Studies on Sensory and Phytochemical Characteristics of Poppy (Papaver somniferum L.) Varieties for Their Oil Utilisation.

Poppy is a significant pharmaceutical crop, but the seeds and the cold-pressed oil have a big potential as healthy foods. Breeding has mainly focused on agronomical characteristics and alkaloid content. Here, we compared the sensory values, fatty acid and headspace volatile composition of poppy oils and flours produced from different varieties. Two industrial and four culinary varieties were cultivated in our field in 2021-2022. The sensory test differentiated well among varieties. Typical poppy odour and flavour were stronger both in the oils and the flours of the blue-seed varieties compared to the white-seed ones. For most varieties, the harvest year caused no relevant differences. Linoleic, oleic, and palmitic acids were the main components both in oils and flours. Larger differences were detected in the volatiles (e.g., 2 and 3 methyl-butanal and 3 methyl-butanol γ-n-caprolactone, pentofuran), depending on genotype and year. A higher ratio of saturated fatty acids negatively influenced the flavour and odour characteristics. In the headspace volatiles, these features correlated negatively with 2-pentylfuran and hexanal. The oil content of poppy flour has a positive effect on colour, appearance, tactility and poppy flavour. Our results support a goal-oriented use of poppy genotypes for high-quality dietary products.

Inducing the Production of Secondary Metabolites by Foliar Application of Methyl Jasmonate in Peppermint.

Mentha x piperita is a major source of secondary metabolites (SMs), and developing tools to enhance these compounds would be beneficial to meet the increasing demand in the industry. Elicitation by plant hormones became a new strategy to reach this goal. Three experiments in a climatic chamber and two experiments in an open field were conducted with peppermint to explore the effect of methyl jasmonate (MeJa) on the essential oil (EO) content, EO composition, and the total phenolic content (TPC). The treatment was applied for all experiments by spraying the aerial parts of the plants with a dosage of 2 mM MeJa twice. The treatment influenced all the parameters studied in the trials. The volatile content increased by 9-35%; however, in one trial it remained unchanged. The treatment also affected the main compounds of the EO. Menthone increased significantly in two trials while pulegone and menthofuran decreased. In the case of menthol, the change may also be influenced by the phenological and developmental stages of the plants. In the majority of cases, the TPC was also elevated considerably due to the treatments. MeJa treatments may have promising effects in influencing the accumulation of biologically active compounds and the quality of the drug; therefore, further systematic studies are needed to optimize the technology in vivo.

Identification and quantification of essential oil content and composition, total polyphenols and antioxidant capacity of Perilla frutescens (L.) Britt.

The objective of this study was to investigate the volatile compounds of the leaves of ten perilla accessions as well as to determine total polyphenols, antioxidant capacity. Essential oil (EOs) content ranged from 0.33 to 1.75 mL/100 g d.w. in PS3 and J1 respectively. In this study sixty-five compounds were identified by GC-MS and characterized with the predominance of perillaldehyde, perilla ketone, ß-dehydro-elsholtzia ketone, limonene, shisofuran, farnesene (Z, E, α), ß-caryophyllene, trans-shisool. The biogenesis and composition of EOs are probably attributed to several factors. JTD3 had a significantly higher polyphenol content as well as showed the highest antioxidant capacity, whereas a strong positive linear correlation was observed between them. PS1 and NP 606 produced the maximum biomass correspondingly, while a large glandular trichome density was recorded for J1. The results support that perilla is rich in natural compounds that could be developed as nutraceuticals and/or phytomedicine.

The Influence of Cultivars and Phenological Phases on the Accumulation of Nevadensin and Salvigenin in Basil (Ocimum basilicum).

According to the earlier literature the optimum harvest time for basil is at the full flowering stage if accumulation of essential oil is taken into account. In this research we have investigated our gene-bank stored basil accessions to determine whether the harvest timing is variety specific or not considering their flavonoid accumulation pattern. In our work we have determined by HPLC the content of two main flavonoid compounds, salvigenin and nevadensin, of eight different gene bank accessions from 2013 of Ocimum basilicum L. Data were analysed with the nonparametric Kruskal-Wallis test. Multiple pairwise comparisons were made using the Conover-Iman procedure where the significance level was 5%. We have observed that the optimum harvest time is at the full flowering stage in the case of accessions 'Genovese' and 'Piros', but this was not verified for the others. The result of our experiment has shown that the maximum salvigenin and nevadensin content was detected both at the full- and early flowering period. Almost in all phenological phases the accession 'M. Grünes' accumulated the highest level of nevadensin, while accession 'Lengyel' produced the lowest results in all phenological phases. Generally it could be observed that compared with nevadensin more salvigenin is accumulated, and it is independent of the phenological phases. In the case of salvigenin, 'M. Grünes' accession produced the largest quantity and accession 'Dark Opal' showed the lowest values. Our analyses demonstrated that harvest at different phenological phases may result in different amounts of active agents according to the cultivar.