Phytochemistry and biological activity of Erigeron annuus (L.) Pers

Investigation Into the Impact of Solvents on the Phytochemical Composition, Antioxidant Capacities, and Antihyperglycemic Activities of Erigeron annuus (L.) Pers

This study aims to assess the phytochemical composition, antioxidant potential, and antidiabetic properties of Erigeron annuus (L.) Pers. The ethyl acetate fraction of Erigeron annuus leaves exhibited the highest extraction rate (22.42%). The preliminary qualitative phytochemical analysis in crude extract and fractions is often performed using chemical tests. For quantitative analysis, spectrophotometric methods are widely used to estimate the concentration of phytochemicals. The antioxidant properties were evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and the ferric reducing antioxidant power (FRAP) assay, which measures the reduction of Fe3+ to Fe2+. Qualitative screening revealed the presence of tannins, flavonoids, phenols, saponins, and alkaloids. Notably, the ethyl acetate fraction showed significantly (p < 0.05) higher total phenolic content (70.01 ± 1.1 mg/g) and total flavonoid content (80.29 ± 1.03 mg/g). This fraction also demonstrated substantial α-amylase inhibitory activity and antioxidant potential, suggesting the ability of polyphenols to reduce α-amylase activity. The α-amylase inhibition (23.15 ± 1.22% to 67.31 ± 2.01%) activity and IC50 value (40.59 ± 0.03  μg/mL) were notably higher in the ethyl acetate fraction compared with the standard drug metformin (19.88 ± 1.51  μg/mL). Erigeron annuus ethyl acetate fraction exhibited significantly higher glucose levels (10.88% ± 1.29% to 65.11 ± 0.94%) and conducted a lipid peroxidation experiment utilizing egg yolk as the source of lipids with high content. The most bioactive fraction was evaluated for cytotoxicity against the HEK293 cell line. The cytotoxicity assay revealed that 50% cell viability was observed at a concentration of 50 μg/mL, indicating that the plant extract is nontoxic at concentrations below this threshold. Furthermore, the dominant fraction was further investigated using liquid chromatography-mass spectroscopy and high-performance thin-layer chromatography techniques from the selected plant. Moreover, an in vivo study will be performed to evaluate the antidiabetic efficacy of Erigeron annuus, isolate and characterize its bioactive components, and examine its molecular mechanism of action to improve its therapeutic applicability.

Chemical Constituents, Biological Activities and Molecular Docking Studies of Root and Aerial Part Essential Oils from Erigeron sublyratus Roxb. ex DC. (Asteraceae)

In this work, the volatile components of Erigeron sublyratus essential oils and their anti-inflammatory and cytotoxic activities were investigated for the first time. Gas chromatography-mass spectrometry (GC-MS) analysis identified 28 components in the root and aerial part essential oils. The main components included cis-lachnophyllum ester (53.4-64.2 %), germacrene D (5.6-8.6 %), trans-β-ocimene (2.6-7.5 %), β-caryophyllene (4.7-6.8 %), β-myrcene (2.0-6.3 %), and (E)-β-farnesene (4.8-5.0 %). The aerial part essential oil inhibited nitric oxide (NO) production on LPS-induced RAW 264.7 cells, with an IC50 value of 1.41±0.10 μg/mL. In addition, both root and aerial part essential oils exhibited cytotoxic activity against MCF-7, SK-LU-1, and HepG2. Molecular docking simulation results revealed that (E)-β-farnesene strongly binds to the VEGFR-2 enzyme, while δ-cadinene has a high affinity to the COX-2 enzyme via hydrophobic interactions. These findings proposed that E. sublyratus essential oils can be exploited for their anti-inflammatory and anti-cytotoxicity potential.

Investigating the antiviral activity of Erigeron annuus (L.) pers extract against RSV and examining its active components

ETHNOPHARMACOLOGICAL RELEVANCE

The plants in the genus Erigeron are known to exhibit antiviral activities, including those against the respiratory syncytial virus (RSV). In traditional medicine Erigeron annuus (L.) Pers (EA) has been used in the treatment of pulmonary diseases and acute infectious hepatitis.

AIM OF THIS STUDY

The aim of this study is to determine the optimum extraction method to produce the most potent anti-RSV extract, elucidate its mode and mechanisms of antiviral activity in both in vitro and in vivo models, and identify the chemical structures of the bioactive compounds.

MATERIALS AND METHODS

The whole plant of EA was extracted with ethyl acetate, methanol, ethanol, water, aqueous methanol (60, 80% and 100%) and aqueous ethanol (50, 75% and 95%) using maceration, reflux, and ultrasound-assisted extraction methods. The antiviral activities of the extracts were determined in vitro. The in vitro antiviral activities of the extracts were determined using Hep-2 cells. Four in vitro experiments were performed to determine the mode of antiviral activity of the most active extract, ethyl acetate fraction (EAE) of Erigeron annuus whole plant extract prepared by refluxing with 50% ethanol, by examining its ability to inactivate the virus directly, inhibit viral adsorption and penetration, inhibit viral replication and preventive effect. The effect of temperature and duration of treatment on these modes of action was also determined. The antiviral activity of the EAE was also assessed in vivo in a mouse model. The lung index, viral load, and lung tissue histology were measured. qRT-PCR and ELISA studies were performed to determine the expression of key genes (TLR-3 and TLR-4) and proteins (IL-2, IFN-γ, and TNF-α) related to RSV infection. The most active antiviral compound was isolated using chromatography techniques, and its chemical structure was identified through electrospray triple quadrupole mass spectroscopy and nuclear magnetic resonance spectroscopy.

RESULTS

The EAE was the most active on RSV. In vitro experiments showed that the antiviral activity of EAE is via direct inactivation, inhibition of entry, and inhibition of the proliferation of the virus. In vivo experiments showed that the EAE effectively inhibited the proliferation of RSV in the lungs and alleviated the lung tissue lesions in RSV-infected mice. The antiviral activity of the EAE is mediated by downregulating the expression of TLR3 and TLR4 in the lung, upregulating the expression of IL-2 and IFN-γ, and downregulating the expression of TNF-α. Apigenin 7-O-methylglucuronide was found to be a major bioactive compound in EAE.

CONCLUSIONS

The results of this study confirmed the antiviral activity of EA by inactivating, inhibiting the entry, and inhibiting the proliferation of RSV. The activity is mediated by regulating the immunity and inflammatory mediators. Apigenin 7-O-methylglucuronide is the bioactive compound present in EA.

Pyromeconic acid-enriched Erigeron annuus water extract as a cosmetic ingredient for itch relief and anti-inflammatory activity

Erigeron annuus (EA), traditionally used to treat disorders such as diabetes and enteritis, contains a variety of chemicals, including caffeic acid, flavonoids, and coumarins, providing antifungal and antioxidative benefits. However, the ingredients of each part of the EA vary widely, and there are few reports on the functionality of water extracts in skin inflammation and barrier protection. We assessed the therapeutic properties of the extract of EA without roots (EEA) and its primary ingredient, pyromeconic acid (PA), focusing on their antihistamine, anti-inflammatory, and antioxidative capabilities using HMC-1(human mast cells) and human keratinocytes (HaCaT cells). Our findings revealed that histamine secretion, which is closely related to itching, was notably reduced in HMC-1 cells following pretreatment with EEA (0.1% and 0.2%) and PA (corresponding concentration, 4.7 of 9.4 µg/mL). Similarly, they led to a marked decrease in the levels of pro-inflammatory cytokines, including IL-1β, IL-8, IL-6, and IFN-γ. Furthermore, EA and PA enhanced antioxidant enzymes, such as superoxide dismutase (SOD) and catalase (CAT), reduced malondialdehyde (MDA) production, and showed reactive oxygen species (ROS) scavenging activity in HaCaT cells. Moreover, at the molecular level, elevated levels of the pro-inflammatory cytokines IL-1β, IL-6, TARC, and MDC induced by TNF-α/IFN-γ in HaCaT cells were mitigated by treatment with EEA and PA. We also revealed the protective effects of EEA and PA against SDS-induced skin barrier dysfunction in HaCaT cells by enhancing the expression of barrier-related proteins. Using NanoString technology, a comprehensive analysis of gene expression changes indicated significant modulation of autoimmune and inflammatory genes by EEA and PA. In summary, this study suggests that EEA and the corresponding concentration of PA as an active ingredient have functional cosmetic applications to alleviate itching and improve skin health.