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.

Update of the Scientific Opinion on opium alkaloids in poppy seeds.

Poppy seeds are obtained from the opium poppy (Papaver somniferum L.). They are used as food and to produce edible oil. The opium poppy plant contains narcotic alkaloids such as morphine and codeine. Poppy seeds do not contain the opium alkaloids, but can become contaminated with alkaloids as a result of pest damage and during harvesting. The European Commission asked EFSA to provide an update of the Scientific Opinion on opium alkaloids in poppy seeds. The assessment is based on data on morphine, codeine, thebaine, oripavine, noscapine and papaverine in poppy seed samples. The CONTAM Panel confirms the acute reference dose (ARfD) of 10 µg morphine/kg body weight (bw) and concluded that the concentration of codeine in the poppy seed samples should be taken into account by converting codeine to morphine equivalents, using a factor of 0.2. The ARfD is therefore a group ARfD for morphine and codeine, expressed in morphine equivalents. Mean and high levels of dietary exposure to morphine equivalents from poppy seeds considered to have high levels of opium alkaloids (i.e. poppy seeds from varieties primarily grown for pharmaceutical use) exceed the ARfD in most age groups. For poppy seeds considered to have relatively low concentrations of opium alkaloids (i.e. primarily varieties for food use), some exceedance of the ARfD is also seen at high levels of dietary exposure in most surveys. For noscapine and papaverine, the available data do not allow making a hazard characterisation. However, comparison of the dietary exposure to the recommended therapeutical doses does not suggest a health concern for these alkaloids. For thebaine and oripavine, no risk characterisation was done due to insufficient data. However, for thebaine, limited evidence indicates a higher acute lethality than for morphine and the estimated exposure could present a health risk.