Diverse ansamycin derivatives from the marine-derived Streptomyces sp. ZYX-F-97 and their antibacterial activities.

Four new ansamycin derivatives, named 1,19-epithio-geldanamycin A (1), 17-demethoxylherbimycin H (2), herbimycin M (3), and seco-geldanamycin B (4), together with eight known ansamycin analogues (5-12) were isolated from the solid fermentation of marine-derived actinomycete Streptomyces sp. ZYX-F-97. The structures of new compounds were elucidated by extensive spectroscopic analysis as well as nuclear magnetic resonance (NMR) and electronic circular dichroism (ECD) calculations. All the compounds were assayed for their antibacterial activity. Among them, compounds 4, 8, and 12 exhibited remarkable inhibition against Listeria monocytogenes with minimum inhibitory concentrations (MIC) values ranging from 8 µg·mL-1 to 64 µg·mL-1, and displayed moderate inhibition against methicillin-resistant Staphylococcus aureus (MRSA) with MIC value of 64 µg·mL-1. Compounds 4, 8, 9, and 12 showed moderate inhibition activities against both Staphylococcus aureus and Bacillus subtilis with MIC values ranging from 32 µg·mL-1 to 128 µg·mL-1.

Chryseobacterium herbae Isolated from the Rhizospheric Soil of Pyrola calliantha H. Andres in Segrila Mountain on the Tibetan Plateau.

A non-motile, Gram-staining-negative, orange-pigmented bacterium called herbae pc1-10T was discovered in Tibet in the soil around Pyrola calliantha H. Andres' roots. The isolate thrived in the temperature range of 10-30 °C (optimal, 25 °C), pH range of 5.0-9.0 (optimum, pH = 6.0), and the NaCl concentration range of 0-1.8% (optimal, 0%). The DNA G+C content of the novel strain was 37.94 mol%. It showed the function of dissolving organophosphorus, acquiring iron from the environment by siderophore and producing indole acetic acid. Moreover, the genome of strain herbae pc1-10T harbors two antibiotic resistance genes (IND-4 and AdeF) encoding a ß-lactamase, and the membrane fusion protein of the multidrug efflux complex AdeFGH; antibiotic-resistance-related proteins were detected using the Shotgun proteomics technology. The OrthoANIu values between strains Chryseobacterium herbae pc1-10T; Chryseobacterium oleae CT348T; Chryseobacterium kwangjuense KJ1R5T; and Chryseobacterium vrystaatense R-23566T were 90.94%, 82.96%, and 85.19%, respectively. The in silico DDH values between strains herbae pc1-10T; C. oleae CT348T; C. kwangjuense KJ1R5T; and C. vrystaatense R-23566T were 41.7%, 26.6%, and 29.7%, respectively. Chryseobacterium oleae, Chryseobacterium vrystaatense, and Chryseobacterium kwangjuense, which had 16S rRNA gene sequence similarity scores of 97.80%, 97.52%, and 96.75%, respectively, were its closest phylogenetic relatives. Chryseobacterium herbae sp. nov. is proposed as the designation for the strain herbae pc1-10T (=GDMCC 1.3255 = JCM 35711), which represented a type species based on genotypic and morphological characteristics. This study provides deep knowledge of a Chryseobacterium herbae characteristic description and urges the need for further genomic studies on microorganisms living in alpine ecosystems, especially around medicinal plants.

Structure and Function Analysis of Cultivated Meconopsis integrifolia Soil Microbial Community Based on High-Throughput Sequencing and Culturability.

(1) Background: The structure, function, and community interactions of soil microbial communities of cultivated Meconopsis integrifolia were characterized by studying this alpine flower and traditional endangered Tibetan medicine. (2) Methods: Soil bacteria and fungi were studied based on high-throughput sequencing technology. Bacteria were isolated using culturomics and functionally identified as IAA-producing, organic phosphorus-dissolving, inorganic phosphorus-dissolving, and iron-producing carriers. (3) Results: The dominant bacterial phyla were found to be Proteobacteria and Acidobacteria, and unclassified_Rhizobiales was the most abundant genus. Ascomycota and Mortierellomycota were the dominant fungal phyla. The bacteria were mainly carbon and nitrogen metabolizers, and the fungi were predominantly Saprotroph-Symbiotroph. The identified network was completely dominated by positive correlations, but the fungi were more complex than the bacteria, and the bacterial keystones were unclassified_Caulobacteraceae and Pedobacter. Most of the keystones of fungi belonged to the phyla Ascomycetes and Basidiomycota. The highest number of different species of culturable bacteria belonged to the genus Streptomyces, with three strains producing IAA, 12 strains solubilizing organic phosphorus, one strain solubilizing inorganic phosphorus, and nine strains producing iron carriers. (4) Conclusions: At the cost of reduced ecological stability, microbial communities increase cooperation toward promoting overall metabolic efficiency and enabling their survival in the extreme environment of the Tibetan Plateau. These pioneering results have value for the protection of endangered Meconopsis integrifolia under global warming and the sustainable utilization of its medicinal value.

Lanostane Triterpenoids and Ergostane Steroids from Ganoderma luteomarginatum and Their Cytotoxicity.

Macrofungus Ganoderma luteomarginatum is one of the main species of Ganoderma fungi distributed in Hainan province of China, the fruiting bodies of which have been widely used in folk as a healthy food to prevent tumors. To explore the potential cytotoxic constituents from G. luteomarginatum, the phytochemical investigation on the ethyl acetate soluble fraction of 95% ethanolic extract from the fruiting bodies of this fungus led to the isolation of twenty-six lanostane triterpenoids (1-26), including three undescribed ones (1-3), together with eight ergostane steroids (27-34). The structures of three new lanostane triterpenoids were elucidated as lanosta-7,9(11)-dien-3ß-acetyloxy-24,25-diol (1), lanosta-7,9(11)-dien-3-oxo-24,26-diol-25-methoxy (2), and lanosta-8,20(22)-dien-3,11,23-trioxo-7ß,15ß-diol-26-oic acid methyl ester (3) by the analysis of 1D, 2D NMR, and HRESIMS spectroscopic data. All isolates were assayed for their cytotoxic activities using three human cancer cell lines (K562, BEL-7402, and SGC-7901) and seven lanostane triterpenoids (1, 2, 7, 13, 18, 22, and 24), and one ergostane steroid (34) showed definite cytotoxicity with IC50 values that ranged from 6.64 to 47.63 µg/mL. Among these cytotoxic lanostane triterpenoids, compounds 2 and 13 showed general cytotoxicity against three human cancer cell lines, while compounds 1 and 18 exhibited significant selective cytotoxicity against K562 cells with IC50 values of 8.59 and 8.82 µg/mL, respectively. Furthermore, the preliminary structure-cytotoxicity relationships was proposed.

An affinity interaction guided two-dimensional separation system for the screening of neuraminidase inhibitors from Reynoutria japonica Houtt. roots.

Discovering bioactive compounds from medicinal herbs is crucial for drug discovery. Ultrafiltration is often used in the screening of bioactive compounds from natural herbs because of its simple and rapid operations. However, the ultrafiltration results are often disturbed by the undissolved compounds and the non-target compounds, which reduces the accuracy of the results. Herein, an affinity interaction guided two-dimensional (2D) separation system was developed. Discovery of the potential neuraminidase (NA) inhibitors from the dried roots of Reynoutria japonica Houtt. (RRJ) was used as an example. Only the small molecules showing affinity interaction with NA could be screened by the affinity interaction guided 2D separation system. Firstly, the NA and crude extract were incubated to form a sample solution (containing NA-inhibitor complexes, NA, and three types of small molecules with different polarities) by affinity interaction. Then the sample solution was separated and detected by the 2D separation system. This aimed to reduce the interference of the undissolved compounds and non-target compounds, and pick out the NA-inhibitor complexes (NA-Is). The collected NA-Is were denatured to release small molecular inhibitors (Is) for LC-MS/MS analysis. Compared with the ultrafiltration, more obvious peak area differences were observed in the results, and four potential NA inhibitors were successfully identified. In all, we provided a simple strategy with better performance in the screening of natural bioactive compounds.

Mahuang Xixin Fuzi decoction ameliorates apoptosis via the mitochondrial-mediated signaling pathway in MCM cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Mahuang Xixin Fuzi Decoction (MXF), as a classical prescription of traditional Chinese medicine (TCM), has been used to treat the symptoms of fever, nasal congestion and headache in elderly people for almost a thousand years. AIM OF THE STUDY: The purpose of this study was to evaluate the effects and possible mechanisms of MXF on thermal stimulation-induced mouse cardiac myocytes (MCM) cell apoptosis. MATERIALS AND METHODS: The apoptosis of the MCM cell model was induced by a PCR-calculated temperature control system with a gradual heating pattern at 43 °C for 1 h. The cytotoxic effects were determined using real-time cell analyzer (RTCA) technology. Annexin V-FITC/7-AAD staining, and JC-1 fluorescence were used to assess apoptosis. Specific substrates, enzyme-linked immunosorbent assays (ELISAs), and Western blotting were used to identify proteins in the mitochondrial-mediated pathway. The identification of chemical components in the mouse heart was performed by ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry analysis. RESULTS: MXF inhibited apoptosis through the mitochondrial-mediated signaling pathway, including ameliorating ∆Ψm reduction, blocking mitochondrial Cyt C release, reducing Bax levels and increasing Bcl-2 levels, suppressing caspase-9 and caspase-3 activation in cytoplasmic fractions. Moreover, the components of MXF that act on the heart are mainly ephedra alkaloids and aconitine alkaloids. CONCLUSIONS: The findings demonstrated that MXF treatment markedly reduced MCM cell apoptosis induced by thermal stimulation, which may be ascribed to the mitochondrial-mediated signaling pathway.

Phenethoxy Derivatives with Anti-inflammatory Activities from the Betelnut Endophytic Trichoderma asperellum G10.

Eight new phenethoxy derivatives, trichoasperellins A-H (1-8), were isolated from the endophytic fungus Trichoderma asperellum G10 isolated from the medicinal plant Areca catechu L. The structures of these compounds were elucidated from spectroscopic data, J-based configurational analysis, and Mosher's methods. Compounds 1-4 and 6-8 bear one or two multioxidized C7 moieties with the same carbon skeleton. The carbon skeletons of compounds 6-8 are new, all containing three moieties connected via two acetal carbons similar to those of disaccharide glycosides. Compound 4 inhibited nitric oxide production with an IC50 value of 48.3 µM, comparable to that of the positive control indomethacin (IC50, 42.3 µM).

[Study on chemical constituents from fruiting bodies of Ganoderma calidophilum].

Chemical constituents were isolated and purified from fruiting bodies of Ganoderma calidophilum by various column chromatographic techniques, and their chemical structures were identified through combined analysis of physicochemical properties and spectral data. As a result, 11 compounds were isolated and identified as(24E)-lanosta-8,24-dien-3,11-dione-26-al(1), ganoderone A(2), 3-oxo-15α-acetoxy-lanosta-7,9(11), 24-trien-26-oleic acid(3),(23E)-27-nor-lanosta-8,23-diene-3,7,25-trione(4), ganodecanone B(5), ganoderic aldehyde A(6), 11ß-hydroxy-lucidadiol(7), 3,4-dihydroxyacetophenone(8), methyl gentiate(9), ganoleucin C(10), ganotheaecolumol H(11). Among them, compound 1 is a new triterpenoid. The cytotoxic activities of all of the compounds against tumor cell lines were evaluated. The results showed that compounds 1, 3, 4 and 6 showed cytotoxic activity against BEL-7402, with IC_(50) values of 26.55, 11.35, 23.23, 18.66 µmol·L~(-1); compounds 1 and 3-6 showed cytotoxic activity against K562, with IC_(50) values of 5.79, 22.16, 12.16, 35.32, and 5.59 µmol·L~(-1), and compound 4 showed cytotoxic activity against A549, with IC_(50) value of 42.50 µmol·L~(-1).

Anti-Respiratory Syncytial Virus Mechanism of Houttuynia cordata Thunb Exploration based on Network Pharmacology.

BACKGROUND AND OBJECTIVE: Respiratory Syncytial Virus (RSV) is the leading cause of infant lower respiratory tract infections with no mature vaccines and medicines available. Pneumonia caused by RSV kills many infants every year. There are unique advantages of Traditional Chinese Medicine (TCM) to fight against the virus. Houttuynia cordata Thunb is a commonly used antivirus medicine in TCM, but its mechanism has not been investigated. The current study explores the anti-RSV mechanism of H. cordata Thunb by means of network pharmacology and bioinformatics. METHODS: The candidate compounds of H. cordata Thunb and the potential targets were obtained from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), PubMed, CNKI, PubChem Database, and Swiss Target Prediction database. Then the potential targets and pathways of H. cordata Thunb against RSV were screened by GeneCards, GenCLiP 3, and NCBI Database. We developed a Protein-Protein Interactions (PPI) Network and Compound-Target-Pathway Network through the Cytoscape software. Furthermore, core targets were preliminary verified by Gene Expression Omnibus (GEO) database by bioinformatics methods. At last, the first six pathways were screened out to draw a map of the main target signal pathways. RESULTS: A total of 12 potentially active compounds and 47 potential interaction targets were screened. PPI Network and data from GEO showed that IL-6, STAT3, TNF, AKT1, PTGS2, SRC, and MAPK3 may play a core role in the antivirus process. KEGG enrichment pathway analysis predicted that H. cordata Thunb exerted its anti-RSV effect by regulating TNF, Rap1, HIF-1, PI3KAkt, MAPK, and VEGF signaling pathways. CONCLUSION: This study preliminarily predicted the main active compounds, targets and related pathways of H. cordata Thunb in the treatment of RSV-induced diseases, which laid a good foundation for further revealing its mechanism.

A rapid and practical prediction method for the Arizona solvent system family used in high speed countercurrent chromatography.

Selecting the appropriate solvent system is the key to the successful separation of samples by using countercurrent chromatography. Although high-speed countercurrent chromatography has been widely used in the separation and preparation of natural products, the selection of a solvent system has always been a stumbling block to the application of high-speed countercurrent chromatography. In order to explore a rapid and practical prediction method to select countercurrent chromatography solvent system, five linear prediction models of the Arizona solvent system family (HEMW) was established by using fourteen compounds with different structures and five HPLC columns of different brands. And two different solvent system selection methods (The partition coefficient K of the target compound in the solvent system was in the range of 0.25 < K < 2.5) were proposed for targeted separation of compounds and multi-component separation in a complex sample respectively. The appropriate HSCCC solvent system of five known compounds was determined by a HPLC analysis and a shake flask test and the appropriate HSCCC solvent system of two Chinese herbal extracts was determined by a HPLC analysis to verify the prediction method. In this study, solid-liquid partition chromatography (HPLC) and liquid-liquid partition chromatography (HSCCC) were linked by polarity to simplify the screening process of solvent system. This method reduced the difficulty and workload of solvent system selection, which provided methods and ideas for more solvent system prediction models.

Biphenyl metabolites from the patchouli endophytic fungus Alternaria sp. PfuH1.

Patchouli is a tropical medicinal and spice crop with high economic value, and the endophytic microorganism is also one of its important components and can provide new active compounds with medicinal use. In the present study, four new biphenyl compounds named 3-O-demethylaltenuisol (1), (-)-dialtenuisol (5) and (+)-dialtenuisol (6), and altertoxin VII (9), as well as six known related compounds, were isolated from the patchouli (Pogostemon cablin) endophytic fungus Alternaria sp. PfuH1. The structures of the new compounds were elucidated from spectroscopic data, ECD spectra analysis, and ECD calculations. Compounds 5 and 6 are a pair of dimeric axially chiral enantiomers. Compounds 2, 4, and 9 showed antibacterial activities against S. agalactiae with MIC values of 9.3, 85.3, and 17.3 µg/mL, respectively, and compound 4 also showed weak antibacterial activity against E. coli with MIC value of 128 µg/mL.

Meroterpenoids With Protein Tyrosine Phosphatase 1B Inhibitory Activities From the Fruiting Bodies of Ganoderma ahmadii.

Ganoderma fungi have long been used as functional foods and traditional medicines in Asian countries. Ganoderma ahmadii is one of the main species of Ganoderma fungi distributed in Hainan province of China, the fruiting bodies of which have been used in folk to lower blood sugar for a long time. A chemical investigation of the fruiting bodies of Ganoderma ahmadii led to the isolation of seven new meroterpenoids, named ganoduriporols F-L (1-7). The chemical structures of the compounds were elucidated by spectroscopic data including HRESIMS and 2D NMR. Compounds 5-7 represent the first examples of ganoduriporol-type meroterpenoids bearing oxepane rings in their skeletons. Compounds 1-4 showed inhibitory activity against protein tyrosine phosphatase 1B (PTP1B) comparable to the positive control Na3VO4, with IC50 values of 17, 20, 19, and 23 µM, respectively.

[Study on chemical constituents from fruiting bodies of Ganoderma australe].

Chemical constituents were isolated from the fruiting bodies of Ganoderma australe by various column chromatographic techniques and HPLC method, and their chemical structures were identified through the combined analysis of physicochemical properties and spectral data. Meanwhile, their α-glucosidase inhibitory activity and anti-oxidative ability were evaluated. Seven compounds were isolated from G. australe and were identified as 6-methoxyl-cyclo-(Phe-Ile)(1), applanoxidic acid A methyl ester(2), ergosta-7,22 E-dien-3ß-ol(3), cinnamic acid(4), 5α,8α-epidioxy-(20S,22E,24R)-ergosta-6,22-diene-3ß-ol(5), 1-(3, 4-dihydroxyphenyl) ethanone(6), salicylic acid(7) and benzoic acid(8). Among the compounds, compound 1 was a new cyclic dipeptide. Compound 2 was a new lanosta natural product, and compounds 4, 6, 7 and 8 were obtained from G. australe for the first time. Moreover, compounds 4 and 8 exhibited α-glucosidase inhibitory activity with inhibition rates of 36.8% and 34.7%, and compounds 4, 7 and 8 had a certain activity in DPPH free radical scavenging activity with IC_(50) values of 0.168, 0.458 and 0.170 g·L~(-1), respectively. The DPPH radical scavenging rate of compound 1 was 41.1%.

A phytochemical investigation of Stemona parviflora roots reveals several compounds with nematocidal activity.

Twelve undescribed compounds including six phenanthrene derivatives (parviphenanthrines A-F), two stilbene derivatives (parvistilbines A-B), three esters (parviesters A-C), and one sesquiterpenoid (parvidiol A) were isolated from the roots of Stemona parviflora, together with twenty-two known ones. The structures of the undescribed compounds were elucidated based on the analyses of their spectroscopic data. The absolute configuration of parviphenanthrine A was determined by the quantum ECD calculations. Parviphenanthrines A and E, stemanthrene A, stilbostenin E, 4-hydroxy-benzenepropanol-α-benzoate, and (E)-4-hydroxycinnamic acid methyl ester showed nematocidal activity against Meloidogyne incognita with IC50 values of 14.02 ±â€¯0.32, 2.51 ±â€¯0.13, 17.10 ±â€¯0.65, 2.05 ±â€¯0.07, 4.22 ±â€¯0.31, and 1.07 ±â€¯0.05 µM, respectively.

Daphnauranins A and B, two new antifeedants Isolated from Daphne aurantiaca roots.

Daphnauranins A (1) and B (2), two sesquiterpenoids were isolated from the roots of Daphne aurantiaca Diels. One is an unprecedented 5/7 oxacycloheptane ring system, the other is a sesquiterpene-lignan complex. Their structures were elucidated by comprehensive spectroscopic methods including MS and NMR. Their absolute configurations were further confirmed by the quantum ECD calculations. Daphnauranins A and B showed anti-insect activities against male fruit fly with anti-feeding rate up to 46.2±7.1 and 44.7±5.4% at 1mM, respectively.

Chrodrimanins O-S from the fungus Penicillium sp. SCS-KFD09 isolated from a marine worm, Sipunculusnudus.

Five new meroterpenoids, chrodrimanins O-S (1-5), as well as a known one (6), were isolated from the fermentation broth of Penicillium sp. SCS-KFD09 isolated from a marine worm, Sipunculusnudus, from Haikou Bay, China. The structures including the absolute configurations of the new compounds were unambiguously elucidated by spectroscopic data and ECD spectra analysis along with quantum ECD calculations. Among them, compound 1 represents the first example of an unusual trichlorinated meroterpenoid with an unique dichlorine functionality. Compounds 1 and 4-6 displayed inhibitory activity of protein tyrosine phosphatase 1B (PTP1B) with IC50 values of 71.6, 62.5, 63.1, and 39.6µM, respectively, and showed no apparent activity against three tumor cell lines (A549, HepG2, and Hela) and human umbilical vein endothelial cells (HUVEC) at 10µM.

Nematicidal Stemona Alkaloids from Stemona parviflora.

Eight new alkaloids, 3ß-n-butylstemonamine (1), 8-oxo-3ß-n-butylstemonamine (2), 3-n-butylneostemonine (3), 10-epi-3-n-butylneostemonine (4), 8-oxo-oxymaistemonine (5) protostemonine N4-oxide (6), (19S)-hydroxy-21-methoxystemofoline (7), and parvistemonine A (8), were isolated from the roots of Stemona parviflora, together with 17 known alkaloids. The structures of the new alkaloids were elucidated based on a comprehensive spectroscopic data analysis. The absolute configurations of 1-4 were determined by the ECD exciton chirality method and quantum ECD calculations. Protostemonine (10) and stemofoline (12) showed strong nematicidal activity against Panagrellus redivevus, with IC50 values of 0.10 and 0.46 µM, respectively.

Volvalerine A, an unprecedented N-containing sesquiterpenoid dimer derivative from Valeriana officinalis var. latifolia.

Volvalerine A (1), a novel N-containing bisesquiterpenoid derivative with a dihydroisoxazole ring, and its possible biosynthetic precursor, 1-hydroxy-1,11,11-trimethyldecahydrocyclopropane azulene-10-one (2), were isolated from the roots of Valeriana officinalis var. latifolia. Their structures and relative configurations were identified using spectroscopic data and X-ray crystallography. A plausible biosynthetic pathway for 1 is also presented.

Chemical constituents from the stems of Excoecaria acertiflia.

Six new compounds, including two diterpenoids excocarinols F and G (1 and 2, resp.), two carotane (daucane) sesquiterpenoids excoecafolinols A and B (3 and 4, resp.), one lignanoid compound, excoecanol A (5), and one simple phenol, excoecanol B (6), together with 17 known compounds, were isolated from the BuOH extract of Excoecaria acerifolia Didr. stems. Their structures were elucidated through the analysis of the spectroscopic data. The AChE-inhibitory activities of 17 compounds were evaluated and revealed that four of them possessed moderate inhibitory activities against AChE.

Two new guaiane sesquiterpenoids from Daphne holosericea (Diels) Hamaya.

Two new sesquiterpenoids with guaiane skeletons-holosericin A (1) and holosericin B (2)-were isolated from the medicinal plant Daphne holosericea (Diels) Hamawa (Thymelaeceae). Their structures were elucidated by 1D and 2D-NMR spectroscopy, as well as HR-ESI-MS data. Compounds 1 and 2 were evaluated for inhibitory activities against acetylcholinesterase and compound 2 showed a moderate activity with 31% inhibition.