Insecticidal Activity of Ethyl Acetate Extracts from Culture Filtrates of Mangrove Fungal Endophytes

In the search for novel potent fungi-derived bioactive compounds for bioinsecticide applications, crude ethyl acetate culture filtrate extracts from 110 mangrove fungal endophytes were screened for their toxicity. Toxicity tests of all extracts against brine shrimp (Artemia salina) larvae were performed. The extracts with the highest toxicity were further examined for insecticidal activity against Spodoptera litura larvae and acetylcholinesterase (AChE) inhibition activity. The results showed that the extracts of five isolates exhibited the highest toxicity to brine shrimp at 50% lethal concentration (LC50) values of 7.45 to 10.24 ppm. These five fungal isolates that obtained from Rhizophora mucronata were identified based on sequence data analysis of the internal transcribed spacer region of rDNA as Aspergillus oryzae (strain BPPTCC 6036), Emericella nidulans (strains BPPTCC 6035 and BPPTCC 6038), A. tamarii (strain BPPTCC 6037), and A. versicolor (strain BPPTCC 6039). The mean percentage of S. litura larval mortality following topical application of the five extracts ranged from 16.7% to 43.3%. In the AChE inhibition assay, the inhibition rates of the five extracts ranged from 40.7% to 48.9%, while eserine (positive control) had an inhibition rate of 96.8%, at a concentration of 100 ppm. The extracts used were crude extracts, so their potential as sources of AChE inhibition compounds makes them likely candidates as neurotoxins. The high-performance liquid chromatography profiles of the five extracts differed, indicating variations in their chemical constituents. This study highlights the potential of culture filtrate ethyl acetate extracts of mangrove fungal endophytes as a source of new potential bioactive compounds for bioinsecticide applications.

Phosphate solubilizing ability of Emericella nidulans strain V1 isolated from vermicompost.

Phosphorus is one of the key factors that regulate soil fertility. Its deficiencies in soil are largely replenished by chemical fertilizers. The present study was aimed to isolate efficient phosphate solubilizing fungal strains from Eisenia fetida vermicompost. Out of total 30 fungal strains the most efficient phosphate solubilizing one was Emericella (Aspergillus) nidulans V1 (MTCC 11044), identified by custom sequencing of β-tubulin gene and BLAST analysis. This strain solubilized 13 to 36% phosphate from four different rock phosphates. After three days of incubation of isolated culture with black Mussorie phosphate rock, the highest percentage of phosphate solubilization was 35.5±1.01 with a pH drop of 4.2±0.09. Kinetics of solubilization and acid production showed a linear relationship until day five of incubation. Interestingly, from zero to tenth day of incubation, solubility of soil phosphate increased gradually from 4.31±1.57 to 13.65±1.82 (mg kg-1) recording a maximum of 21.23±0.54 on day 45 in respect of the V1 isolate. Further, enhanced phosphorus uptake by Phaseolus plants with significant pod yield due to soil inoculation of Emericella nidulans V1 (MTCC 11044), demonstrated its prospect as an effective biofertilizer for plant growth.

Molecular analysis and anticancer properties of two identified isolates, Fusarium solani and Emericella nidulans isolated from Wady El-Natron soil in Egypt against Caco-2 (ATCC) cell line

<p><b>OBJECTIVE</b>To characterize, identify and investigate the anticancer properties of two new soil fungal isolates, Emericella nidulans and Fusarium solani isolated from Wady El-Natron in Egypt against colon cancer Caco-2 (ATCC) cell line.</p><p><b>METHODS</b>Soil sample was cultured and two strains were chosen for morphological and phenotypical characterization. Partial sequences of the 18s rRNA gene and the internal transcribed spacer region ITS of the two isolates were amplified by PCR. Phylogenetic tree construction and analysis of the resulted multiple sequences from the two fugal isolates were also carried out. In vitro anticancer activity of the two strains was done against colon Caco-2 cancer cell line. Reverse transcription - PCR was carried out to detect level of expression of p53 in Caco-2 cell line.</p><p><b>RESULTS</b>HF.1 displayed morphological and genotypic characteristics most similar to that of Fusarium solani while HF.2 was most similar to Emericella nidulans with high similarity of 99% and 97% respectively. The multiple sequence alignment of the two fungal isolates showed that, the maximum identical conserved domains in the 18s rRNA genes were identified with the nucleotide regions of 51st to 399th base pairs, 88th to 525th base pairs respectively. While those in the ITS genes were identified with the nucleotide regions of 88th to 463rd and 51st to 274th. The two isolates showed IC50 value with (6.24±5.21) and (9.84±0.36) µg/mL) concentrations respectively at 28h. Reverse transcription - PCR indicated that these cells showed high level of expression for p53 mRNA.</p><p><b>CONCLUSIONS</b>The morphology and molecular analysis identified HF.1 and HF.2 to be Fusarium solani and Emericella nidulans; new isolates of anticancer producing fungi from Wady El-Natroon city in Egypt. Treatment with the two isolates caused P53 expression in Caco-2 cell line. These two isolates can be used as an anticancer agents.</p>

Molecular Genetics of Emericella nidulans Sexual Development

Many aspergilli that belongs to ascomycetes have sexuality. In a homothallic or self-fertile fungus, a number of fruiting bodies or cleistothecia are formed in a thallus grown from a single haploid conidia or ascospores. Genome-sequencing project revealed that two mating genes (MAT) encoding the regulatory proteins that are necessary for controlling partner recognition in heterothallic fungi were conserved in most aspergilli. The MAT gene products in some self-fertile species were not required for recognition of mating partner at pheromone-signaling stage but required at later stages of sexual development. Various environmental factors such as nutritional status, culture conditions and several stresses, influence the decision or progression of sexual reproduction. A large number of genes are expected to be involved in sexual development of Emericella nidulans (anamorph: Aspergillus nidulans), a genetic and biological model organism in aspergilli. The sexual development process can be grouped into several development stages, including the decision of sexual reproductive cycle, mating process, growth of fruiting body, karyogamy followed by meiosis, and sporulation process. Complicated regulatory networks, such as signal transduction pathways and gene expression controls, may work in each stage and stage-to-stage linkages. In this review, the components joining in the regulatory pathways of sexual development, although they constitute only a small part of the whole regulatory networks, are briefly mentioned. Some of them control sexual development positively and some do negatively. Regarding the difficulties for studying sexual differentiation compare to asexual one, recent progresses in molecular genetics of E. nidulans enlarge the boundaries of understanding sexual development in the non-fertile species as well as in fertile fungi.

Effect of Some Food Preservatives on the Lipolytic Activity of Beef Luncheon Fungi

Beef luncheon meat is one of the most popular meals in several countries in the world including Egypt. Thirty one fungal species and 3 species varieties were recovered from 30 samples of beef luncheon meat collected from different supermarkets in Qena. Alternaria, Aspergillus, Emericella, Mucor, Mycosphaerella, Penicillium and Rhizopus were the most common genera on the two types of media. From the above genera, the most prevalent species were Alternaria alternate, Aspergillus flavus, A. fumigatus, A. niger, A. terreus, Emericella nidulans, Mucor racemosus, Mycosphaerella tassiana, Penicillium chrysogenum and Rhizopus stolonifer. Screening of fungi for their abilities to produce lipase enzyme showed that, ten isolates represented 32.26% of total isolates appeared high lipase production, while sixteen isolates (51.61%) were moderate and 5 isolates (16.13%) were low producers. Aspergillus niger, Fusarium oxysporum and Nectria haematococca produced the highest amount of lipase enzyme, so these fungi were used in further studies. The incorporation of five food preservatives (Disodium phosphate, sodium benzoate, citric acid, potassium sorbate and sodium citrate) individually in the culture medium of lipase production exhibited an inhibitive effect on the mycelial growth and enzyme production by Aspergillus niger, Fusarium oxysporum and Nectria haematococca.

Reportes clínicos: infección probada por Aspergillus flavus y probable infección pulmonar por Emericella nidulans en pacientes inmunodeprimidos / Clinical reports: tested rhinosinusal infection by Aspergillus flavus and probable pulmonary infection by Emericella nidulans in immunodepressed patients

En los últimos 20 años la incidencia de aspergilosis invasiva ha aumentado entre 5 y 10 veces, presentando una mortalidad que varía desde un 60 a 98 por ciento dependiendo de su localización, enfermedad de base (inmunodepresión), diagnóstico y tratamiento precoz. A pesar que se ha logrado un importante avance en estos dos últimos decenios, aproximadamente un 50 por ciento de los casos se diagnostican post mortem. Se reportan dos casos de aspergilosis (probada y probable) en pacientes inmunodeprimidos de 21 y 44 años respectivamente. El primer caso corresponde a una infección rinosinusal en una paciente con leucemia linfoblástica, con un cuadro clínico caracterizado por aumento de volumen facial izquierdo, compromiso progresivo del estado general y equimosis en región periorbitaria. La endoscopia nasal detectó abundante secreción y tejido friable amarillento sugerente de infección micótica. Las muestras de tejidos enviadas al laboratorio para examen directo y cultivos arrojaron presencia de hifas en la mucosa y crecimiento abundante de Aspergillus flavus. Se inició terapia con itraconazol, cambiándose posteriormente a voriconazol, con respuesta favorable y disminución del dolor y volumen facial. Sin embargo, la paciente fallece al 10º día del ingreso debido a su mal estado general, avance de la falla medular y posterior insuficiencia respiratoria. El segundo caso corresponde a una probable infección pulmonar en una paciente con cáncer de mama en tratamiento quimioterápico. La paciente ingresó con el diagnóstico de neutropenia febril y probable neumonía de etiología bacteriana, fue tratada con antimicrobianos tanto en el hospital comunal como en el de base. Sin embargo, presentó una evolución tórpida, cursando posteriormente con hemoptisis, insuficiencia respiratoria y compromiso de conciencia. Se tomaron muestras de secreción endotraqueal las que fueron enviadas para estudio bacteriológico(TBC) y micológico, además de hemo y urocultivos. Los resultados de los...

In the lately twenty years the incidence of invasive spergillosis has increased five and ten times, causing a mortality rate ranging from 60 to 98 percent, depending on its location, nature of disease (immunodepression), diagnosis and forward treatment. In spite of the fact that there has been a significant progress in this lately period of twenty years, about 50 percent of cases were detected post mortem. Two cases of spergillosis (tested and probable) in 21 and 44 aged immunodepressed patients respectively are herein reported. The first case involves a rhinosinusal infection in a female patient diagnosed with lymphoblastic leukemia, whose clinical symptoms were an increase in the left volume of her face, a progressivecompromise in her overall state of health and ecchymosis in her periorbitary region. Nasal endoscopy revealed abundant secretion and yellowish friable tissues which suggested a mycotic infection. Samples of tissues sent to the lab for direct exam and cultures revealed the presenceof hypha in the mucus and an abundant growth of Aspergillus flavus. The first therapy was with itraconazol, changing later on to voriconazol what resulted in adecrease of pain and face volume. However, the patient dies on the tenth day of her ingress due to her bad state ofhealth, progress in glandular failure and ultimate respiratory insufficiency. The second case involves a probable pulmonary infection in a patient diagnosed with breast cancer and receiving chemotherapy treatment. She was ingressed with a febrile neutropenia and a probable bacterial etiology pneumonia and she was treated with antimicrobial medication both in the community hospital and in the base building. However, she showed a torpid evolution followed furthermore by hemoptisis, respiratory insufficiencyand consciousness compromise. Samples of endotraqueal secretion were taken in order to submit them to bacteriological and mycological (TBC) studies, together with hemo...

Occurrence of Fungal Species and Mycotoxins from Decayed Sugarcane (Saccharrum officinarum) in Egypt

Seventy-three fungal species belonging to forty-three genera were isolated from 40 samples of Saccharrum officinarum (collected from Naage-Hamadi canal in Qena Governorate, Egypt). Aspergillus, Trichoderma, Mucor and Pythium were the most common genera on the two isolation media. The dominant species of Aspergillus were A. niger, A. flavus, A. ustus, A. terreus and A. wentii. Some species were dominant on 40 g/l sucrose such as Aspergillus niger, A. flavus, Emericella nidulans, Trichoderma viride, Torula herbarum and Mamaria echinoeotryoides, while the dominant species on 10 g/l glucose were Mucor circinelloides, Aspergillus niger, Torula herbarum and Trichoderma viride. Mycotoxins including aflatoxins B1, B2, G1 and G2, zearalenone and diacetoxyscirpenol were detected in the examined samples of Saccharrum officinarum. The mycelial growth of A. flavus, A. niger, Fusarium moniliforme and Torula herbarum decreased with the increase in Dimethoate concentrations, although 25 ppm was less effective than the higher levels of the insecticide (75~200 ppm). Dimethoate stimulated the activity of Go-T in A. niger, F. moniliforme and T. harbarum, while the Go-T activity was inhibited in A. flavus with the Dimethoate treatments.

Mining microorganism EST databases in the quest for new proteins

Microorganisms with large genomes are commonly the subjects of single-round partial sequencing of cDNA, generating expressed sequence tags (ESTs). Usually there is a great distance between gene discovery by EST projects and submission of amino acid sequences to public databases. We analyzed the relationship between available ESTs and protein sequences and used the sequences available in the secondary database, clusters of orthologous groups (COG), to investigate ESTs from eight microorganisms of medical and/or economic relevance, selecting for candidate ESTs that may be further pursued for protein characterization. The organisms chosen were Paracoccidioides brasiliensis, Dictyostelium discoideum, Fusarium graminearum, Plasmodium yoelii, Magnaporthe grisea, Emericella nidulans, Chlamydomonas reinhardtii and Eimeria tenella, which have more than 10,000 ESTs available in dbEST. A total of 77,114 protein sequences from COG were used, corresponding to 3,201 distinct genes. At least 212 of these were capable of identifying candidate ESTs for further studies (E. tenella). This number was extended to over 700 candidate ESTs (C. reinhardtii, F. graminearum). Remarkably, even the organism that presents the highest number of ESTs corresponding to known proteins, P. yoelii, showed a considerable number of candidate ESTs for protein characterization (477). For some organisms, such as P. brasiliensis, M. grisea and F. graminearum, bioinformatics has allowed for automatic annotation of up to about 20 of the ESTs that did not correspond to proteins already characterized in the organism. In conclusion, 4093 ESTs from these eight organisms that are homologous to COG genes were selected as candidates for protein characterization