This study illustrates a profile of some essential and non-essential elements (Na, K, Mg, Ca, Cu, Zn, Mn, Fe, Pb, Cr, Cd, Co, Al, and Sn) in the aerial parts of six medicinal plants, i.e. Coriandrum sativum L., Mentha spicata L., Papaver somniferum L., Calotropis gigantean (L.) Dryand., Withania coagulans (Stock) Dunal, and Fagonia arabica L. widely consumed in district Peshawar, the capital city of Khyber Pakhtunkhwa, Pakistan. The samples were converted into liquid state via wet digestion method and analyzed for elemental composition by using atomic absorption spectrometry. After determining the concentration, hazard quotient (HQ) was calculated for the elements having available maximum permissible limit set by FAO/WHO or any other agency for 50 mg daily intake of the herbal plants by a person of body mass 70 kg. K/Na ratio for the studied plants varied between 14.88:1 and 113.75:1 which was in agreement with the reported permissible range. The amount of Mg, Ca, Cu, and Co was within the permissible limit in all the enlisted plants. However, the HQ value for Mg and Ca was greater than the safe limit for some of the plants. The concentration and HQ value of Zn, Mn, Fe, Pb, Cr, and Cd was beyond the permissible and unsafe limits for almost all the plants. This study suggests that the plants of this area must be pretreated for lessening the concentration of some elements before consumption.

This study provides, for the first time, data regarding levels of toxic metals (Hg, Cd, and Pb) and organochlorine compounds (PCBs and DDTs) in various aromatic herbs as rosemary (Rosmarinus officinalis), sage (Salvia officinalis), laurel (Laurus nobilis), oregano (Origanum vulgare), and spearmint (Mentha viridis) collected in some towns of the Southern Italy with different anthropogenic and population pressure. Metal and organochlorine compound concentrations were determined using atomic absorption spectrophotometer and gas-chromatography mass spectrometer (GC/MS), respectively. Pb emerged as the most abundant element, followed by Cd and Hg, while between organochlorine compounds, PCB concentrations were higher than those of DDTs. The pollutant concentrations were found to vary depending on the different herbs. The highest Pb levels were observed in rosemary (1.66 μg g⁻¹dry weight) and sage (1.41 μg g⁻¹dry weight), this latter showing also the highest Cd concentrations (0.75 μg g⁻¹dry weight). For PCBs, the major concentrations were found in rosemary (2.75 ng g⁻¹dry weight) and oregano (2.39 ng g⁻¹dry weight). The principal component analysis applied in order to evaluate possible similarities and/or differences in the contamination levels among sampling sites indicated differences area-specific contamination.

Chemical composition and antifungal activity of essential oils of Algerian Mentha species were studied. Chemical compositions of different Mentha species oils (Mentha rotundifolia, M. spicata, M. pulegium, and M. piperita) were investigated by capillary GC and GC/MS, and their antifungal activities were evaluated by means of paper disc diffusion method and minimum inhibitory concentration (MIC) assays. In total, 98 components from all Mentha species were identified. All oils were rich in monoterpene-oxygenated components. In addition, we reported fumigant antifungal activity of Algerian Mentha essential oils against four fungi: Botrytis cinerea, Penicillium expansum, Monilinia laxa, and M. fructigena. All oils demonstrated very good inhibition especially against B. cinerea, M. laxa, and M. fructigena. Both Monilinia fungi were extremely sensitive to all Algerian Mentha oils, which suggests that Mentha essential oils have the potential to be used as bio-pesticides to protect fruit trees, such as apple and pear trees, and provides an alternative to chemical pesticides.