Chemical Profiling and Biological Activity of Extracts from Nine Norwegian Medicinal and Aromatic Plants

Transcriptome and metabolome analyses reveal chlorogenic acid accumulation in pigmented potatoes at different altitudes

Pigmented potato tubers are abundant in chlorogenic acids (CGAs), a metabolite with pharmacological activity. This article comprehensively analyzed the transcriptome and metabolome of pigmented potato Huaxingyangyu and Jianchuanhong at four altitudes of 1800 m, 2300 m, 2800 m, and 3300 m. A total of 20 CGAs and intermediate CGA compounds were identified, including 3-o-caffeoylquinic acid, 4-o-caffeoylquinic acid, and 5-o-caffeoylquinic acid. CGA contents in Huaxinyangyu and Jianchuanhong reached its maximum at an altitude of 2800 m and slightly decreased at 3300 m. 48 candidate genes related to the biosynthesis pathway of CGAs were screened through transcriptome analysis. Weighted gene co-expression network analysis (WGCNA) identified that the structural genes of phenylalanine deaminase (PAL), coumarate-3 hydroxylase (C3H), cinnamic acid 4-hydroxylase (C4H) and the transcription factors of MYB and bHLH co-regulate CGA biosynthesis. The results of this study provide valuable information to reveal the changes in CGA components in pigmented potato at different altitudes.

Integrated GC-MS and UPLC-ESI-QTOF-MS based untargeted metabolomics analysis of in vitro raised tissues of Digitalis purpurea L

Digitalis purpurea L. is one of the important plant species of Nilgiris, Kashmir and Darjeeling regions of India, belonging to the family Plantaginaceae, with well-known pharmacological applications. In the present investigation, an in vitro culture technique of indirect shoot organogenesis of D. purpurea is being explored; the biochemical attributes, the antioxidant activities and the metabolomic analyses were made by utilizing untargeted Gas Chromatography-Mass Spectrometry (GC-MS) and Ultra Performance Liquid Chromatography coupled with electronspray ionization/quadrupole-time-of-flight-mass spectrometry (UPLC-ESI-QTOF-MS) approaches. Initially, the leaf explants were used for callus induction and proliferation and maximum callusing frequency (94.44%) and fresh biomass (4.9 g) were obtained on MS, fortified with 8.8 µM BAP (6-benzyl amino purine) + 0.9 µM 2,4-D (2,4-dichlorophenoxyacetic acid), subsequently shoot formation (indirect organogenesis) was noted on the same MS medium with a shoot induction frequency of 83.33%. Later on, the biochemical and antioxidant potential of in vivo-, in vitro grown leaf and leaf derived callus were assessed. Significantly higher total phenol, flavonoid, DPPH (2,2-diphenyl-1-picrylhydrazyl), POD (peroxidase) and SOD (superoxide dismutase) activities were noticed in in vitro grown callus and leaf tissues compared with field grown leaf. The GC-MS analysis of each methanolic extract (in vivo-, in vitro derived leaf and leaf derived callus) displayed the presence of more than 75 bioactive compounds viz loliolide, stigmasterin, alpha-tocopherol, squalene, palmitic acid, linoleic acid, beta-amyrin, campesterol etc. possessing immense therapeutic importance. The UPLC-MS based metabolite fingerprinting of each methanolic extracts were conducted in both positive and negative ionization mode. The obtained results revealed variation in phytochemical composition in field - and laboratory grown tissues, indicating the impact of in vitro culture conditions on plant tissues. The detected phytocompounds belongs to various classes such as flavonoids, steroids, terpenoids, carbohydrates, tannins, lignans etc. The medicinally important metabolites identified were 20, 22-dihydrodigoxigenin, digoxigenin monodigitoxoside, apigenin, luteolin, kaempferide, rosmarinic acid, nepitrin and others. The results of the present study suggest that in vitro culture of D. purpurea could successfully be utilized for the novel drug discovery by producing such important phytocompounds of commercial interest in shorter duration without harming the plants' natural population.

In Vitro and In Silico Anti-Glioblastoma Activity of Hydroalcoholic Extracts of Artemisia annua L. and Artemisia vulgaris L

Glioblastoma, the most aggressive and challenging brain tumor, is a key focus in neuro-oncology due to its rapid growth and poor prognosis. The C6 glioma cell line is often used as a glioblastoma model due to its close simulation of human glioma characteristics, including rapid expansion and invasiveness. Alongside, herbal medicine, particularly Artemisia spp., is gaining attention for its anticancer potential, offering mechanisms like apoptosis induction, cell cycle arrest, and the inhibition of angiogenesis. In this study, we optimized extraction conditions of polyphenols from Artemisia annua L. and Artemisia vulgaris L. herbs and investigated their anticancer effects in silico and in vitro. Molecular docking of the main phenolic compounds of A. annua and A. vulgaris and potential target proteins, including programmed cell death (apoptosis) pathway proteins proapoptotic Bax (PDB ID 6EB6), anti-apoptotic Bcl-2 (PDB ID G5M), and the necroptosis pathway protein (PDB ID 7MON), mixed lineage kinase domain-like protein (MLKL), in complex with receptor-interacting serine/threonine-protein kinase 3 (RIPK3), revealed the high probability of their interactions, highlighting the possible influence of chlorogenic acid in modulating necroptosis processes. The cell viability of rat C6 glioma cell line was assessed using a nuclear fluorescent double-staining assay with Hoechst 33342 and propidium iodide. The extracts from A. annua and A. vulgaris have demonstrated anticancer activity in the glioblastoma model, with the synergistic effects of their combined compounds surpassing the efficacy of any single compound. Our results suggest the potential of these extracts as a basis for developing more effective glioblastoma treatments, emphasizing the importance of further research into their mechanisms of action and therapeutic applications.

Highly oxidized flavones in Artemisia species - structure revisions and improved UHPLC-MSn analysis

In course of our studies of the aerial parts of Artemisia abrotanum the major methoxyflavonol could be isolated. However, by NMR structural analysis it became obvious that the substitution pattern in ring B differs from reports for casticin (2). The position of methoxyl and hydroxyl groups are interchanged, i.e., the major flavone is actually chrysosplenetin (1). Three structures in A. abrotanum and A. frigida had to be revised. Use of pyridine-d5 instead of DMSO‑d6 made the resolution of the B-ring 1H and 13C NMR signals possible and enabled correct structural assignment by 2D NMR experiments. Results from NMR structure elucidation for A. abrotanum were confirmed by LC-PDA-ESI-MSn analysis when a PFP (pentafluorophenyl) stationary phase with an optimized gradient elution was applied for separation of 1 and 2 instead of a corresponding C-18 phase. Electrospray mass spectrometry (positive and negative mode) with subsequent fragmentation (ESI-MSn) revealed distinctive mass spectral features of both compounds, especially at MS4 level. Several Artemisia extracts including A. annua were analysed on the PFP phase for the presence of 1 and 2.

Artemisia arborescens and Artemisia inculta from Crete; Secondary Metabolites, Trace Metals and In Vitro Antioxidant Activities

BACKGROUND

Currently, the use of medicinal plants has increased. Artemisia species have been used in several applications, including medicinal use and uses in cosmetics, foods and beverages. Artemisia arborescens L. and Artemisia inculta are part of the Mediterranean diet in the form of aqueous infusions. Herein, we aimed to compare the secondary metabolites of the decoctions and two different extracts (methanolic and aqueous-glycerolic) of these two species, as well as their antioxidant capacity and trace metal levels.

METHODS

Total phenolic, total flavonoid, total terpenes, total hydroxycinnamate, total flavonol, total anthocyanin contents and antioxidant/antiradical activity were determined, and GC/MS analysis was applied to identify and quantify phenolics and terpenoids. Trace metals were quantified with ICP-MS.

RESULTS

Aqueous-glycerolic extracts demonstrated higher levels of total secondary metabolites, greater antioxidant potential and higher terpenoid levels than decoctions and methanolic extracts. Subsequently, the aqueous-glycerolic extract of a particularly high phenolic content was further analyzed applying targeted LC-MS/MS as the most appropriate analytic tool for the determination of the phenolic profile. Overall, twenty-two metabolites were identified. The potential contribution of infusions consumption to metal intake was additionally evaluated, and did not exceed the recommended daily intake.

CONCLUSIONS

Our results support the use of these two species in several food, cosmetic or pharmaceutical applications.