Sarcanoids A and B, two new lindenane-type sesquiterpenoid dimers from the aerial parts of Sarcandra glabra.

Sarcanoids A and B (1 and 2), two new lindenane-type sesquiterpenoid dimers with a γ-hydroxysenecioate moiety at C-15', were isolated from the ethyl acetate extract of Sarcandra glabra. The structures were elucidated by extensive analysis of spectroscopic data, and their absolute configurations were determined by single-crystal X-ray crystallography. Compounds 1 and 2 showed moderate inhibitory activities on the nitric oxide (NO) production induced by lipopolysaccharide (LPS) in RAW264.7 macrophages.

(±)-Sarcanan A, a pair of new enantiomeric dihydrobenzofuran neolignans from the aerial parts of Sarcandra glabra.

(+)-Sarcanan A (1a) and (-)-Sarcanan A (1b), a pair of new dihydrobenzofuran neolignan enantiomers, together with six known compounds (2-7), were isolated from the aerial parts of Sarcandra glabra. Their structures were elucidated by spectroscopic analysis, and the absolute configurations of 1a and 1b were determined by analyses of the electronic circular dichroism (ECD) data. All compounds were evaluated for their inhibitory effects on the nitric oxide (NO) production induced by lipopolysaccharide (LPS) in RAW264.7 cells, and compounds 2-4 exhibited moderate inhibition against NO production.

Phylogeny and biogeography of the Japanese rhinoceros beetle, Trypoxylus dichotomus (Coleoptera: Scarabaeidae) based on SNP markers.

The Japanese rhinoceros beetle Trypoxylus dichotomus is one of the largest beetle species in the world and is commonly used in traditional Chinese medicine. Ten subspecies of T. dichotomus and a related Trypoxylus species (T. kanamorii) have been described throughout Asia, but their taxonomic delimitations remain problematic. To clarify issues such as taxonomy, and the degree of genetic differentiation of Trypoxylus populations, we investigated the genetic structure, genetic variability, and phylogeography of 53 specimens of Trypoxylus species from 44 locations in five Asian countries (China, Japan, Korea, Thailand, and Myanmar). Using specific-locus amplified fragment sequencing (SLAF-seq) techniques, we developed 330,799 SLAFs over 114.16M reads, in turn yielding 46,939 high-resolution single nucleotide polymorphisms (SNPs) for genotyping. Phylogenetic analysis of SNPs indicated the presence of three distinct genetic groups, suggesting that the various subspecies could be treated as three groups of populations. PCA and ADMIXTURE analysis also identified three genetic clusters (North, South, West), which corresponded to their locations, suggesting that geographic factors were important in maintaining within population homogeneity and between population divergence. Analyses of SNP data confirmed the monophyly of certain subspecies on islands, while other subspecies (e.g., T. d. septentrionalis) were found to be polyphyletic and nested in more than one lineage. AMOVA demonstrated high level of differentiation among populations/groups. Also, pairwise F ST values revealed high differentiation, particularly between South and West, as well as between North and South. Despite the differentiation, measurable gene flow was inferred between genetic clusters but at varying rates and directions. Our study demonstrated that SLAF-seq derived markers outperformed 16S and COII sequences and provided improved resolution of the genetic differentiation of rhinoceros beetle populations from a large part of the species' range.

Reactive oxygen species altering the metabolite profile of the marine-derived fungus Dichotomomyces cejpii F31-1.

To investigate the influence of reactive oxygen species (ROS) on the secondary metabolites of the marine-derived fungus Dichotomomyces cejpii F31-1, hydrogen peroxide (H2O2) was added to the GPY culture medium. The HPLC chromatogram of the EtOAc extract of the culture broth was distinct from that of the H2O2 free GPY medium. Further study of the metabolites in the GPY medium with H2O2 resulted in the discovery of eight known compounds. Among them, (22E)-5α, 8α-epidioxyergosta-6, 22-dien-3ß-ol (2) and ergosta-4,6,8(14),22-tetraene-3-one (3) were present in the highest concentration, while ergosterol and diketopiperazines are abundant in the H2O2 free medium. Additionally, a new compound, dichocetide D (1) containing a chlorine element and a known ergosterol (10) were isolated from the H2O2 free medium. (22E)-5α, 8α-epidioxyergosta-6, 22-dien-3ß-ol (2) exhibited moderate cytotoxic activity against human prostate cancer cell line LNCaP-C4-2B.

l-Phenylalanine Alters the Privileged Secondary Metabolite Production in the Marine-Derived Fungus Trichoderma erinaceum F1-1.

The effects of a single-amino-acid culture strategy on secondary metabolite production in the marine-derived fungus Trichoderma erinaceum F1-1 were investigated by culturing the fungus in GPY medium supplemented or not supplemented with l-phenylalanine. A suite of secondary metabolites, including seven terpenoids (1-7) and one polyketide (8), among which are four new compounds, harziandione A (1), cyclonerodiols A and B (3, 4), and trichodermaerin A (6), were isolated from the GPY medium without l-phenylanine, whereas 18 aromatic compounds (9-26), including six new compounds, trichoderolides A-F (9, 10, and 14-17), were isolated from the culture grown in the GPY medium with l-phenylalanine. The structures of the new compounds were determined by high-resolution mass spectrometry, NMR spectroscopic analysis, optical rotation calculations, chemical methods, and X-ray crystallography. Compounds 10, 12, 13, and 26 exhibited cytotoxic activities against MDA-MB-435 human melanocyte cancer cells. Compound 26 was cytotoxic to A549 adenocarcinomic human alveolar basal epithelial cells.

A simple method to discriminate Guangchenpi and Chenpi by high-performance thin-layer chromatography and high-performance liquid chromatography based on analysis of dimethyl anthranilate.

Citri Reticulatae Pericarpium (CRP), the dried pericarp of Citrus reticulata Blanco, can be divided into "Guangchenpi" (GCP, the dried pericarps derived from Citrus reticulata 'Chachi') and "Chenpi" (CP, the dried pericarps derived from other cultivars of Citrus reticulata Blanco). To discriminate between GCP and CP, a simple and reliable high-performance thin-layer chromatography (HPTLC) method was firstly developed to analyze the volatile compound dimethyl anthranilate, and a high-performance liquid chromatography (HPLC) method was established to simultaneously quantify dimethyl anthranilate and three predominant flavonoids (hesperidin, nobiletin and tangeretin) in CRP samples. Both the HPTLC analysis and HPLC-orthogonal partial least squares discrimination analysis (OPLS-DA) indicated that GCP can be effectively distinguished from CP based on analysis of dimethyl anthranilate. Our results indicated that dimethyl anthranilate can be used as a marker compound for discrimination of GCP and CP. This work provided a convenient approach which might be applied for quality evaluation of CRP.

Chloraserrtone A, a Sesquiterpenoid Dimer from Chloranthus serratus.

Chloraserrtone A (1), a new sesquiterpenoid dimer with two lindenane-type sesquiterpenoid monomers bridged by two six-membered rings, was obtained from Chloranthus serratus. A combination of UV, IR, NMR, HRESIMS, and X-ray diffraction data were used to elucidate the structure of 1. Compound 1 represents the first lindenane-type sesquiterpenoid dimer with extremely unique C-15-C-15', C-4-C-6', and C-6-C-11' linkages to form two six-membered rings between the monomeric units. A plausible biosynthesis toward chloraserrtone A is proposed. This new compound (1), together with the known lindenane dimers (2-11), were assessed for their inhibitory effects on lipopolysaccharide-induced NO production in RAW264.7 cells. Compound 6 showed activity with an IC50 value of 3.7 µM.

A new labdane-type diterpenoid from Leonurus japonicus.

Five fractions prepared from the crude extract of Leonurus japonicus were examined in order to determine their cytotoxic potential. Under the bioassay guidance, a new labdane-type diterpenoid (1), and nine known ones (2-10) along with a seco-labdane (11) were isolated from the aerial parts of Leonurus japonicus. The structure elucidation was primarily based on comprehensive spectroscopic analyses, including HRESIMS, IR, and 1D and 2D NMR methods. Compound 4 (6ß-hydroxy-15,16-epoxylabda-8,13(16),14-trien-7-one) exhibited potential cytotoxicity against HeLa cell line (IC50 = 23.75 µM).

Polyketides and Alkaloids from the Marine-Derived Fungus Dichotomomyces cejpii F31-1 and the Antiviral Activity of Scequinadoline A against Dengue Virus.

In our continuous chemical investigation on the marine-derived fungus Dichotomomyces cejpii F31-1, two new polyketides dichocetides B-C (1, 2), two new alkaloids dichotomocejs E-F (3, 4), and three known fumiquinozalines: scequinadoline A (5), quinadoline A (6), and scequinadoline E (7) were discovered from the culture broth and the mycelium in the culture medium, by the addition of l-tryptophan and l-phenylalanine. Their chemical structures were established by one dimensional (1D), two dimensional (2D) nuclear magnetic resonance (NMR) and high resolution mass spectrometry (HR-MS) data. Among them, scequinadoline A (5) exhibited significant inhibitory activity against dengue virus serotype 2 production by standard plaque assay, equivalent to the positive control andrographlide. Scequinadoline A (5) possesses the potential for further development as a dengue virus inhibitor.

Three new cassane diterpenes from the seeds of Caesalpinia minax Hance.

Four fractions were prepared from the crude extract of Caesalpinia minax Hance and the inhibitory activity of nitric oxide (NO) production release of RAW 264.7 cells stimulated by lipopolysaccharide (LPS) was evaluated. The ethyl acetate (EtOAc) fraction showed obvious inhibitory effect. Bioassay-guided fractionation led to the isolation of three new cassane diterpenes, caesalmin X (1), caesalmin Y (2) and caesalmin Z (3), together with 19 known cassane diterpenoids (4-22). Their structures were mainly characterised on the basis of extensive spectroscopic analyses and comparison with reported data. Moreover, three compounds (20-22) which possessed furanditerpenoid 7,17-lactone structures, displayed moderate activities, with IC50 value of 29.85, 27.38 and 25.40 µM, respectively.

A new C-glycosyl flavone and a new neolignan glycoside from Passiflora edulis Sims peel.

A new C-glycosyl flavone, Chrysin-8-C-(2″-O-ß-6-deoxy-glucopyranosyl)-ß-D-glucopyranoside (1), a new neolignan glycoside, citrusin G (2), as well as 15 known compounds (3-17) were isolated from the peel of Passiflora edulis Sims. The structure determinations were primarily based on comprehensive spectroscopic analyses, and the absolute configuration of 2 were unequivocally determined by the CD experiment and chemical transformation. Compound 1 represents the rare examples of the flavonoid featuring a deoxy glucose sugar moiety. Compounds 5, 7 and 9 exhibited moderate inhibitory effects on nitric oxide (NO) production stimulated by lipopolysaccharide (LPS) in RAW 264.7 cells, with IC50 values of 34.92, 16.12 and 26.67 µM, respectively.

Diverse Secondary Metabolites from the Marine-Derived Fungus Dichotomomyces cejpii F31-1.

By adding l-tryptophan and l-phenylalanine to GPY medium, twenty-eight compounds, including amides, polyketides, a sesquiterpenoid, a diterpenoid, a meroterpenoid, diketopiperazines, ß-carbolines, fumiquinazolines, and indole alkaloids, were discovered from the marine-derived fungus Dichotomomyces cejpii F31-1, demonstrating the tremendous biosynthetic potential of this fungal strain. Among these compounds, four amides dichotomocejs A-D (1-4), one polyketide dichocetide A (5), and two diketopiperazines dichocerazines A-B (15 and 16) are new. The structures of these new compounds were determined by interpreting detailed spectroscopic data as well as calculating optical rotation values and ECD spectra. Obviously, Dichotomomyces cejpii can effectively use an amino acid-directed strategy to enhance the production of nitrogen-containing compounds. Dichotomocej A (1) displayed moderate cytotoxicity against the human rhabdomyosarcoma cell line RD with an IC50 value of 39.1 µM, and pityriacitrin (22) showed moderate cytotoxicity against the human colon carcinoma cell line HCT116 with an IC50 value of 35.1 µM.

Amino Acid-Directed Strategy for Inducing the Marine-Derived Fungus Scedosporium apiospermum F41-1 to Maximize Alkaloid Diversity.

By feeding various amino acids to the marine fungus Scedosporium apiospermum F41-1, 22 diverse alkaloids, including 14 new compounds, were obtained. Scedapins A-E (1-5) possess a rare skeleton of a pyrazinoquinazolinedione and an imidazoindolone/indolone linked by a tetrahydrofuran ring. Scedapin C (3) is the first example of fumiquinazoline that contains an aminosulfonyl group. Their structures were determined by HRMS, NMR, ECD calculations and X-ray single-crystal diffraction analysis. The biosynthetic pathways of fumiquinazolines 1-18 were proposed. Scedapin C (3) and scequinadoline D (8) displayed significant antiviral activity against hepatitis C.

Hsp90 inhibitor induces KG-1a cell differentiation and apoptosis via Akt/NF-κB signaling.

Heat-shock protein 90 (Hsp 90) acts as a molecular chaperone that maintains protein stability and regulates cell proliferation, survival, differentiation and apoptosis. The present study investigated the effect of Hsp90 inhibition on human acute myeloid leukemia (AML) cells using the novel small-molecule inhibitor SNX-2112. We found that SNX-2112 more potently inhibited KG-1a cell growth than the classical Hsp90 inhibitor 17-(2-dimethylaminoethyl)amino­17-demethoxygeldanamycin as determined by CCK-8 assay. Flow cytometry was used to examine the cell cycle, differentiation, and apoptosis, and western blotting and qRT-PCR were used to analyze the underlying mechanism. The results revealed that low concentrations of SNX-2112 arrested the cells in the G2/M phase and induced their differentiation and apoptosis, possibly by suppressing Akt and inhibitor of κB kinase, a component of the nuclear factor (NF)-κB signaling pathway. We also found that SNX-2112 increased the expression of the differentiation transcription factors PU.1 and CCAAT­enhancer-binding protein-α. Thus, SNX-2112 induced KG-1a cell differentiation, cell cycle arrest and apoptosis via modulation of Akt and NF-κB signaling, suggesting that it is a promising therapeutic agent for the treatment of AML.

Secondary Metabolites from the Marine-Derived Fungus Dichotomomyces sp. L-8 and Their Cytotoxic Activity.

Bioassay-guided isolation of the secondary metabolites from the fungus Dichotomomyces sp. L-8 associated with the soft coral Lobophytum crassum led to the discovery of two new compounds, dichotones A and B (1 and 2), together with four known compounds including dichotocejpin C (3), bis-N-norgliovictin (4), bassiatin (5) and (3R,6R)-bassiatin (6). The structures of these compounds were determined by 1D, 2D NMR and mass spectrometry. (3R,6R)-bassiatin (6) displayed significant cytotoxic activities against the human breast cancer cell line MDA-MB-435 and the human lung cancer cell line Calu3 with IC50 values of 7.34 ± 0.20 and 14.54 ± 0.01 µM, respectively, while bassiatin (5), the diastereomer of compound 6, was not cytotoxic.

Solanerioside A, an unusual 14,15-dinor-cyclophytane glucoside from the leaves of Solanum erianthum.

Solanerioside A (1), the first example of a diterpenoid glucoside featuring a 14,15-dinor-cyclophytane scaffold, together with three known terpene glucosides (2-4) were isolated from the methanol extract of the leaves of Solanum erianthum (Solanaceae). The structure of 1 was mainly characterised on the basis of extensive spectroscopic analyses, especially from the 2D NMR spectra. In addition, the spectroscopic data of (6E, 10E)-5,12-dihydroxy-ß-nerolidol 5-O-ß-D-glucopyranoside (3) were reported for the first time. However, these compounds did not display obvious inhibition of LPS-induced NO release in RAW264.7 cells and anti-tumour activity against A549, HepG2, Hela and MCF-7 cells in vitro.

Chlojaponilactone B from Chloranthus japonicus: Suppression of Inflammatory Responses via Inhibition of the NF-κB Signaling Pathway.

Bioassay-guided fractionation of an ethanolic extract of Chloranthus japonicus led to the isolation of the known lindenane-type sesquiterpenoid chlojaponilactone B (1). This compound exhibited pronounced inhibition of nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Further anti-inflammatory assays showed that 1 suppressed the levels of some key inflammation mediators, such as iNOS, TNF-α, and IL-6, in a dose-dependent manner, and reduced the ear thickness and neutrophil infiltration in 12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated mice. A mechanistic study revealed that compound 1 exerted its anti-inflammatory effects via the suppression of the NF-κB signaling pathway, which inhibited NF-κB-dependent transcriptional activity, IκBα phosphorylation, and p65 nuclear translocation. In contrast, chlojaponilactone B (1) was found to exert little influence on the MAPK signaling pathway.

Two Additional New Compounds from the Marine-Derived Fungus Pseudallescheria ellipsoidea F42-3.

Two additional new compounds, pseudellone D (1) and (5S,6S)-dihydroxylasiodiplodin (3), along with the two known compounds lasiodipline F (2), (5S)-hydroxylasiodiplodin (4) were isolated from the marine-derived fungus Pseudallescheria ellipsoidea F42-3 associated with the soft coral Lobophytum crassum. Their structures, including absolute configurations, were elucidated on the basis of the corresponding spectroscopic data and electronic circular dichroism (ECD) spectra.

Enantiomeric Neolignans and a Sesquiterpene from Solanum erianthum and Their Absolute Configuration Assignment.

One pair of new C-8-C-3'/C-7-O-C-4' linked neolignan enantiomers (1a/1b) and one new guaiane sesquiterpene (2) first featuring the 1(2),9(10)-conjugated double bond were isolated from the stems of Solanum erianthum (Solanceae). Their structures were characterized on the basis of extensive spectroscopic analyses, especially from their 2D nuclear magnetic resonance (NMR) spectra. The absolute configurations of 1a/2b were rigorously elucidated by electronic circular dichroism (ECD) experiments combined with the reversed helicity rule for the 2,3-dihydrobenzo[b]furan chromophore, and compound 2 is the first report on the sterochemical assignment of a guaiane sesquiterpene by using the allylic axial chirality rule for the conjugated diene chromophore in combination with the calculated ECD spectrum.

Five New Cytotoxic Metabolites from the Marine Fungus Neosartorya pseudofischeri.

The marine fungus Neosartorya pseudofischeri was isolated from Acanthaster planci from the South China Sea. In a preliminary bioactivity screening, the crude methanol extract of the fungal mycelia showed significant inhibitory activity against the Sf9 cell line from the fall armyworm Spodoptera frugiperda. Five novel compounds, including 5-olefin phenylpyropene A (1), 13-dehydroxylpyripyropene A (4), deacetylsesquiterpene (7), 5-formyl-6-hydroxy-8-isopropyl-2- naphthoic acid (9) and 6,8-dihydroxy-3-((1E,3E)-penta-1,3-dien-1-yl)isochroman-1-one (10), together with eleven known compounds, phenylpyropene A (2) and C (3), pyripyropene A (5), 7-deacetylpyripyropene A (6), (1S,2R,4aR,5R,8R,8aR)-1,8a-dihydroxy-2-acetoxy-3,8-dimethyl-5- (prop-1-en-2-yl)-1,2,4a, 5,6,7,8,8a-octahydronaphthalene (8), isochaetominine C (11), trichodermamide A (12), indolyl-3-acetic acid methyl ester (13), 1-acetyl-ß-carboline (14), 1,2,3,4-tetrahydro-6-hydroxyl-2-methyl-l,3,4-trioxopyrazino[l,2-a]-indole (15) and fumiquinazoline F (16), were obtained. The structures of these compounds were determined mainly by MS and NMR data. The absolute configuration of 9 was assigned by the single-crystal X-ray diffraction studies. Compounds 1-11 and 15 showed significant cytotoxicity against the Sf9 cells from S. frugiperda.