Antibacterial, antioxidant and cytotoxic activities of extracts of Conyza canadensis (L.) Cronquist growing in Tunisia

Conyza canadensis from Jordan: Phytochemical Profiling, Antioxidant, and Antimicrobial Activity Evaluation

In this investigation, the chemical composition of the hydro-distilled essential oil (HD-EO), obtained from the fresh aerial parts (inflorescence heads (Inf), leaves (L), and stems (St)) of Conyza canadensis growing wild in Jordan was determined by GC/MS. Additionally, the methanolic extract obtained from the whole aerial parts of C. canadensis (CCM) was examined for its total phenolic content (TPC), total flavonoids content (TFC), DPPH radical scavenging activity, iron chelating activity and was then analyzed with LC-MS/MS for the presence of certain selected phenolic compounds and flavonoids. The GC/MS analysis of CCHD-EOs obtained from the different aerial parts revealed the presence of (2E, 8Z)-matricaria ester as the main component, amounting to 15.4% (Inf), 60.7% (L), and 31.6% (St) of the total content. Oxygenated monoterpenes were the main class of volatile compounds detected in the Inf-CCHD-EO. However, oils obtained from the leaves and stems were rich in polyacetylene derivatives. The evaluation of the CCM extract showed a richness in phenolic content (95.59 ± 0.40 mg GAE/g extract), flavonoids contents (467.0 ± 10.5 mg QE/ g extract), moderate DPPH radical scavenging power (IC50 of 23.75 ± 0.86 µg/mL) and low iron chelating activity (IC50 = 5396.07 ± 15.05 µg/mL). The LC-MS/MS profiling of the CCM extract allowed for the detection of twenty-five phenolic compounds and flavonoids. Results revealed that the CCM extract contained high concentration levels of rosmarinic acid (1441.1 mg/kg plant), in addition to caffeic acid phenethyl ester (231.8 mg/kg plant). An antimicrobial activity assessment of the CCM extract against a set of Gram-positive and Gram-negative bacteria, in addition to two other fungal species including Candida and Cryptococcus, showed significant antibacterial activity of the extract against S. aureus with MIC value of 3.125 µg/mL. The current study is the first phytochemical screening for the essential oil and methanolic extract composition of C. canadensis growing in Jordan, its antioxidant and antimicrobial activity.

Phytochemical Profiles, Antioxidant, Cytotoxic, and Anti-Inflammatory Activities of Traditional Medicinal Plants: Centaurea pichleri subsp. pichleri, Conyza canadensis, and Jasminum fruticans

Centaurea pichleri subsp. pichleri, Conyza canadensis, and Jasminum fruticans are traditionally used plants grown in Turkey. Methanol extracts were obtained from these plants and pharmacological activity studies and phytochemical analyses were carried out. To evaluate the phytochemical composition, spectrophotometric and chromatographic techniques were used. The extracts were evaluated for antioxidant activity by DPPH^●, ABTS^●+ radical scavenging, and FRAP assays. The cytotoxic effects of the extracts were investigated on DU145 prostate cancer and A549 lung cancer cell lines. The anti-inflammatory effects of extracts were investigated on the NO amount, TNF-α, IFN-γ, and PGE 2 levels in lipopolysaccharide-stimulated Raw 264.7 cells. The richest extract in terms of phenolic compounds (98.19 ± 1.64 mg_GAE/g_extract) and total flavonoids (21.85 ± 0.64 mg_CA/g_extract) was identified as C. pichleri subsp. pichleri methanol extract. According to antioxidant activity determinations, the C. pichleri subsp. pichleri extract was found to be the most active extract. Finally, the C. pichleri subsp. pichleri methanol extract was revealed to be the most effective inhibitor of viability in the cytotoxic activity investigation, and the extract with the best anti-inflammatory action. The findings point to C. pichleri subsp. pichleri as a promising source of bioactive compounds in the transition from natural sources to industrial uses, such as new medications, cosmeceuticals, and nutraceuticals.

Sesquiterpenoids from the aerial parts of Conyza japonica and their inhibitory activity against nitric oxide production

Four new sesquiterpenoids, conyterpenols A - D (1-4), along with nineteen known analogues (5-23) were isolated from the aerial parts of Conyza japonica. The structures of 1-4 were determined through spectroscopic analysis, while their absolute configurations were determined by comparison of calculated and experimental electronic circular dichroism (ECD) spectra. Conyterpenol D (4) was a new type of sesquiterpenoid with a seven-membered lactone ring. Compounds 1-23 were evaluated for their inhibitory activity against LPS-induced nitric oxide production in RAW264.7 macrophages and cytotoxicity against human hepatoma cell line (HepG2) and human breast adenocarcinoma cell line (MCF-7). Compounds 3, 4, and 12 displayed moderate inhibition against NO production with IC₅₀ values in the range of 26.4-33.6 μM. And all compounds showed no obvious cytotoxicity against these two cancer cell lines at 100 μM.

A review of Tunisian medicinal plants with anticancer activity

Cancer is a major public health problem in the world. The use of the medicinal plants in cancer prevention and management is frequent in Africa, especially in Tunisia, and it is transmitted from generation to generation within cultures. Many previous studies showed that a wide range of Tunisian medicinal plants exerted cytotoxic and anticancer activity. A comprehensive review was conducted to collect information from scientific journal articles, including indigenous knowledge researches, about Tunisian medicinal plants used for the prevention and management of cancer. The aim of this review article is to provide the reader with information concerning the importance of Tunisian medicinal plants in the prevention and management of cancer and to open the door for the health professionals and scientists working in the field of pharmacology and therapeutics to produce new drug formulations to treat different types of cancer.

Chemical Composition and Biological Activity of Conyza Bonariensis Essential Oil Collected in Mérida, Venezuela

The essential oil from aerial parts of Conyza bonariensis (L) Cronquist collected in Mérida was obtained by hydrodistillation and analysed by GC/MS. The major components were trans-β-farnesene (37.8%), trans-ocimene (20.7%) and β-sesquiphellandrene (9.8%). Cytotoxicity assay was also performed with the essential oil against HeLa (cervix carcinoma), A-459 (lung carcinoma) and MCF-7 (breast adenocarcinoma) human cell lines and against normal Vero cells (African green monkey kidney) with IC50 values ranging from 1.4 to 45.8 μg/mL. Additionally, the essential oil presented a significant bactericidal effect against Bacillus cereus, while a moderate activity was observed against Staphylococcus epidermidis and Candida albicans.