Consequences of Misnomer or Mistakes in Identification of Fungal Species.

The author, as a reviewer of many international journals, describes his long-standing experiences with incorrect identification of mushroom and fungal species and the resultant incorrect naming of those species that served as experimental models. From his own praxis, he selected several characteristic examples that sometimes ended in a curious situation. Some recommendations to authors of publications and persons responsible for the proper naming of mushrooms under study are summarized.

Collaborative study for the establishment of the third international standard for nystatin.

Due to the depletion in stocks of the World Health Organization (WHO) 2nd International Standard (IS) for nystatin, an international collaborative study was organised by the European Directorate for the Quality of Medicines & HealthCare (EDQM) to establish a replacement batch. Seventeen laboratories participated in the collaborative study, performing the microbiological diffusion assay to estimate the potency of the candidate 3rd International Standard for nystatin. The 2nd International Standard for nystatin was used as a standard to ensure the continuity of the unitage. Follow-up accelerated degradation studies demonstrated that the IS is stable when at the customary storage temperature of - 20 °C. The 3rd IS for nystatin was adopted by the WHO Expert Committee on Biological Standardization (ECBS) in 2006 with an assigned potency of 5710 International Units per mg (IU/mg). The 3rd IS for nystatin is available from the EDQM.

Antimicrobial activity of the methanolic extracts and compounds from Treculia obovoidea (Moraceae).

The crude extract from Treculia obovoidea was subjected to purification by repeated chromatography. Eight compounds were isolated from Treculia obovoidea and identified as Psoralen (1), Bergapten (2), 7-methoxycoumarin (3), 7-hydroxycoumarin (4), 4,2',4'-trihydroxychalcone (5), 4,2',4'-trihydroxy-3-prenylchalcone (6), 3-hydroxy-4-methoxybenzoic acid (7) and O-[3-(2,2-dimethyl-3-oxo-2H-furan-5-yl) butyl] bergaptol (8). These compounds together with the extract were tested for their antimicrobial activity against Gram-positive bacteria (six species), Gram-negative bacteria (12 species) and three Candida species using micro-dilution methods for the determination of the minimal inhibition concentration (MIC) and the minimal microbicidal concentration (MMC). The MIC values obtained with the crude extracts varied from 78.12 to 156.25 microg/ml against 17 (80.95%) of the 21 tested microorganisms. All the isolated compounds showed selective activity. The antimicrobial activity of this plant as well as that of compounds 6 and 8 is being reported for the first time. The obtained results provide promising baseline information for the potential use of these crude extract as well as some of the isolated compounds in the treatment of bacterial and fungal infections.

Screening chemical composition and in vitro antioxidant and antimicrobial activities of the essential oils from Origanum syriacum L. growing in Turkey.

In the present study, essential oil from the leaves of Syrian oreganum [Origanum syriacum L. (Lauraceae)] grown in Turkish state forests of the Dortyol district, Turkey, was obtained by steam distillation. The chemical composition of oil was analysed by GC and GC-MS, and was found to contain 49.02% monoterpenes, 36.60% oxygenated monoterpenes and 12.59% sesquiterpenes. The major components are as follows: gamma-terpinene, carvacrol, p-cymene and beta-caryophyllene. Subsequently, the reducing power, antioxidant and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activities of the essential oil were studied. The reducing power was compared with ascorbic acid, and the other activities were compared with 2,6-di-tert-butyl-4-methyl phenol (BHT, butylated hydroxytoluene). The results showed that the activities were concentration dependent. The antioxidant activities of the oil were slightly lower than those of ascorbic acid or BHT, so the oil can be considered an effective natural antioxidant. Antimicrobial activities of the essential oil from the leaves of Origanum syriacum was also determined on 16 microorganisms tested using the agar-disc diffusion method, and showed antimicrobial activity against 13 of these.

[Study of components of standard samples of polyene macrolide antibiotics by the methods of high performance liquid chromatography and SIEAP mass spectrometry]. / Izuchenie komponentnogo sostava standartnykh obraztsov polienovykh makrolidnykh antibiotikov metodom vysokoéffektivnoi zhidkostnoi khromatografii i mass-spektrometrii ERIAD.

The component composition of reference samples of polyenic macrolide antibiotics such as nystatin, mycoheptin, amphotericin B and levorin was studied by HPLC and chromatographic mass spectrometry in comparison to the WHO standards. It was shown that the samples were close by their component composition to the analogous samples of the WHO standards.

[Stabilization of standard samples of levorin and nystatin with antioxidants]. / Stabilizatsiia standartnykh obraztsov levorina i nistatina antioksidantami.

To prolong the storage period of the reference samples of levorin and nystatin, polyenic macrolide antibiotics, their effect of 23 antioxidants was studied by using rapid inactivation. The antioxidants belonged to compounds of different classes. The inactivation was performed at 20, 37 and 50 degrees C in the presence of 1, 2 or 5 per cent of the antioxidants. An antioxidant of the class of partially hydrated oxyquinolines was shown to have the highest stabilizing action on levorin and nystatin. It may be recommended for stabilizing the levorin and nystatin reference samples.