The toxicity risks, instability of essential oil, and complex composition are principal obstacles to using essential plant oil for clinical applications. Solving stability-related problems, providing targeted drug delivery, and decreasing plant essential oil toxicity, encapsulation can be used successfully. Rosemary (Rosmarinus officinalis) is a perennial plant of the Lamiaceae family with various healing properties. However, the rosemary essential oil, as volatile oil, is fast evaporated, which limits its applications. This study’s goal is to boost the prevent evaporation and bioactivity of rosemary essential oil by developing zein-NPs as a promising NDS (nano-drug-delivery system) and assessing the effect of NPs on the rosemary essential oil efficacy. Scanning electron microscopy (SEM) showed NPs sizes between 70–200 nm. With dynamic light scattering analysis (DLS), the average size of zein nanoparticle-containing rosemary essential oil (NPZLA) was obtained at ca. 154.5 nm. The entrapment efficiency (EE) on rosemary essential oil was ca. 71% inside the zein NPs. The in vitro release suggests that the polymeric barrier can control the rosemary essential oil release. Zein-NPs can be potentially used as NC (nanocarrier) for enhancing the evaporation inhibitor of ether oil of rosemary essential oil to enhance its bioavailability and performance further. It can be concluded that rosemary plant can be used as the core inside the nanoparticle by biological production method due to its medicinal properties and other properties. Based on the stated content, it is clear that in the future, by conducting more extensive research, the necessary platform can be provided for the use of this medicinal plant as much as possible in the pharmaceutical industry.

The use of growth-stimulating signals to increase the tolerance of plants to water deficits can be an important strategy in the production of plants in dry areas. Therefore, a split-plot experiment with three replications was conducted to evaluate the effects of sodium nitroprusside (SNP) application rate as an NO donor (0, 100, and 200 µM) on the growth and yield parameters of Silybum marianum L. (S. marianum) under different irrigation cut-off times (control, irrigation cut-off from stem elongation, and anthesis). The results of this study showed that with increasing drought severity, leaf RWC, proline content and capitula per plant, 1000 grain weight, plant height, branch per plant, capitula diameter, and the biological and grain yield of S. marianum decreased significantly, whereas the number of grains per capitula increased compared with the control. Also, by irrigation cut-off from the stem elongation stage, the density of leaf stomata at the bottom and top epidermis increased by 64% and 39%, respectively, and the length of the stomata at the bottom epidermis of the leaf decreased up to 28%. In contrast, the results of this experiment showed that the exogenous application of nitric oxide reduced the negative effects of irrigation cut-off, such that the application of 100 µM SNP enhanced RWC content (up to 9%), proline concentration (up to 40%), and grain (up to 34%) and biological (up to 44%) yields in plants under drought stress compared with non-application of SNP. The decrease in the number of capitula per plant and capitula diameter was also compensated by foliar application of 100 µM SNP under stress conditions. In addition, exogenous NO changed the behavior of the stomata during the period of dehydration, such that plants treated with SNP showed a decrease in the stomatal density of the leaf and an increase in the length of the stomata at the leaf bottom epidermis. These results indicate that SNP treatment, especially at 100 µM, was helpful in alleviating the deleterious effects of water deficiency and enhancing the tolerance of S. marianum to withholding irrigation times.

In this study, phytochemicals extracted from three different Achillea genera were identified and analyzed to be screened for their interactions with the SARS-CoV-2 main protease. In particular, the antiviral potential of these natural products against the SARS-CoV-2 main protease was investigated, as was their effectiveness against the SARS-CoV-1 main protease as a standard (due to its high similarity with SARS-CoV-2). These enzymes play key roles in the proliferation of viral strains in the human cytological domain. GC-MS analysis was used to identify the essential oils of the Achillea species. Chemi-informatics tools, such as AutoDock 4.2.6, SwissADME, ProTox-II, and LigPlot, were used to investigate the action of the pharmacoactive compounds against the main proteases of SARS-CoV-1 and SARS-CoV-2. Based on the binding energies of kessanyl acetate, chavibetol (m-eugenol), farnesol, and 7-epi-β-eudesmol were localized at the active site of the coronaviruses. Furthermore, these molecules, through hydrogen bonding with the amino acid residues of the active sites of viral proteins, were found to block the progression of SARS-CoV-2. Screening and computer analysis provided us with the opportunity to consider these molecules for further preclinical studies. Furthermore, considering their low toxicity, the data may pave the way for new in vitro and in vivo research on these natural inhibitors of the main SARS-CoV-2 protease.

Capparis spinosa L. (caper) is an important medicinal plant whose bioactive compounds vary significantly depending on its growth stage. This directly affects its pharmaceutical and nutritional value. Collecting C. spinosa at the optimal growth stage is essential to achieving high phytochemical quality and meeting consumer needs. This study aimed to evaluate the variation of these active compounds in the aerial parts of C. spinosa across four phenological stages (vegetative, flowering, unripe fruit, and ripe fruit). The result showed that EO content was highest in unripe fruits (0.18%) and lowest in the flowering stage (0.07%) in leaves, while extract yield was highest in leaves of the ripe fruit stage (14.65%) followed by the flowering stage in flowers (12.66%). Flowering stage leaves showed the highest total phenol (56.20 mg GAE/g) and flavonoid (17.10 mg QE/g) content, while the lowest concentrations were found in the ripe fruit stage of the leaves. EO analysis showed that methyl isothiocyanate reached the highest concentration in flowers at the flowering stage (41.6%), while isopropyl isothiocyanate reached the highest concentration in leaves at the ripe fruit stage (36.2%). Isobutyl isothiocyanate was found exclusively in fruits, with the highest concentration in ripe fruits (9.2%). Dimethyltrisulphide showed a maximum concentration in leaves at the vegetative stage, decreasing by 76.6% as the plant developed towards the ripe fruit stage. The dominant phenolic acids varied between phenological stages: cinnamic acid at the vegetative stage; rosmarinic and cinnamic acids at the flowering stage in leaves; caffeic and cinnamic acids in flowers; vanillic, cinnamic, and rosmarinic acids at the unripe fruit stage in leaves and fruits; and rosmarinic, cinnamic, and vanillic acids in ripe fruits. The results indicate that harvesting C. spinosa at the vegetative stage and in the leaves of the flowering stage is optimal for maximum secondary metabolite yield, providing valuable guidance for growers targeting food and pharmaceutical applications.