Diversidade da microbiota de fungos da própolis in natura / Diversity of in natura propolis fungal microbiota

O presente estudo teve por objetivo realizar a identificação dos fungos encontrados na própolis produzido por Apis mellifera L. da Baía do Iguape, Brasil. Para tanto, foram utilizadas técnicas morfológicas, bioquímicas e moleculares, sendo averiguado o perfil de restrição gerado por espaçador interno transcrito (ITS1 e ITS4). O tamanho dos produtos de PCR foi analisado quanto ao perfil de restrição obtidos com endonuclease (HhaI, HaeIII e HinfI) por espécie. Foram identificadas dezesseis espécies de fungos filamentosos: Flavodon flavus, Aspergillus nomius, Aspergillus versicolor, Cladosporium sp., Coniothyrium sidae, Didymella sp., Paecilomyces variotii, Cladosporium cladosporioides, Penicillium citrinum, Fusarium incarnatum, Penicillium chermesinum, Phoma sp., Stagonosporopsis valerianellae, Phoma medicaginis, Paraphoma fimeti e Stagonosporopsis cucurbitacearum; e seis espécies de leveduras: Candida tropicalis, Candida guiliermondii, Candida famata, Kodomala ohmeri, Trichosporon asahiu e Cryptococcus laurentii. Stagonosporopsis cucurbitacearum e leveduras pertencentes ao gênero Candida foram os microrganismos de maior ocorrência nas amostras da própolis provenientes da Baía do Iguape, Brasil.

Isolation and identification of microbiota from Egyptian common insect pests invading economically important crops

Insects bodies contain multiple distinctive microbial colonies which play key role in the metabolism, development and health of an insect. In the current study bacterial and fungal microbiota were isolated from larval feces and adult wings of two major insect pests in Egypt, the Cotton leaf worm Spodoptera littoralis and the black cutworm Agrotis ipsilon. Isolated pathogens were identified and characterized according to the scientific described methods in such cases. Two different genera of bacteria (Bacillus & Serratia) were isolated from larval feces of both insects while isolated fungus were Paecilomyces variotii and Absidia corymbifera from the feces of A. ipsilon larvae, while Rhozopus stolonifer and Penicillium chrysogenum were isolated from adults wings of the same insect. The fungus Aspergillus flavus, Aspergillus niger and Mucor circinilloides were isolated from feces of S. littoralis larvae. Numerous species of bacteria and fungi had been documented as a bio-agent against many insect pests, and most of them exhibited disruption in life-cycle of different species of Lepidopterous pests. The obtained data sheds light on microbial colonies associated with two major insect pests, however further studies are required to involve the isolated microbiota in the biological control programs of insect pests.

Identification, Documentation and Control of Biological Contamination in Middle Distillate Fuel

<p>The present study was initiated under a contract with the New Zealand Defence Scientific Establishment to document the nature, extent and possible sources of microbial contamination of middle distillate fuel ('Dieso' ) held in storage tanks at Devonport, Auckland, and to study possible methods for control of such contamination. Thirty-one fungal species and five bacteria were isolated during the period 1982-1984. The principal contaminants were the fungi Cladosporium resinae (the anamorph of Amorphotheca resinae Parbery), Penicillium corylophilum and Paecilomyces variotii. All three fungi produced dark mycelial mats at the water/diesel fuel interface in laboratory studies. Interactions between these fungi were observed. In the presence of Bushnell.-Haas mineral salts/diesel fuel phases Cladosporium resinae predominated while in seawater/diesel fuel phases Penicillium corylophilum predominated. All New Zealand and Australian isolates of C. resinae grew profusely in Bushnell-Haas mineral salts/diesel fuel phases. The biostatic/biocidal effects of chemicals on the predominant fungi in diesel fuel were studied in laboratory and field tests during 1984-1985. The most effective biocides in controlling C. resinae were benomyl, imazalil and Kathon 886. Imazalil had no effect on Paecilomyces variotii but when used in combination with benomyl a synergistic effect occurred at 100 ppm. Biobor JF, DEGME and EGME performed poorly in laboratory tests regardless of the amount of water present, but gave temporary inhibition of C. resinae in the field tests. Isolates from tanks treated with Biobor JF and DEGME grew well in the presence of these compounds in the laboratory. DML-7 and Proxel AS inhibited C. resinae and Penicillium spp. in both laboratory and field tests at a high dose of 300 ppm but were less effective against P. variotii. The effects of the biocides on engine performance and carbon deposits on engine components were studied. Recommendations for control of microbiological contamination of stored diesel fuel are given. In electron microscope studies no difference was observed in the intracellular structures between jet and diesel fuel isolates of C. resinae and the non-hydrocarbon utilizing Cladosporium cladosporioides.</p>

Identification, Documentation and Control of Biological Contamination in Middle Distillate Fuel

<p>The present study was initiated under a contract with the New Zealand Defence Scientific Establishment to document the nature, extent and possible sources of microbial contamination of middle distillate fuel ('Dieso' ) held in storage tanks at Devonport, Auckland, and to study possible methods for control of such contamination. Thirty-one fungal species and five bacteria were isolated during the period 1982-1984. The principal contaminants were the fungi Cladosporium resinae (the anamorph of Amorphotheca resinae Parbery), Penicillium corylophilum and Paecilomyces variotii. All three fungi produced dark mycelial mats at the water/diesel fuel interface in laboratory studies. Interactions between these fungi were observed. In the presence of Bushnell.-Haas mineral salts/diesel fuel phases Cladosporium resinae predominated while in seawater/diesel fuel phases Penicillium corylophilum predominated. All New Zealand and Australian isolates of C. resinae grew profusely in Bushnell-Haas mineral salts/diesel fuel phases. The biostatic/biocidal effects of chemicals on the predominant fungi in diesel fuel were studied in laboratory and field tests during 1984-1985. The most effective biocides in controlling C. resinae were benomyl, imazalil and Kathon 886. Imazalil had no effect on Paecilomyces variotii but when used in combination with benomyl a synergistic effect occurred at 100 ppm. Biobor JF, DEGME and EGME performed poorly in laboratory tests regardless of the amount of water present, but gave temporary inhibition of C. resinae in the field tests. Isolates from tanks treated with Biobor JF and DEGME grew well in the presence of these compounds in the laboratory. DML-7 and Proxel AS inhibited C. resinae and Penicillium spp. in both laboratory and field tests at a high dose of 300 ppm but were less effective against P. variotii. The effects of the biocides on engine performance and carbon deposits on engine components were studied. Recommendations for control of microbiological contamination of stored diesel fuel are given. In electron microscope studies no difference was observed in the intracellular structures between jet and diesel fuel isolates of C. resinae and the non-hydrocarbon utilizing Cladosporium cladosporioides.</p>

Fungal Resistance of Polymeric Composite Materials Based on Polypropylene and Natural Rubber

Research has been carried out to assess the impact of mold fungi on polymer composite materials based on polypropylene produced by Omsk Polypropylene Plant LLC and unrefined natural rubber produced in Vietnam, grade RSS-1. The amount of natural rubber varied up to 15% of the mass. The fungal resistance of the compositions to the following types of fungi was assessed: Aspergillus niger, Aspergillus terreus, Aspergillus flavus, Chaetomium globosum, Paecilomyces variotii, Penicillium funiculosum, Penicillium chrysogenum, Trichoderma viredens. The decrease in the weight of the samples after incubation depends on the content of natural rubber in the composition. With the content of natural rubber in the composition in an amount of 1%, the average weight loss is 0.4% by weight, and when the content of natural rubber is 15% by weight. already ~ 2% of the mass. Starting with the addition of natural rubber in an amount of 1% by weight, the growth of fungi occurs, and the degree of their development is characterized by points 3-5. The resulting compositions are biodegradable, susceptible to the action of fungi, and, therefore, the manufacture of materials based on them will be an environmentally friendly alternative for further use.

Paecilomyces variotii xylanase production, purification and characterization with antioxidant xylo-oligosaccharides production

Paecilomyces variotii xylanase was, produced in stirred tank bioreactor with yield of 760 U/mL and purified using 70% ammonium sulfate precipitation and ultra-filtration causing 3.29-fold purification with 34.47% activity recovery. The enzyme purity was analyzed on sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) confirming its monomeric nature as single band at 32 KDa. Zymography showed xylan hydrolysis activity at the same band. The purified enzyme had optimum activity at 60 °C and pH 5.0. The pH stability range was 5–9 and the temperature stability was up 70 °C. Fe2+and Fe3+ exhibited inhibition of xylanase enzyme while Cu2+, Ca2+, Mg2+ and Mn2+ stimulated its activity. Mercaptoethanol stimulated its activity; however, Na2-EDTA and SDS inhibited its activity. The purified xylanase could hydrolyze beechwood xylan but not carboxymethyl cellulose (CMC), avicel or soluble starch. Paecilomyces variotii xylanase Km and Vmax for beechwood were determined to be 3.33 mg/mL and 5555 U/mg, respectively. The produced xylanase enzyme applied on beech xylan resulted in different types of XOS. The antioxidant activity of xylo-oligosaccharides increased from 15.22 to 70.57% when the extract concentration was increased from 0.1 to 1.5 mg/mL. The enzyme characteristics and kinetic parameters indicated its high efficiency in the hydrolysis of xylan and its potential effectiveness in lignocellulosic hydrolysis and other industrial application. It also suggests the potential of xylanase enzyme for production of XOS from biomass which are useful in food and pharmaceutical industries.

Paecilomyces Pneumonia Despite Voriconazole Prophylaxis: A Case Report and Literature Review

Paecilomyces species are a rare cause of fungal pulmonary infections in immunocompromised hosts. Paecilomyces variotii and Paecilomyces lilacinus are the two most common species of clinical significance. Both species differ in their susceptibility to antifungal agents. We present a rare case of a 47-year-old immunocompromised woman who developed Paecilomyces pneumonia despite being on voriconazole prophylaxis. We also present a review of the literature on other reported cases.