In our previous study, all Arthrinium isolates from Sargassum sp. showed high bioactivities, but studies on marine Arthrinium spp. are insufficient. In this study, a phylogenetic analysis of 28 Arthrinium isolates from seaweeds and egg masses of Arctoscopus japonicus was conducted using internal transcribed spacers, nuclear large subunit rDNA, β-tubulin, and translation elongation factor region sequences, and their bioactivities were investigated. They were analyzed as 15 species, and 11 of them were found to be new species. Most of the extracts exhibited radical-scavenging activity, and some showed antifungal activities, tyrosinase inhibition, and quorum sensing inhibition. It was implied that marine algicolous Arthrinium spp. support the regulation of reactive oxygen species in symbiotic algae and protect against pathogens and bacterial biofilm formation. The antioxidant from Arthrinium sp. 10 KUC21332 was separated by bioassay-guided isolation and identified to be gentisyl alcohol, and the antioxidant of Arthrinium saccharicola KUC21221 was identical. These results demonstrate that many unexploited Arthrinium species still exist in marine environments and that they are a great source of bioactive compounds.

A bioassay-guided isolation using a green fluorescence protein (GFP)-tagged pepper mottle virus (PepMoV-GFP) based leaf-disk method to obtain new antiviral agents led to the isolation of trichodermin, 1, and a new compound trichoderminol, 2, from EtOAc extract of Trichoderma albolutescens culture medium. The structures of compounds 1 and 2 were determined by MS and NMR experiments, and the absolute configurations of the compounds were established by experimental and calculated vibrational circular dichroism spectra. Compounds 1 and 2 were evaluated for their anti-PepMoV potential in systemic host plants, such as tobacco and pepper, by PepMoV-GFP based systemic host method. All compounds exhibited inactivation effects against PepMoV. Furthermore, compound 1 showed protective effects against PepMoV.

Two new aryltetralin lactone lignans, petasitesins A and B were isolated from the hot water extract of the leaves of butterbur (Petasites japonicus) along with six known compounds. The chemical structures of lignans 1 and 2 were elucidated on the basis of 1D and 2D nuclear magnetic resonance (NMR) spectroscopic data, electronic circular dichroism (ECD) and vibrational circular dichroism (VCD) spectra. Petasitesin A and cimicifugic acid D showed significant inhibitory effects on the production of both prostaglandin E2 (PGE2) and NO in RAW264.7 macrophages. The expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were inhibited by compound 1 in RAW264.7 cells. Furthermore, compounds 1 and 3 exhibited strong affinities with both iNOS and COX-2 enzymes in molecular docking studies.

Parkinson's disease (PD) is characterized by dopaminergic neuronal loss in the substantia nigra pars compacta (SNPC) and the striatum. Nuclear receptor-related 1 protein (Nurr1) is a nuclear hormone receptor implicated in limiting mitochondrial dysfunction, apoptosis, and inflammation in the central nervous system and protecting dopaminergic neurons and a promising therapeutic target for PD. Cicadidae Periostracum (CP), the cast-off skin of Cryptotympana pustulata Fabricius, has been used in traditional medicine for its many clinical pharmacological effects, including the treatment of psychological symptoms in PD. However, scientific evidence for the use of CP in neurodegenerative diseases, including PD, is lacking. Here, we investigated the protective effects of CP on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine- (MPTP-) induced PD in mice and explored the underlying mechanisms of action, focusing on Nurr1. CP increased the expression levels of Nurr1, tyrosine hydroxylase, DOPA decarboxylase, dopamine transporter, and vesicular monoamine transporter 2 via extracellular signal-regulated kinase phosphorylation in differentiated PC12 cells and the mouse SNPC. In MPTP-induced PD, CP promoted recovery from movement impairments. CP prevented dopamine depletion and protected against dopaminergic neuronal degradation via mitochondria-mediated apoptotic proteins such as B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X, cytochrome c, and cleaved caspase-9 and caspase-3 by inhibiting MPTP-induced neuroinflammatory cytokines, inducible nitric oxide synthase, cyclooxygenase 2, and glial/microglial activation. Moreover, CP inhibited lipopolysaccharide-induced neuroinflammatory cytokines and response levels and glial/microglial activation in BV2 microglia and the mouse brain. Our findings suggest that CP might contribute to neuroprotective signaling by regulating neurotrophic factors primarily via Nurr1 signaling, neuroinflammation, and mitochondria-mediated apoptosis.

A new flavone glucoside, acacetin-7-O-(3″-O-acetyl-6″-O-malonyl)-β-d-glucopyranoside (1), two new phenolic glucosides, (3R,7R)-tuberonic acid-12-O-[6′-O-(E)-feruloyl]-β-d-glucopyranoside (14) and salicylic acid-2-O-[6′-O-(E)-feruloyl]-β-d-glucopyranoside (15), and two new phenylpropanoid glucosides, chavicol-1-O-(6′-O-methylmalonyl)-β-d-glucopyranoside (17) and chavicol-1-O-(6′-O-acetyl)-β-d-glucopyranoside­(18), as well as 26 known compounds, 2–13, 16, and 19–31, were isolated from the aerial parts of Agastache rugose. The structures of the new compounds were established by spectroscopic/spectrometric methods such as HRESIMS, NMR, and ECD. The anti-inflammatory effect of the isolated compounds was evaluated by measuring their inhibitory activities on prostaglandin E2 (PGE2) in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. New compounds 1, 15, 17, and 18 inhibited LPS-induced PGE2 production with IC50 values of 16.8 ± 0.8, 33.9 ± 4.8, 14.3 ± 2.1, and 48.8 ± 4.4 μM, respectively. Compounds 5, 7, 9−11, 13, 19, 20, 22, and 27–30 showed potent inhibitory activities with IC50 values of 1.7–8.4 μM.