A novel flavonoid and other constituents from Rubus rosifolius S.Vidal (Rosaceae).

Various reports revealed that chemical constituents from many species of Rubus exhibit diverse biological activities. In this study, a novel flavonoid with a 2-(phenanthren-9-yl)-4H-chromen-4-one structure (1), a 5-phenylthiophene-2-carbaldehyde derivative (5) first isolated from a natural source, together with five known compounds including three polyketides (2-4) and two sesquiterpenoids (6-7) were isolated from a traditional Chinese medicine Rubus rosifolius S.Vidal (Rosaceae). The structures of new compounds were elucidated by detailed spectroscopic analysis including NMR and X-ray single-crystal diffraction. The bioassays results indicated that, compound 1 displayed significant cytotoxicity against human colon cancer cell line HCT116 with IC50 value of 8.6 ± 1.9 µM, and compound 5 exhibited moderate cytotoxicity against human breast cancer cell line MDA-MB-435 with IC50 value of 24.1 ± 0.8 µM.

Metabolites with Anti-Inflammatory Activity from the Mangrove Endophytic Fungus Diaporthe sp. QYM12.

One new diterpenoid, diaporpenoid A (1), two new sesquiterpenoids, diaporpenoids B-C (2,3) and three new α-pyrone derivatives, diaporpyrones A-C (4-6) were isolated from an MeOH extract obtained from cultures of the mangrove endophytic fungus Diaporthe sp. QYM12. Their structures were elucidated by extensive analysis of spectroscopic data. The absolute configurations were determined by electronic circular dichroism (ECD) calculations and a comparison of the specific rotation. Compound 1 had an unusual 5/10/5-fused tricyclic ring system. Compounds 1 and 4 showed potent anti-inflammatory activities by inhibiting the production of nitric oxide (NO) in lipopolysaccharide (LPS)-induced RAW264.7 cells with IC50 values of 21.5 and 12.5 µM, respectively.

Chemical Composition and Anti-Alzheimer's Disease-Related Activities of a Functional Oil from the Edible Seaweed Hizikia fusiforme.

Cholinergic disorder, oxidative stress, and neuroinflammation play important roles in the pathology of Alzheimer's disease. To explore the healthy potential of the edible seaweed Hizikia fusiforme on this aspect, a functional oil (HFFO) was extracted from this alga and investigated on its constituents by gas chromatography-mass spectrometry (GC/MS) in this study. Its anti-Alzheimer's related bioactivities including acetylcholinesterase (AChE) inhibition, antioxidation, and anti-neuroinflammation were evaluated, traced, and simulated by in vitro and in silico methods. GC/MS analysis indicated that HFFO mainly contained arachidonic acid (ARA), 11,14,17-eicosatrienoic acid (ETrA), palmitic acid, phytol, etc. HFFO showed moderate AChE inhibition and antioxidant activity. Bioactivity tracing using commercial standards verified that AChE inhibition of HFFO mainly originated from ARA and ETrA, whereas antioxidant activity mainly from ARA. Lineweaver-Burk plots showed that both ARA and ETrA are noncompetitive AChE inhibitors. A molecular docking study demonstrated low CDOCKER interaction energy of -26.33 kcal/mol for ARA and -43.70 kcal/mol for ETrA when interacting with AChE and multiple interactions in the ARA (or ETrA)-AChE complex. In the anti-neuroinflammatory evaluation, HFFO showed no toxicity toward BV-2 cells at 20 µg/mL and effectively inhibited the production of nitroxide and reduced the level of reactive oxygen species in lipopolysaccharide-induced BV-2 cells. The results indicated that HFFO could be used in functional foods for its anti-Alzheimer's disease-related activities.

Bioactive polyketides from the mangrove endophytic fungi Phoma sp. SYSU-SK-7.

Five new polyketides, colletotric B (2), 3-hydroxy-5-methoxy-2,4,6-trimethylbenzoic acid (3), colletotric C (4), chaetochromone D (6) and 8-hydroxy-pregaliellalactone B (9), together with four known analogues (1, 5 and 7-8) were isolated from the mangrove endophytic fungus Phoma sp. SYSU-SK-7. Their structures were elucidated by analysis of extensive spectroscopic data and mass spectrometric data. Compounds 1-2 showed strong antimicrobial activity against the P. aeruginosa, MRSA and C. albicans with the MIC values in the range of 1.67-6.28 µg/ml. Furthermore, Compounds 1-5 also exhibited significant α-glucosidase inhibitory activity with the IC50 values in the range of 36.2-90.6 µM. Compound 7 was found to inhibited radical scavenging activity against DPPH with the EC50 value of 11.8 µM.