Quantitation of Toxic Steroidal Glycoalkaloids and Newly Identified Saponins in Post-Harvest Light-Stressed Potato (Solanum tuberosum L.) Varieties.

Although domesticated potatoes contain a large variety of steroidal glycoalkaloids (SGAs) and saponins, in the past, many research projects mainly focused on the two major SGAs, α-solanine and α-chaconine. This study investigates the quantitative changes, induced by post-harvest LED light exposure, of six SGAs and four saponins in 12 potato cultivars at three different time points (1, 7, and 16 days), by using ultra-performance liquid chromatography tandem mass spectrometry. Altogether, SGA contents of 3.0-17.1 mg/100 g fresh weight (FW) could be observed in the analyzed tubers with potato varieties highly exceeding the newly discussed safety limit of 10 mg/100 g. The overall contents of 0.1-5.4 mg/100 g FW of the so far barely studied saponins, like protoneodioscin or barogenin-solatrioside, highly differed between the assayed potato cultivars. Furthermore, cultivar-specific regulations of SGAs and saponins could be observed due to light exposure.

A Phase I Trial to Determine the Pharmacokinetics, Psychotropic Effects, and Safety Profile of a Novel Nanoparticle-Based Cannabinoid Spray for Oromucosal Delivery.

INTRODUCTION: A phase I, open-label clinical trial in healthy male subjects was conducted to assess the pharmacokinetic and safety profile of an oromucosal cannabinoid spray (AP701) containing a lipid-based nanoparticular drug formulation standardized to ∆-9-tetrahydrocannabinol (THC). METHODS: Twelve healthy male subjects received a single dose of AP701 (12 sprays) containing 3.96 mg THC. Plasma samples were drawn 10 min-30 h post dose for analysis of THC and the active metabolite 11-hydroxy-∆-9-THC (11-OH-THC). RESULTS: The single dose of the applied oromucosal cannabinoid spray AP701 (12 sprays, 3.96 mg THC) resulted in a mean maximum plasma concentration (Cmax) of 2.23 ng/mL (90% CI 1.22-3.24) and a mean overall exposure (area under the concentration-time curve from time 0 to last measurable concentration [AUC0-t]) of 7.74 h × ng/mL (90% CI 5.03-10.45) for THC. For the active metabolite 11-OH-THC, a Cmax of 2.09 mg/mL (90% CI 1.50-2.68) and AUC0-t of 10.4 h × ng/mL (90% CI 7.03-13.77) was found. The oromucosal cannabinoid spray AP701 caused only minor psychotropic effects despite the relatively high dosage applied by healthy subjects. No serious adverse effects occurred. Overall, the oromucosal cannabinoid spray AP701 was well tolerated. CONCLUSION: Compared to currently available drugs on the market, higher AUC values could be detected for the oromucosal cannabinoid spray AP701 despite administration of a lower dose. These comparatively higher blood levels caused only minor psychotropic adverse effects. The oromucosal cannabinoid spray AP701 was well tolerated at a single dose of 3.96 mg THC. The oromucosal administration may provide an easily applicable and titratable drug formulation with a high safety and tolerability profile.

Quantitative Determination of Thiamine-Derived Taste Enhancers in Aqueous Model Systems, Natural Deep Eutectic Solvents, and Thermally Processed Foods.

To obtain high-kokumi-active building blocks, which can be used to produce savory process flavors, it is essential to obtain a better understanding on the formation rate of kokumi-active compounds, such as 3-(((4-amino-2-methylpyrimidin-5-yl)methyl)thio)-5-hydroxypentan-2-one or 2-methyl-5-(((2-methylfuran-3-yl)thio)methyl)pyrimidin-4-amine. The present work showed quantitative studies in several model reaction systems on the recently discovered kokumi-active thiamine derivates. It was possible to show that the thiamine conversion in aqueous model reactions could be directed toward the taste-modulating compounds by adjusting the pH value (6.5), the heating time (120 min), and the heating temperature (120 °C). With the development of a new natural deep eutectic solvents (NADES) system consisting of thiamine, cysteine, ribose, and sodium hydroxide, it was possible to obtain high yields of the targeted taste-modulating analytes, such as 3-(((4-amino-2-methylpyrimidin-5-yl)methyl)thio)-5-hydroxypentan-2-one and 2-methyl-5-(((2-methylfuran-3-yl)thio)methyl)pyrimidin-4-amine. Furthermore, the current study showed that kokumi-active thiamine derivates, such as S-((4-amino-2-methylpyrimidin-5-yl)methyl)-l-cysteine, 3-(((4-amino-2-methylpyrimidin-5-yl)methyl)thio)-5-hydroxypentan-2-one, 2-methyl-5-(((2-methylfuran-3-yl)thio)methyl)pyrimidin-4-amine, and 5-(((furan-2-ylmethyl)thio)methyl)-2-methylpyrimidin-4-amine, can be classified as natural "food-borne" taste enhancers and occur in thiamine-rich, thermally treated foodstuff.

Novel Taste-Enhancing 4-Amino-2-methyl-5-heteroalkypyrimidines Formed from Thiamine by Maillard-Type Reactions.

Increasing the thiamine concentration in a respective process flavor yields a product with a significant higher kokumi activity. S-plot analysis of the mass spectrometric data revealed beside thiamine itself, 4-methyl-5-thiazoleethanol, (S)-((4-amino-2-methylpyrimidin-5-yl)methyl)-l-cysteine, N-((4-amino-2-methylpyrimidin-5-yl)methyl)formamide, 3-(((4-amino-2-methylpyrimidin-5-yl)methyl)thio)-5-hydroxypentan-2-one, and 2-methyl-5-(((2-methylfuran-3-yl)thio)methyl)pyrimidin-4-amine as marker molecules for a process flavor with higher thiamine concentration. Sensory-based targeted isolation revealed that (S)-((4-amino-2-methylpyrimidin-5-yl)methyl)-l-cysteine, 3-(((4-amino-2-methylpyrimidin-5-yl)methyl)thio)-5-hydroxypentan-2-one, and 2-methyl-5-(((2-methylfuran-3-yl)thio)methyl)pyrimidin-4-amine showed an influence on the kokumi taste activity with taste threshold concentrations between 35 and 120 µmol/L. An adapted mass spectrometric-based carbon module labeling experiment as well as quantitative studies clearly demonstrated thiamine as the only precursor and an intermolecular formation pathway for the compounds (S)-(((4-amino-2-methylpyrimidin-5-yl)methyl)thio)-5-hydroxypentan-2-one and 2-methyl-5-(((2-methylfuran-3-yl)thio)methyl)pyrimidin-4-amine. On the basis of the knowledge that several thiamine derivatives showed taste-modulating activity, selected thiamine-based binary model reactions and synthesis were carried out. This resulted in the isolation of further thiamine-derived taste modulators like (S)-((4-amino-2-methylpyrimidin-5-yl)methyl)-l-cysteinylglycine, (S)-3-((((4-amino-2-methylpyrimidin-5-yl)methyl)thio)methyl)piperazine-2,5-dione, 3-(((4-amino-2-methylpyrimidin-5-yl)methyl)thio)pentan-2-one, 5-(((furan-2-ylmethyl)thio)methyl)-2-methylpyrimidin-4-amine, and (4-amino-2-methylpyrimidin-5-yl)methanethiol, 2-methyl-5-((methylthio)methyl)pyrimidin-4-amine with taste thresholds ranging from 35 to 880 µmol/L.

Discovery of a Thiamine-Derived Taste Enhancer in Process Flavors.

Targeted quantitation of 48 basic taste-active compounds in commercial meatlike process flavors, calculation of dose-overthreshold factors, and basic taste re-engineering, followed by activity-guided fractionation, revealed, next to l-glutamate and 5'-ribonucleotides, a series of N-acetylated amino acids and S-((4-amino-2-methylpyrimidin-5-yl)methyl)-l-cysteine as taste-modulating compounds. The N-acetylated amino acids imparted kokumi enhancement with rather high taste thresholds ranging up to 1800 µmol/L ( N-acetylmethionine) in model broth. In comparison, S-((4-amino-2-methylpyrimidin-5-yl)methyl)-l-cysteine, found to be formed by a Maillard-type reaction of thiamine and cysteine, is reported for the first time to exhibit strong kokumi enhancement above a low threshold concentration of 120 µmol/L (model broth). These results will open new avenues toward a knowledge-based optimization of thiamine-containing process flavors.