Preparative isolation of six anti-tumour biflavonoids from Selaginella doederleinii Hieron by high-speed counter-current chromatography

Studying the effects of secondary metabolites isolated from Cycas thouarsii R.Br. leaves on MDA-MB-231 breast cancer cells

The various therapeutic drugs that are currently utilized for the management of cancer, especially breast cancer, are greatly challenged by the augmented resistance that is either acquired or de novo by the cancer cells owing to the long treatment periods. So, this study aimed at elucidating the possible anticancer potential of four compounds 7, 4', 7'', 4'''-tetra-O-methyl amentoflavone, hesperidin, ferulic acid, and chlorogenic acid that are isolated from Cycas thouarsii leaves n-butanol fraction for the first time. The MTT assay evaluated the cytotoxic action of four isolated compounds against MDA-MB-231 breast cancer cells and oral epithelial cells. Interestingly, ferulic acid revealed the lowest IC50 of 12.52 µg/mL against MDA-MB-231 cells and a high IC50 of 80.2 µg/mL against oral epithelial cells. Also, using an inverted microscope, the influence of ferulic acid was studied on the MDA-MB-231, which revealed the appearance of apoptosis characteristics like shrinkage of the cells and blebbing of the cell membrane. In addition, the flow cytometric analysis showed that the MDA-MB-231 cells stained with Annexin V/PI had a rise in the count of the cells in the early and late apoptosis stages. Moreover, gel electrophoresis detected DNA fragmentation in the ferulic acid-treated cells. Finally, the effect of the compound was tested at the molecular level by qRT-PCR. An upregulation of the pro-apoptotic genes (BAX and P53) and a downregulation of the anti-apoptotic gene (BCL-2) were observed. Consequently, our study demonstrated that these isolated compounds, especially ferulic acid, may be vital anticancer agents, particularly for breast cancer, through its induction of apoptosis through the P53-dependent pathway.

Antidiabetic and Antigout Properties of the Ultrasound-Assisted Extraction of Total Biflavonoids from Selaginella doederleinii Revealed by In Vitro and In Silico Studies

In this study, the extraction, purification and metabolic enzyme inhibition potential of Selaginella doederleinii were investigated. In order to extract the total biflavonoids from S. doederleinii (SDTBs), the optimum extraction process was obtained by optimizing the ultrasonic extraction parameters using response-surface methodology. This resulted in a total biflavonoid content of 22.26 ± 0.35 mg/g. Purification of the S. doederleinii extract was carried out using octadecylsilane (ODS), and the transfer rate of the SDTBs was 82.12 ± 3.48% under the optimum purification conditions. We determined the effect of the SDTBs on α-glucosidase (AG), α-amylase and xanthine oxidase (XOD) and found that the SDTBs had an extremely potent inhibitory effect on AG, with an IC50 value of 57.46 μg/mL, which was much lower than that of the positive control. Meanwhile, they also showed significant inhibition of XOD and α-amylase, with IC50 values of 289.67 μg/mL and 50.85 μg/mL, respectively. In addition, molecular docking studies were carried out to understand the nature of the action of the biflavonoids on AG and XOD. The results showed that robustaflavone had the lowest binding energy to AG (-11.33 kcal/mol) and XOD (-10.21 kcal/mol), while, on the other hand, amentoflavone showed a good binding affinity to AG (-10.40 kcal/mol) and XOD (-9.962 kcal/mol). Moreover, molecular dynamics simulations verified the above results.

Pachira aquatica: biological activity and chemical composition of leaves, flowers, and seeds

The chemical composition of Pachira aquatica crude extracts flowers, leaves, and seeds was obtained by UHPLC-ESI/qTOF and GC/MS. The antiproliferative activity was evaluated against the human tumour cell lines AGS (gastric), CaCo-2 (colorectal), MCF-7 (breast), and NCI-H460 (lung). The anti-inflammatory and cellular antioxidant activities were also studied. Flavonoids, phenolic acids, coumarins, and saturated fatty acids were identified in the samples. The concentration of extracts responsible for inhibiting 50% of nitric oxide production ranged from (149 to > 400 µg mL-1). Antiproliferative activity against the tumour cell lines was: AGS (GI50 175 to > 400 µg mL-1), Caco-2 (GI50 215 to > 400 µg mL-1), MCF7 (GI50 232 to > 400 µg mL-1) and NCI-H460 (GI50 208 to > 400 µg mL-1). Cellular antioxidant activity remained between 73% to > 2000%. The selectivity index (SI) ranged from 1.00 to 2.78, indicating low antiproliferative activity.

Sustainable control of Microcystis aeruginosa, a harmful cyanobacterium, using Selaginella tamariscina extracts

Eco-friendly reagents derived from plants represent a promising strategy to mitigate the occurrence of toxic cyanobacterial blooms. The use of an amentoflavone-containing Selaginella tamariscina extract (STE) markedly decreased the number of Microcystis aeruginosa cells, thus demonstrating significant anti-cyanobacterial activity. In particular, the Microcystis-killing fraction obtained from pulverized S. tamariscina using hot-water-based extraction at temperatures of 40 °C induced cell disruption in both axenic and xenic M. aeruginosa. Liquid chromatographic analysis was also conducted to measure the concentration of amentoflavone in the STE, thus supporting the potential M. aeruginosa-specific killing effects of STE. Bacterial community analysis revealed that STE treatment led to a reduction in the relative abundance of Microcystis species while also increasing the 16S rRNA gene copy number in both xenic M. aeruginosa NIBR18 and cyanobacterial bloom samples isolated from a freshwater environment. Subsequent testing on bacteria, cyanobacteria, and algae isolated from freshwater revealed that STE was not toxic for other taxa. Furthermore, ecotoxicology assessment involving Aliivibrio fischeri, Daphnia magna, and Danio rerio found that high STE doses immobilized D. magna but did not impact the other organisms, while there was no change in the water quality. Overall, due to its effective Microcystis-killing capability and low ecotoxicity, aqueous STE represents a promising practical alternative for the management of Microcystis blooms.

An efficient method for the preparative isolation and purification of alkaloids from Gelsemium by using high speed counter-current chromatography and preparative HPLC

We established an efficient method using high-speed countercurrent chromatography (HSCCC) combined with preparative high-performance liquid chromatography (prep-HPLC) for isolating and purifying Gelsemium elegans (G. elegans) alkaloids. First, the two-phase solvent system composed of 1% triethylamine aqueous solution/n-hexane/ethyl acetate/ethanol (volume ratio 4:2:3:2) was employed to separate the crude extract (350 mg) using HSCCC. Subsequently, the mixture that resulted from HSCCC was further separated by Prep-HPLC, resulting in seven pure compounds including: 14-hydroxygelsenicine (1, 12.1 mg), sempervirine (2, 20.8 mg), 19-(R)-hydroxydihydrogelelsevirine (3, 10.1 mg), koumine (4, 50.5 mg), gelsemine (5, 32.2 mg), gelselvirine (6, 50.5 mg), and 11-hydroxyhumanmantenine (7, 12.5 mg). The purity of these seven compounds were 97.4, 98.9, 98.5, 99, 99.5, 96.8, and 85.5%, as determined by HPLC. The chemical structures of the seven compounds were analyzed and confirmed by electrospray ionization mass spectrometry (ESI-MS), 1H-nuclear magnetic resonance (1H NMR), and 13 C-nuclear magnetic resonance (13 C NMR) spectra. The results indicate that the HSCCC-prep-HPLC method can effectively separate the major alkaloids from the purified G. elegans, holding promising prospects for potential applications in the separation and identification of other traditional Chinese medicines.

Anti-tumor effect and mechanism of the total biflavonoid extract from S doederleinii on human cervical cancer cells in vitro and in vivo

In this study, the therapeutic effect and possible mechanism of the total biflavonoid extract of Selaginella doederleinii Hieron (SDTBE) against cervical cancer were originally investigated in vitro and in vivo. First, the inhibition of SDTBE on proliferation of cervical cancer HeLa cells was evaluated, followed by morphological observation with AO/EB staining, Annexin V/PI assay, and autophagic flux monitoring to evaluate the possible effect of SDTBE on cell apoptosis and autophagy. Cell cycle, as well as mitochondrial membrane potential (ΔѰm), was detected with flow cytometry. Further, the apoptosis related protein expression and the autophagy related gene LC3 mRNA transcription level were analyzed by Western blot (WB) and real-time quantitative polymerase chain reaction (RT-qPCR), respectively. Finally, the anti-cervical cancer effect of the SDTBE was also validated in vivo in HeLa cells grafts mice. As results, SDTBE inhibited HeLa cells proliferation with the IC50 values of 49.05 ± 6.76 and 44.14 ± 4.75 μg/mL for 48 and 72 h treatment, respectively. The extract caused mitochondrial ΔѰ loss, induced cell apoptosis by upregulating Bax, downregulating Bcl-2, activating Caspase-9 and Caspase-3, promoting cell autophagy and blocking the cell cycle in G0/G1 phase. Furthermore, 100, 200, and 300 mg/kg SDTBE suppressed the growth of HeLa cells xenografts in mice with the mean inhibition rates, 25.3 %, 57.5 % and 62.9 %, respectively, and the change of apoptosis related proteins and microvascular density was confirmed in xenografts by immunohistochemistry analysis. The results show that SDTBE possesses anti-cervical cancer effect, and the mechanism involves in activating Caspase-dependent mitochondrial apoptosis pathway.

A systematic review on antimicrobial activities of green synthesised Selaginella silver nanoparticles

BACKGROUND

Metallic nanoparticles from different natural sources exhibit superior therapeutic options as compared to the conventional methods. Selaginella species have attracted special attention of researchers worldwide due to the presence of bioactive molecules such as flavonoids, biflavonoids, triterpenes, steroids, saponins, tannins and other secondary metabolites that exhibit antimicrobial, antiplasmodial, anticancer and anti-inflammatory activities. Environment friendly green synthesised silver nanoparticles from Selaginella species provide viable, safe and efficient treatment against different fungal pathogens.

OBJECTIVE

This systematic review aims to summarise the literature pertaining to superior antifungal ability of green synthesised silver nanoparticles using plant extracts of Selaginella spp. in comparison to both aqueous and ethanolic raw plant extracts by electronically collecting articles from databases.

METHODS

The recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis were taken into consideration while preparing this review. The titles and abstracts of the collected data were stored in Endnote20 based on the inclusion and exclusion criteria. The search strategy included literature from established sources like PubMed, Google Scholar and Retrieval System Online using subject descriptors.

RESULTS

The search yielded 60 articles with unique hits. After removal of duplications, 46 articles were identified, 40 were assessed and only seven articles were chosen and included in this review based on our eligibility criteria.

CONCLUSION

The physicochemical and preliminary phytochemical investigations of Selaginella suggest higher drug potency of nanoparticles synthesised from plant extract against different diseases as compared to aqueous and ethanolic plant extracts. The study holds great promise as the synthesis of nanoparticles involves low energy consumption, minimal technology and least toxic effects.

Study on Anti-Inflammatory Mechanism of Angelica pubescens Based on Network Pharmacology and Molecular Docking

References and data show that AP has a certain effect on alleviating inflammation. Based on the methods of network pharmacology and molecular docking, this paper predicts the potential mechanism of anti-inflammatory effect of the effective components. Methods: Active components and target genes of AP were screened out by SymMap, an associated database of TCM syndromes. First, screen out the active components according to the setting conditions, and its molecular structure file was obtained from the PubChem database. The target genes of anti-inflammatory effect were obtained from GeneCards database with “anti-inflammation effect” as the keyword, and then the common gene targets between AP and anti-inflammatory effect were screened. The PPI network diagram was constructed with Cytoscape 3.80 software to screen the core genes. The GO function and KEGG pathway of the core genes were enriched and analyzed by David database; 3D view of proteins encoded by the core gene from the PDB database, conduct molecular docking between the active components and the core proteins in Auto Dock Vina software, and made a heat map with binding free energy. Results: The main anti-inflammatory components were O-Acetylcolumbianetin, isoindigo, Nodakenetin, Marmesin, Diphencyprone; The core targets are TNF, VEGFA, IL6, TP53, IL1B, ESR1, MMP9, PPARG, Jun, CASP3, PTGS2. AP participated in cytokine-mediated signaling pathway, response to drug, positive regulation of gene expression, and other processes by regulating the combination of extracellular space, cell surface with protein and enzyme, and then exert anti-inflammatory activity. The signal pathways mainly involved IL-17 signaling pathway, hepatitis B, TNF signaling pathway, inflammatory bowel disease, rheumatoid arthritis, etc.; Through molecular docking, it was found that the key targets were MMP9, TNF, PTGS2, ESR1, JUN, and PPARG, while the active components which ha,d a strong effect on these genes were O-Acetylcolumbianetin, isoindigo, Nodakenetin, Marmesin, Diphencyprone. Conclusion: This study used network pharmacology and molecular docking methods to predict the potential active components, target genes, and signal pathways of the anti-inflammatory effect of AP, so as to provide a theoretical reference for the follow-up experimental research and clinical treatment of AP.

Inhibitory effect of Selaginella doederleinii hieron on human cytochrome P450

Introduction: Selaginella doederleinii Hieron is a traditional Chinese herbal medicine, the ethyl acetate extract from Selaginella doederleinii (SDEA) showed favorable anticancer potentials. However, the effect of SDEA on human cytochrome P450 enzymes (CYP450) remains unclear. To predict the herb-drug interaction (HDI) and lay the groundwork for further clinical trials, the inhibitory effect of SDEA and its four constituents (Amentoflavone, Palmatine, Apigenin, Delicaflavone) on seven CYP450 isoforms were investigated by using the established CYP450 cocktail assay based on LC-MS/MS. Methods: Appropriate substrates for seven tested CYP450 isoforms were selected to establish a reliable cocktail CYP450 assay based on LC-MS/MS. The contents of four constituents (Amentoflavone, Palmatine, Apigenin, Delicaflavone) in SDEA were determined as well. Then, the validated CYP450 cocktail assay was applied to test the inhibitory potential of SDEA and four constituents on CYP450 isoforms. Results: SDEA showed strong inhibitory effect on CYP2C9 and CYP2C8 (IC₅₀ ≈ 1 μg/ml), moderate inhibitory effect against CYP2C19, CYP2E1 and CYP3A (IC₅₀ < 10 μg/ml). Among the four constituents, Amentoflavone had the highest content in the extract (13.65%) and strongest inhibitory effect (IC₅₀ < 5 μM), especially for CYP2C9, CYP2C8 and CYP3A. Amentoflavone also showed time-dependent inhibition on CYP2C19 and CYP2D6. Apigenin and Palmatine both showed concentration-dependent inhibition. Apigenin inhibited CYP1A2, CYP2C8, CYP2C9, CYP2E1 and CYP3A. Palmatine inhibited CYP3A and had a weak inhibitory effect on CYP2E1. As for Delicaflavone, which has the potential to develop as an anti-cancer agent, showed no obvious inhibitory effect on CYP450 enzymes. Conclusion: Amentoflavone may be one of the main reasons for the inhibition of SDEA on CYP450 enzymes, the potential HDI should be considered when SDEA or Amentoflavone were used with other clinical drugs. On the contrast, Delicaflavone is more suitable to develop as a drug for clinical use, considering the low level of CYP450 metabolic inhibition.

Delicaflavone reactivates anti-tumor immune responses by abrogating monocytic myeloid cell-mediated immunosuppression

BACKGROUND

Myeloid cell-mediated immunosuppression is a major obstacle to checkpoint blockade immunotherapy. We previously reported that total biflavonoids extract from Selaginella doederleinii (TBESD) and a flavone monomer isolated from TBESD, named Delicaflavone, have favorable anti-tumor activity. However, whether TBESD and Delicaflavone could affect the tumor microenvironment (TME) remains unclear.

PURPOSE

In this study, we focused on the TME to determine whether TBESD and Delicaflavone could restore anti-tumor immune response.

METHODS

4T1 tumor-bearing immunocompetent BALB/c mice and T cell-deficient nude mice were used to examine the effect of TBESD on T cell-mediated immunity in vivo. Multi-parameter flow cytometry was conducted to evaluate the impacts of TBESD on TME. Primary cells, including murine CD8⁺ T cells, tumor associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs) were prepared to investigate the modulatory activities of TBESD on immune cells. It was further determined whether Delicaflavone or Amentoflavone, two typical functional biflavones from TBESD, mediated those effects of TBESD. Finally, the impacts of TBESD and Delicaflavone on Jak1/STAT6 signaling pathway were explored via western blot.

RESULTS

We found that TBESD significantly reduced 4T1 tumor growth in immunocompetent BALB/c mice, but not in nude mice. This effect was associated with the regulation of TME, shown as an increase in functional T cells and M1 phenotype TAMs (M1-TAMs), and a decrease in M2 phenotype TAMs (M2-TAMs), monocytic-MDSCs (M-MDSCs) and regulatory T cells (Tregs) in TBESD-treated BALB/c mouse 4T1 tumors. It was found ex vivo that TBESD restrained the viability and immunosuppressive properties of M2-TAMs and M-MDSCs, especially for the loss of arginase-1 expression. Additionally, TBESD re-educated M2-TAMs to an M1 like phenotype. Further investigations determined that Delicaflavone predominantly mediated the immuno-modulatory activities of TBESD both ex vivo and in vivo. Finally, Delicaflavone and TBESD blocked Jak1/STAT6 signaling pathway in M2-TAMs and MDSCs.

CONCLUSION

The present study suggests Delicaflavone as a potent natural inhibitor of M2-TAMs and MDSCs, which fills the gap in knowledge on the immuno-modulatory effects of TBESD and Delicaflavone, and could have translational implications to improve the efficacy of cancer immunotherapy.

Siamenflavones A-C, three undescribed biflavonoids from Selaginella siamensis Hieron. and biflavonoids from spike mosses as EGFR inhibitor

Three undescribed biflavonoids (BFVs), siamenflavones A-C along with twelve BFVs were isolated from Selaginella siamensis Hieron. and Selaginella bryopteris (L.) Baker (Selaginellaceae). The chemical structures of undescribed compounds were established through comprehensive spectroscopic techniques, chemical correlations, and X-ray crystallography. The ten isolated BFVs, siamenflavones A-C, delicaflavone, chrysocauflavone, robustaflavone, robustaflavone-4-methylether, amentoflavone, tetrahydro-amentoflavone, and sciadopitysin were evaluated for the antiproliferative effects against four human cancer cell lines A549, H1975, HepG2 and T47D. Delicaflavone and robustaflavone 4'-methylether exerted strong effects on the four human cancer cell lines. Siamenflavone B, delicaflavone and robustaflavone 4'-methylether showed potent inhibitory activities against wild-type EGFR. The inhibition of the compounds was further supported by molecular docking and predictive intermolecular interactions. Molecular dynamics simulation studies of siamenflavone B and robustaflavone-4'-methylether complexed to EGFR-TK further supported inhibition of the compounds to the ATP binding site. Finally, analysis of pharmacokinetic and electronic properties using density-functional theory and known drug index calculations suggest that the compounds are pharmaceutically compatible for drug administration.

Cytotoxic Biflavonoids from Selaginella braunii

A new biflavonoid, (2″ S)-8″-C-methyl-2″,3″-dihydrorobustaflavone-4′-methyl ether (1) and 5 known robustaflavones (2-6) were isolated from the 70% EtOH extract of Selaginella braunii for the first time. The structures of 1 and the known compounds were identified by performing a comprehensive analysis of spectroscopic data including ultraviolet-visible, high-resolution electrospray ionization mass spectrometry, 1-dimensional and 2-dimensional nuclear magnetic resonance, and circular dichroism spectra. Compounds 1-6 were determined for cytotoxic activity against 3 human cancer cell lines (SMMC-7721, MCF-7, and A549). Compound 1 exerted apparent antiproliferative effects on SMMC-7721, MCF-7, and A549 cells, with IC50 values of 18.6, 16.7, and 25.5 μM, respectively.

Flavonoids from Selaginella doederleinii Hieron and Their Antioxidant and Antiproliferative Activities

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.

Disclosing targets and pharmacological mechanisms of total bioflavonoids extracted from Selaginella doederleinii against non-small cell lung cancer by combination of network pharmacology and proteomics

ETHNOPHARMACOLOGICAL RELEVANCE

Previously, the total bioflavonoids extract from Selaginella doederleinii (SDTBE) presented favorable in vitro and in vivo activities against non-small cell lung cancer (NSCLC), hinting at its medicinal potential. However, up to nowadays, targets and integrative action mechanisms of SDTBE are still not very clear, which presents an obstacle to the development of herbal medicine.

AIM OF THE STUDY

The present study aimed to disclose the potential targets and integrative action mechanism of SDTBE against NSCLC.

MATERIALS AND METHODS

A system pharmacology-based strategy including target fishing, network pharmacology analysis and molecular docking were applied to predict the potential targets and pathways for the seven main active ingredients in SDTBE. A proteomics study was subsequently performed for validating the affected pathways and possible targets. Western blot assay, mouse xenograft tumor model and immunofluorescence assays were used to further confirm the key targets and integrative action mechanisms of SDTBE against NSCLC.

RESULTS

By system pharmacology, it was inferred that SDTBE could mainly act on mitogen-activated protein kinase (MAPK) and PI3K-AKT signaling pathways by targeting epidermal growth factor receptor (EGFR), protein kinase B (AKT) and mitogen-activated or extracellular signal-regulated protein kinase (MEK), which was validated by proteomics results, and further confirmed in vitro and in vivo by Western blot and immunofluorescence assays.

CONCLUSION

SDTBE targeting multi-targets including EGFR, AKT and MEK could exert its anti-NSCLC effect mainly via MAPK and PI3K-AKT signaling pathways.

Synthesis, biological evaluation, pharmacokinetic studies and molecular docking of 4'''-acetyl-delicaflavone as antitumor agents

Structural modification of natural products is the effective option to improve their pharmacological effects and drug properties. DLF is a lead compound of antitumor drug, which is a broad-spectrum, low toxic and high-efficient component isolated from Selaginella doederleinii Hieron by our research group. Here, we report the structural modification method of this component, and find that the acetylated product of C4'''- OH (C4'''-acetyl-delicaflavone, 4'''ADLF) has better inhibitory effect on the selected cancer cell lines, including, lung, liver, colon and cervical cancer cell lines. Since the increased water solubility of 4'''ADLF may lead to higher absorption rate and activity, we evaluate the pharmacodynamics in vitro and in vivo, and the pharmacokinetic of 4'''ADLF. It shows that 4'''ADLF inhibit the proliferation and induce cycle arrest in tumor cells, and had better anticancer activity and bioavailability than DLF.

Tea and coffee polyphenols and their biological properties based on the latest in vitro investigations

Tea and coffee contain numerous polyphenolic compounds that exhibit health-promoting properties for humans, including antioxidant and neuroprotective properties, and can also take part in the treatment of covid-19 and improve fertility. This review, presents the activity of polyphenols found in different types of tea and coffee and describes the effects of tea fermentation and coffee roasting on their polyphenol composition and antioxidant properties. Polyphenol oxidase activity is reduced in the fermentation process; therefore black tea contains significantly less polyphenolic compounds compared to green and white tea. Epigallocatechin-3-gallate - a polyphenol from tea - effectively has been shown to inhibit the activity of SARS-CoV-2 as it blocked binding of coronavirus 2 to human angiotensin converting enzyme 2, decreased the expression of inflammatory factors in the blood, including tumor necrosis factor-α and interleukin-6, and significantly increased the overall fertilization efficiency in animals. Coffee roasting process influences both the content of polyphenols and the oxidative activity. The lowest levels of active compounds such as caffeine, chlorogenic acid and coffee acids are identified in roasted coffee beans. On the other hand, light coffee and green coffee show the strongest cytotoxic potential and antioxidant properties, and thus the greatest ability to decrease apoptosis by stopping the cell cycle in the S phase. Proteins, such as components of milk, can strongly bind/interact with phenolic compounds (especially, the CGAs) contain in coffee, which may explain the negative influence of milk on its antioxidant properties. Coffee polyphenols have also antiproliferative and antiesterase activities, which may be important in prevention of cancer and neurodegenerative disorders, respectively. In this review, biological properties of tea and coffee polyphenols, observed mainly in in vitro studies have been described. Based on these findings, future directions of the research works on these compounds have been suggested.

Biflavonoids from Selaginella doederleinii as Potential Antitumor Agents for Intervention of Non-Small Cell Lung Cancer

Four new biflavonoids (1-4) were isolated from Selaginella doederleinii together with a known biflavonoid derivative (5). Their structures contained a rare linker of individual flavones to each other by direct C-3-O-C-4''' bonds, and were elucidated by extensive spectroscopic data, including HRESIMS, NMR and ECD data. All isolates significantly inhibited the proliferation of NSCLC cells (IC50 = 2.3-8.4 μM) with low toxicity to non-cancer MRC-5 cells, superior to the clinically used drug DDP. Furthermore, the most active compound 3 suppressed XIAP and survivin expression, promoted upregulation of caspase-3/cleaved-caspase-3, as well as induced cell apoptosis and cycle arrest in A549 cells. Together, our findings suggest that 3 may be worth studying further for intervention of NSCLC.

Bioactivity of natural biflavonoids in metabolism-related disease and cancer therapies

Natural biflavonoids, such as amentoflavone, bilobetin, ginkgetin, isoginkgetin, taiwaniaflavone, morelloflavone, delicaflavone, hinokiflavone, and other derivatives (~ 40 biflavonoids), are isolated from Selaginella sp., Ginkgo biloba, Garcinia sp., and several other species of plants. They are able to exert therapeutic benefits by regulating several proteins/enzymes (PPAR-γ, CCAAT/enhancer-binding protein α [C/EBPα], STAT5, pancreatic lipase, PTP1B, fatty acid synthase, α-glucosidase [AG]) and insulin signaling pathways (via PI3K-AKT), which are linked to metabolism, cell growth, and cell survival mechanisms. Deregulated insulin signaling can cause complications of obesity and diabetes, which can lead to cognitive disorders such as Alzheimer's, Parkinson's, and dementia; therefore, the therapeutic benefits of these biflavones in these areas are highlighted. Since biflavonoids have shown potential to regulate metabolism, growth- and survival-related protein/enzymes, their relation to tumor growth and metastasis of cancer associated with angiogenesis are highlighted. The translational role of biflavones in cancer with respect to the inhibition of metabolism-related processes/pathways, enzymes, or proteins, such as STAT3/SHP-1/PTEN, kinesins, tissue kallikreins, aromatase, estrogen, protein modifiers, antioxidant, autophagy, and apoptosis induction mechanisms, are discussed. Finally, considering their observed bioactivity potential, oral bioavailability studies of biflavones and related clinical trials are outlined.

Anti-MRSA Constituents from Ruta chalepensis (Rutaceae) Grown in Iraq, and In Silico Studies on Two of Most Active Compounds, Chalepensin and 6-Hydroxy-rutin 3',7-Dimethyl ether

Ruta chalepensis L. (Rutaceae), a perennial herb with wild and cultivated habitats, is well known for its traditional uses as an anti-inflammatory, analgesic, antipyretic agent, and in the treatment of rheumatism, nerve diseases, neuralgia, dropsy, convulsions and mental disorders. The antimicrobial activities of the crude extracts from the fruits, leaves, stem and roots of R. chalepensis were initially evaluated against two Gram-positive and two Gram-negative bacterial strains and a strain of the fungus Candida albicans. Phytochemical investigation afforded 19 compounds, including alkaloids, coumarins, flavonoid glycosides, a cinnamic acid derivative and a long-chain alkane. These compounds were tested against a panel of methicillin-resistant Staphylococcus aureus (MRSA) strains, i.e., ATCC 25923, SA-1199B, XU212, MRSA-274819 and EMRSA-15. The MIC values of the active compounds, chalepin (9), chalepensin (10), rutamarin (11), rutin 3′-methyl ether (14), rutin 7,4′-dimethyl ether (15), 6-hydroxy-rutin 3′,7-dimethyl ether (16) and arborinine (18) were in the range of 32–128 µg/mL against the tested MRSA strains. Compounds 10 and 16 were the most active compounds from R. chalepensis, and were active against four out of six tested MRSA strains, and in silico studies were performed on these compounds. The anti-MRSA activity of compound 16 was comparable to that of the positive control norfloxacin (MICs 32 vs 16 μg/mL, respectively) against the MRSA strain XU212, which is a Kuwaiti hospital isolate that possesses the TetK tetracycline efflux pump. This is the first report on the anti-MRSA property of compounds isolated from R. chalepensis and relevant in silico studies on the most active compounds.

Molecular mechanism and pharmacokinetics of flavonoids in the treatment of resistant EGF receptor-mutated non-small-cell lung cancer: A narrative review

Here, we review the molecular mechanism and pharmacokinetics of flavonoids in the treatment of resistant EGF receptor (EGFR)-mutated non-small-cell lung cancer (NSCLC) and particularly the possible mechanism(s) of delicaflavone, a biflavonoid extracted from Selaginella doederleinii Hieron. EGFR TK inhibitors (EGFR-TKI) are ubiquitously used in the treatment of NSCLC bearing EGFR mutations. However, patients treated with EGFR-TKI inevitably and continuously develop resistance. In laboratory studies, flavonoids, as potential adjuvants for cancer chemotherapy, exhibited anti-cancer properties such as inhibition of chemoresistance by interference with ABC transporters-induced drug efflux, curbing of c-MET amplification, or reversal of T790M mutation-mediated resistance. The current review aims at summarizing the association between the anti-cancer potentials of flavonoids and their possible regulatory roles in certain types of mutation that could trigger EGFR-TKI resistance in NSCLC. Potential practical applications of these phytochemicals, as well as the relevant pharmacokinetics, are also discussed.

Improved solubility, dissolution rate, and oral bioavailability of main biflavonoids from Selaginella doederleinii extract by amorphous solid dispersion

Amentoflavone, robustaflavone, 2″,3″-dihydro-3′,3‴-biapigenin, 3′,3‴-binaringenin, and delicaflavone are five major hydrophobic components in the total biflavonoids extract from Selaginella doederleinii (TBESD) that display favorable anticancer properties. The purpose of this study was to develop a new oral delivery formulation to improve the solubilities, dissolution rates, and oral bioavailabilities of the main ingredients in TBESD by the solid dispersion technique. Solid dispersions of TBESD with various hydrophilic polymers were prepared, and different technologies were applied to select the suitable carrier and method. TBESD amorphous solid dispersion (TBESD-ASD) with polyvinylpyrrolidone K-30 was successfully prepared by the solvent evaporation method. The physicochemical properties of TBESD-ASD were investigated by scanning electron microscopy, differential scanning calorimetry, and Fourier-transform infrared spectroscopy. As a result, TBESD was found to be molecularly dispersed in the amorphous carrier. The solubilities and dissolution rates of all five ingredients in the TBESD-ASD were significantly increased (nearly 100% release), compared with raw TBESD. Meanwhile, TBESD-ASD showed good preservation stability for 3 months under accelerated conditions of 40 °C and 75% relative humidity. A subsequent pharmacokinetic study in rats revealed that C_max and AUC_0–t of all five components were significantly increased by the solid dispersion preparation. An in vivo study clearly revealed that compared to raw TBESD, a significant reduction in tumor size and microvascular density occurred after oral administration of TBESD-ASD to xenograft-bearing tumor mice. Collectively, the developed TBESD-ASD with the improved solubility, dissolution rates and oral bio-availabilities of the main ingredients could be a promising chemotherapeutic agent for cancer treatment.

Ethyl Acetate Extract of Selaginella doederleinii Hieron Induces Cell Autophagic Death and Apoptosis in Colorectal Cancer via PI3K-Akt-mTOR and AMPKα-Signaling Pathways

Colorectal cancer is one type of cancer with high incidence rate and high mortality worldwide. Thus, developing new chemotherapeutic drugs is important. The Selaginella doederleinii Hieron ethyl acetate (SDEA) extract showed good anti-colon cancer effect in vitro and in vivo, but its mechanism is unclear. This study aimed to further reveal the anti-colon cancer effect of SDEA and its possible mechanism. The effects on cell viability, apoptosis, autophagy, and cell cycle in colorectal cells (HT29 and HCT116) were studied using MTT assay, fluorescence microscopy, transmission electron microscopy, and flow cytometry. The mechanisms were further studied using cell transfection, Western blot, and real-time quantitative polymerase chain reaction assay. The effect of xenotransplantation in vivo was observed using immunohistochemistry. Results showed that SDEA inhibited cell proliferation and induced cell morphological changes, cell cycle arrest, autophagy, and apoptosis. It also induced loss of mitochondrial membrane potential, increased the autophagic flux, raised the ratio of Bax/Bcl-2, activated caspases, and inhibited PI3K-Akt-mTOR signaling pathways. Furthermore, SDEA inhibited the growth of xenograft tumors in a dose-dependent manner. Immunohistochemistry analysis confirmed the alteration of autophagy- and apoptosis-related proteins and immunohistochemical microvascular density in xenografts, which were consistent with the results in vitro. Therefore, SDEA is important for developing candidate drugs against colorectal cancers.

Phytochemical profiling, antioxidant and antibacterial efficacy of a native Himalayan Fern: Woodwardia unigemmata (Makino) Nakai

Present work elucidates the antioxidant and antibacterial activity of Woodwardia unigemmata (Makino) Nakai along with chemical characterization using its aqueous (AEW), methanol (MEW), and hexane (HEW) extracts. Chemical profile of different extracts was illustrated by using Gas chromatography and mass spectrometry (GC-MS) analysis. Antioxidant activities were tested using DPPH and FRAP assays, total phenolic and flavonoid content by Folin-Ciocalteu and aluminum chloride method, respectively. Further, antibacterial activity against six plant and four animal pathogenic bacteria was analyzed by employing the disc diffusion assay. GC-MS analysis revealed the presence of catechol (21.96%), glycerol (20.22%), n-pentadecanoic acid (6.95%), glyceryl monoacetate (6.35 %), ethyl acetimidate (5.39 %) and 3-hydroxy-2,3-dihydromaltol (5.36%) in AEW; β-sitosterol (17.39%), pentadecanoic acid (9.81%), vitamin E (7.82%) and glycerol (7.05%) in MEW; γ-sitosterol (33.45%), vitamin E (10.04%) and campesterol (7.32%) in HEW as major constituents. Maximum phenolics (873 ± 6.01 mgGAE/g dry extract) as well as flavonoids (151 ± 11.44 mgQE/g dry extract) content was found in MEW, which also showed remarkable antioxidant potential (IC₅₀ 6.07 ± 1.4 µg/ml for DPPH and 768 ± 10.4 mg AAE/g dry extract for FRAP assay. In antibacterial activity, maximum inhibition (15 ± 0.9 mm) was observed for HEW against R. solanacearum, followed by AEW against A. tumefaciens and X. phaseoli (11 ± 0.3 mm each). MEW was found positive only against A. tumefaciens. Significant minimum inhibitory concentration (MIC) value observed for AEW against L. monocytogenes (10 mg/ml). Polar extracts had remarkable antioxidant potential, while non-polar extract did show significant antibacterial activity. Further, GC- MS reports indicated that this traditionally useful fern species can be an excellent source of biologically active compounds.

Proliposomes for oral delivery of total biflavonoids extract from Selaginella doederleinii: formulation development, optimization, and in vitro-in vivo characterization

Purpose

Amentoflavone, robustaflavone, 2'',3''-dihydro-3',3'''-biapigenin, 3',3'''-binaringenin and delicaflavone are five major active ingredients in the total biflavonoids extract from Selaginella doederleinii (TBESD) with favorable anticancer properties. However, the natural-derived potent antitumor agent of TBESD is undesirable due to its poor solubility. The present study was to develop and optimize a proliposomal formulation of TBESD (P-TBESD) to improve its solubility, oral bioavailability and efficacy.

Materials and methods

P-TBESD containing a bile salt, a protective hydrophilic isomalto-oligosaccharides (IMOs) coating, were successfully prepared by thin film dispersion-sonication method. The physicochemical and pharmacokinetic properties of P-TBESD were characterized, and the antitumor effect was evaluated using the HT-29 xenograft-bearing mice models in rats.

Results

Compared with TBESD, the relative bioavailability of amentoflavone, robustaflavone, 2'',3''-dihydro-3',3'''-biapigenin, 3',3'''-binaringenin and delicaflavone from P-TBESD were 669%, 523%, 761%, 955% and 191%, respectively. The results of pharmacodynamics demonstrated that both TBESD and P-TBESD groups afforded antitumor effect without systemic toxicity, and the antitumor effect of P-TBESD was significantly superior to that of raw TBESD, based on the tumor growth inhibition and histopathological examination.

Conclusion

Hence, IMOs-modified proliposomes have promising potential for TBESD solving the problem of its poor solubility and oral bioavailability, which can serve as a practical oral preparation for TBESD in the future cancer therapy.

New cytotoxic biflavones from Selaginella doederleinii

Three new biflavones, apigenin-(3',8″)-chrysin (1), (2S)-2,3-Dihydroametoflavone 5,4'-dimethyl ether (2), and (2S)-5″,7″-Dihydroxy-2″-phenoxychromonyl-(4'″,3')-naringenin (3), together with seven known biflavones (4-10) were isolated from the 75% EtOH extract of Selaginella doederleinii. The structures of new compounds were established by application of spectroscopic methods, including 1D and 2D NMR, HRMS, and CD measurements. In addition, all new compounds were evaluated for their cytotoxic potential against three human cancer cell lines A549, MCF-7, and SMMC-7721 in vitro. Compound 2 exhibited potent cytotoxic activity with IC₅₀ values ranging from 6.35 to 10.18 μM.

A new byciclic monoterpene glucoside and a new biflavone from the male reproduction organs of Wollemia nobilis

In this work, the fifth part of an ongoing phytochemical study on Wollemia nobilis was reported. The attention was now focused on the male reproduction organs of which the content in both primary and secondary metabolites was analyzed. Twenty compounds, belonging to seven different classes of natural compounds, were identified from the ethanolic extract by means of Column Chromatography and NMR and MS Spectroscopy. They all represent new compounds for the studied organ whereas some of them are also new constituents of the genus or even previously undescribed phytochemicals. Their presence was able to display a general overview of these organs from the phytochemical standpoint and to provide more elements in confirmation with the current botanical classification of the species. Moreover, they add a further experimental evidence of the tendency of this species to accumulate different metabolites in different organs. This characteristic as well as the occurrence of several compounds with added value, make this plant a possible candidate for large scale cultivation with extractive purposes to obtain useful phytochemicals for botanicals and pharmaceutical fields. Moreover, they offer the opportunity to develop an additional method of conservation and protection for this endangered and very rare species.

Rapid characterization of nonpolar or low-polarity solvent extracts from herbal medicines by solvent-assisted electrospray ionization mass spectrometry

RATIONALE

The direct detection of nonpolar and low-polarity solvent extracts of herbal medicine is difficult by conventional electrospray ionization mass spectrometry (ESI-MS). This problem can be solved by solvent-assisted electrospray ionization mass spectrometry (SAESI-MS). With the help of assisted solvents (ESI-friendly solvents) at the tip of the spray needle, compounds (especially the low-polarity compounds) in nonpolar and low-polarity solvent extracts can be ionized directly.

METHODS

Herbal medicines were ultrasonically extracted with nonpolar or low-polarity solvents, such as petroleum ether. Thereafter, the extracts were analyzed by conventional ESI-MS, atmospheric pressure chemical ionization mass spectrometry (APCI-MS) and SAESI-MS. The mass spectra obtained from these three methods were compared and analyzed.

RESULTS

Unstable ion signals, and even no ion signals, were observed when the nonpolar and low-polarity solvent extracts were detected directly by conventional ESI-MS. Better specificity, higher sensitivity or cleaner spectra were acquired from SAESI-MS by comparing with the performance of conventional ESI-MS. The ion signals generated by SAESI-MS and APCI-MS were observed in clearly different m/z ranges. A variety of potential compounds were detected in the petroleum ether extracts of Pogostemon cablin and Ligusticum chuanxiong. The relative abundances and signal intensities of the same ion signals from the stems, leaves and decoction pieces of Pogostemon cablin were significantly different by SAESI-MS.

CONCLUSIONS

As a convenient and efficient method, SAESI-MS can be used to directly detect compounds (especially the low-polarity compounds) in nonpolar or low-polarity solvent extracts of herbal medicines, providing abundant chemical information for pharmacological studies. SAESI-MS allows the simultaneous qualitative analysis of multiple compounds in the same complex samples and is thus particularly suitable for the preliminary screening of compounds in complex samples. SAESI-MS can be used to differentiate the different parts of herbal medicines.

A review of the use of pteridophytes for treating human ailments

The aim of this review was to explore the pharmacological activity of early tracheophytes (pteridophytes) as an alternative medicine for treating human ailments. As the first vascular plants, pteridophytes (aka, ferns and fern allies) are an ancient lineage, and human beings have been exploring and using taxa from this lineage for over 2000 years because of their beneficial properties. We have documented the medicinal uses of pteridophytes belonging to thirty different families. The lycophyte Selaginella sp. was shown in earlier studies to have multiple pharmacological activity, such as antioxidant, anti-inflammatory, anti-cancer, antidiabetic, antiviral, antimicrobial, and anti-Alzheimer properties. Among all the pteridophytes examined, taxa from the Pteridaceae, Polypodiaceae, and Adiantaceae exhibited significant medicinal activity. Based on our review, many pteridophytes have properties that could be used in alternative medicine for treatment of various human illnesses. Biotechnological tools can be used to preserve and even improve their bioactive molecules for the preparation of medicines against illness. Even though several studies have reported medicinal uses of ferns, the possible bioactive compounds of several pteridophytes have not been identified. Furthermore, their optimal dosage level and treatment strategies still need to be determined. Finally, the future direction of pteridophyte research is discussed.

Simultaneous quantification of five biflavonoids in rat plasma by LC-ESI-MS/MS and its application to a comparatively pharmacokinetic study of Selaginella doederleinii Hieron extract in rats

Selaginella doederleinii Hieron is a widely used as folk Chinese medicine for treatment of different cancers. Our previous investigations have confirmed that the total biflavonoids in ethyl acetate extract from S. doederleinii (SDEA) have favorable anticancer potentials. However, the in vivo process of its bioactive ingredients remains unknown. In this paper, a sensitive and reliable method was developed for simultaneous quantification of main five biflavonoids, including amentoflavone, robustaflavone, 2″,3″-dihydro-3',3″-biapigenin, 3',3″-binaringenin and delicaflavone in the ethyl acetate extract of S. doederleinii (SDEA extract) in rat plasma by high-performance liquid chromatography with electrospray ionization-mass spectrometry (HPLC-ESI-MS/MS). Chromatographic separation was performed using an Ultimate^® XB-C18 (100×2.1mm, 3.5μm) with gradient elution of water (0.5% acetic acid) and acetonitrile at 0.2mL/min. All analytes with internal standard (chrysin) were detected using selective reaction monitoring (SRM) in negative ionization mode. The method showed a good linearity over a wide concentration range (r²>0.99). The limits of quantification for the biflavonoids were less than 10ng/mL. The developed method was applied to the comparatively pharmacokinetic study of the five biflavonoids after oral or intravenous administration of SDEA extract in rats. In addition, in silico assessments of permeability and solubility of these biflavonoids were also performed to understand their poor bioavailability. It is the first time to report the in vivo process profiles of the biflavonoids of SDEA extract in rats.

Biological activities of plant extracts from Ficus elastica and Selaginella vogelli: An antimalarial, antitrypanosomal and cytotoxity evaluation

The cytotoxic, antiplasmodial, and antitrypanosomal activities of two medicinal plants traditionally used in Cameroon were evaluated. Wood of Ficus elastica Roxb. ex Hornem. aerial roots (Moraceae) and Selaginella vogelii Spring (Selaginellaceae) leaves were collected from two different sites in Cameroon. In vitro cell-growth inhibition activities were assessed on methanol extract of plant materials against Plasmodium falciparum strain 3D7 and Trypanosoma brucei brucei, as well as against HeLa human cervical carcinoma cells. Criteria for activity were an IC₅₀ value < 10 μg/mL. The extract of S. vogelii did not significantly reduce the viability of P. falciparum at a concentration of 25 μg/mL but dramatically affected the trypanosome growth with an IC₅₀ of 2.4 μg/mL. In contrast, at the same concentration, the extract of F. elastica exhibited plasmodiacidal activity (IC₅₀ value of 9.5 μg/mL) and trypanocidal (IC₅₀ value of 0.9 μg/mL) activity. Both extracts presented low cytotoxic effects on HeLa cancer cell line. These results indicate that the selected medicinal plants could be further investigated for identifying compounds that may be responsible for the observed activities and that may represent new leads in parasitical drug discovery.

Effects of Chinese Medicine as Adjunct Medication for Adjuvant Chemotherapy Treatments of Non-Small Cell Lung Cancer Patients

The aim was to evaluate the effects of traditional Chinese medicine (TCM) as a combination medication with adjuvant chemotherapy on postoperative early stage non-small cell lung cancer (NSCLC) patients. The 314 patients with completely resected stage IB, II or IIIA cancers were assigned into vinorelbine plus cisplatin/carboplatin (NP/NC) (control, n = 158) and NP/NC with additional TCM (intervention, n = 156) groups. The primary endpoint was QOL scores; secondary endpoints were the toxicity and safety of the regimens. The NP/NC regimen caused mild (grade 1 or 2) non-hematologic toxic effects in the patients comprising vomiting (43.6%), fatigue (36.9%), pain (23%), dry mouth (27.6%) and diarrhea (7.9%). The incidence of adverse events was significantly lower in the intervention group than in the control group (0.57% vs 4.02%, P = 0.037). Transient severe (grade 3 or 4) hematological toxic effects occurred less often (hemoglobin reduction (11.9 vs 22.5 percent) and total bilirubin increased (to 42.1 vs 46.2%) in the intervention compared to the control group during the 2nd chemotherapy cycle. When combined with adjuvant chemotherapy, TCM led to partial relief of symptoms in addition to a reduction of side-effects and adverse events caused by the NP/NC regimens.

Analysis of the Total Biflavonoids Extract from Selaginella doederleinii by HPLC-QTOF-MS and Its In Vitro and In Vivo Anticancer Effects

Selaginella doederleinii Hieron has been traditionally used as a folk antitumor herbal medicine in China. In this paper, the phytochemical components of the total biflavonoids extract from S. doederleinii were studied by using high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (HPLC-ESI-QTOF MS/MS) in negative ion mode, and their in vitro and in vivo anticancer effects were evaluated. Four types of biflavonoids from S. doederleinii, including IC3′–IIC8′′, IC3′–IIC6′′, IC3′–IIC3′′′, and C–O linked biflavonoids were examined originally using QTOF MS/MS. The fragmentation behavior of IC3′–IIC3′′′ linked biflavonoids was reported for the first time. A total of twenty biflavonoids were identified or tentatively characterized and eight biflavonoids were found from S. doederleinii for the first time. Furthermore, the 3-(4,5-Dimethyl-2-thizolyl)-2,5-diphenyltertazolium bromide (MTT) assay and xenograft model of mouse lewis lung cancer(LLC) in male C57BL/6 mice revealed favorable anticancer properties of the total biflavonoids extracts from S. doederleinii. The results of this work could provide useful knowledge for the identification of biflavonoids in herbal samples and further insights into the chemopreventive function of this plant.

A Review on the Phytochemistry, Pharmacology, and Pharmacokinetics of Amentoflavone, a Naturally-Occurring Biflavonoid

Amentoflavone (C30H18O10) is a well-known biflavonoid occurring in many natural plants. This polyphenolic compound has been discovered to have some important bioactivities, including anti-inflammation, anti-oxidation, anti-diabetes, and anti-senescence effects on many important reactions in the cardiovascular and central nervous system, etc. Over 120 plants have been found to contain this bioactive component, such as Selaginellaceae, Cupressaceae, Euphorbiaceae, Podocarpaceae, and Calophyllaceae plant families. This review paper aims to profile amentoflavone on its plant sources, natural derivatives, pharmacology, and pharmacokinetics, and to highlight some existing issues and perspectives in the future.

Selagintriflavonoids with BACE1 inhibitory activity from the fern Selaginella doederleinii

Eight triflavonoids, selagintriflavonoids A-H, were isolated from whole herbs of Selaginella doederleinii. The structures of compounds selagintriflavonoids A-C consisted of three naringenin units, whereas those of selagintriflavonoids D-H consisted of apigenin and two naringenin moieties. The structures and absolute configurations of the compounds were determined based on NMR, HRESIMS, and experimental and calculated electronic circular dichroism (ECD) data. The ability of the compounds to inhibit β-secretase (BACE1) was also evaluated. All compounds exhibited BACE1 inhibition with IC₅₀ values ranging from 0.75 to 46.99 μM. Selagintriflavonoid A exhibited the strongest inhibition (0.75 μM) and is thus a promising compound for treating Alzheimer's disease.

Phytochemicals from fern species: potential for medicine applications

Ferns are an important phytogenetic bridge between lower and higher plants. Historically they have been used in many ways by humans, including as ornamental plants, domestic utensils, foods, and in handicrafts. In addition, they have found uses as medicinal herbs. Ferns produce a wide array of secondary metabolites endowed with different bioactivities that could potentially be useful in the treatment of many diseases. However, there is currently relatively little information in the literature on the phytochemicals present in ferns and their pharmacological applications, and the most recent review of the literature on the occurrence, chemotaxonomy and physiological activity of fern secondary metabolites was published over 20 years ago, by Soeder (Bot Rev 51:442-536, 1985). Here, we provide an updated review of this field, covering recent findings concerning the bioactive phytochemicals and pharmacology of fern species.

Development and validation of an LC-MS/MS method for the determination of hinokiflavone in rat plasma and its application to a pharmacokinetic study

Hinokiflavone has drawn a lot of attention for its multiple biological activities. In this study, a sensitive and selective method for determination of hinokiflavone in rat plasma was developed for the first time, using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Amentoflavone was used as an internal standard. Separation was achieved on a Hypersil Gold C₁₈ column with isocratic elution using methanol-water (65:35, v/v) as mobile phase at a flow rate of 0.3 mL/min. A triple quadrupole mass spectrometer operating in the negative electrospray mode with selected reaction monitoring was used to detect the transitions of m/z 537 → 284 for hinokiflavone and m/z 537 → 375 for IS. The LOQ was 0.9 ng/mL with a linear range of 0.9-1000 ng/mL. The intra- and inter-day accuracy (RE%) ranged from -3.75 to 6.91% and from -9.20 to 2.51% and the intra- and inter-day precision (RSD) was between 0.32-14.11 and 2.85-10.04%. The validated assay was successfully applied to a pharmacokinetic study of hinokiflavone in rats. The half-life of drug elimination at the terminal phase was 6.10 ± 1.86 h, and the area under the plasma concentration-time curve from time zero to the time of last measurable concentration and to infinity values obtained were 2394.42 ± 466.86 and 2541.93 ± 529.85 h ng/mL, respectively.

Ethyl acetate extract from Selaginella doederleinii Hieron inhibits the growth of human lung cancer cells A549 via caspase-dependent apoptosis pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Selaginella doederleinii Hieron has been used as a folk medicine for the treatment of different cancers, especially for nasopharyngeal carcinoma, lung cancer and trophoblastic tumor in China. Previously, the ethyl acetate extract from S. doederleinii (SDEA extract) showed favorable anti-cancer potentials. However, the main chemical composition and anticancer mechanism of the SDEA extract were still not very clear. Until now, there are no reports available about the oral toxicity of the extract.

AIM OF STUDY

The present study was to further elucidate the chemical composition and anti-lung cancer mechanism of the SDEA extract, and evaluate the acute oral toxicity of the extract.

MATERIALS AND METHODS

The SDEA extract was separated and analysed by HPLC to disclose its main chemicals. The effects of the extract were then investigated in vitro on cell viability, apoptosis and cell cycle using fluorescence microscopy and flow cytometry, and the molecular mechanism against human lung cancer cells A549 was further studied by western blot assays. The in vivo anti-cancer effect of the extract was evaluated in A549 xenograft mice model by histochemical assay, and tumor growth, microvascular density (MVD) and Ki67 expression were also measured. In addition, acute oral toxicity test of the extract was executed in mice.

RESULTS

SDEA extract mainly contained eight biflavonoids. The extract caused the loss of mitochondrial membrane potential and induced cell apoptosis by upregulating Bax, downregulating Bcl-2, activating caspase-9 and caspase-3 and blocked the cell cycle in S phase. The extract reduced expression of antigen Ki67, decreased MVD, and significantly inhibited the tumor growth. The extract did not show apparent oral acute toxicity in healthy mice.

CONCLUSION

The SDEA extract exerted anti-tumor effect through activating mitochondrial pathways and reducing Ki67 expression and MVD. Low oral acute toxicity suggested it a promising chemotherapy agent.

Preparative Isolation of Two Prenylated Biflavonoids from the Roots and Rhizomes of Sinopodophyllum emodi by Sephadex LH-20 Column and High-Speed Counter-Current Chromatography

Two prenylated biflavonoids, podoverines B–C, were isolated from the dried roots and rhizomes of Sinopodophyllum emodi using a Sephadex LH-20 column (SLHC) and high-speed counter-current chromatography (HSCCC). The 95% ethanol extract was partitioned with ethyl acetate in water. Target compounds from the ethyl acetate fraction were further enriched and purified by the combined application of SLHC and HSCCC. n-Hexane–ethyl acetate–methanol–water (3.5:5:3.5:5, v/v) was chosen as the two phase solvent system. The flow rate of mobile phase was optimized at 2.0 mL·min⁻¹. Finally, under optimized conditions, 13.8 mg of podoverine B and 16.2 mg of podoverine C were obtained from 200 mg of the enriched sample. The purities of podoverines B and C were 98.62% and 99.05%, respectively, as determined by HPLC. For the first time, podoverins B and C were found in the genus Sinopodophyllum. Their structures were determined by spectroscopic methods (HR-ESI-MS, ¹H-NMR, ¹³C-NMR, HSQC, HMBC). Their absolute configurations were elucidated by comparison of their experimental and calculated ECD spectra. The cytotoxic activities were evaluated against MCF-7 and HepG2 cell lines. The separation procedures proved to be practical and economical, especially for trace prenylated biflavonoids from traditional Chinese medicine.

Antitumor Activities of Ethyl Acetate Extracts from Selaginella doederleinii Hieron In Vitro and In Vivo and Its Possible Mechanism

The antitumor activities of ethyl acetate extracts from Selaginella doederleinii Hieron (SD extracts) in vitro and in vivo and its possible mechanism were investigated. HPLC method was developed for chemical analysis. SD extracts were submitted to 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay on different cells, flow cytometry, and RT-PCR analysis using HepG2 cell and antitumor activity in vivo using H-22 xenograft tumor mice. Six biflavonoids from SD extracts were submitted to molecular docking assay. The results showed that SD extracts had considerable antitumor activity in vitro and in vivo without obvious toxicity on normal cells and could induce cell apoptosis. The mechanisms of tumorigenesis and cell apoptosis induced by SD extracts may be associated with decreasing the ratio of bcl-2 and bax mRNA level, activating caspase-3, suppressing survivin, and decreasing the gene expression of COX-2, 5-LOX, FLAP, and 12-LOX mRNA. The main active component in SD extracts is biflavonoids and some exhibited strong interactions with COX-2, 5-LOX, 12-LOX, and 15-LOX. These results offering evidence of possible mechanisms of SD extracts suppress cell proliferation and promote apoptosis and provide the molecular theoretical basis of clinical application of S. doederleinii for cancer therapy.

Antiviral Activity of Total Flavonoid Extracts from Selaginella moellendorffii Hieron against Coxsackie Virus B3 In Vitro and In Vivo

The antiviral activity of total flavonoid extracts from Selaginella moellendorffii Hieron and its main constituents amentoflavone were investigated against coxsackie virus B3 (CVB3). When added during or after viral infection, the extracts and amentoflavone prevented the cytopathic effect (CPE) of CVB3, as demonstrated in a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) colorimetric assay, with a 50% inhibitory concentration (IC50) from 19 ± 1.6 to 41 ± 1.2 μg/mL and 25 ± 1.2 to 52 ± 0.8 μg/mL, respectively. KM mice were used as animal models to test the extracts' activity in vivo. Oral administration of the total flavonoid extracts at 300 mg/kg/day significantly reduced mean viral titers in the heart and kidneys as well as mortality after infection for 15 days. The experimental results demonstrate that in vitro and in vivo the model mice infected with CVB3 can be effectively treated by the total flavonoid extracts from Selaginella moellendorffii Hieron.