Towards non-target proactive food safety: identification of active compounds in convenience tomato products by ten-dimensional hyphenation with integrated simulated gastrointestinal digestion.

Current strategies for non-target food screening focus mainly on known hazardous chemicals (adulterants, residues, contaminants, packaging migrants, etc.) instead of bioactive constituents in general and exclude the biological effect detection. To widen the perspective, a more proactive non-target effect-directed strategy is introduced to complement food safety in order to detect not only known but also unknown bioactive compounds. The developed 10-dimensional hyphenation included on-surface digestion (1D), planar chromatographic separation (2D), visualization using white light (3D), UV light (4D), fluorescence light (5D), effect-directed assay analysis (6D), heart-cut zone elution to an orthogonal reversed phase column chromatography including online desalting (7D) with subsequent diode array detection (8D), high-resolution mass spectrometry (9D), and fragmentation (10D). Metabolism, i.e., intestinal digestion of each sample, was simulated and integrated on the same adsorbent surface to study any changes in the compound profiles. As proof of principle, nine convenience tomato products and a freshly prepared tomato soup were screened via five different planar assays in a non-targeted mode. Non-digested and digested samples were compared side by side. In their effect-directed profiles, 14 bioactive compounds from classes of lipids, plant hormones, spices, and pesticides were identified. In particular, bioactive compounds coming from the lipid class were increased by gastrointestinal digestion, while spices and pesticides remained unaffected. With regard to food safety, the determination of the two dinitrophenol herbicides dinoterb and dinoseb in highly processed tomato products should be given special attention. The hyphenation covered a broad analyte spectrum and showed robust and reliable results.

Effect-Directed, Chemical and Taxonomic Profiling of Peppermint Proprietary Varieties and Corresponding Leaf Extracts.

During the development of novel, standardized peppermint extracts targeting functional applications, it is critical to adequately characterize raw material plant sources to assure quality and consistency of the end-product. This study aimed to characterize existing and proprietary, newly bred varieties of peppermint and their corresponding aqueous extract products. Taxonomy was confirmed through genetic authenticity assessment. Non-target effect-directed profiling was developed using high-performance thin-layer chromatography-multi-imaging-effect-directed assays (HPTLC-UV/Vis/FLD-EDA). Results demonstrated substantial differences in compounds associated with functional attributes, notably antioxidant potential, between the peppermint samples. Further chemical analysis by high-performance liquid chromatography-photodiode array/mass spectrometry detection (HPLC-PDA/MS) and headspace solid-phase microextraction-gas chromatography-flame ionization/MS detection (headspace SPME-GC-FID/MS) confirmed compositional differences. A broad variability in the contents of flavonoids and volatiles was observed. The peppermint samples were further screened for their antioxidant potential using the Caenorhabditis elegans model, and the results indicated concordance with observed content differences of the identified functional compounds. These results documented variability among raw materials of peppermint leaves, which can yield highly variable extract products that may result in differing effects on functional targets in vivo. Hence, product standardization via effect-directed profiles is proposed as an appropriate tool.

Comprehensive bioanalytical multi-imaging by planar chromatography in situ combined with biological and biochemical assays highlights bioactive fatty acids in abelmosk.

The identification of the bioactivity of individual compounds in natural products is helpful to understand their therapeutic applications. Thus, a bioanalytical multi-imaging screening was developed and applied to 54 bark, leaf and seed extracts of Sri Lankan Abelmoschus moschatus (abelmosk) to find out the most bioactive individual compounds. The focus was laid on a comprehensive bioactivity profiling of its extracts. High-performance thin-layer chromatography (HPTLC) was hyphenated with seven effect-directed assays (EDA), i. e. biological (Gram-negative Aliivibrio fischeri and Gram-positive Bacillus subtilis), biochemical (α-glucosidase, ß-glucosidase, acetylcholinesterase and tyrosinase) and chemical (2,2-diphenyl-1-picrylhydrazyl) assays. This multi-imaging was complemented by ultraviolet (UV), white light (Vis), fluorescence detection (FLD) and eight microchemical derivatizations. Heated electrospray ionization high-resolution mass spectrometry (HESI-HRMS) was used to characterize the most prominent multi-potent compound zone. It consisted of coeluting unsaturated fatty acids (linoleic acid and oleic acid), but also saturated fatty acids (palmitic acid and to a lower extent stearic acid, arachidic acid and behenic acid). For confirmation of the detected effects (antibacterial, free radical scavenger and inhibitor of α-glucosidase, ß-glucosidase, acetylcholinesterase and tyrosinase), oleic acid was exemplarily analyzed by co-development and overlapped application (with sample). The proven effects underlined the beneficial health effects derived from unsaturated fatty acids like oleic acid. Exemplarily, the α-glucosidase and tyrosinase inhibition responses of the multi-potent compound zone were quantified equivalently in reference to oleic acid. The comparable results obtained by two independent enzymatic responses successfully proved the use of biochemical quantification by planar enzyme assays, and thus the new method based on HPTLC-UV/Vis/FLD-EDA-HESI-HRMS.