fungi

Heavy metals and metalloids are dangerous because they have the tendency to bioaccumulate in biological organisms over a period of time. However, it is conceived that a number of phytochemical agents as well microorganism can act as heavy metal removing agent both from human beings and the environment surrounding. For instance, microbes are used for the removal of heavy metals from the water bodies including bacteria, fungi, algae and yeast. This review shows that bacteria can play an important role in understanding the uptake and potential removal behaviour of heavy metal ions. The bacteria are chosen based on their resistance to heavy metals (incl. their toxicities) and capacity of adsorbing them. Due to specific resistance transfer factors, cell impermeability is drastically inhibited by several ion (i.e. mercury, cadmium, cobalt, copper, arsenic) forms. Between these elements, free-ion cadmium and copper concentrations in the biological medium provide more accurate determination of metal concentrations that affect the bacteria, than with most of the other existing media. Metal toxicity is usually assessed by using appropriate metal ion chelators and adjusting pH factor. Bacteria and metals in the ecosystem can form synergistic or antagonistic relationships, supplying each other with nutrients or energy sources, or producing toxins to reduce growth and competition for limiting nutritional elements. Thus, this relation may present a more sustainable approach for the restoration of contaminated sources.

A 64-year-old woman was referred to our hospital due to progressive dypnoea for the past week, combined with fever and type 1 respiratory failure. White blood cell count and procalcitonin level were normal. The Chest X-ray showed bilateral disseminated pulmonary infiltrates. Within the next 24 hours the patient developed a severe ARDS. A first diagnostic work-up for typical and atypical pathogens as well as serological tests for CMV, RSV, HIV and HSV were negative. Analysis of a second bronchoalveolar lavage fluid revealed Pneumocystis jiroveci DNA. The patient was successfully treated with trimethoprim-sulfamethoxazole and off label use with caspofungin. The cause of the infection was a six week treatment with dexamethasone. The patient developed a toxic epidermal necrolysis during further course, but completely recovered. Pneumonia with Pneumocystis jirovecii must also be taken into account in non-HIV patients, whenever there are any indications that cellular immunity may be depressed.

Fungi cause a variety of diseases and are difficult to treat owing to their eukaryotic nature resulting in dearth of antifungal targets at hand. This problem is further elevated many folds due to the resistance mechanisms of fungi through which they circumvent the antifungal drugs administered for therapeutic purposes. Fungi have a variety of strategies for obtaining these resistances, amongst them pivotal role is played by the ABC and MFS transporters. This article encompasses the important genes and their respective roles of both the classes of the transporters in different species of fungi.

Pulmonary mucormycosis is an uncommon pulmonary fungal disease, which is commonly seen in immunocompromised individuals. It is caused by fungi of class Zygomycetes. It constitutes the third most common invasive fungal infection following aspergillosis and candidiasis. Risk factors include patients with hematological malignancies, diabetes mellitus, and immunocompromised states. It is difficult to diagnose early due to non-specific clinical presentation and delay in treatment associated with greater mortality. As we know that Tuberculosis and HIV are highly prevalent in country like India. Post pulmonary tuberculosis is emerging as a risk factor for Pulmonary mucormycosis in the developing countries like India. Patients with non-resolving pneumonia are generally misdiagnosed as Pulmonary tuberculosis. The diagnosis of Pulmonary Mucormycosis is based upon demonstration of fungal hyphae in the clinical specimen. We highlight the importance of clinical suspicion in these cases for early diagnosis and early treatment initiation can reverse morbidity and mortality associated with Pulmonary Mucormycosis. We report 2 cases of Pulmonary mucormycosis present in post-pulmonary tuberculosis patients.

The process of hypothermia in the clinical setting has been practiced for 50 years and is known for its neuroprotective properties. This paper describes histopathological changes either by an ice sludge mimicking accidental hypothermia (S-group n=7) or by endovascular core-cooling (C-group n=7). Focal infiltrates of neutrophilic granulocytes were found in five of seven brains in the S-group and in one of seven brains in the C-group. These granulocytes were found in the arachnoids, in vessels, in vessel walls, and in the cerebral cortex. Fungi, bacteria, lymphocytes or plasma were not found. This experimental study, mimicking accidental hypothermia, reported histopathologic features of aseptic inflammation. To our knowledge, such findings have not been described in hypothermic animals or humans before. We suggest that a local inflammatory response may be triggered in such cases of hypothermia.

It is estimated that even up to 30% of buildings worldwide may be the subject of complaints connected with the quality of indoor air. Potential sources of air pollution can be both organic and inorganic particles. This article focuses on biological air pollutants from living and dead biological sources, especially those connected with fungi. Fungi found in the indoor air of domestic dwellings in a large extent are similar in their species composition to those found on the outside of the building. Microorganisms enters into the buildings during the airing of rooms or through the different slots and can develop on the surfaces of various materials. Intensively develops in a poorly ventilated, damp and dusty environments. For this reason the exposure to the indoor air pollution might be stranger for inhabitants than the expose to the impurities of the outdoor air. Presence of fungi in domestic dwellings can be very danger because of most often is associated with allergic reactions, mycotoxins, volatile organic compounds or even with fungal infections.

Aflatoxins, produced by Aspergillus spp., are strongly toxic and carcinogenic fungal secondary metabolites. Aflatoxin biosynthesis is a complex process and involves at least 30 genes clustered within an approximately 75 kB gene cluster. In this paper, we reviewed current status of the researches on the characterized structural genes involved in aflatoxin biosynthesis and their roles in aflatoxin-producing fungi, especially in A. flavus and A. parasiticus, which will improve our understanding of the mechanism of aflatoxin biosynthesis and regulation and provide reference for further study.

Pumpkins (Cucurbita pepo) are grown all around the world for a variety of reasons ranging from agricultural purposes to commercial and ornamental sales. The pathogens causing the rot of pumpkin in the world include fungi, bacteria, and viruses. The study was aim to identify fungal pathogens of pumpkin rot during storage, as well as control measures of the diseases using wood ash, mango leaf and rice chaff. Three hundred and sixty-six (366) fruits of pumpkins were studied in Pela, Gaya and Kulinyi districts of Hong Local Government Area of Adamawa State. The diseased samples (fruits) were randomly purchased. Of all the districts visited, Kulinyi has the highest percentage of disease samples (43.82%) while the least is Gaya district with 21.35%. Potato Dextrose Agar (PDA) was used for the isolation of pathogens and these gave Fusarium solani, Aspergillus niger, Aspergillus flavus, and Phytophthora capsici. All the fungal isolates exhibited different degree of pathogenic effect on the pumpkin fruits. The pathogens are susceptible to treatment both In-vitro and In-vivo control trials with wood ash and mango leaf at p ≤ 0.05. Inhibition improved with increased in concentration of the wood ash and mango leaf. Rice chaff treatment equally proved worthwhile with significant inhibition compared to the control at p ≤ 0.05.

Standardized method of seed treatment is of prime importance in the production of groundnut. The study was to carry out control trial using bark extract (aqueous and ethanol) and oil (seed) of mahogany (Khaya senegalensis) on seven (7) isolated fungi from two groundnut varieties (peruvian and valencia). The result shows that both mahogany bark and seed extracts are capable of inhibiting mycelial growth of all the isolates. There was no significant variation between the aqueous and ethanol bark extracts in-vitro, however the in-vivo test shows a significant difference between the aqueous and the ethanol bark extract in which the ethanol extract reduced growth of the pathogens more than the aqueous. For all the pathogens except Rhizopus stolonifer there was no growth between 50% to 100% concentration of the Khaya senegalensis oil in-vitro, however in-vivo control at 50% produced scanty to moderate growth for all the pathogens except Rhizopus stolonifer on peruvian, while there was full coverage on the seeds of valencia variety with Aspergillus niger and Rhizopus stolonifer having total coverage though Pseudaiiescheria boydii and Cylindrocarpon lichenicola were effectively inhibited and showed no growth at the 50% and 100%. Further research to focus on the quantifying the chemical constituents and formulation are suggested.

Clarireedia jacksonii sp. nov. Formerly Sclerotinia homoeocarpa F.T. Bennett, the causal agent of dollar spot (DS), is the most destructive pathogen in turfgrass. Symptoms appear as circular patches 10-40 mm in diameter with small tan lesions surrounded by a darker band, sometimes presenting an hour glass appearance. A multi-year study was initiated with the objective of determining the efficacy of biological control agents (BCA) and tank mixes of BCA’s and synthetic fungicides on DS control. Nutrient source was also evaluated to determine any interaction with the BCA’s and tank mixes. in vitro studies evaluated the efficacy of synthetic and BCA’s for C. jacksonii control. Quarter strength potato dextrose agar was amended with ¼, ½ and full labeled rates of various products. Chlorothalonil at all rates provided greatest (> 90%) control of C. jacksonii for study duration. Biological control agents provided best efficacy at ¼ and ½ label rates. Streptomyces griseoviridis provided least efficacy and may have exacerbated formation of C. jacksonii. Preventative field evaluations for synthetic and BCA’s provided different results between two study years. In Year 1, all treatments had < 15% disease severity for the duration of the study. In year 2, disease pressure was extremely elevated. Synthetic program 1, centered on azoxystrobin + propiconazole applications and conventional fertility sources, provided best results with < 5% disease severity for the duration of the study. Reduced synthetic program 1, and synthetic program 2 followed closely with < 10% disease severity. Reduced synthetic programs were based on monthly applications of either chlorothalonil or pyraclostrobin every 30 day, alternated with biofungicide applications. Synthetic program 2 utilized rotation applications of pyraclostrobin and chlorothalonil every 14 days. Organic programs, utilizing only biofungicides and organic fertility sources, provided the least amount of control and exceeded the 15% threshold by the second month of the evaluation period.

For many years, chemical pesticides have been performed to control different pests and diseases and this may be due to their broad spectrum of action, easy of application and the relatively low cost. But these chemicals have environmental risks, thus alternative control agents are needed. Chitosan is one of the novel suggested solutions to reduce the economic losses associated with chemical pesticides. Chitosan is naturally-occurring compound, as well as safe and biodegradable which obtained from certain natural sources. Chitosan have unique properties which help to control viruses, bacteria, fungi, insects, plant nematodes and other pests locally and systemically.

fusarium graminearum is one of the most popular phytopathogens of cereals worldwide. F. graminearum is the major causal agent of head blight of wheat and barley. Disease-resistant cultivar development, antagonistic microorganism usage and fungicide treatment are the most common strategies in head blight management strategies. However, these methods have some important disadvantages. The use of plant-derived essential oil against F. graminearum seems to be a promising approach due to the recent researches. This review summarizes the potential use of essential oils to fight against F. graminearum.

During the 2018 season, superficial dry and firm black spots, where sometimes an aerial mycelium developed, appeared on the rind of easy peeler mandarins causing high economic losses in fresh citrus exports from Perú. In this work, we have identified the causal agent, a species of Cladosporium not previously reported as a citrus pathogen. The pathogen was isolated from rind lesions of affected fruit and was identified by sequencing as Cladosporium ramotenellum; and fulfilment of Koch postulates was proven. This species was present on the surface of immature fruit in the groves, indicating that the infection is likely initiated before harvest. Cladosporium ramotenellum is resistant to the postharvest fungicides imazalil, pyrimethanil, and thiabendazole, but sensitive to propiconazole, prochloraz, and ortho-phenylphenol. We designed a postharvest industrial treatment to decrease the Cladosporium sp. load on the fruit surface that limited the incidence of infection and reduced the postharvest losses caused by the fungus. Although this species is quite ubiquitous, this is the first description of C. ramotenellum causing decay of citrus fruit, being the symptoms of this disease similar to the ones described previously and caused by Cladosporium cladosporoides in cv. Satsuma mandarins from Japan.

Strobilurin is a group of natural products and their synthetic analogs have been widely used to control and prevent fungal diseases. Strobilurins were firstly isolated in 1977 from the mycelium of Strobilurus tenacellus, a saprobic Basidiomycete fungus causing wood-rotting on forest trees. This group of pesticides was designed to manage fungal pathogens classes such as Ascomycetes, Basidiomycetes, and Oomycetes. Also, Strobilurin commercialized included derivatives such as are azoxystrobin, kresoxim-methyl, picoxystrobin, fluoxastrobin, oryzastrobin, dimoxystrobin, pyraclostrobin and trifloxystrobin. This group is a part of the larger group of QoI inhibitors, which act to inhibit the respiratory chain at the level of Complex III. Strobilurins group control an unusually wide array of fungal diseases, included water molds, downy mildews, powdery mildews, leaf spotting and rusts. This group are used on cereals, field crops, fruits, tree nuts, vegetables, turfgrasses and ornamentals. Also, Strobilurins found to enhance the plant growth in some cases.

The efficacy of chitosan and silicon oxide to prevent postharvest weight loss and fungi infection in 'Valencia Late' oranges was tested. Three silicon oxide concentrations (0.1%, 0.2%, 1%) were applied as preharvest treatments. Chitosan treatments were performed at the same concentrations in postharvest fruit. Preharvest applications were carried out by tractor spraying, while fruit were submerged for 30 seconds in baths with the chitosan concentrations in the postharvest applications. In both cases, a positive control (water treatment) and negative control (fungicide) were included. Treated fruit were stored in a chamber to simulate commercial storage conditions (4 ºC, 90% RH) for 9 weeks. After this time, the weight loss and damage caused by fungi due to natural infection were evaluated. Both silicon oxide and chitosan applications were effective in controlling natural infection by Penicillium species but had no positive effect on weight loss.

Pseudofungus structures in lymph node tissues have been reported on multiple occasions. Despite a variety of investigative tests including histochemical special stains and energy dispersive spectral analysis, the underlying nature and origin of these pseudofungus structures has never been clearly defined. The most common hypothesis suggests that they represent collagen fibers that become coated with iron and calcium. Herein, evidence is given that the pseudofungus structures identified in the lymph node tissues represent fragments of polyurethane catheters. The evidence includes both a comparison of these pseudofungus structures to fragments of polyurethane well documented in the literature and a comparison of polyurethane catheter scrapings to the pseudofungus structures identified in the literature. In both of these comparisons, the morphology of the polyurethane fragments are identical to the pseudofungus structures. This is the first definitive report identifying polyurethane catheter fragments as representing the true nature and etiology of pseudofungus structures in lymph node tissues.

Plant-parasitic nematodes (PPNs) are famous aggressive pests that attack several crops worldwide. A lot of farmers are suffering from nematode diseases which cause critical crop losses. At the same time, the most of available solutions for this problem are depending on synthetic nematicides. These chemical nematicides not only cause environmental and health problems but also may cause resistance in nematodes. Despite the occurrence of resistance in nematodes under field conditions still less clear. Therefore, this note is about the registered nematicides in Egypt which may help those who are interested in nematicides. Also, the chemical group and mode of action of nematicides were mentioned according to the insecticide resistance action committee (IRAC) [1] and fungicide resistance action committee (FRAC).

Invasive fungal infections are described as a continuous and severe harm to human health and they are associated with at least 1.5 million deaths worldwide each year. Amphotericin B exerts its activity through hydrophobic interactions with cell membrane ergosterol, cause the rupturing or leakage of cell membrane. The antifungal azole medicine group is classified as imidazoles (clotrimazole, ketoconazole, miconazole) and triazoles (fluconazole, itraconazole, voriconazole, posaconazole, isavuconazole) that are named according to the number of nitrogen atoms in the azole ring. Flucytosine is a first-line treatment for the management of cryptococcal meningitis. The most routine adverse effects of fluconazole involve accelerated liver enzymes, gastrointestinal complaints, headache, and skin rash. If antacids, PPIs, H2 blockers administered together with ketoconazole medicines; they will reduce the blood levels of ketoconazole by increasing gastric pH because ketoconazole requires an acidic media for dissolution and systematic absorption. Griseofulvin ruptures mitotic spindle during metaphase by interacting with fungal microtubules-(-), fungal mitosis (metaphase arrest), adequate to block expansion of fungi (drug is static), preventing them from damaging.

The post-harvest health and microbial safety of plant products and foods continue to be a global concern to farmers, consumers, regulatory agencies and food industries. A study was carried out to evaluate the pathogenicity of fungi associated with post-harvest rot of oranges, watermelons and bananas in Lafia, Nasarawa State, Nigeria. Healthy fruits inoculated with fungal spores obtained from rotted fruit tissues were incubated at ambient temperature conditions and observed daily for the appearance and development of tissue rot. Oranges and Watermelons had the highest number of fungal isolates (3) compared to banana (2). Fungi belonging to the genus Curvularia were the most isolated (37.50%), followed by both Aspergillus and Colletotrichum (25.00% respectively) and lastly Alternaria (12.50%). The highest tissue rot diameter of sweet orange (2.40 cm) was induced by Alternaria sp. followed by Curvularia geniculate (1.40 cm) and lastly Colletotrichum sp. (1.28 cm). The highest rot of banana fruit tissues was produced by A. niger (3.90 cm), followed by Curvularia geniculate (3.40 cm). Aspergillus sp. produced the highest tissue rot diameter on watermelon fruits (1.93 cm), followed by Colletotrichum sp. (1.30 cm) and lastly Curvularia geniculate (1.20 cm). Differences in the susceptibilities of different fruits to rot by fungal pathogens were significant (p ≤ 0.05). There is need for improved handling of fruits after harvest to prevent losses due to bacterial and fungal rots in the study area.

Indole acetic acid (AIA) is the most important plant growth hormone since it intervenes in the mechanisms of cell growth and differentiation and is produced mostly in the meristematic zones of the plant for apical dominance or root growth. AIA is also produced in root nodules and plant galls. In the latter cases, its presence is associated with endophytic bacteria. Although it is a plant growth hormone, it is also produced by bacteria such as Azospirillum brasilense and Bradyrhizobium japonicum. These species live in the soil (rhizosphere) or can colonize the roots (endophytic) of their hosts. From these bacteria, there are also isolates that are nitrogen fixers, which in addition to providing growth factors to plants, contribute by releasing nitrogenous molecules that improve plant nutrition.