Many species belonging to the genus Echinops are widely used in traditional medicine to treat infectious diseases and cancers. The present study aimed to evaluate the antibacterial and antiproliferative properties of Echinops lanceolatus Mattf. (Asteraceae). The activity of the methanolic extract and subsequent partition fractions was investigated against drug-resistant bacteria (Gram-negative and Gram-positive) and human tumor cell lines using broth microdilution and sulforhodamine B (SRB) assay, respectively. Our findings revealed weak to moderate antibacterial activities of tested extracts, with the recorded minimal inhibitory concentrations ranging from 256 to 1024 µg/mL. The ethyl acetate fraction (EL-EA) was found to be the most effective. Likewise, that fraction displayed strong antiproliferative potential with recorded IC₅₀ of 8.27 µg/mL and 28.27 µg/mL on A549 and HeLa cells, respectively. An analysis based on the ultra-performance liquid chromatography–electrospray ionization tandem mass spectrometry (UPLC–ESI–MS/MS) of the EL-EA fraction allowed the identification of 32 compounds, of which quinic acid and derivatives, cinnamic acid derivatives, dihydrokaempferol, naringenin-7-O-glucoside, apigenin-7-O-d-glucoside, naringin, apigenin, rhoifolin, coniferyl aldehyde, and secoisolariciresinol are well-known compounds of biological importance. This study is first to report on the biological activity and phytochemical profile of E. lanceolatus. We provide a baseline to consider E. lanceolatus as a valuable source of anti-infective and antiproliferative agents.

Hagenia abyssinica (Bruce) J. F. Gmel. is a multipurpose dioecious tree that has been used to treat various ailments, for example, the flowers of H. abyssinica have been widely used as a tea to treat intestinal parasites by local residents and the roots of H. abyssinica could also be used for anticancer purposes. Antioxidant activity could be one of the most important pathways to suppress cancer and there is hardly any information available on the specific chemical components corresponding to the bioactivities of H. abyssinica to date. The present study intended to screen and evaluate the antioxidant and anti-proliferative properties of five different fractions from H. abyssinica along with their corresponding total flavonoid and phenolic contents and then further identify those compounds with the most potent antioxidant and anti-proliferative activities using high performance liquid chromatography (HPLC) coupled to mass spectrometry (MS) and nuclear magnetic resonance (NMR). The total flavonoid and phenolic content assays showed that the ethyl acetate (EA) fraction of H. abyssinica had higher flavonoid and phenolic levels than the other four fractions. Furthermore, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) superoxide radical scavenging abilities, total antioxidant capacity (TAC) assay with 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid (ABTS), and ferric-reducing antioxidant power (FRAP) were measured to evaluate the antioxidant activities of the five fractions and some pure compounds isolated from the EA fraction, which displayed higher antioxidant properties than that of the other fractions. Caffeic acid from the EA fraction showed even stronger DPPH scavenging ability (IC₅₀ 7.858 ± 0.31 µg/mL) than that of Vc (IC₅₀ 8.27 ± 0.11 µg/mL) as the positive control. The anti-proliferative properties of four fractions and the ethanol extract were evaluated by the 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide (MTT) assay and the EA fraction exhibited higher anti-proliferative activities against three cancer cell lines than that of the other fractions. Additionally, the compounds with good antioxidant activity from the EA fraction of H. abyssinica were screened and identified using LC-MS and NMR and were also found to possess good anti-proliferative activity. In the MTT assay, the quercetin showed the strongest dose-dependent anti-proliferative activities to colon cancer cells (HT-29) and liver cancer cells (HepG2) among all of the compounds isolated. This study provided valuable information on the synergistic antioxidant and anti-proliferative properties of H. abyssinica.

Selaginella doederleinii Hieron. (S. doederleinii) is a traditional herb that is widely used in China to treat several ailments, but mainly cancer. Studies have been carried out to determine the phytochemicals ascribed to its pharmacological activity. However, both phytochemical and pharmacological profiles have not been fully explored as few compounds have been reported. This study evaluated the flavonoid content of the ethanol extract and its four fractions (petroleum ether, dichloromethane, ethyl acetate, and n-butanol) together with their antioxidant activity (DPPH and FRAP assays). Further, the antiproliferative activity was evaluated. Two new secondary metabolites (1 and 3) were isolated from S. doederleinii, which comprised of an apigenin skeleton with a phenyl attached at C-8 of ring A and an acetyl group. Additionally, other known metabolites 2 and 4–16 were isolated, whereby compounds 2, 4, 5, 8, 12, 15, and 16 were reported for the first time in this species. These compounds were evaluated for their antioxidative potentials by both DPPH and FRAP assays, and for their antiproliferative activities by the MTT assay on three human cancer cell lines: colon cancer (HT-29), cervical cancer (HeLa), and lung cancer (A549). Compound 7 exhibited the best activity on the three cancer cell lines (HT-29, HeLa, A549) by inhibiting the rate of growth of the cancer cells in a dose-dependent manner with IC₅₀ values of 27.97, 35.47, and 20.71 µM, respectively. The structure–activity relationship of the pure compounds was highlighted in this study. Hence, the study enriched both the phytochemical and pharmacological profiles of S. doederleinii.

Carissa spinarum has been traditionally used for the treatment of various diseases due to its different pharmacological activities. However, the active compounds responsible for its potentially specific activities have rarely been explored. To this end, the ethyl acetate (EA) fraction was screened out and selected for further phytochemical isolation because of its promising activities in preliminary 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and COX-2 inhibition assays. As a result, 10 compounds (1−10), including a new one (5), were isolated, with eight of these being identified as phenolic compounds, as expected. Compound 9 possessed an IC₅₀ value of 16.5 ± 1.2 µM, which was lower than that of positive control (vitamin C, 25.5 ± 0.3 µM) in the DPPH assay, and compounds 2, 6, 7 and 9 showed better total antioxidant capacity than vitamin C in the FRAP assay. Meanwhile, compounds 1−6 and 9 also had IC₅₀ values of less than 1.0 µM, which was even better than the positive control indomethacin in the COX-2 inhibition assay. In this context, compounds 2 and 9 were further evaluated to exhibit clear hepatoprotective activities by improving the L02 cell viability and reducing ROS production using a H₂O₂-induced L02 cell injury model. This study provides initial evidence revealing the most potent phenolic compounds from the root bark of C. spinarum responsible for its antioxidant, anti-inflammatory and hepatoprotective activities.

Warburgia ugandensis, also known as “green heart,” is widely used for the treatment of various diseases as a traditional ethnomedicinal plant in local communities in Africa. In this work, 9 and 12 potential superoxide dismutase (SOD) and xanthine oxidase (XOD) ligands from W. ugandensis were quickly screened out by combining SOD and XOD affinity ultrafiltration with LC-MS, respectively. In this way, four new lignanamides (compounds 11–14) and one new macrocyclic glycoside (compound 5), along with three known compounds (compounds 1, 3, and 7), were isolated and identified firstly in this species. The structures of the new compounds were elucidated by spectroscopic analysis, including NMR and UPLC-QTOF-MS/MS. Among these compounds, compound 14 showed the highest 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azinobis-(3-ethylbenzthiazoline)-6-sulfonic acid (ABTS) radical scavenging activities, and total ferric-reducing antioxidant power (FRAP) with IC₅₀ values of 6.405 ± 0.362 µM, 5.381 ± 0.092 µM, and 17.488 ± 1.625 mmol TE/g, respectively. Moreover, compound 14 displayed the highest inhibitory activity on cyclooxygenase-2 (COX-2) with IC₅₀ value of 0.123 ± 0.004 µM, and the ranking order of other compounds’ IC₅₀ values was 13 > 11 > 7 > 1 > 12. The present study suggested that lignanamides might represent interesting new characteristic functional components of W. ugandensis to exert remarkable antioxidant and anti-inflammatory activities. Moreover, compound 14, a new arylnaphthalene lignanamide, would be a highly potential natural antioxidant and anti-inflammatory agent from W. ugandensis.

Carissa spinarum Linn. has been utilized both in the food industry and as a traditional medicine for various ailments, while the responsible chemical components and action mechanisms of its antioxidative and hepatoprotective activities remain unclear. In this work, at least 17 quinic acid derivatives as potential ligands for the superoxide dismutase (SOD) enzyme from Carissa spinarum L. were screened out using the bio-affinity ultrafiltration with liquid chromatography mass spectrometry (UF–LC/MS), and 12 of them (1–12), including, three new ones (1–3), were further isolated by phytochemical methods and identified by high resolution electrospray ionization mass spectrometry (HR-ESI-MS) and extensive nuclear magnetic resonance (NMR) spectroscopic analysis. All of these isolated compounds were evaluated for their antioxidant activities by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric-reducing antioxidant power (FRAP) methods. As a result, compounds 4 and 6–11 displayed similar or better antioxidant activities compared to vitamin C, which is in good agreement with the bio-affinity ultrafiltration with SOD enzyme. Then, these compounds, 4 and 6–11, with better antioxidant activity were further explored to protect the L02 cells from H₂O₂-induced oxidative injury by reducing the reactive oxygen species (ROS) and Malondialdehyde (MDA) production and activating the SOD enzyme. To the best of our knowledge, this is the first report to use an efficient ultrafiltration approach with SOD for the rapid screening and identification of the SOD ligands directly from a complex crude extract of Carissa spinarum, and to reveal its corresponding active compounds with good antioxidative and hepatoprotective activities.