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This paper describes the microscopic details of conidial germination and the influence of pH, sodium chloride concentration, 3% glucose, 3% saccharose and ultraviolet irradiation on the conidial germination in Arthriniumspecies. Under laboratory conditions, germination started after an incubation period of 90 minutes in 2% malt extract broth at 25 °C. In vitro, the conidia of Arthriniumspecies have a very low percentage of germination (A. phaeospermum: 7.9%; A. aureum: 15.8%). Conidia of this genus have a characteristic equatorial slit. Conidia may break spontaneously at this slit, releasing their cytoplasmic contents. Arthrinium phaeospermumattains its optimum germination percentage when its conidia are suspended in a sterile saline solution (pH 3.5) in a water bath at 20 °C for 15 minutes before being inoculated on 2% malt extract agar. Conidial suspensions of A. aureummay be held in the same conditions, but for 30 minutes.

A low-cost thin-layer chromatographic method has been developed for the presumptive measurement of ochratoxin A (OTA) at 5 μg/kg in green coffee beans. The analytical method consisted of extracting OTA by shaking the beans with a mixture of methanol and aqueous sodium bicarbonate solution, which was then purified by liquid-liquid partition into toluene. OTA was separated by normal-phase two-dimensional thin-layer chromatography and detected by visual estimation of fluorescence intensity under a UV lamp at 365 nm. The chromatography solvents were toluene–methanol–formic acid (8:2:0.03) for the first development and petroleum ether–ethyl acetate–formic acid (8:10:1) for the second dimension development. This method was tested with uncontaminated green coffee bean samples spiked with an OTA standard at four different concentrations (5, 10, 20, and 30 μg/kg). The method is rapid, simple, and very easy to implement in coffee-producing countries. It is highly selective and does not involve the use of chlorinated solvents in the sample extraction step. This inexpensive method has been applied to different types of green coffee samples from various countries (Zimbabwe, Brazil, India, Uganda, Colombia, and Indonesia) and different manufacturers, and no OTA below the detection limit of 5 μg/kg was detected in any samples analyzed.

Abstract: Woronin bodies are cytoplasmic organelles of filamentous fungi that can be observed on one, or both sides of each septum. The goal of this paper is to illustrate the presence of them in hyphae of Arthrinium aureum by means of scanning electron microscopy and to show that they act as a safety plug to close septa pores in hypha. Results show that Woronin bodies as an immediate response to prevent a cytoplasm loss. Results support hypothesis proposed previously in literature.

Protoplast formation from conidia of Arthrinium aureumwas achieved with Lysing Enzyme L-2265 (Sigma Chemical®) from Trichoderma harzianum. Scanning electron microscopy of conidia protoplasts showed the acquired spherical shape.

Abstract: This paper is the first report in the literature of the presence of virus-like particles in the conidia and hypha of Arthrinium aureum. These particles, detected with an electron microscope, are spherical and 52 nm in diameter.

The Present work reports the study of the distribution of keratinophilic fungi isolated from 39 samples of soil collected in Brittany, France. Keratinophilic fungi were isolated from 35 (92.3%) of the samples studied. The most frequently found species wereFusarium moniliforme, Penicillium viridicatum and an unidentified species ofAcremonium. The other fungi isolated were members of the generaChrysosporium, Gliocladium, Mucor, Trichoderma andTrichophyton.