New 4',5'-methylenedioxyflavone derivatives from the whole plant of Sarcandra glabraTwo new natural products named 5,7-dihydroxy-3,3',6,8-tetramethoxy-4',5'methylenedioxyflavone (1), and 3,3',5,7-tetramethoxy-4',5'methylenedioxyflavone (2), along with thirteen known compounds, β-sitosterol (3), desmethoxyyangonin (4), hexadecane (5), 3,9-bis(2,4-di-tert-butylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane 3,9-dioxide ( 6), 2'6'dihydroxy-4'-methoxydihydrochalcone (7), cardamonin (8), 3,3',5,6,7,8hexamethoxy-4',5'-methylenedioxyflavone (9), isofraxidin (10), aniba dimer A (11), 3,3',4',5,5',8-hexamethoxy-6,7-methylenedioxyflavone (12), quercetin (13), quercitrin ( 14) and isoquercitrin (15) were isolated from Sarcandra glabra (Thunb.) Nakai by various chromatographic methods. Compounds 1, 2, 4, 6, 11, and 12 were isolated from S. glabra for the first time. Their chemical structures were identified through the analysis of NMR and HR-MS spectra. The antiinflammatory and cytotoxic activities of compounds 1-15 were evaluated in cell assays. The results indicated that compounds 1, 7, 8, 10, 14, and 15 significantly inhibited the NO production in LPS-induced RAW 264.7 murine macrophage cells. Moreover, compounds 1, 3, 4, 7, 8, 9, 10 and 12 exhibited a cytotoxic effect on the human HepG2 cell line.

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Oxytetracycline (OTC) is a widely used antibiotic in veterinary practices because of its broad-spectrum antibacterial activity and low cost. However, drug abuse has triggered adverse effects on human health, which brings a growing demand for on-site diagnosis of OTC residues in animal-derived foods. In this study, we demonstrate the combined use of interdigital electrode microarray and electrochemiluminescence (ECL) imaging for parallel multiplex measurement of OTC. Well-ordered and vertically aligned mesoporous silica nanochannels modified on microarray substrate could exert a strong electrostatic attraction to the ECL luminophores and accelerate their mass transport to generate enhanced ECL signal. The performance of the integrated ECL microarray sensor was fully validated with respect to linearity (0.5 to 50 μM), sensitivity (limit of detection 0.26 μM), accuracy (recovery rate between 96.78% and 106.1%), low operating sample volume (480 nL), short assay time (1.5 min), and antifouling ability toward complex media. The multiplex microarray platform can serve as a simple, fast, and low-cost tool for the detection of a wide spectrum of antibiotics in the field of food safety.