This study reports on the optimization of a microwave-assisted distillation process to obtain Dong Van marjoram essential oil, and the determination of its composition, content of constituents, and cytotoxic and antimicrobial activities. Using the response surface method (RSM), the optimal essential oil distillation conditions were determined as material size 0.74 (cm), water to material ratio 4.14:1 (mL/g), microwave power 302.4 (W), and distillation time 2.1 hours. At optimal conditions, the mass of Dong Van marjoram essential oil obtained was 0.887 ± 0.007 g, corresponding to a content of 0.6% essential oil in the material. GC-MS and GC-FID methods showed that the main chemical constituents of Dong Van marjoram essential oils obtained were rosefuran epoxide (44.9%), caryophyllene (10.8%), germacrene D (2.6%), and α-humulene (1.3%). The essential oil exhibited moderate inhibition against both tested cancer cell lines, with IC50 values of 23.9 µg/mL (for PC3) and 56.2 µg/mL (for A549). However, the oil exhibited strong effectiveness against three bacterial strains, Escherichia coli, Bacillus subtilis, and Staphylococcus aureus, and a yeast strain, Saccharomyces cerevisiae, with minimal inhibitory concentration (MIC) values ranged from 50 to 100 µg/mL.

Zanthoxylum nitidum (Roxb.) DC (Rutaceae) is a traditional medicine used for the treatment of various diseases like toothache, gingivitis, fever, colic vomiting, diarrhea, and cholera. Three new alkaloids, zanthocadinanine C (1), 7-methoxy-8-demethoxynitidine (2), and zanthonitiside I (3) were isolated from the stems and twigs of Z. nitidum. Their structures were determined on the basis of extensive spectroscopic, including 1-dimensional and 2-dimensional nuclear magnetic resonance and mass spectroscopy data. Compounds 1-3 were evaluated for cytotoxic activity against 5 human cancer cell lines, KB, MCF-7, LNCaP, HepG-2, and LU-1. Compound 2 showed significant cytotoxic activity against all tested human cancer cell lines with IC 50 values ranging from 10.3 to 12.6 µM.

Essential oils (EOs) from the stem barks, leaf petioles, fruit petioles, fresh leaves, and fresh and dried fruits of Zanthoxylum rhetsa were extracted by hydrodistillation. The volatile compounds of the products were analyzed by gas chromatography (GC-FID) and gas chromatography/mass spectrometry (GC/MSD). Monoterpene hydrocarbons formed the predominant fraction of all six EO samples, of which sabinene is one of the major components (from 12.37% to 41.13%). For the leaf petiole EO, limonene (25.01%), sabinene (14.56%), and linalool (12.63%) are the major constituents, while the main constituents of fruit petiole EO were terpinolene (19.66%), terpinen-4-ol (19.07%), and sabinene (17.83%). The major components of stem bark EO are terpinen-4-ol (18.23%), sabinene (12.37%), α-phellandrene (7.34%), β-phellandrene (6.32%), and γ-terpinene (6.12%), while sabinene (38.35%), terpinen-4-ol (13.71%), γ-terpinene (6.47%), and limonene (6.02%) are the major constituents of fresh leaf EO. For the EOs of dried fruits and fresh fruits, sabinene, terpinolene, limonene, and terpinen-4-ol are the major constituents. The essential oils were also tested for their cytotoxic and antimicrobial activities. The results revealed that six EOs at concentrations of 50 μg/mL exhibited inhibitory activity against at least one tested cancer cell line but were nontoxic on Vero normal cells. Most EOs showed moderate antimicrobial activity against F. oxysporum; however, there were no obvious activity against B. subtilis and S. aureus.

Lemongrass oil contains many useful aromatic compounds, some of which have strong deodorizing and antibacterial properties (citral and geraniol). The ingredient with the highest content in citronella oil is Citral (accounting for more than 80% of citronella oil content), which plays a key role in functionalities of disinfectants, biocides, odorants and insecticides. This study aims to incorporate lemongrass essential oil into a wax product to extend the application of the oil. The effect of factors that affects the process of creating aromatic wax was investigated. The yield of essential oils obtained by steam distillation was 0.29%. The effect of factors that affects the process of creating aromatic wax was investigated. The formula of aromatic wax contains 4.5% Stearic acid, 2.7% NaOH, 88.6% Alcohol 20°, 2.4% PEG-40, 2% Lemongrass Essential oil. The results indicate that the lemongrass essential oil causes no significant detriment to the beneficial properties of the obtained aromatic wax.