Cytotoxicity testing of carrier-based microcomposites for DPI application.

Inhalation is an attractive delivery route for systemic and local therapy. High local drug concentrations may permit non-invasive delivery, lower therapeutic doses, reduced systemic side-effects, and reduced metabolic degradation of the drug in the liver. In our earlier study, carrier-based microcomposites were prepared and investigated. The present study introduces studies of the cytotoxicity of meloxicam-containing microcomposites on monolayers of Calu-3 cells, in order to acquire information on its availability in pulmonary formulations. By relating cytotoxicity and drug dissolution, the appropriate amount of meloxicam for dry powder inhalation could be determined.

Biological and molecular characterisation of potential biocontrol strains of Trichoderma.

Thirty-four strains of seven species of Trichoderma isolated from various fungal sources were compared for direct mycoparasitic activity (MPA), chitinase production and antibiotic activity (ANA) in order to choose the most appropriate partners for a strain-breeding programme. Within species genetic differences were also assesses in T. hamatum, T. harzianum and T. viride by means of random amplification of polymorphic DNA (RAPD). Endochitinase activities of the Trichoderma strains ranged between 20.4 and 1264.5 units/g dry weight of mycelium. The correlation between MPA and chitinase activity was not unambiguous and no correlation existed between MPA and ANA. The RAPD patterns of T. viride strains were highly variable, while isolates of T. harzianum proved to be more uniform; T. hamatum revealed remarkable intraspecific divergence. All these three comprised certain pairs of strains that are promising participants of a strain-improving programme, since their strong genetic affinities offer good changes for combining their contrasted biocontrol traits.

Comparison of selected species of Bipolaris, Drechslera and Exserohilum by random amplification of polymorphic DNA.

Forty-six strains representing 15 species of Drechslera, five of Bipolaris and four of Exserohilum, as well as two formae of Drechslera teres were compared by RAPD analysis. Drechslera formed a large, heterologous group, while species of Bipolaris and Exserohilum were more closely related. Strong pair-wise affinities were observed between D. graminea and D. teres, D. tritici-repentis and D. bromi, D. siccans and D. biseptata, D. fugax and D. poae, B. sorghicola and B. zeicola, as well as between E. rostratum and E. turcicum.

Isoelectric focusing isozyme profiles and taxonomic distances among Fusarium species of the sections Arthrosporiella and Sporotrichiella.

Isozymes from 18 isolates representing seven species of the Fusarium sections Arthrosporiella and Sporotrichiella were compared by isoelectric focusing in polyacrylamide gels. Of the six enzyme systems tested esterase and malate dehydrogenase showed the largest variation. A numerical analysis of the pI values determined for acid phosphatase, esterase, glucose-6-phosphate dehydrogenase, malate dehydrogenase, phosphoglucose isomerase and phosphoglucomutase resulted in a dendrogam demonstrating the taxonomical relationships of the seven species. Fusarium avenaceum and Fusarium pallidoroseum were the two most closely related species. The high degree of isoenzyme dissimilarity among Fusarium chlamydosporum, Fusarium poae, Fusarium tricinctum, the fungi that produce pyriform or citriform microconidia, suggests that they are distinct species and their reduction to a variety level is not reasonable. The taxonomical distinctness of Fusarium camptoceras, a lesser known and rarely occurring fungus was also proven.