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Veratrazine A, a steroidal alkaloid with a unique 6/5/5 triheterocyclic scaffold as the side chain, was isolated from the roots of Veratrum stenophyllum and exhibited moderate and dose-depended anti-inflammatory activities in vitro and in vivo.

Six new (1-6) and seven known depsidones (7-13) were isolated from the culture of an ant (Monomorium chinensis)-derived fungus Spiromastix sp. MY-1. Their structures were elucidated by extensive spectroscopic analysis including high resolution MS, 1D and 2D NMR data. The new bromide depsidones were obtained through supplementing potassium bromide in the fermentation medium of Spiromastix sp. MY-1. All isolated compounds showed various bioactivities against the tested phytopathogenic bacteria. Particularly, new bromide compound 4, named spiromastixone S, exhibited the strongest activity against Xanthomonas oryzae pv. oryzae with a MIC value of 5.2 μmol·

Panax notoginseng is an important traditional medicinal plant, but the commercial value is threatened by root-rot disease caused by rhizosphere microbes and a potential health risk caused by plant arsenic (As) accumulation. Whether rhizospheric microbes isolated from P. notoginseng rhizosphere soil could impact As uptake and transport into P. notoginseng is not yet known. Among the three root-rot disease-causing pathogens Fusarium flocciferum (PG 1), Fusarium oxysporum (PG 2), and Fusarium solani (PG 3) and one root-rot disease biocontrol fungus Trichoderma koningiopsis (FC 1) and five biocontrol-exerting bacterial species Bacillus siamensis (BC 1), Delftia acidovorans (BC 2), Brevibacillus formosus (BC 3), Mortierella alpine (BC 4), and Bacillus subtilis (BC 5), one As-resistant pathogen and four biocontrol microorganisms with As-resistant ability were identified. The As-transforming ability of the identified fungi and bacteria was ranked in the order of FC 1 > PG 1 and BC 2 > BC 3 > BC 1, respectively. Then, the As-resistant biocontrol and pathogenic microbes were initiated to colonize the rhizosphere of 1-year-old P. notoginseng seedlings growing in artificially As(V)-contaminated soil to evaluate the impact of microbe inoculation on P. notoginseng As uptake and transport capacity. Concentration of As in P. notoginseng tissues decreased in the order of the sequence stem > root > leaf. Compared to treatment without colonization by microorganism, inoculation with microorganisms increased As root uptake efficiency and root As concentration, especially under treatment of inoculation by BC 2 and PG 1 + BC 2. As transport efficiency from root to stem decreased by inoculation with microorganism, especially under treatment with inoculation of BC 2 and PG 1 + BC 2. However, the impact of microorganism colonization on As stem to leaf transport efficiency was not obvious. In summary, inoculation with rhizosphere microbes may increase As accumulation in P. notoginseng root, especially when using bacteria with high As transformation ability. Therefore, it is necessary to evaluate the As transformation capacity before applying biological control microorganism to the rhizosphere of P. notoginseng.

Ten compounds (1–10) were obtained from soil-derived Penicillium cremeogriseum W1-1 with the antimicrobial guided isolation procedure. Among them, 4 presented broad-spectrum antimicrobial activities and its preliminary mechanisms were evaluated. Compound 4 showed growth inhibition on drug-resistant pathogenic strains Escherichia coli and Candida albicans with post-contact effect (PCE), changed the morphology and membrane structure, killed cells with leakage, inhibited the growth of C. albicans by eradicating biofilms. Interestingly, the fraction containing 4 presented in vivo anti-pathogenic activities in mice, indicating this indole diterpenoid alkaloid could been used as potential antimicrobial agent.

Two rearranged triterpenoids, representing new subtypes of pentacyclic triterpenoids, with unique 6/6/6/7/5 and 6/6/5/6/6/6 ring systems were isolated from Alstonia scholaris. Their structures were established by spectroscopic analysis, single-crystal X-ray diffraction, and electronic circular dichroism calculations. Both compounds exhibited potent antihyperuricemic bioactivity in vitro and in vivo.

Actinomycetes have being regarded as a treasure reservoir of various bioactive secondary metabolites and devoted many antibiotics in clinicals. Amycolatopsis sp. YNNP 00208 was isolated from a soil sample collected in Gaoligong Mountain area, Yunnan Province, China. Chemical investigation of its fermentation broth led to a new amide, baoshanmycin (1), and a new furanone derivative, 3-(1,3-dihydroxybutyl)-4-methylfuran-2(H)-one (2), together with eight known compounds, including two amides (3-4), four cyclic dipeptides (5-8), and two deoxyribonucleosides (9-10). Their structures were established on basis of the 1D- and 2D-NMR spectroscopic data, along with the HR-ESI-MS experiments. Baoshanmycin (1) showed moderate antimicrobial activities against Candida albicans, and weak activities against Staphylococcus aureus, multi-drug resistant Staphylococcus aureus, Bacillus subtilis, Listeria monocytogenes, fluconazole-resistant Candida albicans. Baoshanmycin (1) presented strong antioxidant activity and moderate anti-acetylcholinesterase activity. The other compound 3-(1,3-dihydroxybutyl)-4-methylfuran-2(H)-one (2) and the known compounds (3-10) showed moderate antioxidant activity.

Amycolatopsis sp. strain TNS106 harbors a ristomycin-biosynthetic gene cluster (asr) in its genome and produces ristomycin A. Deletion of the sole cluster-situated StrR family regulatory gene, asrR, abolished ristomycin A production and the transcription of the asr genes orf5 to orf39. The ristomycin A fermentation titer in Amycolatopsis sp. strain TNS106 was dramatically improved by overexpression of asrR and a heterologous StrR family regulatory gene, bbr, from the balhimycin-biosynthetic gene cluster (BGC) utilizing strong promoters and multiple gene copies. Ristomycin A production was improved by approximately 60-fold, resulting in a fermentation titer of 4.01 g/liter in flask culture, in one of the engineered strains. Overexpression of AsrR and Bbr upregulated transcription of tested asr biosynthetic genes, indicating that these asr genes were positively regulated by AsrR and Bbr. However, only the promoter region of the asrR operon and the intergenic region upstream of orf12 were bound by AsrR and Bbr in gel retardation assays, suggesting that AsrR and Bbr directly regulated the asrR operon and probably orf12 to orf14 but no other asr biosynthetic genes. Further assays with synthetic short probes showed that AsrR and Bbr specifically bound not only probes containing the canonical inverted repeats but also a probe with only one 7-bp element of the inverted repeats in its native context. AsrR and Bbr have an N-terminal ParB-like domain and a central winged helix-turn-helix DNA-binding domain. Site-directed mutations indicated that the N-terminal ParB-like domain was involved in activation of ristomycin A biosynthesis and did not affect the DNA-binding activity of AsrR and Bbr. IMPORTANCE This study showed that overexpression of either a native StrR family regulator (AsrR) or a heterologous StrR family regulator (Bbr) dramatically improved ristomycin A production by increasing the transcription of biosynthetic genes directly or indirectly. The conserved ParB-like domain of AsrR and Bbr was demonstrated to be involved in the regulation of asr BGC expression. These findings provide new insights into the mechanism of StrR family regulators in the regulation of glycopeptide antibiotic biosynthesis. Furthermore, the regulator overexpression plasmids constructed in this study could serve as valuable tools for strain improvement and genome mining for new glycopeptide antibiotics. In addition, ristomycin A is a type III glycopeptide antibiotic clinically used as a diagnostic reagent due to its side effects. The overproduction strains engineered in this study are ideal materials for industrial production of ristomycin A.

Two distinctive alkaloids with 6/6/6/5/6/6 fused rings, in which a previously unidentified linkage of C-12/23 generates a rigid skeleton, resulting in a new subtype of steroidal alkaloid, were isolated from Veratrum grandiflorum. Compounds 1 and 2 showed potent analgesic effects in vivo, superior to the well-known analgesic, pethidine (Dolantin), likely by inhibiting CaV2.2 voltage-gated calcium channels.

Three new phenazine metabolites, strepphenazine A-C (1-3), along with a known compound baraphenazine E 4 were isolated from the culture broth of a Streptomyces strain YIM PH20095. The structures were elucidated based on the spectral data. Compounds 1-4 showed different antifungal activity against Fusarium oxysporum, Plectosphaerella cucumerina, Alternaria panax, and Phoma herbarum, which caused root-rot disease of Panax notoginseng with minimal inhibitory concentrations (MICs) of 16-64 μg/mL; compared with compound 4, compounds 1-3 showed better antifungal activity against some of these pathogenic fungi with MICs of 16-32 μg/mL, while compound 4 showed antifungal activity against F. oxysporum, P. cucumerina, and A. panax with the same MICs of 64 μg/mL. Thus, strain YIM PH20095 provides new sources for the development of biological control agents to prevent the infection of pathogenic fungi of P. notoginseng.

Acyltransferase (AT)-less type I polyketide synthases (PKSs) produce complex natural products due to the presence of many unique tailoring enzymes. The 3-hydroxy-3-methylglutaryl coenzyme A synthases (HCSs) are responsible for β-alkylation of the growing polyketide intermediates in AT-less type I PKSs. In this study, we discovered a large group of HCSs, closely associated with the characterized and orphan AT-less type I PKSs through in silico genome mining, sequence and genome neighbourhood network analyses. Using HCS-based probes, the survey of 1207 in-house strains and 18 soil samples from different geographic locations revealed the vast diversity of HCS-containing AT-less type I PKSs. The presence of HCSs in many AT-less type I PKSs suggests their co-evolutionary relationship. This study provides a new probe to study the abundance and diversity of AT-less type I PKSs in the environment and microbial strain collections. Our study should inspire future efforts to discover new polyketide natural products from AT-less type I PKSs.

Lymphatic filariasis and onchocerciasis diseases caused by filarial parasite infections can lead to profound disability and affect millions of people worldwide. Standard mass drug administration campaigns require repetitive delivery of anthelmintics for years to temporarily block parasite transmission but do not cure infection because long-lived adult worms survive the treatment. Depletion of the endosymbiont Wolbachia, present in most filarial nematode species, results in death of adult worms and therefore represents a promising target for the treatment of filariasis. Here, we used a high-content imaging assay to screen the pure compounds collection of the natural products library at The Scripps Research Institute for anti- Wolbachia activity, leading to the identification of kirromycin B (1) as a lead candidate. Two additional congeners, kirromycin (2) and kirromycin C (3), were isolated and characterized from the same producing strain Streptomyces sp. CB00686. All three kirromycin congeners depleted Wolbachia in LDW1 Drosophila cells in vitro with half-maximal inhibitory concentrations (IC

In recent years, the T-cell therapy and immune checkpoint inhibitors toward CTLA-4 and PD-1/PD-L1 axis antibody therapy have acquired encouraging success. However, most of patients were still not benefited with lots of troubles, such as low penetration of tissues/cells, strong immunogenicity and cytokine release syndrome, and long manufacturing process and expensive costs. By contrast, the immune-modulating small molecules possessed natural advantages to overcome these obstacles and might achieve greater success.Exploring the potent immune-modulating natural small molecules and revealing what kinds of molecules or structures with the immunomodulatory activity against cancers.A novel non-cytotoxic T-cell immunomodulating screening model was used to identify the cytotoxic/selective/immunomodulatory bioactivity for 148 natural steroidal saponins. The structure-activity relationships (SARs) research was used to reveal the key groups for immunomodulation/cytotoxicity/selectivity. The negative selection was used to isolate and purify the T-cell. The cell viability assay was used to measure the anti-cancer effect in vitro. The ELISA assay was used to detect the cytokines for IL-1β, IL-6, TNF-α, IFN-γ, IL-12, perforin and granzyme B (GZMB). The western blotting assay was used to research the immunomodulatory mechanism. The siRNA knockdown was used to generate the IFN-γ resistant melanoma cells. The NOG immune-deficient mice were used to evaluate the anti-tumor efficacy in vivo. The peripheral blood samples from 10 cancer patients were used to detect the broad population anti-tumor efficacy.It was reported that the correlation among structures and immunomodulation/ cytotoxicity/selectivity, in which opening ring-F with 26-O-glucopyranosyl, disaccharide and trisaccharide chains at C-3, steric hindrance and polarity of C-22 were key immunomodulatory groups. Moreover, taccaoside A was identified as the most potent candidate against cancer cells, including non-small cell lung cancer, triple negative breast cancer, and the IFN-γ resistant melanoma, partly through enhancing T lymphocyte mTORC1-Blimp-1 signal to secrete GZMB. Besides, 10 patients derived T-cell also would be modulated against cancer cells in vitro. Moreover, the overall survival was great extended (140 days vs 93 days) with nearly 100% tumor burden disappearance (0 mmThis work demonstrated one possibility for this concerned purpose, and identified a potent immune-modulating natural molecule taccaoside A, which might contribute to cancer immunotherapy in future.

A new compound named koninginin W (1) and four known polyketides (2-5) were isolated from endophytic fungus Trichoderma koningiopsis YIM PH30002 of Panax notoginseng. The structures of 1 - 5, including absolute configuration of 1, were elucidated on the detailed analysis of the HR-ESI-MS, 1D and 2D NMR, and X-ray crystallographic data. Koninginin W (1) presented weak antibacterial activity against Escherichia coli, Bacillus subtilis and Salmonella typhimurium.

"Li-Lu", the roots and rhizomes of Veratrum grandiflorum (Melianthiaceae), has been historically used as a traditional folk medicine for the treatment of wrist pain, fractures, sores, and inflammation in Yunnan Province, China. However, the anti-inflammatory and analgesic studies of this plant have seldom reported.To evaluate the anti-inflammatory and analgesic properties related to the traditional usage of V. grandiflorum both in vitro and in vivo, and further explore the accurate bioactive compounds from the medicinal plant.Phytochemical investigation was carried out by chromatographic methods and their structures were established based on extensive spectra and comparison with corresponding data in the reported literatures. Anti-inflammatory activities were assessed by the suppression of lipopolysaccharide-activated inflammatory mediators in RAW 264.7 macrophage cells in vitro. Furthermore, anti-inflammatory and analgesic effects were evaluated based on carrageenan-induced paw edema and acetic acid-stimulated writhing in mice.The methanol extract (ME) of V. grandiflorum significantly alleviated the paw edema caused by carrageenan and the writhing numbers induced by acetic acid. Subsequent phytochemical investigation led to isolated of 21 steroidal alkaloids, including seven new compounds, veragranines C-I (1-7). Anti-inflammatory test indicated that steroidal alkaloids could decrease the expression of cyclooxygenase-2 (COX-2), interleukin-1β (IL-1β), and tumor necrosis factor α (TNF-α) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells at a concentration of 5.0 μg/ml in vitro, comparable to DXM. Moreover, five new steroidal alkaloids (2, 4, 5, 6, and 7) and two major steroidal alkaloids (9 and 13) significantly decreased the numbers of writhing in mice at the doses of 0.5 and/or 1.0 mg/kg (p 0.01/0.05), roughly comparable to Dolantin™ at 10.0 mg/kg.The investigation supported the traditional use of V. grandiflorum and provided new steroidal alkaloids as potent analgesic agents.

Endophytic fungi play important roles for host's stress tolerance including invasion by pathogenic microbes. Small molecules are common weapons in the microbe-microbe interactions. Panax notoginseng is a widely used traditional Chinese medicinal plant and harbors many endophytes, some exert functions against pathogens. Here, we report six new compounds named myrothins A-F (1-6) produced by Myrothecium sp. BS-31, an endophyte isolated from P. notoginseng, and their antifungal activities against pathogenic fungi causing host root-rot disease. Their structures were elucidated with analysis of spectroscopic data including 1D and 2D NMR, HR-ESI-MS. Myrothins B (2) and E (5) showed the weak activity against Fusarium oxysporum and Phoma herbarum, and myrothins F (6) showed weak activity against F. oxysporum.

Introduction The structural annotation of target relies on high-resolution mass spectrometry (HRMS) information resulting in dubious identities in most cases. The accurate annotation of isomeric structures is still challenging to be confirmed with significant bottleneck. Objective This study focused on the improvement of structural annotation of candidate structures via four pairs of isomeric flavanone-7-O-diglucosides and their basic flavanone aglycones commonly detected in citrus products. Method An integrated liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS) approach merging retention time, accurate mass, tandem mass spectrometry (MS/MS) information (diagnostic ions), ion ratio at selected collision energy was established successfully. Results Feasibility of this approach was validated confidently in biological samples with relative standard deviation (RSD) of ion ratio range from 3.91 to 12.28%. Differences of fragmentation patterns of citrus flavanones were illustrated reasonably. MS/MS fragments of (S)-hesperetin and (S)-isosakuranetin were complicated and showed typical radical ion [1,2 A - H]•- (m/z 164) in negative ESI mode due to the methoxyl group on B-ring, which showed huge difference with (R)-hesperetin and (R)-isosakuranetin. Conclusion This study integrated multiple levels to boost the confidence of structural annotation relied on LC-HRMS, and provided important values in practice for precise identification of citrus flavanones in biological matrices.

The whole plant of Clerodendranthus spicatus (Thunb.) is one of popular functional food in south of China, named as "kidney tea" and used to ameliorate renal inflammation. In order to verify this potential function and explore the accurate compounds responsible for inflammation, the ethanol extract, fractions, and subfractions of this plant were prepared to evaluate anti-inflammation effect on xylene-induced acute inflammatory mice model, and the results indicated that two subfractions from EtOAc fraction show potential activities. Subsequent bioassay-guided isolation of the bioactive subfractions led to isolation of 25 compounds. Among them, compounds 2, 4, 5, 9-11, 13, 16, 17, and 20-22 inhibited the productions of pro-inflammation factors TNF-α, IL-1β, and IL-8 in lipopolysaccharide (LPS) -induced renal epithelia (HK-2) cells, respectively. Further anti-inflammation evaluation in vivo indicated that the major bioactive compounds 1, 2, 5-7, 17, 21, and 22 from C. spicatus were even better than aspirin. PRACTICAL APPLICATIONS: C. spicatus as a healthy tea has been available in the Chinese market and as a medicine for various disorders such as nephritis, rheumatism, inflammation, gout, and diabetes. Previous pharmacological investigation of the plant revealed the potential anti-inflammatory activities, but the material basis of anti-inflammatory activity remains to be elucidated. In our study, the anti-inflammatory fractions and compounds were obtained by the bioassay-guide isolation and the results showed that the highly oxygenated diterpenoids were major anti-inflammatory compounds, in which 1, 2, 5-7, 17, 21, and 22 were even better than aspirin. This information supported kidney tea as a functional food for treatment of renal inflammation reasonably and may add a new dimension to biological activity of this plant in the field of agriculture as a functional food were cultivated.

Glioblastoma multiform (GBM) is the highly aggressive brain tumor with poor prognosis. Glioma stem cells (GSCs), small population of cancer cells that exist in GBM tissues, resistant to chemotherapy and radiotherapy and usually driving GBM recurrence, have been developed as effective therapeutic target. Steroidal saponins are one of important resources for anti-tumor agent and may be benefited to selectively clear GSCs. In this report, total of 97 natural steroidal saponins were investigated the relationship among structures/cytotoxicity/selectivity against GSCs, glioma cell lines and human untransformed cells, and revealed that tribulosaponin A was the most potent compound. Further investigation suggested that tribulosaponin A up-regulated the expression of NCF1 and NOX1 to accumulate ROS for triggering apoptosis in GSCs, but not in untransformed cells, and it was further supported by the assay that N-acetyl-l-cysteine (NAC) clearing ROS delayed GSCs apoptosis. Besides, tribulosaponin A damaged GSCs recapturing tumor spheres formation.

Actinomycete strain YIM PH20520, isolated from the rhizosphere soil sample of Panax notoginseng collected in Wenshang, Yunnan Province, China, exhibited antifungal activity against root-rot pathogens of the Panax notoginseng. The structures of bioactive molecules, isolated from the ethyl acetate extract of the fermentation broth of the strain, were identified as echinosporin (1) and 7-deoxyechinosporin (2) based on extensive spectroscopic analyses. 1 exhibited antifungal activity against four tested root-rot pathogens of Panax notoginseng include Fusarium oxysporum, Fusarium solani, Alternaria panax, and Phoma herbarum with the MIC value at 64, 64, 32, and 64 μg/mL, respectively. 2 exhibited antifungal activities against F. oxysporum, F. solani, A. panax, and P. herbarum with the MIC value at 128, 128, 64, and 128 μg/mL, respectively. Based on the phylogenetic analyses, the closest phylogenetic relative of strain YIM PH20520 is Amycolatopsis speibonae JS72T (97.69%), so strain YIM PH20520 was identified as Amycolatopsis strain. To the best of our knowledge, this is the first report of echinosporin antibiotics isolated from Amycolatopsis strain besides Streptomyces strain and their antifungal activity against four tested root-rot pathogens of the Panax notoginseng. The results provide a reliable evidence for the following related biosynthetic investigations on Amycolatopsis strain YIM PH20520 due to echinosporins antibiotics’ unique tricyclic acetal-lactone structures.

A high-content imaging assay was used to screen the fraction collection of the Natural Product Library at The Scripps Research Institute for inhibitors of Cryptosporidium parvum. A chemical investigation of one strain, Streptomyces sp. CB01388, resulted in the isolation of six herbicidins (1-6), one of which is new (herbicidin L, 1). Five of the six herbicidins (1-3, 5, 6) showed moderate inhibitory activity against C. parvum, with 1 and 6 comparable to the FDA-approved drug nitazoxanide, and 2-6 showed no toxicity to the host HCT-8 cells and human HEK293T and HepG2 cells. These findings highlight the herbicidin scaffold for anti- Cryptosporidium drug development.

Two new aspinotriol derivatives (1-2) determined as melleusin A (1), B (2) and other seven known compounds were isolated from a soil-borne fungus Aspergillus melleus. The configurations of 1, and 2 were determined by their analogues, aspilactonol B, C isolated previous in Aspergillus. Mellein (8) showed broad antibiotic activity against the test pathogens. Aspinonene, aspinotriols A and B can be used as the marker molecule in chemotaxonomy of Aspergillus.

Eleven new compounds with streptazolin- and obscurolide-type skeletons were isolated from soil-derived Streptomyces alboniger obtained from Tibet, China. Two types of unprecedented skeletons of obscurolide dimer and an obscurolide-type compound with an aromatic polyketide of pentanone substituted at the benzene ring were determined by spectral data analysis. Compound 11 was the first evidence of two nitrogens in streptazolin-type structures. Compound 1 indicated an inhibitory effect on nitric oxide production in LPS-activated macrophages with an inhibition ratio of 51.7% at 50 μM, and on anticoagulant activity on platelet activating factor (PAF)-induced platelet aggregation with an inhibition ratio of 26.0 ± 9.1% at 200 μg mL−1. 11 had anti-acetylcholinesterase activity with an inhibition ratio of 27.2% at a concentration of 50 μM. Mechanistic aspects of the non-enzymatic reaction as well as a more detailed picture of the biosynthetic relationships of the streptazolin- and obscurolide-type metabolites are described. Acidic and basic conditions can inhibit the growth of Streptomyces, and γ-butyrolactones were found to be hormones controlling antibiotic production in Streptomyces. In the pH fermentation tests, acylation of γ-butyrolactones was successfully used to explain the mechanism of influence on the growth of Streptomyces.

A new natural mycotoxin was isolated from the fermentation broth of Trichoderma sp. Jing-8 and the structure was determined as alternariol 1′-hydroxy-9-methyl ether (1), together with twelve known compounds. The structures were elucidated on the basis of their 1D, 2D NMR spectra and mass spectrometric data. Compounds 1, 8 and 9 indicated inhibitions against germination of the seeds of cabbage with MICs 1 showed the antibacterial activity against Bacillus subtilis and Staphylococcus aureus with MICs at 64 μg/mL. Compound 1 and 3 showed significant DPPH radical-scavenging activities with IC50 at 12 μg/mL, respectively. The OH at C-1′ in compound 1 decreased the cytotoxicity of these mycotoxins. A primary structure–activity relationship about the alternariol derivatives was discussed. Compounds 2–7 and 8 were the first time to be isolated from the Trichoderma.

Three new phenazine metabolites, strepphenazine A-C (

Strain YIM PH21724T was isolated from the rhizosphere of Panax notoginseng. Phylogenetic analyses based on 16S rRNA gene sequences showed that the strain exhibits close phylogenetic relatedness to Nocardia kroppenstedtii N1286T (97.70%), Nocardia farcinica NCTC 11134T (97.67%) and Nocardia puris DSM 44599T (97.40%). The menaquinones were identified as MK-9 (H4), MK-8 (H4, ω-cyclo) and MK-8 (H4), and the major fatty acids (> 10%) were identified as C16:0, C18:1 ω9c and C18:0 10-methyl. The polar lipids were found to be composed of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannosides and an unidentified lipid. The G + C content of the genomic DNA was determined to be 67.01 mol%. The phenotypic, chemotaxonomic, phylogenetic and genomic results clearly show strain YIM PH21724T should be classified in the genus Nocardia and represents a novel species, for which the name Nocardia panacis sp. nov. is proposed. The type strain is YIM PH21724T (= DSM 105904T = KCTC 49030T = CCTCC AA 2017043T).

Phytochemical investigation of the alkaloidal extract of the roots of Toddalia asiatica led to the isolation of a new seco-benzophenanthridine alkaloid (1) and twelve known alkaloids (2–13). The new structure was elucidated by means of spectroscopic analysis, and the known alkaloids were identified by comparison with the literature. Among these alkaloids, 1 and 5–7 were reported from the genus Toddalia for the first time. The distribution of the isolated alkaloids at genus/family level was presented via network analysis and their chemotaxonomic significance was also discussed.

A new meroterpenoid preaustinoid D ( 1 ) and a new neogrifolin derivative dihydroxyneogrifolic acid ( 2 ), together with other five previously reported meroterpenoids ( 3 - 7 ) were isolated from the endophytic fungus Penicillium sp. T2-8 associated with Gastrodia elata . The structures were elucidated on the basis of spectroscopic data analyses. It was the first time that neogrifolin and its derivatives were isolated from microorganism. Some of these meroterpenoids exhibited obvious antimicrobial activities in the microdilution antimicrobial assays.

The rare anishidiol and five new isochromans, including three novel dimers with unprecedented skeletons, were isolated from Stachybotrys sp. PH30583. Their structures were determined by spectral analyses. The bioactivities of these compounds were also investigated. The dimers (6–10) inhibited acetylcholinesterase at 50 µM, but the monomers did not. To investigate the biogenesis of the novel dimers, a time-course investigation of metabolite production was undertaken.

Isofuranonaphthoquinones (IFQs) and Isoindolequinones (IIQs) comprise a small family of natural products, with the latter ones are especially uncommon in nature. Here we report the discovery of seven new IFQs, IFQ A-G (1-7), and three new IIQs, IIQ A-C (8-10), along with the known anthraquinone desoxyerythrolaccin (11), from Streptomyces sp. CB01883, expanding the chemical diversity of this family of natural products. The structures of these natural products were established on the basis of their HR-ESI-MS and nuclear magnetic resonance (NMR) spectroscopic data. All compounds were assessed for antibacterial activity, with 11 and 1, 5-7 exhibiting moderate and weak activities, respectively, against several Gram-positive bacteria tested. Bioinformatics analysis of the Streptomyces sp. CB01883 genome revealed the ifq gene cluster that showed identical genetic organization, with high-sequence identity, to the ifn gene cluster recently cloned from Streptomyces sp. RI-77 and confirmed to encode the biosynthesis of two IFQs, JBIR-76 and JBIR-77. Co-isolation of IFQs with IIQs from Streptomyces sp. CB01883 and facile chemical transformation of selected IFQs to IIQs, as exemplified by 1 to 9, together with the finding of the ifq cluster that most likely only encodes IFQ biosynthesis, support the proposal that IIQs may be derived nonenzymatically from IFQs in the presence of an amine.

Aporphine alkaloids were transformed into the corresponding stereospecific 4 R -hydroxyaporphine alkaloids through the solid-state fermentation of Stephania epigaea with Clonostachys rogersoniana . This process was validated by both solid- and liquid-state fermentations with aporphine alkaloids as substrates. Cytochrome P450 enzymes were confirmed to participate in the catalysis of this biotransformation. 4 R -Hydroxyaporphine alkaloids exhibit the same levels of acetylcholinesterase (AChE) inhibitory and cytotoxic activities as aporphine alkaloids and are considerably more water soluble than aporphine alkaloids, indicating their potential as water-soluble AChE inhibitors and antitumor agents. This paper suggests that C. rogersoniana fermentation can facilitate a novel biotransformation of aporphine alkaloids in S. epigaea to 4 R -hydroxyaporphine alkaloids.