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Five previously undescribed epoxy octa-hydronaphthalene polyketides, altereporenes A–E (1–5) were isolated from rice culture of the endophytic fungus Alternaria sp. YUD20002 derived from the tubers of Solanum tuberosum.

α-Terpineol (1), the main volatile constituent in some traditional Chinese medicines, has been reported to be metabolized to 4R-oleuropeic acid by the larvae of common cutworms. The present study verified that α-terpineol could be converted to 4R-oleuropeic acid (2) and (1S,2R,4R)-p-menthane-1,2,8-triol (3) by Alternaria alternata fermentation. Using shortened fermentation times, 7-hydroxy-α-terpineol (2a) was identified as an oxidative intermediate, which was consistent with the hypothesis put forward by previous studies. Cytochrome P450 enzymes were also confirmed to catalyze this biotransformation. This is the first study on the biotransformation of α-terpineol by microbial fermentation.

Species of the genus Delphinium have been extensively used for different purposes by various civilizations worldwide since antiquity. Phytochemical investigations on Delphinium plants in the last four decades (1980–2019) have afforded a total of 453 new compounds, most of which are diterpenoid alkaloids. These constituents are of great research significance due to their novel structures and broad bioactivities. This review addresses, for the first time, the chemical constituents of Delphinium plants and the biological properties of these compounds to facilitate future research.

For centuries, species of the genus Consolida (Ranunculaceae) have been extensively utilized for their extremely high ornamental and medicinal values. Phytochemical investigations of Consolida species have revealed the presence of multiple active ingredients, including diterpenoid alkaloids, flavonoids, phenolic acids, phytosterols, fatty acids, and volatile constituents. These chemical constituents are of great research significance due to their novel structures and broad biological activities. This review addresses, for the first time, the chemical constituents of Consolida plants and the biological activities of these compounds to facilitate future research.

Six new C12 polyketides, phomretones A–F (1–6), were isolated from the co-culture of Armillaria sp. and the endophytic fungus Phoma sp. YUD17001 associated with Gastrodia elata. Neither fungus produced these compounds when cultured alone. The structures of 1–6 were established on the basis of comprehensive spectroscopic analyses, while their absolute configurations were determined by the comparsion of experimental and calculated ECD spectra. Compounds 2–4 are diastereoisomers of each other and featured high levels of stereoisomerization and oxidation.

Emerging evidence reveals that lncRNAs play important roles in various pathological processes, but precious little indicates their regulatory role in neuropathic pain. In this study, we performed unbiased whole transcriptome profiling in dorsal root ganglions (DRGs) from mice with sham operation and mice with chronic constriction injury (CCI). Gm5820 was one of the most downregulated RNA transcripts in CCI neuropathic pain model mice. Then, a pcDNA-Gm5820 expression vector was constructed and administered into CCI mice through intrathecal injection. The results showed that upregulation of Gm5820 alleviated mouse mechanical allodynia and thermal/cold hyperalgesia, and reduced the accumulation of inflammatory cytokines and ROS in the DRG tissue. Moreover, different concentrations of pcDNA-Gm5820 expression vector and Gm5820 siRNA were respectively transfected into primary DRG neurons from 4th to 6th lumbar vertebra (L4–L6). We found that Gm5820 overexpression improved cell viability and migration, and reduced the production of ROS, LDH and IL-1β. In contrast, Gm5820 knockdown had the opposite effects. Furthermore, RNA pull-down assays with FGF1 and Gm5820 cDNA probes both demonstrated that FGF1 mRNA and Gm5820 directly bound to each other. Moreover, Gm5820 negatively regulated the stability of FGF1 mRNA. Gm5820 suppressed the expression of FGF1 at the post-transcriptional level and negatively regulated the activation of ERK1/2-mediated STAT3, a critical contributor in neuropathic pain. In conclusion, Gm5820 directly binds to FGF1 mRNA and suppresses FGF1 expression at the posttranscriptional level, it functions as a negative regulator in the activation of the ERK/STAT3 pathway, and upregulation of Gm5820 alleviates neuropathic pain in CCI mice.

Species of the genus Aconitum are widely distributed in the north temperate region and have been used in traditional medicine since antiquity due to their biological activities. Phytochemical investigations of Aconitum species have revealed the presence of multiple active ingredients, including flavonoids, phenylpropanoids, phenolics and acids, terpenoids, and polysaccharides in addition to their diterpenoid alkaloids. These non-alkaloidal constituents show great research significance for their novel structures, broad bioactivities, and chemotaxonomical significance. This review addresses, for the first time, the non-alkaloidal constituents and their biological properties and their taxonomic significance for Aconitum plants to facilitate future research.

Six new C

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.

Eleven new polyketones named diaporthsins A–K (1–11) were isolated from the fermentation of Diaporthe sp. JC-J7. The chemical structures of compounds (1–11) were elucidated by spectroscopic methods including HRESIMS, 2DNMR, NMR and chemical methods. Compound 11 features an unusual acyclic polyketone–phenolic polyketone hybrid structure that integrates the characteristics of different fungal metabolites (cytosporone and multiplolide). Compound 3 was the only C12-polyketone obtained in this research. These new polyketones showed inhibitory activity on triglycerides (TG) in steatosis hepatocyte L-02 cells. Among them, compound 5 and (4E)-6,7,9-trihydroxydec-4-enoic acid displayed inhibitory activities on TG in steatotic L-02 cells with inhibition ratios of 26% and 21% at concentration of 5 μg mL−1; also, inhibition ratios of 8-O-acetylmultiplolide A and phomopsisporone A at concentration of 5 μg mL−1 were calculated to be about 24% and 16%, respectively, which were equivalent to the antihyperlipidemic activity of lovastatin. The preliminary structure–activity relationship indicated that acetyl at C-8 can increase the antihyperlipidemic activity of multiplolide A and the glycol ester and hydroxyl at C-6 can also increase the corresponding activity of diaporthsin B.

Coordination polymer nanoparticles (CPNs) formed by self-assembly of metal ions (or clusters) and organic bridging ligands through coordination bonds provide a unique platform for designing multifunctional nanoparticles. In this work, we report a ratiometric fluorescent probe for Zn2+ based on CPNs, which were prepared from AIE fluorophore HDBB molecules with metal ions. The CPNs are composed of HDBB molecules with Tb3+ (named Tb-HDBB-CPNs) which displayed a matrix coordination-induced emission peak at a wavelength of 590 nm, while CPNs formed by HDBB molecules and Zn2+ (named Zn-HDBB-CPNs) showed a distinctive fluorescent property with a blue emission peak wavelength of 470 nm. Based on the cation exchange process of Tb-HDBB-CPNs with Zn2+, a highly selective ratiometric fluorescent probe for the determination of Zn2+ in aqueous solution was developed with a linear range from 0.1 to 60 μM and a detection limit of 50 nM. Our approach using AIE molecules as organic ligands for the construction of CPNs paves a way toward AIE functionalized materials with ratiometric fluorescence response and will find wide applications in chemical sensing.

A simple and practical thio-Michael addition of α,β-unsaturated amides catalyzed by Nmm-based ionic liquids with a 1,2-propanediol group has been developed. All the α,β-unsaturated amides without substituents at the carbon end could smoothly react with sulfur-nucleophiles in water. Meanwhile for thio-Michael addition of α,β-unsaturated amides with substituents at the carbon end, the relevant product could also be obtained successfully under solvent-free conditions at 55 °C. Furthermore, the IL-catalyst is recyclable and applicable for gram-scale synthesis.

Illigera aromatica, a medicinal liana, was fermented with Clonostachys rogersoniana. Two novel menthane-type monoterpenoid dimers, dimericilligerates E (1) and F (2) were isolated from the fermented material. Their structures were identified by 1D/2D NMR, electric circular dichroism, derivatization, and Mosher's method. A novel elimination reaction that formed a benzene ring from a menthane moiety afforded derivative 1a, which possesses more resolved NMR signals than the dimeric monoterpenoid, dimericilligerate E (1). The determination of 1a verified the estimation of 1. Compounds 1 and 2 showed potent cytotoxic activities; especially, 1 possessed significant activities against the liver hepatocellular carcinoma cell line (SMMC-7721) with an IC50 value of 3.89 ± 0.23 μM. Three novel precursors, dimericilligerates A–C (3–5), were identified by HPLC-MS and isolated from the original I. aromatica. This paper presents a novel class of monoterpenoid dimers and suggests that C. rogersoniana-fermented I. aromatica is effective to produce cytotoxic dimeric monoterpenoids from inactive original materials.

We report the advantageous properties of inorganic copper(I) thiocyanate (CuSCN) as a solution-processable hole injection material in quantum dot-based light-emitting diodes (QLEDs). CuSCN, with its high work function, it decreases the turn-on voltage (Vth) by 0.8 volt to 3.4 V as compared with devices based on the most-widely used poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) (Vth = 4.2 V). As a transparent, highly stable and low cost commercial material, CuSCN acting as the hole injection layer (HIL) gives the QLED better Vth, and comparable performance to PEDOT:PSS-based QLED for other parameters including maximum luminance and external quantum efficiency. The decreased Vth can improve the power efficiency and is a necessary step in meeting market demand. The successful demonstration of the solution-processed inorganic HIL using simple and low temperature processing routes provide guidelines and prospects for the development of reliable all-inorganic and tandem QLEDs and possible commercial applications at a large scale.

A domino reaction of phthalhydrazide and vinylketone in the presence of phosphotungstic acid was successfully established, and 3D turbine-type tetrasubstituted 1H-indazolo[1,2-b]phthalazinedione derivatives were conveniently obtained with moderate to excellent yields (up to 95%). The highly efficient catalytic system exhibited broad substrate scopes under mild conditions. A 78% yield of the desired product was obtained when the reaction was conducted on a multi-gram scale.

α-Terpineol (1), the main volatile constituent in some traditional Chinese medicines, has been reported to be metabolized to 4

A dual-emission pH-sensitive fluorescent probe was developed, which displays green fluorescence in alkaline after deprotonation, while orange emission in acid at aggregated state. This novel probe allows the specific light-on in acidic lysosomes of cancer cells and tumors in nude mice, which indicates its potential application in cancer diagnosis.

Eleven new polyketones named diaporthsins A-K (1-11) were isolated from the fermentation of

Fluorescence of DNA-templated silver nanoclusters can be enhanced by more than 100-fold by placing the nanoclusters in proximity to guanine-rich DNA sequences after hybridization. We found that the fluorescence of the guanine-enhanced silver nanoclusters is not increased with the guanine-rich DNA sequence closer to the silver nanoclusters. By studying the different numbers of mismatches in the linker sequences, we found that the presence of a single-nucleotide mismatch in the linker increases fluorescence more than the complementary nucleotide. Further study indicated the mismatch position of the linker sequence also affects the fluorescence of the hybridized DNA-Ag NCs. The evidence reported here indicated that the mismatch of the linker sequence affects the fluorescence enhancement of guanine-enhanced silver nanoclusters. We also found that DNA-Ag NCs is an excellent fluorescence sensor for cyanide, as cyanide effectively quenches the fluorescence of NCs at a very low concentration with high selectivity. Cyanide in the range from 0.10 μM to 0.35 μM could be linearly detected, with a detection limit of 25.6 nM.

Scalable patterning of photonic crystals is critical in building advanced photonic devices. In this communication, we applied solvent-assisted imprinting technique to define the patterns of pre-formed colloidal photonic crystal (CPC) films. The minute solvent within the PDMS stamp along with the conformal pressure partially melts and relocates the polymers, thereby forming large-scale micropatterns in the CPC.

In order to improve the stability of micelles and decrease the burst release of loaded drugs, photo-cross-linked micelles were prepared via photodimerization of the coumarin moiety on amphiphilic poly(ether amine) (PEAC). The structures of the obtained monomer and polymers were confirmed by Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-vis), 1H NMR and 13C NMR (Nuclear Magnetic Resonance, NMR). PEAC could self-assemble into micelles by directly dispersing in water with a hydrophobic coumarin core and a hydrophilic poly(ethylene glycol) (PEG) shell. The photo-cross-linking process of the PEAC micelles was monitored by UV-vis spectroscopy. The morphology and size distribution of the micelles was characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS). Anticancer drug doxorubicin (DOX) was loaded into the micelles during the process of micelle formation. Photo-cross-linked micelles showed slower drug release and cellular uptake in comparison with the uncross-linked micelles. And both DOX-loaded micelles displayed pH-sensitive release behaviours. Moreover, the DOX-loaded photo-cross-linked micelles exhibit comparative anticancer efficacy as free DOX. These results indicated that photo-cross-linked PEAC micelles can be used as potential drug carriers for intelligent drug delivery.