Monitoring of airborne particulate matter at mountainous urban sites.

Concentrations of various size fractions (TSP, PM10, PM2.5, and PM1.0) of particulate matter (PM) were measured at two mountainous sites, Buk Han (BH) and Gwan AK (GA), along with one ground reference site at Gwang Jin (GJ), located in Seoul, South Korea for the 4 years from 2010 to 2013.

Triterpenoic acids of Prunella vulgaris var. lilacina and their cytotoxic activities in vitro.

The column chromatographic separation of the MeOH extract from the aerial parts of Prunella vulgaris var. lilacina Nakai led to the isolation of fifteen triterpenoic acids (2-6, 9-13, 16-20), four flavonoids (14, 21-23), four phenolics (7, 8, 15, 24), and a diterpene (1). Their structures were determined by spectroscopic methods to be trans-phytol (1), oleanic acid (2) ursolic acid (3), 2alpha,3alpha,19alpha-trihydroxyurs-12en-28oic acid (4), 2alpha,3alpha-dihydroxyurs-12en-28oic acid (5), maslinic acid (6), caffeic acid (7), phydroxy cinnamic acid (8), 2alpha,3alpha,19alpha,23-tetrahydroxyurs-12en-28oic acid (9), 2alpha,3alpha,23-trihydroxyurs-12en-28oic acid (10), 2alpha,3beta-dihydroxyurs-12en-28oic acid (11), 2alpha,3beta,24-trihydroxyolea-12en-28oic acid (12), (12R, 13S)-2alpha,3alpha,24,trihydroxy-12,13-cyclo-taraxer-14-en-28oic acid (13), quercertin 3-O-beta-D-glucopyranoside (14), rosmarinic acid (15), 2alpha,3alpha,24-trihydroxyurs-12,20(30)-dien-28oic acid (16), 2alpha,3alpha,24-trihydroxyolea-12en-28oic acid (17), 2alpha,3beta,19alpha,24-tetrahydroxyurs-12en-28oic acid 28-O-Dglucopyranoside (18), 2alpha,3alpha,19alpha,24-tetrahydroxyurs-12en-28oic acid 28-O-D-glucopyranoside (19), prunvuloside A (20), kaempferol 3-O-alpha-L-rhamnopyranosyl(1-->6)-beta-D-glucopranoside (21), kaempferol 3-O-beta-D-glucopyranoside (22), quercertin 3-O-alpha-L-rhamnopyranosyl(1-->6)-beta-D-glucopyranoside (23), and 2-hydroxy-3-(3',4'-dihydroxyphenly)propanoic acid (24).

Combined isobutoxycarbonylation and tert-butyldimethylsilylation for the GC/MS-SIM detection of alkylphenols, chlorophenols and bisphenol A in mackerel samples.

The alkylphenols, chlorophenols, and bisphenol A were determined by gas chromatography/mass spectrometry-selected ion monitoring (GC/MS-SIM) followed by two work-up methods for comparison: isobutoxycarbonyl (isoBOC) derivatization and tert-butyldimethylsilyl (TBDMS) derivatization. Eleven endocrine disrupting chemicals (EDCs) of phenols in biological samples were extracted with acetonitrile and then the acetonitrile layer underwent freezing filtration 60 degrees C for 2 hours. Solid-phase extraction (SPE) was used with XAD-4 and subsequent conversion to isoBOC or TBDMS derivatives for sensitivity analysis with the GC/MS-SIM mode.

Determination of non-steroidal estrogens in breast milk, plasma, urine and hair by gas chromatography/mass spectrometry.

It is suspected that all the natural estrogens occurring in the human body, as well as dietary and synthetic estrogens, diversely affect the endocrine system depending on their exposure patterns. More rapid, reliable and accurate measurements of these compounds in various biological matrices are thus becoming an important task. After solid-phase extraction using an Oasis HLB extraction cartridge, the estrogen concentrates were derivatized with a mixture of N-methyl-N-trifluorotrimethylsilylacetamide/ammonium iodide/dithioerythritol (1000:4:5, v/w/w) for analysis by gas chromatography/mass spectrometry in the selected ion-monitoring (SIM) mode.