QuEChERS sample preparation was optimized and validated using solvent extraction with 10% (v/v) acetic acid-containing acetonitrile in the presence of four salts (anh. MgSO₄, NaCl, sodium citrate tribasic dihydrate and sodium citrate dibasic sesquihydrate) and dispersive solid-phase extraction with mixed sorbents (octadecylsilane, primary and secondary amine and silica sorbents) for an ultra high performance liquid chromatography–tandem mass spectrometric determination of nine mycotoxins in brown rice: aflatoxins (AFB1, AFB2, AFG1 and AFG2), fumonisins (FB1 and FB2), deoxynivalenol, ochratoxin A and zearalenone (ZON). Our developed method allows for the determination of trace levels of mycotoxins with method detection limits in the range of 1.4–25 µg/kg, below the maximum limits of EU regulations, and with an acceptable accuracy and precision, and recoveries in the range of 81–101% with relative standard deviations of 5–19% over a mycotoxin concentration range of 5.0–1,000 µg/kg. Six out of fourteen real samples of brown rice were found to be contaminated with at least one of these mycotoxins, ranging from 2.49–5.41 µg/kg of FB1, 4.33 ± 0.04 µg/kg of FB2 and 6.10–14.88 µg/kg of ZON.

Elephant dung coffee (Black Ivory Coffee) is a unique Thai coffee produced from Arabica coffee cherries consumed by Asian elephants and collected from their feces. In this work, elephant dung coffee and controls were analyzed using static headspace gas chromatography hyphenated with mass spectrometry (SHS GC-MS), and chemometric approaches were applied for multivariate analysis and the selection of marker compounds that are characteristic of the coffee. Seventy-eight volatile compounds belonging to 13 chemical classes were tentatively identified, including six alcohols, five aldehydes, one carboxylic acid, three esters, 17 furans, one furanone, 13 ketones, two oxazoles, four phenolic compounds, 14 pyrazines, one pyridine, eight pyrroles and three sulfur-containing compounds. Moreover, four potential discriminant markers of elephant dung coffee, including 3-methyl-1-butanol, 2-methyl-1-butanol, 2-furfurylfuran and 3-penten-2-one were established. The proposed method may be useful for elephant dung coffee authentication and quality control.

Three new halimane-type diterpenoids, crotohalimaneic acid (1), crotohalimoneic acid (2) and 12-benzoyloxycrotohalimaneic acid (3), were isolated from the stem bark of Croton oblongifolius Roxb. Their structures were established on the basis of spectroscopic and X-ray analysis. Compounds 1 and 2 showed non-specific strong cytotoxicity against a panel of human tumor cell lines; whereas 3 was inactive.