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Six new β-resorcylic acid derivatives (1–5 and 7) were isolated from a halophyte-associated fungus, Colletotrichum gloeosporioides JS0419, together with four previously reported β-resorcylic acid lactones (RALs). The relative and absolute stereochemistry of 1 was completely established by a combination of spectroscopic data and chemical reactions. The structures of the isolated compounds were elucidated by analysis of HRMS and NMR data. Notably, compounds 1–3 had a β-resorcylic acid harboring a long unesterified aliphatic side chain, whereas the long aliphatic chains were esterified to form macrolactones in 4–9. Among the isolated compounds, monocillin I and radicicol showed potent antifungal activities against Cryptococcus neoformans, comparable to clinically available antifungal agents and radicicol showed weak antifungal activity against Candida albicans. These findings provide insight into the chemical diversity of fungal RAL-type compounds and their pharmacological potential. [ABSTRACT FROM AUTHOR]

β-Resorcylic acid lactones (RALs) are one of the major polyketides produced by fungi, and some of them have a diverse array of biological activities. Most RALs feature a 14-membered macrocyclic ring fused to β-resorcylic acid (2,4-dihydroxybenzoic acid). In this review, more than 100 RAL-type of compounds are structurally classified into three groups; 14-membered RALs with 17R configuration, 14-membered RALs with 17S configuration, and benzopyranones/benzofuranones, and they are reviewed comprehensively in terms of chemistry, biological activities, and biosynthetic pathways. [ABSTRACT FROM AUTHOR]

Sparassis crispa (Wulf.) belonging to the family of Sparassidaceae, has been widely used as an edible mushroom due to its unique flavor and functions to improve health. In this study, the compounds isolated from the extract of this mushroom were simultaneously quantified by the developed HPLC-DAD method and evaluated for the inhibitory activities on the production of the LPS-stimulated cytokines (IL-12p40, IL-6, and TNF-α) in bone marrow-derived dendritic cells (BMDCs). The contents of this compounds were 0.1928 ± 0.0118, 4.4137 ± 0.0240, 0.5237 ± 0.0005, 2.7303 ± 0.0206 mg/g for sparoside A (1), methyl 2,4-dihydroxy-3-methoxy-6-methylbenzoate (2), sparalide A (3), and 5′-deoxy-5′-methylthioadenosine (4), respectively, which demonstrated that they are the major constituents of this mushroom. Thus, our results were found that the sparoside A (1), 5-hydroxy-7-methoxyphthalide (6), 5-methoxy-7-hydroxyphthalide (7), nicotinamide (10), and adenosine (11) inhibit LPS-stimualted cytokine production, compound 6 is the most potent inhibitory activities on the production of IL-12p40, IL-6, and TNF-α with IC50 values of 0.19, 0.18, and 0.91 μM, respectively. [ABSTRACT FROM AUTHOR]

To determine the compounds responsible for its anti-influenza activities, we isolated the three flavonoids, 6-hydroxyluteolin 7-O-β-d-glucoside (1), nepitrin (2), homoplantaginin (3) from the MeOH extract of Salvia plebeia R.Br. and identified them by comparing the spectroscopic data with that reported in the literature. The contents of the three flavonoids in the whole extract were 108.74 ± 0.95, 46.26 ± 2.19, and 69.35 ± 1.22 mg/g for 6-hydroxyluteolin 7-O-β-d-glucoside, nepitrin, and homoplantaginin, respectively, which demonstrates that they are the major constituents of this plant. The three flavonoids were evaluated for their inhibitory activities against influenza virus H1N1 A/PR/9/34 neuraminidase and H1N1-induced cytopathic effect (CPE) on Madin-Darby canine kidney (MDCK) cells. Our results demonstrated the following arrangement for their anti-influenza activities: nepitrin (2) > 6-hydroxyluteolin 7-O-β-d-glucoside (1) > homoplantaginin (3). The potent inhibitory activities of these flavonoids against influenza suggested their potential to be developed as novel anti-influenza drugs in the future. [ABSTRACT FROM AUTHOR]

The fungal strain Alternaria alternata JS0515 was isolated from Vitex rotundifolia (beach vitex). Twelve secondary metabolites, including one new altenusin derivative (1), were isolated. The isolated metabolites included seven known altenusin derivatives (2–8), two isochromanones (9, 10), one perylenequinone (11), and one benzocycloalkanone (12). Their structures were determined via 1D and 2D nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry (MS), and computational electronic circular dichroism (ECD) analysis. Compounds 3 and 11 increased pyruvate dehydrogenase (PDH) activity in AD-293 human embryonic kidney cells and significantly inhibited PDH phosphorylation. The IC50 values of 3 and 11 were 32.58 and 27.82 μM, respectively. [ABSTRACT FROM AUTHOR]

Fluorescent carbon nanomaterials, especially zero-dimensional (0D) carbon nanodots (CDs), are widely used in broad biological and optoelectronic applications. CDs have unique characteristics such as strong fluorescence, biocompatibility, sun-light response, and capability of mass-production. Beyond the previous green CD obtained from harmful natural substances, we report a new type of fluid-based fluorescent CD paints (C-paints) derived from polyethylene glycol (PEG; via simple ultrasound irradiation at room temperatures) and produced in quantum yields of up to ~14%. Additionally, C-paints possess a strong, UV- and visible-light-responsive photoluminescent (PL) property. Most especially, C-paints, by incorporation into a photocatalytic system, show additional roles in the emission of fluorescent light for activation of TiO2 nanoparticles (NPs) and the resultant detoxification of most organic dyes, thus further enabling embarkation in advanced water purification. [ABSTRACT FROM AUTHOR]