Pleurotus eryngii is considered a complex species owing to a perplexed structure within species and a wide geographical distribution. Due to its remarkable flavor, high nutritional value, and numerous medicinal features, P. eryngii is commercially cultivated on various raw plant materials. Its efficacy in using nutrients from lignocellulose residues is based on possession of a potent ligninolytic enzyme system, constituted of laccase, Mn-oxidizing peroxidases, and aryl-alcohol oxidase, which successfully degrade different aromatic compounds. Similarly, due to the ability of these enzymes, P. eryngii plays a very important role in many biotechnological processes, such as food production (edible basidiomata), biotransformation of raw plant materials to feed, biopulping and biobleaching of paper pulp, as well as bioremediation of soil and industrial waters.

The chemical composition and antimicrobial activities of essential oils isolated from Myrrhis odorata, Hypericum perforatum and Helichrysum arenarium were investigated against seven bacterial and six fungal species. Activity against the bacteria and C. albicans were investigated by a bioautographic test on TLC plates, while all the other fungi were tested by a microdilution test. The oil of H. arenarium showed the best antibacterial activity, while M. odorata oil showed the lowest effect, to compare with commercial products. In contrast, the best antifungal activity was observed for M. odorata oil, while H. arenarium showed the lowest antifungal potential. Minimal inhibitory and fungicidal concentrations for fungi were 0.5–120 μg/mL. The oil of M. odorata showed better activity then commercial product and it can be seen that this oil is very effective against all fungi tested.

Stereological and histochemical analyses of the glandular trichomes on leaves of Rosmarinus officinalis were carried out using light and fluorescence microscopy. Non-glandular and two types of glandular trichomes – peltate and capitate – are described. The stereological method was used for estimating the volume density of epidermis, mesophyll, mechanical tissue, central cylinder, intercellular spaces and volume density of different types of glandular trichomes. The results showed that the volume density of adaxial epidermis was higher than abaxial epidermis. The volume density of peltate trichomes was higher than the volume density of capitate ones. The values obtained for number of peltate and capitate trichomes showed that the capitate trichomes type I were more numerous. The histochemical tests showed positive reactions to proteins and polysaccharides for both types of trichomes, while the phenolic substances were found only in peltate trichomes