Bioactive Substances of Potato Juice Reveal Synergy in Cytotoxic Activity against Cancer Cells of Digestive System Studied In Vitro.

More and more literature data indicate the health-promoting effect of potato juice (PJ). However, to date, it has not been precisely explained which of the many compounds present in PJ exhibit biological activity. The work aimed to establish the antiproliferative effect of gastrointestinal digested PJ and the products of its processing. Fresh PJs derived from three edible potato varieties, industrial side stream resulting from starch production, partially deproteinized PJ derived from feed protein production line, and three different potato protein preparations subjected to digestion in the artificial gastrointestinal tract were used in this study. The cytotoxic potential of glycoalkaloids (GAs), phenolic acids, digested PJ, and products of PJ processing was determined in human normal and cancer cells derived from the digestive system. The results showed that GAs exhibit concentration-dependent cytotoxicity against all analyzed cell lines. In contrast, phenolic acids (caffeic, ferulic, and chlorogenic acid) do not show cytotoxicity in the applied cell lines. A correlation between cytotoxic potency and GAs content was found in all PJ products studied. The most potent effects were observed under treatment with deproteinized PJ, a product of industrial processing of PJ, distinguished by the highest effective activity among the fresh juice products studied. Moreover, this preparation revealed a favorable cytotoxicity ratio towards cancer cells compared to normal cells. Statistical analysis of the obtained results showed the synergistic effect of other bioactive substances contained in PJ and its products, which may be crucial in further research on the possibility of using PJ as a source of compounds of therapeutic importance.

Comparison of Three Extraction Techniques for the Determination of Volatile Flavor Components in Broccoli.

To analyze aroma active components in a food product, the crucial step is to select a suitable extraction technique. It should provide isolation of all components responsible for aroma creation, without the formation of any artifacts during the procedure. Preferably, the extraction method should yield analyzed compounds in detectable levels. The presented study aimed to compare three popular extraction techniques used in flavor studies: solid-phase microextraction (SPME), solvent-assisted flavor evaporation (SAFE), and simultaneous distillation extraction (SDE) in order to isolate aroma components from broccoli (Brassica oleracea L. var. italica). Obtained extracts were analyzed by gas chromatography-olfactmetry (GC-O) to determine compounds with aroma activity as well as gas chromatography-mass spectrometry (GC-MS) and comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC×GC-ToFMS) to identify them. Thirty-four aroma active compounds were detected in broccoli by the applied techniques. SPME and SAFE together gave the full profile of aroma active components on chromatograms from GC-O, without artifacts that occurred in the SDE extract. SPME was particularly useful in the identification of early eluting compounds, while SAFE enabled isolating compounds with relatively low partition coefficients. Despite all the disadvantages of the SDE method, it leads to the identification of pyrazines, which were important contributors to the overall aroma.