The mandarin (Citrus reticulata Blanco) essential oil is well-known for bactericidal, antioxidant and anti-cancer properties. Thus, an effective extraction method is required to obtain high oil yield with an abundant content of bioactive compounds. In the present study, the chemical profiles of essential oils extracted from the peels of Mandarin) via hydrodistillation (HD), microwave-assisted hydrodistillation (MAHD) and microwave extraction (ME) were reported in this study. Extraction techniques were carried out at their optimal conditions and the results were compared with each other. Gas chromatography-mass spectrometry (GC-MS) was employed to perform compositional determination. A total of 5 components was determined, accounting for almost 100% of total oil content. The extraction efficiencies were 3.6%, 6.8%, and 5.5% respectively obtained from HD, MAHD and ME. The results showed that MAHD seemed to result in higher yield and essential oil with identical chemical composition and quality in comparison with those of other methods, suggesting that MAHD was a potential alternative method to HD to reduce the time and cost of the extraction process.

A new oxygenated spiroketone, isodonspiroketone (1), and 4 known ones (2-5) were isolated from the whole plant of Isodon ternifolius (D.Don) Kudô. The structure of isodonspiroketone (1) was determined by nuclear magnetic resonance, mass spectroscopy, and circular dichroism spectral data. Compound 3 has not been previously isolated from I. ternifolius. Their cytotoxic activities were evaluated against A549, HepG2, and MDA-MB-231 cancer cell lines in vitro. New compound (isodonspiroketone, 1) showed moderate cytotoxic activities against A549, HepG2, and MDA-MB-231 cancer cell lines with half-maximal inhibitory concentration values of 23.84 ± 2.73, 27.77 ± 3.01, and 17.26 ± 1.61 μM, respectively; meanwhile, the others were inactive.

No abstract