Fungal infections of cultivated food crops result in extensive losses of crops at the global level, while resistance to antifungal agents continues to grow. Supercritical fluid extraction using CO2 (SFE-CO2) has gained attention as an environmentally well-accepted extraction method, as CO2 is a non-toxic, inert and available solvent, and the extracts obtained are, chemically, of greater or different complexities compared to those of conventional extracts. The SFE-CO2 extracts of Achillea millefolium, Calendula officinalis, Chamomilla recutita, Helichrysum arenarium, Humulus lupulus, Taraxacum officinale, Juniperus communis, Hypericum perforatum, Nepeta cataria, Crataegus sp. and Sambucus nigra were studied in terms of their compositions and antifungal activities against the wheat- and buckwheat-borne fungi Alternaria alternata, Epicoccum nigrum, Botrytis cinerea, Fusarium oxysporum and Fusarium poae. The C. recutita and H. arenarium extracts were the most efficacious, and these inhibited the growth of most of the fungi by 80% to 100%. Among the fungal species, B. cinerea was the most susceptible to the treatments with the SFE-CO2 extracts, while Fusarium spp. were the least. This study shows that some of these SFE-CO2 extracts have promising potential for use as antifungal agents for selected crop-borne fungi.

Silver fir (Abies alba Mill.) is one of the most common and valuable conifer tree species in Central Europe, with well-established usage in the construction and furniture industries, as well as the food, health products, pharmaceuticals and cosmetics industries. Silver fir branch extract, a mixture of antioxidative phenols, is produced industrially as a food supplement with a wide range of therapeutic properties. This study investigates optimization of the production of silver fir branch extract by researching its antioxidant activity (ABTS and DPPH assay), phenol content (Folin-Ciocalteu assay), lignan content (HPLC) and extractable content at various distances from the trunk (0–80 cm). The antioxidative activity, phenol content and extractable content decreased from the proximal to the distal part of the branch. The decrease in ABTS assay activity was 51%, and that of the DPPH assay was 52%; the decrease in total phenol content was 35–40%; and the decrease in lignan content was 91%. The extractable matter content was reduced by 40%. Data gained in the study herein justifies the importance of researching existing and industrially produced plant extracts for further optimization of the final product. Results shows that industry can also produce extracts with elevated content of lignans with the use of short proximal parts of the branches.

Norway spruce (Picea abies) is one of the most important commercial conifer species naturally distributed in Europe. In this paper, the composition and abundance of essential oil and hydrosol from the needles and branches of P. abies were investigated with an additional evaluation of changes related to different times of the year, annual shoots and branches, and differences in composition under different microenvironments. Essential oils and hydrosols obtained via hydrodistillation were analyzed using gas chromatography–mass spectrometry (GC-MS), where 246 compounds in essential oil and 53 in hydrosols were identified. The relative amounts of monoterpenes, sesquiterpenes, and diterpenes in essential oil changed significantly during the year, with the highest peak of monoterpenes observed in April (72%), the highest abundance of sesquiterpenes observed in August (21%), and the highest abundance of diterpenes observed in June (27%). The individual compound with the highest variation was manool, with variation from 1.5% (April) to 18.7% (June). Our results also indicate that the essential oil with the lowest allergenic potential (lowest quantity of limonene and linalool) was obtained in late spring or summer. Location had no significant influence on composition, while the method of collection for distillation (whole branch or annual shoots) had a minor influence on the composition. All nine main compounds identified in the hydrosol samples were oxygenated monoterpenes. The composition of P. abies hydrosol was also significantly affected by season. The method of preparing the branches for distillation did not affect the composition of P. abies hydrosol, while the location had a minor effect on composition.