Rhizopus Microsporus Research Articles

In Vitro Activity of Amphotericin B in Combination with Colistin against Fungi Responsible for Invasive Infections.

The in vitro interaction of amphotericin B in combination with colistin was evaluated against a total of 86 strains comprising of 47 Candida species (10 Candida albicans, 15 Candida auris, five Candida glabrata, three Candida kefyr, five Candida krusei, four Candida parapsilosis and five Candida tropicalis), 29 Aspergillus species (five Aspergillus flavus, 10 Aspergillus fumigatus, four Aspergillus nidulans, five Aspergillus niger, and five Aspergillus terreus), and 10 Rhizopus species (seven Rhizopus arrhizus, one Rhizopus delemar and two Rhizopus microsporus) strains. For the determination of the interaction, a microdilution checkerboard technique based on the European Committee on Antimicrobial Susceptibility Testing (EUCAST) reference method for antifungal susceptibility testing was used. Results of the checkerboard technique were evaluated by the fractional inhibitory concentration index (FICI) based on the Loewe additivity model for all isolates. Different inhibition endpoints were used to capture both the interaction at MIC and sub-MIC levels. Additionally, checkerboard technique results for Candida species were evaluated by response surface analysis based on the Bliss independence model. Against common Candida species, the combination was synergistic for 75% of the strains by FICI and for 66% of the strains by response surface analysis. For C. tropicalis, the interaction was antagonistic for three isolates by FICI, but antagonism was not confirmed by response surface analysis. Interestingly, synergistic and antagonistic FICIs were simultaneously present on checkboard microplates of all three strains. Against C. auris the combination was synergistic for 73% of the strains by response surface analysis and for 33% of the strains by FICI. This discrepancy could be related to the insensitivity of the FICI to detect weak interactions. Interaction for all other strains was indifferent. For Aspergillus and Rhizopus species combination exhibited only indifferent interactions against all tested strains.

Antifungal Activity of Calliandra Haematocephala against Selected Pathogenic Fungi: An In-vitro Study

Introduction: Pathogenic fungi cause a wide range of infections which include life-threatening diseases particularly in immunocompromised individuals. Plant derived secondary metabolites have significant therapeutic role in pathogenic fungal infection because of their fungicidal, immunity enhancing and least toxic properties. Calliandra haematocephala also called ‘Red Powder puff' possess greater antimicrobial and immunoadjuvant activities. Aim: To evaluate the antifungal activity of Calliandra haemato- cephala against selective pathogenic fungal species. Materials and Methods: The present in-vitro study was conducted in central laboratory in association with Department of Pharmacology at Sree Balaji Medical College, Chennai, Tamil Nadu, India, during six months from June 2018 to December 2018. Antifungal activity of the Calliandra haematocephala (leaves extract) were examined against six pathogenic fungal species Candida albicans, Aspergillus niger, Trichoderma viride, Rhizopus microsporus, Penicillium chrysogenum and Trichophyton rubrum using agar disc diffusion method by measuring the zone of inhibition. Results: The ethanolic leaf extract of Calliandra haematocephala showed strong inhibitory activity against all six fungal species. However, it showed significant inhibitory activity against Aspergillus niger (12 mm) and Penicillium chrysogenum (11 mm) when compared with standard drug Amphotericin B. Conclusion: The antifungal activity of Calliandra haematocephala suggested its potential role in opportunistic fungal infections with immunocompromised conditions.

Assessing the Fungal Simultaneous Removal Efficiency of Carbamazepine, Diclofenac and Ibuprofen in Aquatic Environment.

Unused pharmaceutical compounds (PhCs) discharged into the aquatic environment have been regarded as emerging pollutants due to potential harmful effects on humans and the environment. Microbial bioremediation is considered as a viable option for their removal from wastewater. The aim of this study was to assess the simultaneous removal of carbamazepine (CBZ), diclofenac (DCF) and ibuprofen (IBP) by previously isolated fungi (Aspergillus niger, Mucor circinelloides, Trichoderma longibrachiatum, Trametes polyzona, and Rhizopus microsporus). The tolerance to PhCs was conducted by tracking the fungal mycelium mat diameters in solid media and its dry biomass in liquid media, at the drug concentration range of 0.1 to 15 mg/L. The fungal enzymatic activities were determined for lignin peroxidase (LiP), manganese peroxidase (MnP) and laccase (Lac), respectively. The PhC removal efficiency of the fungi was assessed in aerated batch flasks and the drug concentrations and intermediate compounds formation were determined by using SPE-UPLC/MS. A tolerance over 70% was recorded for all the fungi at drug concentration of 0.1 mg/L. Manganese peroxidase was produced by all the fungi with very low amount of LiP, while all the enzymes were produced by T. polyzona. The pH of 4.3, temperature 37 ± 1.5°C and incubation time of 6 days were the optimum parameters for the fungal enzymatic activities. The best removal of CBZ (87%) was achieved by R. microsporus after 10 days. Between 78 and 100% removal of DCF was observed by all the fungi after 24 h, while 98% of IBP was removed after 2 days by M. circinelloides. Only a few intermediate compounds were identified after 3 days and disappeared after 10 days of incubation. This study demonstrated that apart from the basidiomycetes, the ascomycetes and zygomycetes are also producers of ligninolytic enzymes and have the ability to biodegrade emerging pollutants such as PhCs.

Stable and reproducible homologous recombination enables CRISPR-based engineering in the fungus Rhizopus microsporus

SummaryMucormycosis is a lethal and emerging disease that has lacked a genetic model fulfilling both high virulence and the possibility of performing stable and reproducible gene manipulation by homologous recombination (HR). Here, we developed a new methodology to successfully perform HR in Rhizopus microsporus. We isolated an uracil auxotrophic recipient strain and optimized the critical steps in the genetic transformation of this fungus. This was followed by an adaptation of a plasmid-free CRISPR-Cas9 system coupled with microhomology repair templates. We reproducibly generated stable mutants in the genes leuA and crgA, encoding a 3-isopropylmalate dehydratase and an ubiquitin ligase, respectively. Our new genetic model showed that mutations in the gene pyrF, a key virulence gene in several bacterial and fungal pathogens, correlated with an avirulent phenotype in an immunocompetent murine host. This was reverted by gene complementation, showing the broad possibilities of our methodology.

Successful treatment of pulmonary mucormycosis caused by Rhizopus microsporus with posaconazole

BackgroundMucormycosis is a rare fungal infection occurring chiefly in the lung or the rhino-orbital-cerebral compartment, particularly in patients with immunodeficiency or diabetes mellitus. Among Mucorales fungi, Rhizopus spp. are the most common cause of mucormycosis.Case presentationWe report a case of pulmonary mucormycosis caused by Rhizopus microsporus in a young patient with diabetes but no other apparent risk factors. The diagnosis mainly relied on clinical manifestation, positive pulmonary tissue biopsy, and fungal culture. The patient was successfully treated with posaconazole oral suspension and remains asymptomatic at one-year follow-up.ConclusionsPulmonary mucormycosis is a life-threatening condition and posaconazole is an effective treatment for pulmonary mucormycosis caused by Rhizopus microspores.

In Silico Designing of a Multitope Vaccine against Rhizopus microsporus with Potential Activity against Other Mucormycosis Causing Fungi.

During the current era of the COVID-19 pandemic, the dissemination of Mucorales has been reported globally, with elevated rates of infection in India, and because of the high rate of mortality and morbidity, designing an effective vaccine against mucormycosis is a major health priority, especially for immunocompromised patients. In the current study, we studied shared Mucorales proteins, which have been reported as virulence factors, and after analysis of several virulent proteins for their antigenicity and subcellular localization, we selected spore coat (CotH) and serine protease (SP) proteins as the targets of epitope mapping. The current study proposes a vaccine constructed based on top-ranking cytotoxic T lymphocyte (CTL), helper T lymphocyte (HTL), and B cell lymphocyte (BCL) epitopes from filtered proteins. In addition to the selected epitopes, β-defensins adjuvant and PADRE peptide were included in the constructed vaccine to improve the stimulated immune response. Computational tools were used to estimate the physicochemical and immunological features of the proposed vaccine and validate its binding with TLR-2, where the output data of these assessments potentiate the probability of the constructed vaccine to stimulate a specific immune response against mucormycosis. Here, we demonstrate the approach of potential vaccine construction and assessment through computational tools, and to the best of our knowledge, this is the first study of a proposed vaccine against mucormycosis based on the immunoinformatics approach.

A Case Series of Pulmonary Mucormycosis Caused by Rhizopus Microsporus

Mucormycosis is a relatively uncommon but intractable fungal infectious disease. The mortality is very high when it occurs. In this study, we reported a continuous cases of pulmonary mucormycosis in three patients who suffered from chronic kidney disease, history of renal transplantation and multiple myeloma in April 2017, respectively. Cultures were obtained from several specimens (pathological tissue, bronchoalveolar lavage fluid and sputum) and all identified as Rhizopus microsporus by Matrix-Assisted Laser Desorption Ionization Time- Of-Flight (MALDI-TOF) mass spectrometry and ITS DNA sequencing methods. In addition, they all showed susceptibility to amphotericin B and posaconazole. Unfortunately, even through the three patients all treated with amphotericin B and posaconazole, one man still died eventually. Clinicians should keep an eye on patients who are at high risk of acquiring this fatal disease and make early intervention strategies to reduce terrible outcomes.

Fungal Taxa Responsible for Mucormycosis/"Black Fungus" among COVID-19 Patients in India.

Mucormycosis is caused by fungi belonging to the order Mucorales. The term “Black Fungus” has been widely applied to human pathogenic Mucorales in India. They mainly infect the sinuses and brain, lungs, stomach and intestines, and skin. While this has been considered a rare disease, thousands of cases have been reported during the second wave of COVID-19 in India, between the months of April and June 2021. Hitherto, more than 45,374 cases and over 4300 deaths have been reported among COVID-19 patients across India from April 2021 to July 21, 2021. Though the mortality rate is estimated to be 50%, it could be above 90% if left untreated. In India, Rhizopus arrhizus has been related to be the most common species to cause human mucormycosis, followed by Apophysomyces variabilis, Rhizopus microsporus, and R. homothallicus. Accurate sample identification of human pathogenic Mucorales species is challenging especially due to the frequent lack of diagnostic morphological features. Traditionally, the culture-based approach has been extensively used to isolate and characterize human pathogenic Mucorales. However, this may not be an appropriate approach to objectively isolate and characterize all species, as the germination and growth of fungal spores are highly dependent on culture media and environmental conditions. Therefore, a robust approach to the accurate and rapid identification of human pathogenic Mucorales species is a prerequisite. The metagenomic approach comprehensively sequences and analyzes all genetic material in a complex biological sample and, consequently, this could be an appropriate approach to objectively characterize human pathogenic Mucorales taxa without the need for in vitro culture. The precise identification of the species will not only be useful for the correct diagnosis of this disease, but also for the development of antifungal drugs specific for each species. Accurate and rapid species identification is desperately needed to save lives in the mucormycosis outbreak among COVID-19 patients in India and neighboring countries.

Heterologous expression and biochemical characterization of a cold-active lipase from Rhizopus microsporus suitable for oleate synthesis and bread making.

Cold-active lipases which show high specific activity at low temperatures are attractive in industrial applications in terms of product stability and energy saving. We aimed to identify novel cold-active lipase suitable for oleates synthesis and bread making. A novel lipase gene (RmLipA) from Rhizopus microsporus was cloned and heterologously expressed in Pichia pastoris. The encoding sequence displayed 75% identity to the lipase from R. niveus. The highest extracellular lipase activity of 7931 U/mL was achieved in a 5-L fermentation. The recombinant enzyme (RmLipA) was optimally active at pH 8.0 and 20-25°C, respectively, and stable over a wide pH range of 2.0-11.0. The enzyme was a cold-active lipase, exhibiting > 80% of its maximal activity at 0°C. RmLipA was a sn-1,3 regioselective lipase, and preferred to hydrolyze pNP esters and triglycerides with relatively long chain fatty acids. RmLipA synthesized various oleates using oleic acid and different alcohols as substrates (> 95%). Moreover, it significantly improved the quality of bread by increasing its specific volume (21.7%) and decreasing its crumb firmness (28.6%). A novel cold-active lipase gene from R. microsporus was identified, and its application potentials were evaluated. RmLipA should be a potential candidate in oleates synthesis and bread making industries.

Isolation of Rhizopus microsporus and Lichtheimia corymbifera from tracheal aspirates of two immunocompetent critically ill patients with COVID-19

We describe two fatal cases of COVID-19 in which Rhizopus microsporus and Lichtheimia corymbifera were cultured from endotracheal aspirate samples. Both patients had no underlying comorbidities other than obesity. Despite antifungal therapy, both cases developed septic shock and progressive refractory hypoxemia without evidence of other underlying infections. It is unclear whether isolation of these fungal organisms represents invasive disease or corresponds to an epiphenomenon of critical illness. Yet, patients suffering from COVID-19 may be at risk of superinfection from a broader range of fungal organisms than previously thought.

Laboratory scale bioreactor studies on the production of l-asparaginase using Rhizopus microsporus IBBL-2 and Trichosporon asahii IBBLA1

Abstract l -asparaginase ( l -asparagine aminohydrolase, E.C. 3.5.1.1, ASNase) is an enzyme that is used primarily for the production of anti-neoplastic to treat Acute Lymphoblastic Leukemia (ALL). Current formulations of the enzyme are highly bacterial in nature which have resulted in adverse reactions. The current paper focusses on production of glutaminase and urease free ASNase in a laboratory scale bioreactor using two fungal species and their efficiency in the scaling up process. The isolated species are Rhizopus microsporus IBBL-2 and Trichosporon asahii IBBLA1 isolated from wheat bran and Antarctic moss respectively. The experiments were conducted under different conditions known as initial, optimized and immobilized. Enzyme activity at these conditions for Rhizopus microsporus IBBL-2 were found to be 10.85, 13.56, 17.18 U mL−1 respectively and for Trichosporon asahii IBBLA1 were found to be 13.97, 19.53, 21.98 U mL−1 respectively in laboratory scale. The consistency of the scale-up data from the shake flask level to the laboratory scale level was found to be greater than 90% efficiency. It was also observed that aeration condition had an impact on the enzyme production with maximum enzyme activity of 13.48 U mL−1 for the Rhizopus microsporus IBBL-2 and 19.95 U mL−1 for Trichosporon asahii IBBLA1 being reported at an aeration rate of 1 Lpm. The above results proved that laboratory scale production of ASNase has shown consistency and efficiency with respect to the flask-scale studies.

The viability of Rhizopus microsporus APBSMLF19 on different substrates and its application as a starter culture in tempeh fermentation

In addition to temperature and incubation time, inoculum is one of the key factors contributing to tempeh’s quality. At several regions in Java, usar, a traditional fungal inoculum obtained from teak leaves, is used for tempeh fermentation, however, there are some lacks in its application. Rice, cassava root and flour, as well as tapioca flour, were evaluated for their suitability as a substrate to support Rhizopus microsporus APBSMLF19 growth (fungi isolated from usar in Gunungkidul, Yogyakarta). About 100 ml/kg of 107 CFU/ml fungi suspension were inoculated to each substrate and incubated at 30 °C for 48 hours. After dried at 50 °C for ± 20 hours and mashed, the fungi viability was observed on weeks 0, 1, 2, and 4 during storage. The result showed no significant difference in the fungi’s number based on storage time for each starter culture’s type, but the inoculum exhibited different viabilities. However, there were no differences in texture measurements for all tempeh produced by using experimental and commercial starter culture (RAPRIMA®). Increasing the culture’s storage time for viability test is required in future research.

Microbial Community Succession and Metabolite Changes During Fermentation of BS Sufu, the Fermented Black Soybean Curd by Rhizopus microsporus, Rhizopus oryzae, and Actinomucor elegans

BS Sufu is a fermented food that is made by mixed black soybeans and soybeans. Microbial communities and metabolites play an important role for the final product. We characterized microbial diversity of BS Sufu during fermentation by high-throughput DNA sequencing. Meanwhile, volatile compounds were investigated by solid-phase microextraction (SPME) coupled with gas chromatography–mass spectrometry (GC-MS). The results showed that bacterial diversity was higher than that of fungi in BS Sufu. We found the existence of bacterial and fungal core communities, including Enterococcus, Enterobacter, Rhizopus, and Monascus. Network analysis indicated that bacterial and fungal communities maintain positive and negative interactions, which are important to shape the resident microbial communities in Sufu. In addition, 17 free amino acids (FAAs) were detected at the post-fermentation stage, and umami amino acid mainly contributed to taste of BS Sufu. Furtherly, a total of 79 volatile constituents in BS Sufu, including nine alcohols, 31 esters, and four aldehydes, form synergistically the unique odor of Sufu. Additionally, the correlations between microbiota and metabolites were analyzed. Our results suggested that these microbial taxa and metabolites contribute to the taste and flavor of BS Sufu. This study provided information for analysis of BS Sufu at different fermentation periods in terms of the microbial diversity and metabolites, and this information was important to understand the properties of mixed soybeans Sufu.

Diagnostics of Pulmonary Aspergillosis in Critically Ill Hematological and Non-Hematological Patients in the Intensive Care Unit By Combined Use of Galactomannan, 1-3-Beta-D-Glucan, Aspergillus Specific PCR and Conventional Culture in Concurrent Blood and Bronchoalveolar Lavage Samples — Results of a Multicenter Prospective Pilot Study

Invasive pulmonary aspergillosis (IPA) is a life-threatening infectious complication mainly affecting immunocompromised hematological patients. Therapeutic success requires early and precise diagnostics. Few data are available on the performance of current diagnostic tests in patients admitted to the intensive care unit (ICU) as the majority of diagnostic studies is conducted in hematological patients and results cannot readily be transferred to patients in the ICU setting.In a prospective multicenter study, we evaluated concurrent bronchoalveolar lavage (BAL) samples and concurrent blood samples from 44 patients admitted to the ICU who required mechanical ventilation and therefore underwent a diagnostic work-up including chest CT scan and BAL (NCT01695499). The subsequent diagnostic work-up comprised of conventional methods for direct detection of Aspergillus spp. as well as biomarkers such as galactomannan (GM) and 1-3-beta-D-glucan (BDG) and an Aspergillus specific nested polymerase chain reaction (PCR).14 patients (32%) suffered from a hematological/hematooncological disease, of which 7 had received allogeneic stem cell transplantation. 6 patients (14%) had a solid tumor requiring chemotherapy. The remaining 24 patients (54%) had no hematological or oncological disease. 11 patients were neutropenic with ANC <1.0/nl (10 belonged to the hematooncological group). According to AspICU classification (Blot et al., Am J Respir Crit Care Med 2012) 9 patients (20%) had putative IPA (3 patients with hematological malignancy). Other invasive fungal diseases (IFD) besides IPA were observed: positive growth of Rhizopus microsporus in BAL was seen in one patient. Furthermore, two cases of disseminated candidiasis with positive growth in blood culture (C.albicans, C.krusei) and one case with positive growth in ascites (C.albicans). Additionally, two cases of Pneumocystis jirovecii pneumonia (PcP) were diagnosed.Diagnostic performance of each single test and of test combinations was analyzed. GM and PCR showed superior performance in BAL (sensitivity/specificity of 56%/94% (GM) and 44%/94% (PCR) compared to 33%/97% and 11%/94% in serum). Despite a better sensitivity of 89%, BDG showed a specificity of only 31% in BAL and 26% in serum, reducing the diagnostic odds ratio (DOR) to 3.7 and 2.8, respectively. For hematological patients the mean GM optical density index (ODI) in BAL was 0.97 and in serum 0.58 compared to 0.59 and 0.16 in non-hematological patients. The strength of agreement between GM in BAL and GM in serum as calculated by Cohen's kappa intertest coherence analysis was 0.62 [0.29-0.95], which is considered to be good. BDG levels and performance of the PCR assay did not differ between hematological and non-hematological patients. The combined use of biomarkers in BAL showed a diagnostic performance of sensitivity/specificity/PPV/NPV and DOR of 89%/31%/25%/92% and 3.67. Testing of GM and BDG solely in serum resulted in a combined test performance of 89%/26%/ 24%/ 90% and 2.77. GM (BAL) combined with BDG (serum) showed high joint sensitivity of 100% with specificity of 25% (DOR 6.81). Using PCR instead of GM dropped sensitivity to 89% (specificity 23%, DOR 2.37). Diagnostic performance of combined GM and PCR testing in BAL showed sensitivity/specificity/PPV/NPV and DOR 67%/89%/60%/91% and 15.0. Cohen's kappa for PCR (BAL) vs. GM (BAL) was 0.49 [0.145 to 0.840], which is considered to be moderate. If a diagnostic algorithm defines BDG (serum) as an initial test that is, in case of a positive result, followed by a confirming test combination from BAL with strong or even exclusive specificity for Aspergillus spp. (GM, PCR and culture) a diagnostic performance is achieved with sensitivity/specificity/positive predictive value/negative predictive value of 88%/97%/88%/97% and DOR >100.This study intended as a pilot study underscores the concept of combined testing in serum and BAL for optimized detection of IPA and provides valuable data for the emerging cohort of critically ill patients, both hematological and non-hematological. Further studies with hematological ICU patients in larger cohorts are planned. DisclosuresBoch:Pfizer research grant (WS 2274964): Research Funding. Buchheidt:Pfizer research grant (WS 2274964): Research Funding.

Antifungal Activity of Iron-gold and Cobalt-gold co-doped ZnO Nanoparticles

Zn0.98Fe0.01Au0.01O and Zn0.98Co0.01Au0.01O nanoparticles (NPs) have been synthesized via poly ethylene glycol assisted route. The average crystallite size of Zn0.98Fe0.01Au0.01O and Zn0.98Co0.01Au0.01O NPs were estimated from X-ray diffraction results and the values are 31.38 nm and 36.14 nm respectively. The UV absorption spectra confirmed the formation of the NPs with the characteristic peaks at 374 and 366 nm respectively. This spectral observation indicates that the band gap of ZnO nanoparticles decreases by doping iron/gold and cobalt/gold nanoparticles. The morphology and elemental composition of Zn0.98Fe0.01Au0.01O and Zn0.98Co0.01Au0.01O NPs were investigated. The antifungal activity of synthesized Zn0.98Fe0.01Au0.01O and Zn0.98Co0.01Au0.01O NPs were found against four postharvest pathogenic fungi like Aspergillus niger, Aspergillus flavus, Rhizopus microsporus and Pencillium sp. The doping of iron and gold in ZnO nanoparticles enhances the zone of inhibition for the fungal pathogens compared to pure ZnO nanoparticles. Antifungal activity of Zn0.98Fe0.01Au0.01O and Zn0.98Co0.01Au0.01O nanoparticles were higher when compared with standard antibiotic mycostatin whose zone of inhibition is 18 mm against Aspergillus niger, Aspergillus flavus, Rhizopus microsporus and Pencillium sp.

Gastric Mucormycosis by Rhizopus microsporus in a Patient with Uncontrolled Diabetes Mellitus

Gastric Mucormycosis by Rhizopus microsporus in a Patient with Uncontrolled Diabetes Mellitus

Epidemiology of Mucormycosis in India.

Mucormycosis is an angioinvasive disease caused by saprophytic fungi of the order Mucorales. The exact incidence of mucormycosis in India is unknown due to the lack of population-based studies. The estimated prevalence of mucormycosis is around 70 times higher in India than that in global data. Diabetes mellitus is the most common risk factor, followed by haematological malignancy and solid-organ transplant. Patients with postpulmonary tuberculosis and chronic kidney disease are at additional risk of developing mucormycosis in this country. Trauma is a risk factor for cutaneous mucormycosis. Isolated renal mucormycosis in an immunocompetent host is a unique entity in India. Though Rhizopus arrhizus is the most common etiological agent of mucormycosis in this country, infections due to Rhizopus microsporus, Rhizopus homothallicus, and Apophysomyces variabilis are rising. Occasionally, Saksenaea erythrospora, Mucor irregularis, and Thamnostylum lucknowense are isolated. Though awareness of the disease has increased among treating physicians, disease-associated morbidity and mortality are still high, as patients seek medical attention late in the disease process and given the low affordability for therapy. In conclusion, the rise in the number of cases, the emergence of new risk factors and causative agents, and the challenges in managing the disease are important concerns with mucormycosis in India.

Isolation and Characterization of Fungi strains associated with Mycotoxin Production from Bambara (Vigna subterranea (L) verdc) nuts Recovered in Nigeria

Fungal contamination of food commodities is a global food security challenge that impacts negatively on the health of consumers. Mycotoxins are produced as secondary metabolites by some pathogenic fungi and may contaminate agricultural products while on the field or during harvesting and storage. A field survey was conducted in order to isolate and identify the mycotoxin-producing fungal strains in Bambara nut collected from major markets in eight States in Nigeria including Oyo, Ogun, Lagos, Ekiti, Kwara, Kogi, Abuja, and Nasarawa. Samples per site were pooled, processed and screened for the presence of mycotoxin-producing fungi by culture technique and intergenic spacer sequencing (ITS). Mycotoxin production was determined using thin layer chromatography (TLC) with scanning densitometer. Twenty-four mycotoxin-producing fungal species were isolated from Bambara samples, which were identified as Talaromyces pinophilus, Macrophomina phaseolina (6), Fusarium oxysporum (2), Aspergillus foetidus, Aspergillus flavipes, Rhizopus oryzae (2), Phanerochaete chrysosporium, Aspergillus flavus (2), Aspergillus terreus, Aspergillus awamori, Aspergillus welwitschiae, Rhizopus microsporus, Ceriporia lacerate and Fusarium verticillioides (accession numbers of MN42329- MN4233323) from Bambara nuts. The genera Macrophomina were the most dominant. Some of the identified fungi are noted for the production of mycotoxins and mycotoxins exert toxic effects on animals and humans. The fungi associated with Bambara nut diseases were identified and can be taken as targets in varietal improvement of Bambara nut for resistance to fungal diseases in Nigeria.

Thermophilic fungi in Araucaria Forest, Atlantic Forest Biome, Brazil.

Thermophilic fungi constitute an ecologically well-defined group, commonly found in environments wherever decomposition of organic matter takes place, making them self-heating. The importance of thermophilic fungus in ecosystems contrasts with the incompleteness of our understanding of the group's biogeography patterns, phylogenies and coevolution relationships. Actually, the lack of data about thermophilic fungi from the Brazil is a limiting factor that also contributes for this scenario. In order to reduce this gap of knowledge, we aimed to characterize thermophilic filamentous fungi in Araucaria Forest, Atlantic Forest biome. Species identification was achieved by using internal transcribed spacers (ITS) as molecular ribosomal markers. In total, 240 heat-tolerant fungal strains were isolated and identified as Thermothielavioides terrestris, Thielavia sp., Thermoascus crustaceus, Aspergillus fumigatus, Rhizomucor miehei, Rhizomucor pusillus, and Rhizopus microsporus. All thermophilic strains exhibited optimal growth at 45 °C. T. crustaceus, T. miehei e R. pusillus were the dominant species, with the frequencies of occurrence of 35.00%, 28.33% and 23.33%, respectively. Our data reveals the apparent diversity of the Neotropical realm and may serve as reference to future studies that will try to elucidate important aspects of group.

Utility of 2-Deoxy-2-[18F]fluoro-Dglucose positron emission tomography/computed tomography scan in the systemic evaluation of patients with post-COVID-19 endogenous presumed fungal endophthalmitis.

A 48-year-old nondiabetic male presented with persistent breathlessness, cough, intermittent pyrexia, and grossly reduced vision in the right eye. Based on the available records, he had been diagnosed with COVID-19 earlier (based on a positive RT-PCR) and had received domiciliary care for an initial five days. Following clinical deterioration, he was admitted, treated with systemic steroids, antibiotics, and ventilatory support. Ten days post discharge, he developed a gross reduction in vision in the right eye (CF: 1 m). Five days later, he underwent a vitrectomy for endophthalmitis with intravitreal voriconazole (100 mcg), vancomycin (1 mg), and ceftazidime (2.25 mg) with a reported postoperative vision of 6/24 (20/80). Microbiology of the vitreous fluid for KOH, gram staining, and culture/sensitivity were reported as negative. He was readmitted in our tertiary care center on the 14th day postoperatively. On admission, he was afebrile, with tachycardia (heart rate: 91/min), dyspneic (respiratory rate: 21/minute) with inspiratory basilar crackles with decreased air entry bilaterally. His oxygen saturation was normal (99%). The visual acuity was HMCF in the right eye and 6/6 (20/20) in the left eye. Dilated fundus exam showed significant vitreous haze (3+) that obscured the fundus view [Fig. 1]. A large yellowish preretinal lesion was seen in the superonasal quadrant [Fig. 2]. The fundus of the left eye was normal.Figure 1: Fundus photo of the right eye revealing vitreous haze grade 3+Figure 2: Fundus photo revealing a yellow-white preretinal lesion in the superonasal quadrantBlood investigations included assessment of the hemoglobin (11.30 gm/dl), white cell counts (11,170/mm3), and serum creatinine (1.05 mg/dl), which were normal. Specific tests included C-reactive protein (45.56 mg/l), D-dimer (2910 ng/ml), and serum fibrinogen (590 mg/dl). Blood cultures for aerobic, anaerobic, and fungal cultures were negative. He underwent a whole-body 2-Deoxy-2-[18F]fluoro-D-glucose (FDG) Positron Emission Tomography/Computed Tomography (PET/CT) scan to detect a possible focus of infection. A high-grade uptake was seen in an area of patchy consolidation, and additional moderate grade uptake was seen in large cavitary lesions in each lung [Fig. 3]. Multiple nodular opacities through the rest of the lung fields demonstrated low-grade uptake. A CT-guided biopsy at an area of high uptake (right lung; lower lobe) was performed [Fig. 4]. Histopathological study showed extensive areas of necrosis enmeshed with broad aseptate hyphae. Scattered granulomas were also seen. The picture was consistent with invasive fungal infection. Fungal cultures of the lung biopsy revealed Rhizopus species. The isolates were analyzed by MALDI TOF MS (Matrix-assisted laser desorption ionization-time of flight-mass spectroscopy) to confirm a species identification of Rhizopus microsporus. The patient underwent two intravitreal amphotericin B injections (5 mcg, a week apart) along with an intravenous amphotericin B course (3 mg/kg/day) for six weeks, with no clinical improvement (perception of light only). Subsequent ultrasound examination revealed a large multilobular intraocular mass attached to the posterior pole with a thickened membrane in the mid-vitreous [Fig. 5]. The patient opted to be treated elsewhere and was discharged.Figure 3: (a-c) High-grade uptake (white arrowhead; SUV max 11.45) seen in patchy consolidation within the posterior aspect of the right lung lower lobe. Moderate grade uptake seen in large cavitary lesions in the right lung middle and lower lobes (red arrows; SUV max 7.8). (b-d) CT scans revealing multiple cavitary lesions of the right lung (red arrows)Figure 4: CT scan showing biopsy needle placement within the cavitary lesion (white arrowhead)Figure 5: Ultrasound image of the eye showing a large multilobular mass attached to the posterior pole and to a thickened mid-vitreal membranePost-COVID-19 endogenous endophthalmitis is increasingly being recognized, and identification of the systemic focus and its treatment is an integral part of treatment.[1] Fungal endophthalmitis due to mucor species has only rarely been reported.[2] The use of a FDG PET/CT scan allowed identification of a pulmonary focus and suggested potential sites of biopsy, thus increasing the possibility of a positive diagnosis. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.