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Montmorillonite clay was modified by pillaring with AlMn oxides in different Al/Mn ratios and intercalation of two kinds of N-containing polymers (i.e., chitosan (CS) and polyvinyl pyrrolidinone (PVP)) chains. The modified pillared montmorillonite clay (PM) showed a rich two-dimensional layered porous structure with tunable parameters, such as large interlayer spacing, high specific area, and large porous volume. They were then used as supports for Pd nanoparticles. As applied in coupling reactions of aryl halides with terminal alkynes, Pd@CS/AlMn-PM showed better comprehensive catalytic performance than Pd@PVP/AlMn-PM. This was mainly attributed to its higher specific area, stronger chelation to Pd species, and better solvent resistance.

The isolation and identification of an increasing number of secondary metabolites featuring unique skeletons and possessing diverse bioactivities sourced from marine microorganisms have garnered the interest of numerous natural product chemists. There has been a growing emphasis on how to cultivate microorganisms to enhance the chemical diversity of metabolites and avoid the rediscovery of known ones. Given the significance of secondary metabolites as a means of communication among microorganisms, microbial co-culture has been introduced. By mimicking the growth patterns of microbial communities in their natural habitats, the co-culture strategy is anticipated to stimulate biosynthetic gene clusters that remain dormant under traditional laboratory culture conditions, thereby inducing the production of novel secondary metabolites. Different from previous reviews mainly focusing on fermentation conditions or metabolite diversities from marine-derived co-paired strains, this review covers the marine-derived co-culture microorganisms from 2012 to 2022, and turns to a particular discussion highlighting the selection of co-paired strains for marine-derived microorganisms, especially the fermentation methods for their co-cultural apparatus, and the screening approaches for the convenient and rapid detection of novel metabolites, as these are important in the co-culture. Finally, the structural and bioactivity diversities of molecules are also discussed. The challenges and prospects of co-culture are discussed on behave of the views of the authors.

In this study, a combination of the porous carbon (PCN), montmorillonite (MMT), and TiO2 was synthesized into a composite immobilized Pd metal catalyst (TiO2-MMT/PCN@Pd) with effective synergism improvements in catalytic performance. The successful TiO2-pillaring modification for MMT, derivation of carbon from the biopolymer of chitosan, and immobilization of Pd species for the prepared TiO2-MMT/PCN@Pd0 nanocomposites were confirmed using a combined characterization with X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), N2 adsorption–desorption isotherms, high-resolution transition electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. It was shown that the combination of PCN, MMT, and TiO2 as a composite support for the stabilization of the Pd catalysts could synergistically improve the adsorption and catalytic properties. The resultant TiO2-MMT80/PCN20@Pd0 showed a high surface area of 108.9 m2/g. Furthermore, it exhibited moderate to excellent activity (59–99% yield) and high stability (recyclable 19 times) in the liquid–solid catalytic reactions, such as the Sonogashira reactions of aryl halides (I, Br) with terminal alkynes in organic solutions. The positron annihilation lifetime spectroscopy (PALS) characterization sensitively detected the development of sub-nanoscale microdefects in the catalyst after long-term recycling service. This study provided direct evidence for the formation of some larger-sized microdefects during sequential recycling, which would act as leaching channels for loaded molecules, including active Pd species.

Prostate cancer is a common cancer in elderly males. Significant progress has been made in the drug therapies for prostate cancer in recent years. However, side effects are still problems that have not been overcome by the currently used anti-prostate cancer drugs. Novel technologies can be applied to reduce or even eliminate the side effects of drugs. An aptamer may be a sequence of nucleic acids or peptides that can specifically recognize proteins or cells. Taking advantage of this feature, scientists have designed aptamer–drug delivery systems for the development of anti-prostate cancer agents. Theoretically, these aptamer–drug delivery systems can specifically recognize prostate cancer cells and then induce cell death without attacking normal cells. We collected the relevant literature in this field and found that at least nine compounds have been prepared as aptamer–drug delivery systems to evaluate their precise anti-prostate cancer effects. However, the currently studied aptamer–drug delivery systems have not yet entered the market due to defects. Here, we analyze the published data, summarize the characteristics of these delivery systems, and propose ways to promote their application, thus promoting the development of the aptamer–drug delivery systems against prostate cancer.

Laminaria japonica is widely consumed as a key food and medicine. Polysaccharides are one of the most plentiful constituents of this marine plant. In this study, several polysaccharide fractions with different charge numbers were obtained. Their physicochemical properties and anticoagulant activities were determined by chemical and instrumental methods. The chemical analysis showed that Laminaria japonica polysaccharides (LJPs) and the purified fractions LJP0, LJP04, LJP06, and LJP08 mainly consisted of mannose, glucuronic acid, galactose, and fucose in different mole ratios. LJP04 and LJP06 also contained minor amounts of xylose. The polysaccharide fractions eluted by higher concentration of NaCl solutions showed higher contents of uronic acid and sulfate group. Biological activity assays showed that LJPs LJP06 and LJP08 could obviously prolong the activated partial thromboplastin time (APTT), indicating that they had strong anticoagulant activity. Furthermore, we found that LJP06 exerted this activity by inhibiting intrinsic factor Xase with higher selectivity than other fractions, which may have negligible bleeding risk. The sulfate group may play an important role in the anticoagulant activity. In addition, the carboxyl group and surface morphology of these fractions may affect their anticoagulant activities. The results provide information for applications of L. japonica polysaccharides, especially LJP06 as anticoagulants in functional foods and therapeutic agents.

Two undescribed cytochalasins, emeriglobosins A (1) and B (2), together with nine previously reported analogues (3–11) and two known tetramic acid derivatives (12, 13) were isolated from the solid culture of Emericellopsis sp. SCSIO41202. Their structures, including the absolute configurations of their stereogenic carbons, were fully elucidated based on spectroscopic analysis and the calculated ECD. Some of the isolated compounds were evaluated for their cytotoxicity and enzyme inhibitory activity against acetylcholinesterase (AChE) in vitro. Among them, 8 showed potent AChE inhibitory activity, with an IC50 value of 1.31 μM, and 5 showed significant cytotoxicity against PC-3 cells, with an IC50 value of 2.32 μM.

Ten polyketide derivatives (1–10), including a new natural product named (E)-2,4-dihydroxy-3-methyl-6-(2-oxopent-3-en-1-yl) benzaldehyde (1), and five known diketopiperazines (11–15), were isolated from the mangrove-sediment-derived fungus Aspergillus sp. SCSIO41407. The structures of 1–15 were determined via NMR and MS spectroscopic analysis. In a variety of bioactivity screening, 3 showed weak cytotoxicity against the A549 cell line, and 2 exhibited weak antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). Compounds 3, 5, and 6 showed inhibition against acetylcholinesterase (AChE) with IC50 values of 23.9, 39.9, and 18.6 μM. Compounds 11, 12, and 14 exhibited obvious inhibitory activities of lipopolysaccharide (LPS)-induced nuclear factor-κB (NF-κB) with IC50 values of 19.2, 20.9, and 8.7 μM, and they also suppressed RANKL-induced osteoclast differentiation in bone marrow macrophages cells (BMMCs), with the concentration of 5 μM. In silico molecular docking with AChE and NF-κB p65 protein were also performed to understand the inhibitory activities, and 1, 11–14 showed obvious protein/ligand-binding effects to the NF-κB p65 protein.

This review, with 42 references, presents the fascinating area of anti-enterovirus 71 natural products over the last three decades for the first time. It covers literature published from 2005–2015 and refers to compounds isolated from biogenic sources. In total, 58 naturally-occurring anti-EV71 compounds are recorded.

Four new compounds, including two new polyketides, heterocornols M and N (1, 2), and a pair of epimers, heterocornols O and P (3, 4), were isolated from the fermentation broth of the marine sponge-derived fungus Pestalotiopsis heterocornis XWS03F09, together with three known compounds (5−7). The new chemical structures were established on the basis of a spectroscopic analysis, optical rotation, experimental and calculated electronic circular dichroism (ECD). All of the compounds (1−7) were evaluated for their cytotoxic activities, and heterocornols M-P (1−4) exhibited cytotoxicities against four human cancer cell lines with IC50 values of 20.4−94.2 μM.

Two novel altenusin-thiazole hybrids named altenusinoides A and B (1 and 2), a new benzothiazole derivative (3), and three known altenusin derivatives (4⁻6) have been obtained from the solid culture of the marine sponge-derived fungal strain, Alternaria sp. SCSIOS02F49. The structures of these new compounds were characterized by NMR, HRESIMS, and X-ray single crystal analysis. Compounds 1 and 2 possess an unusual altenusin-thiazole-fused skeleton core (6/6/5), and compound 3 represents the first benzothiazole derivative from fungi. Compounds 4 and 5 showed significant DPPH free-radical-scavenging activities with the prominent IC50 values of 10.7 ± 0.09 μM and 100.6 ± 0.025 μM, respectively. Additionally, compound 5 exhibited COX-2 inhibitory activity with an IC50 value of 9.5 ± 0.08 μM.

Two new alkaloids, fumigatosides E (1) and F (2), and a new natural product, 3, 7-diketo-cephalosporin P1 (6) along with five known compounds (3–5, 7, 8) were isolated from deep-sea derived fungal Aspergillus fumigatus SCSIO 41012. Their structures were determined by extensive spectroscopic data analysis, including 1D, 2D nuclear magnetic resonance (NMR) and mass spectrometry (MS), and comparison between the calculated and experimental electronic circular dichroism (ECD) spectra. In addition, all compounds were tested for antibacterial and antifungal inhibitory activities. Compound 1 showed significant antifungal activity against Fusarium oxysporum f. sp. momordicae with MIC at 1.56 µg/mL. Compound 4 exhibited significant higher activity against S. aureus (16,339 and 29,213) with MIC values of 1.56 and 0.78 µg/mL, respectively, and compound 2 exhibited significant activity against A. baumanii ATCC 19606 with a MIC value of 6.25 µg/mL.

A new triterpenoid saponin was isolated from Pulsatilla cernua, along with eight known triterpenoids and triterpenoid glycosides. The new compound was identified as 3-O-β-D-glucopyranosyl-(1→4)-α-L-arabinopyranosyl-bayogenin-28-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester (1) on the basis of 1D, 2D-NMR techniques, including COSY, HMBC, and HMQC correlations, MS analysis, as well as chemical methods.

A new 1,4-diazepine, callysponine (1), was isolated from a South China Sea Callyspongia sp. marine sponge, together with four known proline-based diketopiperazines: cyclo-(S-Pro-R-Leu) (2), cyclo-(S-Pro-R-Val) (3), cyclo-(S-Pro-R-Ala) (4), andcyclo-(S-Pro-R-Tyr) (5). The new structure was determined on the basis of NMR and MS analysis, and the absolute stereochemistry was defined by NOESY spectroscopy and optical rotation. The structures of the known compounds were identified by comparison of their spectroscopic data with those reported in the literature. Callysponine (1) did not inhibit the growth of HepG2 (hepatoma carcinoma cell), A549 (lung carcinoma cell), and HeLa (cervical cancer cell) cell lines.

Besides two known glycosides, a new furostanol glycoside was isolated from the Fruits of Tribulus terrestris L. The structure of the new furostanol glycoside was established as 26-O-β-D-glucopyranosyl-(25S)-5α-furostane-20(22)-en-12-one-3β, 26-diol-3-O-α-L-rhamnopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→4)]-β-D-galactopyranoside (1) on the basis of 1D and 2D-NMR techniques, including COSY, HMBC, and HMQC correlations.

One known and two new glycerolipids have been isolated from a Sarcotragus sp. marine sponge. The gross structures were established based on NMR and MS analysis.

Bis-naphtho-γ-pyrones (BNPs) are an important group of aromatic polyketides derived from fungi, and asperpyrone-type BNPs are produced primarily by Aspergillus species. The fungal strain Aspergillus niger SCSIO Jcsw6F30, isolated from a marine alga, Sargassum sp., and identified according to its morphological traits and the internal transcribed spacer (ITS) region sequence, was studied for BNPs secondary metabolisms. After HPLC/MS analysis of crude extract of the fermentation broth, 11 asperpyrone-type BNPs were obtained directly and quickly by chromatographic separation in the extract, and those isolated asperpyrone-type BNPs were structurally identified by NMR and MS analyses. All of the BNPs showed weak cytotoxicities against 10 human tumor cells (IC50 > 30 μM). However, three of them, aurasperone F (3), aurasperone C (6) and asperpyrone A (8), exhibited obvious COX-2–inhibitory activities, with the IC50 values being 11.1, 4.2, and 6.4 μM, respectively. This is the first time the COX-2–inhibitory activities of BNPs have been reported.

Two new asteltoxins named asteltoxin E (2) and F (3), and a new chromone (4), together with four known compounds were isolated from a marine sponge–derived fungus, Aspergillus sp. SCSIO XWS02F40. The structures of the compounds (1–7) were determined by the extensive 1D- and 2D-NMR spectra, and HRESIMS spectrometry. All the compounds were tested for their antiviral (H1N1 and H3N2) activity. Compounds 2 and 3 showed significant activity against H3N2 with the prominent IC50 values of 6.2 ± 0.08 and 8.9 ± 0.3 μM, respectively. In addition, compound 2 also exhibited inhibitory activity against H1N1 with an IC50 value of 3.5 ± 1.3 μM.

Two new alkaloids, fumigatosides E (1) and F (2), and a new natural product, 3, 7-diketo-cephalosporin P1 (6) along with five known compounds (3-5, 7, 8) were isolated from deep-sea derived fungal Aspergillus fumigatus SCSIO 41012. Their structures were determined by extensive spectroscopic data analysis, including 1D, 2D nuclear magnetic resonance (NMR) and mass spectrometry (MS), and comparison between the calculated and experimental electronic circular dichroism (ECD) spectra. In addition, all compounds were tested for antibacterial and antifungal inhibitory activities. Compound 1 showed significant antifungal activity against Fusarium oxysporum f. sp. momordicae with MIC at 1.56 µg/mL. Compound 4 exhibited significant higher activity against S. aureus (16,339 and 29,213) with MIC values of 1.56 and 0.78 µg/mL, respectively, and compound 2 exhibited significant activity against A. baumanii ATCC 19606 with a MIC value of 6.25 µg/mL. [ABSTRACT FROM AUTHOR]

Two new asteltoxins named asteltoxin E (2) and F (3), and a new chromone (4), together with four known compounds were isolated from a marine sponge-derived fungus, Aspergillus sp. SCSIO XWS02F40. The structures of the compounds (1-7) were determined by the extensive 1D- and 2D-NMR spectra, and HRESIMS spectrometry. All the compounds were tested for their antiviral (H1N1 and H3N2) activity. Compounds 2 and 3 showed significant activity against H3N2 with the prominent IC50 values of 6.2 ± 0.08 and 8.9 ± 0.3 µM, respectively. In addition, compound 2 also exhibited inhibitory activity against H1N1 with an IC50 value of 3.5 ±1.3 µM. [ABSTRACT FROM AUTHOR]

A new triterpenoid saponin was isolated from Pulsatilla cernua, along with eight known triterpenoids and triterpenoid glycosides. The new compound was identified as 3-O-β-D-glucopyranosyl-(1→4)-α-L-arabinopyranosyl-bayogenin-28-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester (1) on the basis of 1D, 2D-NMR techniques, including COSY, HMBC, and HMQC correlations, MS analysis, as well as chemical methods. [ABSTRACT FROM AUTHOR]

Besides two known glycosides, a new furostanol glycoside was isolated from the Fruits of Tribulus terrestris L. The structure of the new furostanol glycoside was established as 26-O-β-D-glucopyranosyl-(25S)-5α-furostane-20(22)-en-12-one-3β, 26-diol-3-O-α-L-rhamnopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→4)]-β-D-galactopyranoside (1) on the basis of 1D and 2D-NMR techniques, including COSY, HMBC, and HMQC correlations. [ABSTRACT FROM AUTHOR]

A new 1,4-diazepine, callysponine (1), was isolated from a South China Sea Callyspongia sp. marine sponge, together with four known proline-based diketopiperazines: cyclo-(S-Pro-R-Leu) (2), cyclo-(S-Pro-R-Val) (3), cyclo-(S-Pro-R-Ala) (4), and cyclo-(SPro- R-Tyr) (5). The new structure was determined on the basis of NMR and MS analysis, and the absolute stereochemistry was defined by NOESY spectroscopy and optical rotation. The structures of the known compounds were identified by comparison of their spectroscopic data with those reported in the literature. Callysponine (1) did not inhibit the growth of HepG2 (hepatoma carcinoma cell), A549 (lung carcinoma cell), and HeLa (cervical cancer cell) cell lines. [ABSTRACT FROM AUTHOR]