Asponchimides A-E: new enantiomeric N-acetyldopamine trimers from Aspongopus chinensis.

Five new racemic N-acetyldopamine (NADA) trimers, asponchimides A-E (1-5), were isolated from Aspongopus chinensis, a prominent traditional Chinese medicinal insect employed for alleviating pain, treating indigestion, and addressing kidney ailments. Compounds 1-5 were successfully resolved by chiral high-performance liquid chromatography (HPLC), yielding five pairs of enantiomers: (+)- and (-)-asponchimides A-E (1a/1b-5a/5b). Their structural identities were discerned by extensive spectroscopic analyses, including high-resolution mass spectrometry (HRMS), ultraviolet-visible (UV-Vis) spectroscopy, infrared (IR) spectroscopy, and nuclear magnetic resonance (NMR), and their absolute configurations were determined by electronic circular dichroism (ECD) calculations. Compounds 1-5 are pioneering instances of NADA trimers featuring a Δ7 double bond. When subjected to a series of bioassays, a majority of the compounds exhibited weak inhibitory activity against nitric oxide (NO) production in LPS-induced RAW 264.7 cells.

An inulin-type fructan isolated from Serratula chinensis alleviated the dextran sulfate sodium-induced colitis in mice through regulation of intestinal barrier and gut microbiota.

Herein, we aimed to explore the polysaccharide material basis of Serratula chinensis and establish its beneficial effects against colitis. A neutral polysaccharide (SCP) was extracted from S. chinensis in high yield using hot water. The molecular weights were calculated by HPSEC as Mw = 2928 Da, Mn = 2634 Da, and Mw/Mn = 1.11. FT-IR and 1D/2D-NMR spectroscopic analyses confirmed that SCP was an inulin-type fructan with α-D-Glcp-(1 â†’ [1)-ß-D-Fruf-(2]17) linkages. Treatment with SCP (200 or 400 mg/kg) alleviated dextran sulfate sodium (DSS)-induced mouse colitis symptoms, including the loss of body weight, increase of disease activity index score, and shortening of colon length. Histopathological and immunofluorescence assessments revealed that SCP could reduce pathological damage to the colon, restore the number of goblet cells, increase the content of glycoproteins in goblet cells and mucins in crypts, and enhance the expression of tight junction proteins ZO-1 and occludin. In addition, metagenomic sequencing revealed that SCP could improve the dysbiosis of gut microbiomes and act on multiple microbial functions. Moreover, SCP treatment increased the content of colonic acetic acid and butanoic acid. Collectively, these results indicated that SCP could alleviate the DSS-induced colitis in mice through regulation of intestinal barrier and gut microbiota.

Enantiomeric N-acetyldopamine trimers from Cicadae Periostracum and their absolute configurations.

Six previously undescribed N-acetyldopamine (NADA) trimmer racemates, percicamides A-F (1-6), were isolated from a 70% ethanol extract of Cicadae Periostracum. Subsequent chiral-phase separation afforded six pairs of enantiomers, (+)- and (-)-percicamides A-F (1a/1b-6a/6b). Their structures including absolute configurations were elucidated by combined extensive spectroscopic data and quantum chemical calculations. Compounds 1-6 represent the first examples of NADA trimmers with a cis-relationship of H-7'/H-8' or H-7''/H-8''. Bioassays verified that all isolated compounds showed weak inhibitory effects on nitric oxide production in RAW 264.7 cells.