ABSTRACT
Mikania micrantha Kunth is widely known as potential herbal medicine, although it is an invasive alien species in Southeast Asia. In this study, the essential oils from leaves and stems of M. micrantha were extracted by hydrodistillation method, and the chemical profiles of essential oils were then analysed by gas chromatography (GC) and gas chromatography coupled with mass spectrometry (GC/MS). It was found that there were similarities and differences in chemical compositions and their percentage between the essential oils obtained from these two parts. The dominant components of leaves essential oil are ß-Cubebene, Germacrene D, and α-Zingiberene, accounting for 11.34%, 10.96%, and 10.76%, respectively. Additionally, the major components of stems essential oils are D-Limonene (16.99%), ß-Pinene (7.91%), and α-Zingiberene (7.26%). The research sheds fresh light on the chemical makeup of M. micrantha essential oils, emphasising their potential for the future.
ABSTRACT
To date, determining with high accuracy the optical parameters (extinction coefficient k and refractive index n) of a slab from the sole transmittance data requires an inverse method based on numerical iteration procedures. In this paper, we propose a new inverse analytical method of extracting (k, n) without numerical iterative processes. The high accuracy of this new inverse method is assessed, and as an application example, the optical parameters of CaF2 and Si substrates are determined in the IR spectral range of 4-8 µm.
ABSTRACT
Celastrus hindsii is a potential source of flavonoids with biological activities. This study aimed to develop an ultrasound-assisted technique for extracting flavonoids from leaves of C. hindsii. Response surface methodology was employed to optimize the extraction conditions for maximizing the total flavonoid content (TFC). A maximum TFC of 23.6 mg QE/g was obtained under the extraction conditions of ultrasonic power of 130 W, extraction temperature of 40°C, extraction time of 29 min, and ethanol concentration of 65%. The flavonoid-rich extracts were then studied for their antioxidant and anticancer activities. The results showed that the C. hindsii leaf extract exhibited potent radical scavenging activities against DPPH (IC50 of 164.85 µg/mL) and ABTS (IC50 of 89.05 µg/mL). The extract also significantly inhibited the growth of 3 cancer cell lines MCF7, A549, and HeLa with the IC50 values of 88.1 µg/mL, 120.4 µg/mL, and 118.4 µg/mL, respectively. Notably, the extract had no cytotoxicity effect on HK2 normal kidney cell line. This study suggests that flavonoid-rich extract is a promising antioxidant and anticancer agent and that ultrasound-assisted extraction is an efficient method for extracting flavonoids from C. hindsii leaves.
