Metabolomics analysis of three Artemisia species in the Tibet autonomous region of China

BACKGROUND

The Artemisia species are widely distributed around the world, and have found important usage in traditional medicinal practice. This study was designed to investigate the metabolites of Tibetan Artemisia species and understand the metabolic pathways.

METHODS

The metabolites from three Artemisia species in Tibet, were analyzed using LC-MS/MS. The differential metabolites were classified and analyzed by principal component analysis (PCA), partial least squares analysis and hierarchical clustering. KEGG Pathway enrichment analysis was used to identify the key metabolic pathways involved in the differential metabolites of three Artemisia species.

RESULT

The metabolites of three Artemisia species were analyzed. Under the positive ion mode in LC-MS/MS, 262 distinct metabolites were differentially detected from Artemisia sieversiana and Artemisia annua, 312 differential metabolites were detected from Artemisia wellbyi and Artemisia sieversiana, 306 differential metabolites were screened from Artemisia wellbyi and Artemisia annua. With the negative ion mode, 106 differential metabolites were identified from Artemisia sieversiana and Artemisia annua, 131 differential metabolites were identified from Artemisia wellbyi and Artemisia sieversiana,133 differential metabolites were differentially detected from Artemisia wellbyi and Artemisia annua. The selected differential metabolites were mainly organic acids and their derivatives, ketones, phenols, alcohols and coumarins. Among these natural compounds, artemisinin, has the highest relative content in Artemisia annua.

CONCLUSIONS

This is the first reported attempt to comparatively determine the types of the metabolites of the three widely distributed Artemisia species in Tibet. The information should help medicinal research and facilitate comprehensive development and utilization of Artemisia species in Tibet.

Sesquiterpenes from Artemisia Sieversiana and their anti-inflammatory activities

Eight undescribed sesquiterpenes, including three dimeric guaianolides and five sesquiterpens, together with ten known ones, were isolated from the aerial parts of Artemisia sieversiana. Their structures were elucidated by extensive spectroscopic techniques and ECD calculation. The isolated compounds were tested for their anti-inflammatory effects against IL-1β, IL-6 and TNF-α in LPS-induced RAW 264.7 cells. Compounds 4, 9, 12, 15, 16 and 17 showed potent anti-inflammatory activities.

Dibenzocyclooctadiene lignans from Artemisia sieversiana and their anti-inflammatory activities

Two previously undescribed dibenzocyclooctadiene lignans, named sieverlignans D-E (1-2), as well as eight known ones (3-10), were isolated from the aerial parts of Artemisia sieversiana. Their structures were elucidated from extensive spectroscopic analysis, including HRMS, NMR and electronic circular dichroism (ECD) experiments. This study is the first to report dibenzocyclooctadiene lignans in the genus Artemisia and this plant. All the compounds were evaluated for their anti-neuroinflammatory activities on the lipopolysaccharides (LPS)-induced nitric oxide production in BV-2 murine microglial cells. Compounds 1 and 6 exhibited the moderate activities with their IC₅₀ values of 47.7 and 21.9 μM, compared to a positive control quercetin with the IC₅₀ value of 16.0 μM.

Chemical composition and phytotoxic activity of the essential oil of Artemisia sieversiana growing in Xinjiang, China

The chemical profile and phytotoxic activity of the essential oil extracted from Artemisia sieversiana was investigated. In total 17 compounds were identified by GC/MS, representing 99.17% of the entire oil, among which α-thujone (64.46%) and eucalyptol (10.15%) were the most abundant constituents. The major components, their mixture as well as the essential oil exhibited significant phytotoxic activity against Amaranthus retroflexus, Medicago sativa, Poa annua and Pennisetum alopecuroides, with their IC₅₀ values ranged from 1.55 ∼ 6.21 mg/mL (α-thujone), 1.42 ∼ 17.81 mg/mL (eucalyptol), 0.23 ∼ 1.05 mg/mL (the mixture), and 1.89 ∼ 4.69 mg/mL (the essential oil) on the four tested species. The mixture of the major constituents exerted more potent effect compared with each individual compound, indicating the possible involvement of synergistic effect of these two compounds.

Isolation and evaluation of trypanocidal activity of sesquiterpenoids, flavonoids, and lignans in Artemisia sieversiana collected in Mongolia

Artemisia sieversiana is an annual herbaceous plant distributed throughout Central and East Eurasia and is regarded as an undesirable forage plant in Mongolia. It affects livestock, so information about its chemical composition is needed. We isolated three new sesquiterpenoids (1-3) and known compounds from A. sieversiana and investigated their activities. The absolute configuration of 1 was established using single-crystal X-ray diffraction crystallography, and its configuration differed from those of reported compounds with similar structures. Two additional new sesquiterpenoids (2 and 3) with similar structures were identified, and their configurations were determined. The trypanocidal activities of the isolated compounds (1-18) against Trypanosoma congolense and the pathogen responsible for fatal trypanosomosis in animals were estimated. Flavonoids and lignans were identified as active compounds with IC₅₀ values ranging from 2.9 to 90.2 µM.

IN WESTERN PAMIR

Polyphenols content and antioxidant activity in Artemisia sieversiana Willd. were investigated in relation to the altitude of the plant growth in the Western Pamir region. Antioxidant activity generally correlated with the polyphenols content. However, no significant association was found between an altitude of the sample collection and polyphenols content or antioxidant activity.