Quinoa plant is a valuable food crop because of its high nutritional and functional values. Total saponin content, sapogenins, polyphenol, and flavonoid contents and antioxidant activities were analyzed in various parts of quinoa plants, including sprout, seeds, bran, pericarp, leave, stem, and root. Quinoa seeds (QS) had significantly higher sapogenin content than quinoa stem (QT), quinoa leaves (QL), and quinoa roots (QR). Quinoa saponin was mainly composed of phytolaccagenic acid. Quinoa root (QR) had the highest amount of total saponin (13.39 g 100 g⁻¹), followed by quinoa bran. The highest total phenolic content (30.96 mg GAE 100 g⁻¹) and total flavonoid content (61.68 mg RE 100 g⁻¹) were observed in quinoa root extract and 1‐month‐old sprout extract, respectively. Quinoa sprouts showed better antioxidant activity than fully grown parts of the quinoa plant. Overall, root and sprout had a higher antioxidant capacity compared to other parts of the quinoa plant, suggesting the potential use of quinoa root and sprout as a nutraceutical ingredient in the health food industry.

Heterocyclic amines (HCAs) and acrylamide are unintended hazardous substances generated by heating or processing of foods and are known as carcinogenic and mutagenic agents by the animal experiments. A simple method was established for a rapid and accurate determination of 12 types of HCAs (IQ, MeIQ, Glu-P-1, Glu-P-2, MeIQx, Trp-P-1, Trp-P-2, PhIP, AαC, MeAαC, Harman and Norharman) and acrylamide in three food matrices (non-fat liquid, non-fat solid and fat solid) by isotope dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS). In every sample, a mixture of internal standards including IQ-d3, MeIQx-d3, PhIP-d3, Trp-P-2-(13)C2-(15)N and MeAαC-d3 was spiked for quantification of HCAs and (13)C3-acrylamide was also spiked for the analysis of acrylamide. HCAs and acrylamide in sample were extracted with acetonitrile and water, respectively, and then two solid-phase extraction cartridges, ChemElut: HLB for HCAs and Accucat: HLB for acrylamide, were used for efficiently removing interferences such as pigment, lipid, polar, nonpolar and ionic compounds. Established method was validated in terms of recovery, accuracy, precision, limit of detection, limit of quantitation, and linearity. This method showed good precision (RSD < 20%), accuracy (71.8~119.1%) and recovery (66.0~118.9%). The detection limits were < 3.1 ng/g for all analytes. The correlation coefficients for all the HCAs and acrylamide were > 0.995, showing excellent linearity. These methods for the detection of HCAs and acrylamide by LC-MS/MS were applied to real samples and were successfully used for quantitative monitoring in the total diet study and this can be applied to risk assessment in various food matrices.

A method for simultaneous determination of 12 priority phthalates, adipate and polycyclic aromatic hydrocarbons (PAHs) in edible oils by isotope dilution-gas chromatography–mass spectrometry (ID-GC–MS) was developed for fast, accurate and trace analysis. The extraction and clean-up procedures were optimised, and using stable isotope-labelled internal standards for each analyte, relative standard deviations (RSDs) of 0.92–10.6% and spiked sample recoveries of 80.6–97.8% were obtained. Limits of detection for PAHs were in the range of 0.15–0.77 µg/kg and those for phthalates were in the range of 4.6–10.0 µg/kg. The calibration curves exhibited good linearities with regression coefficients of R² ≥ 0.99. Twelve edible oils were examined to evaluate the efficiency of this method. Among the 12 analytes, dibutyl phthalates (DBP), diethylhexyl phthalates (DEHP), diethylhexyl adipate (DEHA), benzo[a]anthracene (B[a]A), chrysene (Chry) and benzo[b]fluoranthene (B[b]F) were detected in the range of 1.17–806 µg/kg.

HER2-positive (HER2+) breast cancer is defined by HER2 oncogene amplification on chromosome 17q12 and accounts for 15–20% population of breast-cancer patients. Therapeutic anti-HER2 antibody such as trastuzumab is used as the first-line therapy for HER2-positive breast cancers. However, more than 50% of the patients respond poorly to trastuzumab, illustrating that novel therapy is warranted to overcome the resistance. We previously reported that in the majority of HER2+ breast-cancer patients, CDK12 is co-amplified on 17q12 and involved in developing tumors and trastuzumab resistance, proposing CDK12 as a potential drug target for HER2+ breast cancers. Here, we designed and synthesized novel 2,6,9-trisubstituted purines as potent CDK12 inhibitors showing strong, equipotent antiproliferative activity against trastuzumab-sensitive HER2+ SK-Br3 cells and trastuzumab-resistant HER2+ HCC1954 cells (GI₅₀ values < 50 nM) both of which express a high level of CDK12. Two potent analogue 30d and 30e at 40, 200 nM greatly downregulated the levels of cyclinK and Pol II p-CTD (Ser2), as well as the expression of CDK12 downstream genes (IRS1 and WNT1) in a dose-dependent manner. We also observed structure-property relationship for a subset of potent analogues, and found that 30e is highly stable in liver microsomes with lack of CYP inhibition. In addition, 30d exhibited a synergy with trastuzumab in the both cells, suggesting that our inhibitors could be applied to alleviate trastuzumab-resistance of HER2+ breast cancers and escalate the efficacy of trastuzumab as well. Our study may provide insight into developing a novel therapy for HER2+ breast cancers.

Heterocyclic amines (HCAs) are potent mutagens generated by the high temperatures of the cooking process. The purpose of this study was to develop and validate analytical methods for HCAs determination using high-performance liquid chromatography-tandem mass spectrometry in seven food matrices: corn oil, milk, 20% ethanol, pork, flat fish, sea mustard (Undaria pinnatifida), and radish. Six isotopically labelled internal standards were used for quantitation, and Chem Elut and Oasis hydrphilic-liphophilic balance cartridges were applied for sample preparation to remove interferences. Calibration curves showed good linearity (R² > 0.99) in all matrices. The ranges of the method detection limit and method quantitation limit were 0.009–2.35 ng g⁻¹ and 0.025–7.13 ng g⁻¹, respectively. The recoveries ranged from 67.5% to 119.6%. The coefficients of variation ranged from 0.3% to 15.1% for intra-day and ranged from 0.8% to 19.1% for inter-day. The methods were applied to 24 total diet study samples for HCAs quantitation. These results indicate that the established methods are reliable for determining HCAs in various foods.

Heterocyclic amines (HCAs) are contaminants in proteinaceous foods produced by cooking at high temperatures. This study was the first assessment of exposure to HCAs using the Korean total diet study. Twelve HCAs were analysed in 1,232 pooled samples using six isotope-labelled internal standards and HPLC-MS/MS. The daily intake of HCAs in the Korean population was estimated based on the concentration of HCAs in the total diet study samples and individual food consumption data from the Korean National Health and Nutrition Examination Survey. Among HCAs, the intake of β-carbolines, such as harman and norharman, was the highest, followed by the intake of PhIP. The primary sources of HCA intake were meat, fish, shellfish, and beverages, including alcohol. The margin of exposure to PhIP was 2,349,000 at the average level and 373,000 at the 95^th percentile in the Korean population. The estimated daily intake of all HCAs in the Korean population was considered safe.