Glucosinolates in Sisymbrium officinale (L.) Scop.: Comparative Analysis in Cultivated and Wild Plants and in Vitro Assays with T2Rs Bitter Taste Receptors

Biomarker Quantification, Spectroscopic, and Molecular Docking Studies of the Active Compounds Isolated from the Edible Plant Sisymbrium irio L

Phytochemical investigation of the ethanolic extract of the aerial parts of Sisymbrium irio L. led to the isolation of four unsaturated fatty acids (1–4), including a new one (4), and four indole alkaloids (5–8). The structures of the isolated compounds were characterized with the help of spectroscopic techniques such as 1D, 2D NMR, and mass spectroscopy, and by correlation with the known compounds. In terms of their notable structural diversity, a molecular docking approach with the AutoDock 4.2 program was used to analyze the interactions of the identified fatty acids with PPAR-γ and the indole alkaloids with 5-HT1A and 5-HT2A, subtypes of serotonin receptors, respectively. Compared to the antidiabetic drug rivoglitazone, compound 3 acted as a potential PPAR-γ agonist with a binding energy of −7.4 kcal mol−1. Moreover, compound 8 displayed the strongest affinity, with binding energies of −6.9 kcal/mol to 5HT1A and −8.1 kcal/mol to 5HT2A, using serotonin and the antipsychotic drug risperidone as positive controls, respectively. The results of docked conformations represent an interesting target for developing novel antidiabetic and antipsychotic drugs and warrant further evaluation of these ligands in vitro and in vivo. On the other hand, an HPTLC method was developed to quantify α-linolenic acid in the hexane fraction of the ethanol extract of S. irio. The regression equation/correlation coefficient (r2) for linolenic acid was Y = 6.49X + 2310.8/0.9971 in the linearity range of 100–1200 ng/band. The content of α-linolenic acid in S. irio aerial parts was found to be 28.67 μg/mg of dried extract.

Chemoinformatics View on Bitter Taste Receptor Agonists in Food

Food compounds with a bitter taste have a role in human health, both for their capability to influence food choice and preferences and for their possible systemic effect due to the modulation of extra-oral bitter taste receptors (TAS2Rs). Investigating the interaction of bitter food compounds with TAS2Rs is a key step to unravel their complex effects on health and to pave the way to rationally design new additives for food formulation or drugs. Here, we propose a collection of food bitter compounds, for which in vitro activity data against TAS2Rs are available. The patterns of TAS2R subtype-specific agonists were analyzed using scaffold decomposition and chemical space analysis, providing a detailed characterization of the associations between food bitter tastants and TAS2Rs.

Sisymbrium Officinale (the Singers' Plant) as an Ingredient: Analysis of Somatosensory Active Volatile Isothiocyanates in Model Food and Drinks

Sisymbrium officinale (L.) Scop. (hedge mustard) is a wild common plant of the Brassicaceae family. It is known as “the singers’ plant” for its traditional use in treating aphonia and vocal disability. The plant is rich in glucosinolates and isothiocyanates; the latter has been demonstrated to be a strong agonist in vitro of the Transient Receptor Potential Ankirine 1 (TRPA1) channel, which is involved in the somatosensory perception of pungency as well as in the nociception pathway of inflammatory pain. Volatile ITCs are released by the enzymatic or chemical hydrolysis of GLSs (glucosinolates) during sample crushing and/or by the mastication of fresh plant tissues when the plant is used as an ingredient. Some functional food and drink model preparations have been realised: honey enriched with seeds and flowers, infusions, cold drink (voice drink), artisanal beer, and a fermented tea (kombucha). Using SPME-GCMS chromatography, we analysed samples of the plant and of the food preparations adopting conditions that simulate the release of isothiocyanates (ITCs) during oral assumption. Two active compounds, iso-propylisothiocyanate and 2-butylisothiocyanate, have been assayed. The concentration of ITCs varies according to temperature, pH, grinding conditions, and different plant organs used. Kombucha-type fermentation seems to eliminate the ITCs, whereas they are retained in beer. The ITCs’ concentration is higher when entire seeds and flowers are used.