vitisin-a and malvidin-3-glucoside

In this study, the gastric transport efficiency of malvidin-3-glucoside and several derivatives was assayed on the MKN-28 cell model. The transport efficiency was found to increase for all compounds with the incubation time. Pyranoanthocyanins may slightly impair transport efficiency levels in comparison with native anthocyanins. Among the pyranoanthocyanin derivatives the presence of the carbonyl group and the absence of charge were important for the transport efficiency percentage of oxovitisin and apparently compensated the negative effect associated with the additional ring. Moreover, the antiproliferative properties of these compounds in the MCF-7 cancer cell line were assayed, oxovitisin being the most effective compound in inhibiting the proliferation of MCF-7 cells. Also, a kinetic incorporation of oxovitisin was assayed revealing that this pyranoanthocyanin is quickly incorporated into cells. This study confirms the importance of the natural micro-oxidative processes that occur during the ageing of anthocyanin-containing food and their impact on their bioavailability and bioactivity properties.

Topics: Anthocyanins; Antineoplastic Agents; Antioxidants; Benzofurans; Biological Availability; Cell Line, Tumor; Cell Proliferation; Gastric Mucosa; Glucosides; Humans; MCF-7 Cells; Mitochondria; Phenols; Pyrones; Rhodamines; Vitis

The formation of vitisin A, an anthocyanin formed naturally in small quantities in maturing port wines, was studied in model wine solutions at several storage temperatures (10, 15, 20, and 32 degrees C). Vitisin A was formed through the interaction between malvidin 3-glucoside and pyruvic acid, Acylated forms of vitisin A, having the 6-position of the sugar acylated with acetic acid (3-acetylvitisin A) and p-coumaric acid (3-p-coumarylvitisin A), were also formed through the interaction between pyruvic acid and malvidin 3-acetylglucoside and malvidin 3-p-coumarylglucoside, respectively. A maximum degradation of the anthocyanins was obtained at higher temperatures, and it followed a first-order kinetics both with and without pyruvic acid in the solution. Whereas at low temperatures (10 and 15 degrees C) the presence of pyruvic acid accelerated the kinetic reaction, at higher temperatures (20 and 32 degrees C) it decreased it. The activation energy values for the degradation of the three anthocyanins in model solutions without and with pyruvic acid were not significantly different from each other. At low temperatures the highest concentrations of vitisin A compounds were obtained. All solutions showed a decrease in L value, indicating that all solutions became darker. This change increased with increasing temperature. All model solutions increased in the hue angle, indicating that the solutions changed from a bluish-red to an orange-red or even brownish-red color. Samples without pyruvic acid remained lighter and became browner than those with pyruvic acid. A good correlation between the amount of vitisin A in the solution and hue angle was found, indicating that vitisin A may contribute the orange-red of solutions, compared to the browner control.

Topics: Acetylation; Anthocyanins; Benzofurans; Coumaric Acids; Food Handling; Glucosides; Kinetics; Phenols; Pyruvic Acid; Temperature; Wine