Profiling Key Aroma Compounds of Senecio glaucus L. and their Antimicrobial and Antioxidant Activities: Multiplex of GC-MS, NMR and In Silico Studies.

The essential oils of Senecio plants have been used to treat a wide range of ailments. The current study aimed to extract the essential oil of Senecio glaucus obtained from Egypt's Nile delta and determine its chemical profile using GC-MS and NMR analysis. Then, the antimicrobial activity of the oil has been investigated against different fungal and bacterial strains. In addition, its activity as radical scavenger has been evaluated using DPPH, ABTS, and metal chelating techniques. The results revealed the identification of 50 compounds representing 98.80 % of the oil total mass. Sesquiterpenes, including dehydrofukinone (27.15 %) and 4,5-di-epi-aristolochene (10.27 %), as well as monoterpenes, including p-cymene (4.77 %), represented the most predominant constituents. The dehydrofukinone has been isolated and structurally confirmed using 1D and 2D NMR techniques. The oil has showed remarkable antifungal activity against Candida glabrata and C. albicans where the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values were 3.13 µg/mL and 1.50 µg/mL and 12.50 µg/mL and 6.30 µg/mL, respectively that could be attributed to the sesquiterpene ketones present in the aerial tissues of the plant. Also, this oil inhibited the growth of the tested bacteria with MIC ranging from 12.50-100.00 µg/mL. In comparison to ascorbic acid and Trolox, the EO had remarkable scavenging activity of DPPH, ABTS and metal chelating with IC50 values of 313.17±13.4, 493.83±20.1, and 409.13±16.7 µg/mL. The docking studies of the identified compounds of the oil to different microbial targets, including Gyrase B and α-sterol demethylase, showed that the phytol possessed the best binding affinities toward the active sites of both enzymes with ΔG=-7.42 and -7.78 kcal/mol, respectively. In addition, the phytol revealed the highest binding affinity to tyrosine kinase Hck with ΔG=-7.44 kcal/mol.

Antimicrobial metabolite of Cordyceps tenuipes targeting MurE ligase and histidine kinase via in silico study.

Cordyceps spp. are widely healthy foods around the world with several traditional uses and bio-functionalities. The chemical characterization of ethyl acetate-soluble extract of the entomopathogenic fungus Cordyceps tenuipes NBRC 111,630 afforded two new metabolites with 1,6-dioxaspiro[4.4]nonane motif, tenuipesone A (1) and tenuipesone B (2), along with four well-known metabolites (3-6). The elucidation of the chemical structures was carried out via extensive spectroscopic experiments including FTIR, HRMS, 1D-NMR, and 2D-NMR. The probable biosynthetic pathway of 1 and 2 was hypothesized. From the six isolates, beauvericin (6) exhibited antimicrobial activity against Bacillus subtilis and Staphylococcus aureus with respective MIC of 6.25 and 12.5 µM. Docking results exhibited that beauvericin (6) has significant binding affinities against MurE and HK proteins with ΔG = - 8.021 and - 8.585 kcal/mol, respectively. KEY POINTS: • Six compounds, including two new, were isolated from the entomopathogenic fungus Cordyceps tenuipes. • Plausible biosynthetic pathway of compounds 1, 2, 4, and 5 was hypothesized. • Beauvericin (6) exhibited significant antimicrobial activity against Bacillus subtilis and Staphylococcus aureus alongside binding affinities against MurE and HK proteins in MOE study.

Sarcoconvolutums F and G: Polyoxygenated Cembrane-Type Diterpenoids from Sarcophyton convolutum, a Red Sea Soft Coral.

Natural products and chemical analogues are widely used in drug discovery, notably in cancer and infectious disease pharmacotherapy. Sarcophyton convolutum (Alcyoniidae) a Red Sea-derived soft coral has been shown to be a rich source of macrocyclic diterpenes and cyclized derivatives. Two previously undescribed polyoxygenated cembrane-type diterpenoids, sarcoconvolutums F (1) and G (2), as well as four identified analogues (3-6) together with a furan derivate (7) were isolated from a solvent extract. Compounds were identified by spectroscopic techniques, including NMR, HREIMS, and CD, together with close spectral comparisons of previously published data. Sarcoconvolutum F (1) contains a rare 1-peroxid-15-hydroxy-10-ene functionality. Isolated metabolites (1-7) were screened against lung adenocarcinoma (A549), cervical cancer (HeLa) and oral cavity carcinoma (HSC-2) lines. Compound 4 exhibited an IC50 56 µM and 55 µM against A549 and HSC-2 cells, respectively.

Marylosides A-G, Norcycloartane Glycosides from Leaves of Cymbidium Great Flower 'Marylaurencin'.

Seven novel norcycloartane glycosides, maryloside A-G (1-7), were isolated from the leaves of Cymbidium Great Flower 'Marylaurencin', along with a known norcycloartane glycoside, cymbidoside (8). These structures were determined on the basis of mainly NMR experiments as well as chemical degradation and X-ray crystallographic analysis. The isolated compounds (1-6 and 8) were evaluated for the inhibitory activity on lipopolysaccharide (LPS) and interferon-γ (IFN-γ)-stimulated nitric oxide (NO) production in RAW 264.7 cells. Consequently, 1 and 3 exhibited moderate activity.

MAO-A Inhibitory Potential of Terpene Constituents from Ginger Rhizomes-A Bioactivity Guided Fractionation.

BACKGROUND: In the search for novel antidepressive drug candidates, bioguided fractionation of nonpolar constituents present in the oleoresin from ginger rhizomes (Zingiber officinale Roscoe, Zingiberaceae) was performed. This particular direction of the research was chosen due to the existing reports on the antidepressive properties of ginger total extract. The search for individual metabolites acting as MAO-A inhibitors, which correspond to the apparent effect of the total extract, is the subject of this work. METHODS: Hexane extracts from ginger rhizomes were fractionated by using column chromatography (including silica gel impregnated with silver nitrate) and semi-preparative high-performance chromatography. For the activity assessment, an in vitro monoamine oxidase A (MAO-A) inhibition luminescence assay was performed on 10 purified terpenes: 1,8-cineole, α-citronellal, geraniol, ß-sesquiphellandrene, γ-terpinen, geranyl acetate, isobornyl acetate, terpinen-4-ol, (E,E)-α-farnesene, and α-zingiberene. RESULTS: Geraniol and (-)-terpinen-4-ol were found to be the strongest enzyme inhibitors with inhibition of 44.1% and 42.5%, respectively, at a concentration of 125 µg/mL. No differences in the inhibition potential were observed for the different groups of terpenes: sesquiterpenes, monoterpenes, or sesquiterpene alcohols; however, the two most active compounds contained a hydroxyl moiety. CONCLUSIONS: Terpene constituents from ginger's extract were found to exhibit moderate inhibitory properties against the MAO-A enzyme in in vitro tests.

In Vitro Antitrypanosomal Activity of the Secondary Metabolites from the Mutant Strain IU-3 of the Insect Pathogenic Fungus Ophiocordyceps coccidiicola NBRC 100683.

During the search for new antitrypanosomal drug leads, four antitrypanosomal compounds, of three depsipeptides and one nortriterpenoid, were isolated from cultures of the mutant strain IU-3 of the insect pathogenic fungus Ophiocordyceps coccidiicola NBRC 100683. Their structures were identified by the analysis of high resolution-electron ionization (HR-EI)-MS and HR-FAB-MS, and (1)H- and (13)C-NMR spectra, including extensive two dimensional (2D)-heteronuclear NMR experiments, and comparison with literature data for destruxin A (1), destruxin B (2), destruxin E chlorohydrin (3) and helvolic acid (4). Compounds 1-4 showed in vitro antitrypanosomal activity against Trypanosoma brucei brucei GUTat3.1 with IC50 values of 0.33, 0.16, 0.061 and 5.08 µg/mL, respectively.

Isolation of C-29 oxygenated oleanane triterpenoids and a (+)-muurolene type sesquiterpenoid from the fruiting bodies of Fuscoporia torulosa and their bioactivities.

Basidiomycetes with a wide variety of skeletons of secondary metabolites can be expected to be the source of new interesting biological compounds. During our research on basidiomycetes, two new C-29 oxygenated oleanane-type triterpenes (1 and 2) and torulosacid (3), a muurolene type sesquiterpenoid with a five-membered ether ring along with nine known compounds (4-12), were isolated from the MeOH extract of the fruiting bodies of Fuscoporia torulosa. The structures of 1-3 were determined by NMR and HREIMS analysis. Further studies on the stereochemistry of 3 were conducted using X-ray crystallographic analysis and comparison of experimental and calculated ECD spectra. In the antimicrobial assay of isolates, 1, 7, and 9 showed growth inhibitory activity against methicillin-resistant Staphylococcus aureus and other gram-positive strains. Isolation of oleanane type triterpenes from fungi including basidiomycetes, is a unique report that could lead to further isolation of new compounds and the discovery of unique biosynthetic enzymes.

Ternifolipyrons A-J: new cytotoxic α-pyrones from Isodon ternifolius (D. Don) Kudô.

Isodon ternifolius (D.Don) Kudô is an important Asian herb used in traditional medicine against several diseases. Nineteen compounds were isolated from the dichloromethane-methanol (1 : 1) extract of I. ternifolius roots, including ten new α-pyrone derivatives, named ternifolipyrons A-J. The chemical structures of the isolates were determined by a combination of 1D and 2D NMR, along with LR- and HRMS spectroscopy. The absolute configurations of the α-pyrone derivatives were constructed based upon the X-ray signal crystal of the bromobenzoyl derivative of 1 as well as the electronic circular dichroism (ECD). All isolates (1-19) were investigated for their growth-inhibitory potential towards CCRF-CEM-leukemia cells at a fixed concentration of 30 µM. The compounds which exerted more than 50% inhibition at this concentration, compounds (7, 10, 12, 15-17), were tested at a different concentration range to determine their IC50 values in CCRF-CEM leukemia, MDA-MB-231 triple-negative breast cancer, and MCF7 breast cancer cell lines. Ursolic acid (16) showed the most potent activity against the three cancer cell lines with IC50 values of 8.37, 18.04, and 18.93 µM, respectively.

Bifusicoumarins A-D: Cytotoxic 3S-dihydroisocoumarins from the entomopathogenic fungus Cordyceps bifusispora (NBRC 108997).

Cordyceps is a genus of ascomycete fungi with some of them being edible and/or having a long tradition in Chinese medicine. The chemical characterization of a solvent extract of the entomopathogenic fungus Cordyceps bifusispora afforded four undescribed coumarins, bifusicoumarin A-D (1-4), along with previously reported metabolites (5-8). Structural elucidation was performed via NMR, UV and HRMS analyses, X-ray single crystal diffraction and experimental ECD. A high throughput resazurin reduction assay, that measures cell viability, indicated that 5 has a IC50 between 1 and 15 µM for several assayed tumor lines. Moreover, a protein-interaction network indicated that C. bifusispora is a promising source of additional antitumor metabolites based on SwissTargetPrediction software predictions.

Xanthone glucoside from an insect pathogenic fungus Conoideocrella luteorostrata NBRC106950.

A new compound, 3-O-(4-O-methyl-ß-D-glucopyranosyl) xanthone (1) was isolated from the culture of Conoideocrella luteorostrata NBRC106950. The structure of 1 was mainly determined by 1H, 13C, 2D-NMR and HREIMS spectral analyses. The absolute configuration of 4-O-methylglucopyranosyl moiety was determined by the optical rotation of aqueous layer of hydrolyzed 1 as D-configuration.

Pentacyclic triterpenoids, fuscotorunones A and B, with ε-caprolactone in ring E from Fuscoporia torulosa.

Fuscoporia torulosa (Pers.) (Hymenochaetaceae) is a mushroom forming woody fruiting body on living or dead trees. Two curious pentacyclic triterpenoids, fuscotorunones A and B, each of which has a unique ε-caprolactone in ring E, were isolated from the fruiting bodies of F. torulosa. The structures of fuscotorunones A and B were elucidated using MS analyses, IR spectrum and extensive 2D-homo and heteronuclear NMR data interpretation. Furthermore, a predicted biosynthetic pathway from 2,3-oxidosqualene to fuscotorunones A and B in F. torulosa is proposed.

Two novel oxetane containing lignans and a new megastigmane from Paronychia arabica and in silico analysis of them as prospective SARS-CoV-2 inhibitors.

The chemical characterization of the extract of the aerial parts of Paronychia arabica afforded two oxetane containing lignans, paronychiarabicine A (1) and B (2), and one new megastigmane, paronychiarabicastigmane A (3), alongside a known lignan (4), eight known phenolic compounds (5-12), one known elemene sesquiterpene (13) and one steroid glycoside (14). The chemical structures of the isolated compounds were constructed based upon the HRMS, 1D, and 2D-NMR results. The absolute configurations were established via NOESY experiments as well as experimental and TDDFT-calculated electronic circular dichroism (ECD). Utilizing molecular docking, the binding scores and modes of compounds 1-3 towards the SARS-CoV-2 main protease (Mpro), papain-like protease (PLpro), and RNA-dependent RNA polymerase (RdRp) were revealed. Compound 3 exhibited a promising docking score (-9.8 kcal mol-1) against SARS-CoV-2 Mpro by forming seven hydrogen bonds inside the active site with the key amino acids. The reactome pathway enrichment analysis revealed a correlation between the inhibition of GSK3 and GSK3B genes (identified as the main targets of megastigmane treatment) and significant inhibition of SARS-CoV-1 viral replication in infected Vero E6 cells. Our results manifest a novel understanding of genes, proteins and corresponding pathways against SARS-CoV-2 infection and could facilitate the identification and characterization of novel therapeutic targets as treatments of SARS-CoV-2 infection.

Paralemnolins X and Y, New Antimicrobial Sesquiterpenoids from the Soft Coral Paralemnalia thyrsoide.

The organic extracts of the Red Sea soft coral Paralemnalia thyrsoides has led to the identification of two neolemnane-type sesquiterpenoids: paralemnolins X and Y (1, 2). In addition to these newly characterized compounds, ten known metabolites (3-12) were isolated. Previously reported compounds were elucidated by literature comparison of spectroscopic data (1D and 2D NMR as well as MS data). In vitro antimicrobial activity was investigated for compounds (1-12) against Staphylococcus aureus, Escherichia coli, Candida albicans and Aspergillus niger. Compound 5 showed antimicrobial activity against all assayed microorganisms.

Uncarinic acid C plus IFN-γ generates monocyte-derived dendritic cells and induces a potent Th1 polarization with capacity to migrate.

Uncarinic acid C (URC) is triterpene isolated from Uncaria rhynchophylla and modulates human DC function in a fashion that favors Th1 cell polarization depending on TLR4 signaling. The induction of dendritic cells (DC) is critical for the induction of Ag-specific T lymphocyte responses and may be essential for the development of human vaccines relying on T cell immunity. Monocyte-derived DC used as adjuvant cells in cancer immunotherapy and have shown promising results. We studied the effect of interferon's (IFN-α and IFN-γ) and TNF-α on phenotypic and functional maturation, and cytokine production of URC-primed DC in vitro. Human monocytes were exposed to either URC alone, or in combination with TNF-α, IFN-α or IFN-γ, and thereafter co-cultured with naïve T cells. We found that the expression levels of CD1a, CD83 and HLA-DR on URC-primed DC were influenced by IFN-γ and IFN-γ augmented the T cell stimulatory capacity in allo MLR to URC-primed DC. Moreover, the production of IL-12p70 by URC-primed DC was enhanced by IFN-γ. IL-12p70 production by URC-primed DC alone was influenced following treatment with anti-TLR4 mAb, but not DC differentiated with URC plus IFN-γ. URC plus IFN-γ-primed DC induced a substantial increase in the secretion of IFN-γ by T cells, which is dependent on IL-12 secretion. DC maturated with URC plus IFN-γ had an intermediate migratory capacity towards CCL19 and CCL21. In addition, the expression levels of CCR7 on URC-primed DC were enhanced by IFN-γ. In contrast, surface molecule up-regulation and function of URC-primed DC were slightly enhanced by TNF-α, and IFN-α. These results suggest that the enhancement of Th1 cells polarization to URC-primed DC induced by IFN-γ depends on the activation of IL-12p70 and independent on TLR4. DC differentiated with URC in combination with IFN-γ might be used on DC-based vaccine for cancer immunotherapy.

Sarcoehrenbergilides D-F: cytotoxic cembrene diterpenoids from the soft coral Sarcophyton ehrenbergi.

A solvent extract of the soft coral Sarcophyton ehrenbergi afforded cembrene diterpenoids, sarcoehrenbergilid D-F (1-3). Chemical structures were established by modern spectroscopic techniques with absolute stereochemistries determined by circular dichroism (CD) and time-dependent density functional theory electronic CD calculations (TDDFT-ECD). Cytotoxicity activities for 1-3 were evaluated against three human cancer cell lines: lung (A549), colon (Caco-2) and liver (HepG2).

New alkaloidal metabolites from cultures of entomopathogenic fungus Cordyceps takaomontana NBRC 101754.

Two new alkaloidal metabolites, cordytakaoamides A (1) and B (2), as well as, 2-[(2-hydroxyethyl) amino] benzoic acid (3) and 2E-decenamide (4), and three known compounds (5-7) were isolated from ethyl acetate and n-butanol soluble portions of the entomopathogenic fungus, Cordyceps takaomontana NBRC 101754. Compounds 3 and 4 were isolated here for first time from natural resources. The chemical structures were established depending upon spectroscopic techniques such as 1D, 2D NMR, and HRMS. The absolute configuration of 1 and 2 was elucidated via the total synthesis of 1 as well as the experimental circular dichroism. Compound 3 was confirmed by a signal crystal X-ray analysis.

Recent Advances in Kaempferia Phytochemistry and Biological Activity: A Comprehensive Review.

BACKGROUND: Plants belonging to the genus Kaempferia (family: Zingiberaceae) are distributed in Asia, especially in the southeast region, and Thailand. They have been widely used in traditional medicines to cure metabolic disorders, inflammation, urinary tract infections, fevers, coughs, hypertension, erectile dysfunction, abdominal and gastrointestinal ailments, asthma, wounds, rheumatism, epilepsy, and skin diseases. OBJECTIVE: Herein, we reported a comprehensive review, including the traditional applications, biological and pharmacological advances, and phytochemical constituents of Kaempheria species from 1972 up to early 2019. MATERIALS AND METHODS: All the information and reported studies concerning Kaempheria plants were summarized from library and digital databases (e.g., Google Scholar, Sci-finder, PubMed, Springer, Elsevier, MDPI, Web of Science, etc.). The correlation between the Kaempheria species was evaluated via principal component analysis (PCA) and agglomerative hierarchical clustering (AHC), based on the main chemical classes of compounds. RESULTS: Approximately 141 chemical constituents have been isolated and reported from Kaempferia species, such as isopimarane, abietane, labdane and clerodane diterpenoids, flavonoids, phenolic acids, phenyl-heptanoids, curcuminoids, tetrahydropyrano-phenolic, and steroids. A probable biosynthesis pathway for the isopimaradiene skeleton is illustrated. In addition, 15 main documented components of volatile oils of Kaempheria were summarized. Biological activities including anticancer, anti-inflammatory, antimicrobial, anticholinesterase, antioxidant, anti-obesity-induced dermatopathy, wound healing, neuroprotective, anti-allergenic, and anti-nociceptive were demonstrated. CONCLUSIONS: Up to date, significant advances in phytochemical and pharmacological studies of different Kaempheria species have been witnessed. So, the traditional uses of these plants have been clarified via modern in vitro and in vivo biological studies. In addition, these traditional uses and reported biological results could be correlated via the chemical characterization of these plants. All these data will support the biologists in the elucidation of the biological mechanisms of these plants.

Diterpene, 16-phyllocladanol enhances Th1 polarization induced by LPS-primed DC, but not TNF-alpha-primed DC.

16-Phyllocladanol is diterpene isolated form the heartwood of Cryptomeria japonica. We demonstrate that the effect of 16-phyllocladanol on the phenotypic and functional maturation of human monocytes-derived DC in vitro. Human monocytes were exposed to 16-phyllocladanol alone, or in combination with LPS and thereafter co-cultured with naïve T cells. The expression levels of CD83 and HLA-DR on LPS-primed DC were enhanced by 16-phyllocladanol. 16-Phyllocladanol dose-dependently augmented the T cell stimulatory capacity in an allo MLR to LPS-primed DC and the production of IL-12p70 by LPS-primed DC. The cytokine production by 16-phyllocladanol-primed DC was not inhibited by anti-TLR2 and 4 mAbs. IFN-gamma secretion from naïve T cells co-cultured with DC differentiated with LPS was also augmented by 16-phyllocladanol. These results suggest that the enhancement of Th1 cells polarization to LPS-primed DC induced by 16-phyllocladanol via the activation of IL-12p70 and independent on TLR2 or TLR4.

Diterpenes drive Th1 polarization depending on IL-12.

Sandaracopimaric acid and Sandaracopimaradiene-3beta-ol are diterpenes isolated from the heatwood of Cryptomeria japonica and are pharmacologically active substances. Dendritic cells (DC) are key antigen presenting cells (APC), which link innate and adaptive immunity, ultimately activating antigen-specific T cells. We demonstrate that Sandaracopimaric acid and Sandaracopimaradiene-3beta-ol activate humans DC as documented by phenotypic and functional maturation and altered cytokine production. The expression of the co-stimulatory molecules such as CD83, CD86 and HLA-DR on Sandaracopimaric acid- and Sandaracopimaradiene-3beta-ol-primed DC was enhanced. Sandaracopimaric acid- and Sandaracopimaradiene-3beta-ol-primed DC also enhanced the T cell stimulatory capacity in an allo MLR. Naive T cells co-cultured with Sandaracopimaric acid- or Sandaracopimaradiene-3beta-ol-primed DC turned into typical Th1 cells, which produced large quantities of IFN-gamma and released small amounts of IL-4 depending on IL-12 secretion. Sandaracopimaric acid- or Sandaracopimaradiene-3beta-ol-primed DC had a high migration to macrophage inflammatory protein (MIP)-3beta. These results suggest that some diterpenes modulate human DC function in a fashion that favors Th1 cell polarization and may be used on DC-based vaccines for cancer immunotherapy.

Differential regulation of DC function by Siphonodiol.

Siphonodiol is a polyacetylene diol isolated from marine sponges Callyspongia sp. We demonstrate that the effect of Siphonodiol on the phenotypic and functional maturation of human monocyte derived DC in vitro. Human monocytes were exposed to Siphonodiol alone, or in combination with LPS and thereafter co-cultured with naïve T cells. The expression levels of CD1a, CD80, CD83, CD86 and HLA-DR on LPS-primed DC were partially enhanced by Siphonodiol. Siphonodiol augmented the T cell stimulatory capacity in an allo MLR to LPS-primed DC. Siphonodiol dose-dependently enhanced the production of IL-12p70 by LPS-primed DC and this cytokine production was inhibited by anti-TLR4 mAb. IFN-gamma secretion from naive T cells co-cultured with DC differentiated with LPS was augmented by Siphonodiol. These results suggest that the enhancement of Th1 cells polarization to LPS-primed DC induced by Siphonodiol depends on TLR4 and via the activation of IL-12p70.