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Vouacapoua americana (Fabaceae) is an economically important tree in the Amazon region and used for its highly resistant heartwood as well as for medicinal purposes. Despite its frequent use, phytochemical investigations have been limited and rather focused on ecological properties than on its pharmacological potential. In this study, we investigated the phytochemistry and bioactivity of V. americana stem bark extract and its constituents to identify eventual lead structures for further drug development. Applying hydrodistillation and subsequent GC-MS analysis, we investigated the composition of the essential oil and identified the 15 most abundant components. Moreover, the diterpenoids deacetylchagresnone ( 1 ), cassa-13(14),15-dien-oic acid ( 2 ), isoneocaesalpin H ( 3 ), (+)-vouacapenic acid ( 4 ), and (+)-methyl vouacapenate ( 5 ) were isolated from the stem bark, with compounds 2 and 4 showing pronounced effects on Methicillin-resistant Staphylococcus aureus and Enterococcus faecium , respectively. During the structure elucidation of deacetylchagresnone ( 1 ), which was isolated from a natural source for the first time, we detected inconsistencies regarding the configuration of the cyclopropane ring. Thus, the structure was revised for both deacetylchagresnone ( 1 ) and the previously isolated chagresnone. Following our works on Copaifera reticulata and Vatairea guianensis , the results of this study further contribute to the knowledge of Amazonian medicinal plants.

Major threats to the human lifespan include cancer, infectious diseases, diabetes, mental degenerative conditions and also reduced agricultural productivity due to climate changes, together with new and more devastating plant diseases. From all of this, the need arises to find new biopesticides and new medicines. Plants and microorganisms are the most important sources for isolating new metabolites. Lampedusa Island host a rich contingent of endemic species and subspecies. Seven plant species spontaneously growing in Lampedusa, i.e., Atriplex halimus L. (Ap), Daucus lopadusanus Tineo (Dl), Echinops spinosus Fiori (Es) Glaucium flavum Crantz (Gf) Hypericum aegypticum L: (Ha), Periploca angustifolia Labill (Pa), and Prasium majus L. (Pm) were collected, assessed for their metabolite content, and evaluated for potential applications in agriculture and medicine. The HPLC-MS analysis of n-hexane (HE) and CH2Cl2 (MC) extracts and the residual aqueous phases (WR) showed the presence of several metabolites in both organic extracts. Crude HE and MC extracts from Dl and He significantly inhibited butyrylcholinesterase, as did WR from the extraction of Dl and Pa. HE and MC extracts showed a significant toxicity towards hepatocarcinoma Huh7, while Dl, Ha and Er HE extracts were the most potently cytotoxic to ileocecal colorectal adenocarcinoma HCT-8 cell lines. Most extracts showed antiviral activity. At the lowest concentration tested (1.56 μg/mL), Dl, Gf and Ap MC extracts inhibited betacoronavirus HCoV-OC43 infection by> 2 fold, while the n-hexane extract of Pm was the most potent. In addition, at 1.56 μg/mL, potent inhibition (>10 fold) of dengue virus was detected for Dl, Er, and Pm HE extracts, while Pa and Ap MC extracts dampened infections to undetectable levels. Regarding to phytotoxicity, MC extracts from Er, Ap and Pm were more effective in inhibiting tomato rootlet elongation; the same first two extracts also inhibited seed cress germination while its radicle elongation, due to high sensitivity, was affected by all the extracts. Es and Gf MC extracts also inhibited seed germination of Phelipanche ramosa. Thus, we have uncovered that many of these Lampedusa plants displayed promising biopesticide, antiviral, and biological properties.

The genus Quercus supplies a large amount of residual material (e.g., bark, acorns, leaves, wood), the valorization of which can favor a supply of antioxidant polyphenols to be used in the pharmaceutical, nutraceutical, or cosmeceutical sector. The recovery of specialized metabolites could also benefit livestock feeding, so much so that polyphenols have gained attention as rumen fermentation modifiers and for mitigating the oxidative imbalance to which farm animals are subject. In this context, leaves of Quercus robur L. from Northern Germany were of interest and the alcoholic extract obtained underwent an untargeted profiling by means of ultra-high-performance liquid chromatography/high-resolution tandem mass spectrometry (UHPLC-HRMS/MS) techniques. As triterpenes and fatty acids occurred, the alcoholic extract fractionation pointed out the obtainment of a polyphenol fraction, broadly constituted by coumaroyl flavonol glycosides and condensed tannins. Total phenol, flavonoid and condensed tannins content assays, as well as antiradical (DPPH ● and ABTS +● ) and reducing activity (PFRAP) were carried out on the alcoholic extract and its fractions. When the effects on rumen liquor was evaluated in vitro in terms of changes in fermentation characteristics, it was observed that oak leaf extract and its fractions promoted an increase in total volatile fatty acids and differently modulated the relative content of each fatty acid.

The widespread seagrass Zostera marina contains a new diarylheptanoid heterodimer, zosterabisphenone C ( 1 ), featuring an unprecedented rearrangement of one of its benzene rings to a cyclopentenecarbonyl unit. The planar structure and absolute configuration of zosterabisphenone C were elucidated by a combination of spectroscopic (MS, ECD, and low-temperature NMR) and computational (DFT-NMR and DFT-ECD) evidence. Consistent with the previously isolated zosterabisphenones, compound 1 was selectively cytotoxic against HCT 116 adenocarcinoma colon cancer cells, reducing their viability by 73% at 10 μM (IC 50 of 7.6 ± 1.1 μM). The biosynthetic origin of zosterabisphenone C ( 1 ) from an oxidative rearrangement of zosterabisphenone A ( 4 ) is proposed.

Ethnopharmacological Relevance: Species of the genera Hieracium and Pilosella have been used in folk medicine for centuries in many parts of the world. The most wiedly used species is P. officinarum Vaill., included in the British and French Pharmacopoeias and sold as part of different commercial products., Aim of the Study: This review critically appraises the state-of-art of ethnopharmacology, specialised metabolites, bioactivities, and toxicity of members of Hieracium and Pilosella. Thus, gaps in scientific knowledge can be identified, also focusing on the development of products with pharmacological applications., Materials and Methods: Literature data of Hieracium and Pilosella species were mainly retrieved using different electronic databases such as Web of Science, Google Scholar, SciFinder, and PubMed. Other electronic resources included worldwide databases on ethnobotany, ethnopharmacology, and phytochemistry as well as government reports. Additionally, ancient texts and local information such as PhD and MSc theses, and books were consulted., Results: A comprehensive analysis of the above mentioned sources revealed that only 34 out of the about 850 described species within the genera Hieracium and Pilosella have been reported in the context of traditional medicinal and ethnobotanical knowledge. The most often mentioned species is P. officinarum which has been widely used due to its diuretic effects. Other popular uses of Hieracium and Pilosella species include the treatment of skin, gastric, and intestinal diseases as well as respiratory and vascular ailments. Moreover, taxa of the two genera have been used as antiobiotics, antiseptics, antidiabetics, tonics, antiepileptics, antiphlogistics, emetics, wound healing drugs, astringents, haemostatics, and detoxificants. Finally, uses as a wild vegetable, fodder, plant for hunting and for charming rituals have also been mentioned. Phytochemical research revealed a richness in phenolic compounds and flavonoids. Moreover, coumarins, sesquiterpene lactones, terpenoids, and phytosterols were found in Hieracium and Pilosella. Experimental research conducted to support traditional uses mainly include in vitro tests, while assays based on in vivo models (including humans) are rather limited. Also, the vast majority of the studies did not identify the compounds responsible for the detected bioactivities. These established bioactivities include antidiabetic, anti-inflammatory, antibacterial, antimycotic, antiviral, cytotoxic and antiproliferative, diuretic, gastroprotective, antiepileptic, hypotensive, anti-obesity, arthropodicidal, and skin rejuvenating activities. Finally, limited toxicity studies have been conducted on members of Hieracium and Pilosella., Conclusion: Taxa belonging to Hieracium and Pilosella have been confirmed to exert diuretic, anti-inflammatory, and antimicrobial effects, which is in line with their long traditional use. Moreover, the above mentioned fields of application hint to the most promising routes for the development of new marketable products. Nonetheless, additional data from an in-depth research on bio-active specialised metabolites such as sesquiterpenoids, sesquiterpene lactones, and coumarines, their bioactivities and toxicity, and their biosynthesis are still warranted., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Two diarylheptanoid heterodimers, zosterabisphenones A ( 1 ) and B ( 2 ), were isolated from the seagrass Zostera marina . They feature unprecedented catechol keto tautomers, stable because of steric constraints. Their structure elucidation was based on extensive low-temperature NMR studies and ECD and MS data, with the essential aid of DFT prediction of NMR and ECD spectra. Zosterabisphenone B ( 2 ) was selectively cytotoxic against the adenocarcinoma colon cancer cell line HCT116 with IC 50 3.6 ± 1.1 μM at 48 h.

European beech ( Fagus sylvatica L.) is a deciduous tree, widely distributed in Europe and largely appreciated for its wood and nutritive nuts. Beech leaf also enjoys food use as salad, but an understanding of its nutraceutical value is still far from being achieved. Indeed, and also taking into account beech leaf as a consistent biomass residue available beechwood production and use, it needs to be explored as a valuable renewable specialized source of bioactive molecules. In this context, an untargeted ultra-high-performance liquid chromatography hyphenated with high resolution mass spectrometry (UHPLC-HRMS) approach was favorably applied to a beech leaf alcoholic extract, which also was evaluated for its antiradical capability (by means of assays based on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and [2,2'-azinobis-(3-ethylbenzothiazolin-6-sulfonic acid)] (ABTS) radical cation) and its ferric ion reducing power. Redox mitochondrial activity towards Caco-2 cells paved the way to explore the extract's capability to inhibit intracellular Reactive Oxygen Species (ROS) using 2',7'dichlorofluorescin diacetate (DCFH-DA) assay. Hydroxycinnamoyl derivatives, mainly belonging to the chlorogenic acid class, and flavonoids were the main constituents. Uncommon flavanone C -glycosides were also found, together with a plentiful flavonol diversity. Cell-free and cell-based assays highlight its dose-dependent antioxidant efficacy, providing a foundation for further investigation of beech leaf constituents and its valorization and use as a reservoir of bioactive natural products with potential nutraceutical applications.

In our ongoing research for the discovery of new constituents with antimyeloma activity, we investigated 15 compounds present in the aerial parts of Leontodon saxatilis for their cytotoxic potential against NCI-H929, U266, and OPM2 cell lines. One of the isolated compounds displayed a new natural product and was identified as 5-feruloyl-2α-hydroxyquinic acid after LC-MS and NMR experiments. Of the remaining compounds, cichoric acid and three flavone glycosides, apigenin 4'- O -β-d-glucoside, luteolin 7- O -β-d-glucoside and luteolin 4'- O -β-d-glucoside, showed moderate cytotoxic activity, whereas the effects of two aglyones apigenin and luteolin were more pronounced. Though the cytotoxic potential of the two aglycones (against other cell lines) was reported in various studies, our work moreover showed that cooccurrence of these two compounds with similar components of lower activity led to comparable results and at the same time minimized the damage of healthy fibroblast cells. Thus, our work could be a starting point for additional studies on the synergistic effect of similar components against myeloma cell lines., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The majority of the population in Bangladesh uses traditional plant-based medicines to manage various ailments, including central nervous system (CNS) disorders. This review presents ethnobotanical information and relevant scientific studies on plants used in traditional healthcare for the management of various CNS disorders in Bangladesh. The information on the medicinal plants of Bangladesh effective against CNS disorders published in scientific journals, books, and reports was compiled from different electronic databases using specific key words. The present article provides comprehensive information on a total of 224 medicinal plant species belonging to 81 families used for the treatment of CNS disorders by the various peoples of Bangladesh. In total, we reviewed more than 290 relevant papers. In this study, leaves were found as the most often used plant organ, followed by roots, fruits, whole plants, barks, seeds, stems, rhizomes, and flowers. The Fabaceae family contributes the highest number of used species, followed by Rubiaceae, Lamiaceae, Cucurbitaceae, Vitaceae, Euphorbiaceae, Malvaceae, and Zingiberaceae. The most frequently used species (in decreasing order) are Asparagus racemosus, Centella asiatica, Stephania japonica, Aegle marmelos, Coccinia grandis, Tabernaemontana divaricata, Bacopa monnieri, Abroma augusta, and Scoparia dulcis. This review may serve as a starting point for a rational search for neuroactive natural products against CNS disorders within the Flora of Bangladesh.

Zosteraphenols, two new tetracyclic diarylheptanoids were isolated from the seagrass Zostera marina . The rotameric equilibrium of the strained tetracyclic structures, involving a diastereomeric minor rotamer with opposite axial chirality, resulted in coalescent NMR spectra. Although the elusive minor rotamer was only characterized with 1 H chemical shifts, the excellent agreement between experimental and DFT-calculated chemical shifts of both rotamers unequivocally supported this analysis. Absolute configuration of zosteraphenols was determined by DFT prediction of their ECD spectra.

Introduction: Hieracium s. str. represents one of the largest and most complex genera of flowering plants. As molecular genetics seems unlikely to disentangle intricate relationships within this reticulate species complex, analysis of flavonoids and phenolic acids, known as good chemosystematic markers, promise to be more reliable. Data about pharmacological activity of Hieracium species are scarce., Objective: Evaluation of the chemosystematic significance of flavonoids and phenolic acids of methanol extracts of aerial flowering parts of 28 Hieracium species from the Balkans. Additionally, investigation of antioxidant potentials of the extracts., Methods: Comparative qualitative and quantitative analysis of flavonoids and phenolic acids was performed by LC-MS. Multivariate statistical data analysis included non-metric multidimensional scaling (nMDS), unweighted pair-group arithmetic averages (UPGMA) and principal component analysis (PCA). Antioxidant activity was evaluated using three colorimetric tests., Results: Dominant phenolics in almost all species were luteolin type flavonoids, followed by phenolic acids. Although the investigated Hieracium species share many compounds, the current classification of the genus was supported by nMDS and UPGMA analyses with a good resolution to the group level. Hieracium naegelianum was clearly separated from the other investigated species. Spatial and ecological distances of the samples were likely to influence unexpected differentiation of some groups within H. sect. Pannosa. The vast majority of dominant compounds significantly contributed to differences between taxa. The antioxidant potential of the extracts was satisfactory and in accordance with their phenolics composition., Conclusions: Comparative LC-MS analysis demonstrated that flavonoids and phenolic acids are good indicators of chemosystematic relationships within Hieracium, particularly between non-hybrid species and groups from the same location. Copyright © 2017 John Wiley & Sons, Ltd., (Copyright © 2017 John Wiley & Sons, Ltd.)

Seagrasses are the only higher plants living in fully marine environments; they play a significant role in coastal ecosystems. Seagrasses inhabit the coastal shelves of all continents except Antarctica and can grow in depths of up to 90 m. Because of their eminent ecological importance, innumerous studies have been dedicated to seagrasses and their ecology. However, the phytochemistry has not been equally well investigated yet and many of the existing studies in chemical ecology are only investigating the chemistry at the level of compound classes, e.g. phenolics, and not at the level of chemically defined metabolites. In the present review, the existing literature on secondary metabolites of seagrasses, their known source seagrasses, their bioactivity, and ecological function are compiled and critically assessed. Moreover, research gaps are highlighted and avenues for future research are discussed. Currently, a total of 154 chemically defined natural products have been reported from the about 70 seagrass species known worldwide. Compounds reported include simple phenols derivatives (four compounds), phenylmethane derivatives (14 compounds), phenylethane derivatives (four compounds), phenylpropane derivatives including their esters and dimers (20 compounds), chalkones (four compounds), flavonoids including catechins (57 compounds), phenylheptanoids (four compounds), one monoterpene derivative, one sesquiterpene, diterpenoids (13 compounds), steroids (31 compounds), and one alkaloid. Most of the existing bioactivity studies of seagrass metabolites and extracts have been directed to potential cytotoxic, antimicrobial, or antimacrofouling activity. Antimicrobial studies have been performed towards panels of both human pathogens and ecologically relevant pathogens. In the antimacrofouling studies, investigations of the potential of zosteric acid from the genus Zostera are the most numerous and have yielded so far the most interesting results. Studies on the chemical ecology of seagrasses often have been focused on variation in phenolic compounds and include but are not limited to studies on variation due to abiotic factors, seasonal variation, variation in response to grazing by fish or sea urchins, or following microbial attack., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

This review summarizes all reports on sesquiterpene lactones and their immediate precursors from the Cichorieae (Lactuceae) tribe of the Asteraceae. A total of 360 compounds have been reported from this tribe. The reported substances belong to three classes of sesquiterpenoids: guaianolides (243 compounds), eudesmanolides (73 compounds), and germacranolides (44 compounds). Sources of these compounds encompass 139 taxa from 31 different genera. The distribution of these lactones within the tribe Cichorieae is discussed in a chemosystematic context. Moreover, some general ideas about the interpretation of chemosystematic data are discussed.

In continuation of our studies of altitudinal effects on secondary metabolite profile of flowering heads from taxa of the Asteraceae, we investigated phenolic contents and radical scavenging potential from cultivated plants of Arnica montana cv. ARBO during the growing seasons 2003, 2004, and 2005. By conducting experiments on potted plants, we excluded that differences in phenolic contents from plants grown at different altitudes were related primarily to differences in soil composition at these sites. To assess altitudinal and interseasonal variation, plants of A. montana cultivar ARBO were grown in nine experimental plots at altitudes between 590 and 2,230 m at Mount Patscherkofel near Innsbruck, Austria. In all growing seasons and regardless of the soil the plants were grown in, the proportion of flavonoids with vicinal-free hydroxy groups in ring B to flavonoids lacking this feature, and the total amount of caffeic acid derivatives, significantly increased with elevation. These increases of antioxidant phenolics corresponded to an increase of the radical scavenging potential of extracts from plants grown at different altitudes. The results are discussed in regard to previous studies that suggest that enhanced UV-B radiation and decreased temperatures trigger augmented biosynthesis of UV-absorbing and antioxidant phenolics in higher plants.