The medicinal plant yarrow (Achillea millefolium L.) belongs to the Asteracea family. It is being used in the pharmacological, food, and cosmetic industry. The economic importance of yarrow resides in its essential oil (EO). This plant is used in traditional medicine as the EO has properties which range from antibacterial, antifungal, anti-inflammatory, anti-oxidant and antitumor activities. The objective of this study was to identify chemical components and EO content of yarrow, as well as its antimicrobial activity against some micro-organisms in vitro. The fresh leaves were collected in a morning in October (2018) at the UNIPAR Medicinal Plants Garden, Umuarama-Paraná State, Brazil. The EO was obtained by hydrodistillation of the modified Clevenger type. After that, the content (m/m%) was calculated. The chemical composition of the EO was identified by gas chromatography/mass spectrometry (GC/MS). The minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC) and minimal fungicidal concentration (MFC) were determined by a microdilution method in 96-well microtitre plates and effect of EO was assessed on four micro-organisms (Candida albicans, Staphylococcus epidermidis, Escherechia coli and Klebsiella pneumoniae). The EO content (yield) in the plant shoots was 0.4% (four grams of EO kg-1 of plant fresh shoots) and presented 20 chemical compounds such as α-farnesene (31.66%), followed by chamazulene (17.17%), β-caryophyllene (10.27%) and sabinene (8.77%). The majority class was hydrocarbon sesquiterpene with 74.29%. The antimicrobial activity tests showed that the EO had low antimicrobial activity against the analyzed species with MIC for all species above 1.5 mg mL-1. It was concluded that the EO content was 0.4%. The major component was α-farnesene (31.66%) and EO presented low MIC.

Momordica charantia commonly known as bitter melon/gourd, a member of Cucarbitaceae. Qualitative phytochemical analysis of Momordica charantia confirms the presence of photochemicals like flavonoids, saponins, terpenoids, coumarins, emodins, alkaloids, proteins, etc. HPLC is a simple, accurate and selective technique for separation and quantification of anthraquinone and flavonoid and phenols from leaf sample of bitter gourd. The most common method for chromatographic determination of anthraquinone is the HPLC method. Anthraquinones are a class of natural products encompassing several hundreds of compounds, differing in the nature and positions of substituent groups. Many anthraquinones have potential therapeutic value, since antimicrobial, insecticidal, antitumor, anticongestive, hypotensive and sedative properties have been assigned to these compounds.

The abscisic acid content of the mature shoot tissue of vigorous Prunus avium, medium sized Prunus cerasus and dwarfing Prunus cerasus self (S) was estimated by spectropolarimetry and gas chromatography. There is no correlation between the levels of ABA found in the tissue and the dwarfing potential of the trees investigated. However, Prunus avium stem tissue shows the lowest sensitivity to ABA, whereas the explants of normal and dwarfing Prunus cerasus exhibit a stronger inhibition.