Quantitation of Toxic Steroidal Glycoalkaloids and Newly Identified Saponins in Post-Harvest Light-Stressed Potato ( 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.

Steroidal Saponins─New Sources to Develop Potato ( L.) Genotypes Resistant against Certain Strains.

Plant pathogens such as that caused the Irish Potato Famine continue to threaten local and global food security. Genetic and chemical plant protection measures are often overcome by adaptation of pathogen population structures. Therefore, there is a constant demand for new, consumer- and environment-friendly plant protection strategies.

Biosynthesis of α-solanine and α-chaconine in potato leaves (Solanum tuberosum L.) - A CO study.

α-Solanine and α-chaconine are the major glycoalkaloids (SGAs) in potatoes, but up to now the biosynthesis of these saponins is not fully understood. In plantaCO labeling experiments monitored by nuclear magnetic resonance spectroscopy (NMR) and high-resolution mass spectrometry (HRMS) unraveled the SGA biosynthetic pathways from CO photosynthates via early precursors to the SGAs. After a pulse of ~ 700 ppm CO for four hours, followed by a chase period for seven days, specific C-distributions were detected in SGAs from the leaves of the labeled plant.

Chemoprofiling as Breeding Tool for Pharmaceutical Use of .

Willow bark is traditionally used for pharmaceutical purposes. Evaluation is so far based on the salicylate content, however, health promoting effects of extracts might be attributed to the interaction of those salicylates with other compounds, which support and complement their action. So far, only , , and are included in pharmaceutical extracts.

Characterization of Bitter and Astringent Off-Taste Compounds in Potato Fibers.

Applying the sensomics approach, a combination of activity-guided fractionation and taste dilution analysis (TDA) followed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), ultrahigh-performance liquid chromatography time-of-flight mass spectrometry (UHPLC-TOF-MS), and one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy (1D/2D NMR) allowed the elucidation of key off-taste compounds in potato dietary fiber isolates. Previously already having been described as off-taste compounds in potato tubers, saponins α-chaconine and α-solanine were shown to be also major contributors to overall off-taste in potato fiber isolates. Moreover, fatty acids as well as fatty acid oxidation products, namely, -9,10,13-trihydroxy-octadec-11-enoic acid as well as newly identified compounds hexadecyl(/)-ferulate and octadecyl(/)-ferulate, were shown to be key inducers to off-taste in the isolates, exhibiting taste recognition thresholds between 18 and 981 μmol/L.

Comparative assessment of purified saponins as permeabilization agents during respirometry.

Saponins are a diverse group of secondary plant metabolites, some of which display hemolytic toxicity due to plasma membrane permeabilization. This feature is employed in biological applications for transferring hydrophilic molecules through cell membranes. Widely used commercial saponins include digitonin and saponins from soap tree bark, both of which constitute complex mixtures of little definition.

Hybridization of Lattice Resonances.

Plasmon hybridization, the electromagnetic analog of molecular orbital theory, provides a simple and intuitive method to describe the plasmonic response of complex nanostructures from the combination of the responses of their individual constituents. Here, we follow this approach to investigate the optical properties of periodic arrays of plasmonic nanoparticles with multiparticle unit cells. These systems support strong collective lattice resonances, arising from the coherent multiple scattering enabled by the lattice periodicity.