividade, o suprimento, os preços e a qualidade da fruta. A partir de frutos e flores, o fungo foi isolado, recuperado e analisado em batata-dextrose-ágar (BDA) com os tratamentos 12,8; 6,4; 3,2; 1,6; 0,8; 0,4 e 0,2 μL de óleo essencial de E. caryophyllus. O óleo essencial de E. caryophyllus inibiu o crescimento micelial de C. herbarum a partir da concentração de 1,6 μL e apresentou uma inibição micelial total na concentração de 12,8 μL. Assim, o óleo essencial de E. caryophyllus apresentou-se promissor para aplicações futuras como agente biofungicida contra C. herbarum.

Microbial Degradation of Ancient Wood Housed in Cheops Boat Museum and Methods of Its Control

The present research paper aims to determine the effect of microbial deterioration on wood housed in Cheops Boat and how to control it. Khufu, the second king of the Fourth Dynasty 2650 BC, established Cheops Boat that was found in 1954 on the southern side of the pyramid. Wood is usually very sensitive to biological attacks. Therefore, fungi, bacteria, and insects can easily attack and metabolize it, leading to significant physical, chemical, and morphological changes. Cellulose agar was used for the cultivation of fungi, and nutrient agar was used to cultivate bacteria. Microbial infections were identified using light microscopy and PCR after their cultivation. The causative microorganisms were isolated from Cheops Boat and characterized as A. niger, A. flavus, A. sulphureus, P. janthinellum, Cladosporium herbarum, Botryotrichum piluliferum, and Bacillus megaterium. The characteristics of the test methods and disinfection include their application to historical objects. Historic wood was analyzed from different perspectives: Stereo microscopes, SEM with EDX, FTIR, as well as wood structure and chemical composition. The biological activities of the isolated microorganisms were studied. The results illustrated that the best concentrations of a specific microbicide for the bio-treatment of the infected wood materials is pentachlorophenol at (900 ppm) as it is sufficient to inhibit all isolated microorganisms. It is followed by plant extract of Ceratophyllum demersum at (1000 ppm) concentration, and p-chloro-m-cresol at (2000 ppm) concentration.

Taxonomic analysis of soil phytopathogenic mycocomplexes of different varieties of faba beans in the Central Black Earth Region of the Russian Federation

The species composition and structure of soil complexes of micromycetes under faba beans were studied. The indices of the frequency of occurrence and abundance of microscopic fungi species in soils under ten varieties of faba beans were analyzed in comparison with the control soil (pure fallow). The control revealed 20 species of micromycetes from 10 genera. The species from 16 genera were identified under the varieties of beans in the soils. Most micromycetes belong to the Ascomycota division (classes Dothideomycetes, Eurotiomycetes, Saccharomycetes, and Sordariomycetes). In the soil of faba beans, the number of micromycete propagules is significantly higher (30.6 ± 2.5 thousand CFU / g soil) than in the control (12.5 ± 2.3 thousand CFU / g). The biodiversity of micromycete complexes in the control soil was maximal (Pielu index 0.75). An increase in the dominance index under the studied varieties of beans (Simpson’s index 0.09-0.24) was noted in comparison with the control soil, with a dominance index of 0.07. Phytopathogenic species of micromycetes were found: fungi Ascochyta fabaе, Alternaria tenuissima, Cladosporium herbarum, Fusarium culmorum, F. oxysporum, F. solani, and Ulocladium botrytis.

MICROBIAL COMMUNITY OF THE ASKINSKAYA CAVE

The cave Askinskaya (Askynskaya, Ledyanaya) contains the largest perennial hydrogenic ice in the territory of the Southern Urals. It is shown that the soil and horizontal hydrogenic ice are the main reservoirs for storing microorganisms in the cave, and the microbial pool is replenished mainly due to recreational load, but natural ways – rain, melt water and air from the surface also make a certain contribution. From all the ecotopes of the cave (soil, water occurrences, rock surfaces and aerial environment), 72 species of microscopic fungi (D – 0.69), sterile forms and yeast were isolated. Yeast fungi and species of Geomyces pannorum (d – 0.83), Acremonium charticola, Cladosporium herbarum, Penicillium aurantiuogriseum were found in all ecological niches with a high frequency of abundance / occurrence. The greatest variety of microscopic fungi is observed in the air (57 species), most species are introduced from the surface, settle on walls, ice, soil and, due to low temperatures, retain their viability in the cavity for a long time.

Cladosporium herbarum peptidogalactomannan triggers significant defense responses in whole tobacco plants

Cladosporium herbarum is one of the most frequently occurring fungal species, with a worldwide distribution, and is found in almost all man-occupied niches in organic and inorganic matter and as a phytopathogen on certain agricultural crops. The structure of the most abundant glycoprotein from the C. herbarum cell wall, peptidogalactomanann or pGM, was previously elucidated and includes carbohydrates (76%), with mannose, galactose and glucose as its main monosaccharides (52:36:12 molar ratio). pGM was able to strongly induce the expression of defense-related genes and ROS accumulation when in contact with BY2 tobacco cells. Here, using two distinct Nicotiana tabacum cultivars, Xanthi and SR1, we evaluated the ability of C. herbarum pGM to induce SAR-like defense by studying its antiviral activity against Tobacco mosaic virus (TMV) and the induction of SAR markers including PR genes and ROS accumulation. Our results show that pGM induced a strong activation of defense responses in treated plants from both tobacco cultivars, contributing to the impairment of viral infection. Expression levels of the pathogenesis-related genes PR-1a (unknown function), PR-2 (□-1-3 endoglucanase) PR-3 (chitinase), and PR-5 (thaumatin-like protein), the phenylpropanoid pathway gene PAL (phenylalanine ammonia-lyase) and genes involved in plant stress responses and innate immunity, such as LOX1 (lipoxygenase) and NtPrxN1 (peroxidase), were strongly induced until 120 h after pGM spray application. Accumulation of superoxide radicals was also observed in a pGM dose-dependent manner.

Antimicrobial Activity of Chrysoeriol 7 and Chochlioquinone 9, White-Backed Planthopper-Resistant Compounds, Against Rice Pathogenic Strains

As environmental damage caused by chemical pesticides appears worldwide, eco-friendly agriculture is increasing, and finding eco-friendly pesticide materials has become very important. Chrysoeriol and cochlioquinone, two flavonoids, act as an antibacterial and antioxidant, and increase the resistance of rice to the white-backed planthopper (WBPH). In this experiment, chrysoeriol 7 (C7) and cochlioquinone 9 (C9) were extracted from rice inoculated with the WBPH using MeOH, and cultivars with high extraction efficiency were selected. In addition, the antimicrobial activity of C7 and C9 against various pathogens causing disease in rice was tested. The results show that C7 has antifungal activity against Fusarium graminearum and Pythium graminicola, and C9 show antifungal activity against Cladosporium herbarum, Cladosporium cladosporioides, Gibberella zeae, Fusarium graminearum and Pythium graminicola. When both substances were treated at a concentration of 1000 ppm, they showed high inhibition rates of 62.3% and 36.2% against P.graminicola, respectively. After that, a phylogenetic tree was created to clarify the relationship between the microorganisms whose growth was inhibited and divided into three groups. This result can contribute to the study of biopesticide materials that can control pests and pathogens.

Sensitization to fungal allergens in patients with respiratory allergy – accuracy in diagnostic process

Introduction. In Bulgaria, mold allergies are common, and sensitization to different fungal species is found in many patients with atopy.The objective of this study is to explore sensitization to the most widespread mold species in Bulgaria, and to determine the extent of sensitization to Alt a1, a major allergen of Alternaria alternata, by using component-resolved diagnosis.Materials and Methods. 21 patients (14 males and 7 females, age range 5-40 years), with respiratory allergy participated in the study. All patients are sensitized to mix of fungal allergens containing: Alternaria alternata, Aspergillus sp., Cladosporium herbarum, Penicillium notatum, proved by in vivo and in vitro methods. All patients underwent the ImmunoCAP test and were assessed for sIgE to individual fungal allergens: m1 Penicillium notatum, m2 Cladosporium herbarum, m3 Aspergillus fumigatus and m6 Alternaria alternata. The component-resolved diagnosis to Alt a1 was performed for 10 patients with increased sIgE to m6 Alternaria alternata.Results. All studied patients (100%) had elevated sIgE to Alternaria alternata. Eight (38%) patients were sensitized to Penicillium notatum. 11 (52%) and 10 (48%) patients were sensitized to Cladosporium herbarum and to Aspergillus fumigatus, respectively. Ten patients (48%) were monosensitized to Alternaria alternata. Nine (90%) patients with sensitization to Alternaria alternata demonstrated elevated levels of IgE to Alt a1.Conclusion. Alternaria alternata most often causes sensitization in patients with respiratory allergy. The component-resolved diagnosis using Alt a1 is a precision marker to prove species-specific sensitization to Alternaria alternata.

Cladosporium herbarum Hot-Tub Lung Hypersensitivity Pneumonitis in a Greenhouse Worker

Hypersensitivity pneumonitis is understood to be a delayed allergic reaction to the repeated exposure of a usually innocent inhaled agent, causing inflammatory damage to the pulmonary parenchyma, alveoli and terminal bronchioles. With ongoing exposure, it can cause respiratory compromise and pulmonary fibrosis. Recognizing the heterogeneity of the causative agents and the low incidence of the disease, we considered it important to report the case of a greenhouse worker who developed aCladosporium sp. related hot-tub lung hypersensitivity pneumonitis. We believe it to be the first reported case of a greenhouse occupational hypersensitivity pneumonitis due to Cladosporium sp.