The Effect of Thiamine Concentration on the Antioxidative Activity Indices in Tea Extracts

Abstract

The aim of the study was to determine correlations between the concentration of thiamine in systems and indicators of the antioxidative activity of ethanol tea extracts in the presence of soybean oil. Variability of the thiamine form was assumed by comparison of the influence of thiamine hydrochloride or thiamine pyrophosphate and fermentation of ethanol tea extracts. The study provides practical knowledge about the antioxidative activity of ethanol tea extracts in products containing fat and thiamine. The study showed that all tea extracts exhibited higher antioxidative activity in the presence of thiamine amounts of 0.1 and 0.8 mg/100 g. The antioxidative activity of ethanol tea extracts was significantly reduced when the concentrations were higher than the natural level for foods (over 1.0 mg/100 g). The systems containing white tea extract were the most vulnerable, whereas those with black tea were the least vulnerable. The presence of thiamine pyrophosphate in the system was more strongly correlated with reduced activity of the extracts than the presence of thiamine hydrochloride.

Thiamine in Lipid Systems vs. the Antioxidant Activity of Epigallocatechin Gallate and Caffeine

“…The results of our study are consistent with the findings of earlier research on the antioxidant activity of tea components [35,44,52,53]. The antioxidant activity of green, oolong, and white tea has been shown [44,[54][55][56].…”

“…Our preliminary studies [43,44] have shown that the addition of tea extracts has increased the oxidative stability of fat and thus has reduced the loss of thiamine. This analysis has shown the greatest protective effect of white and green tea extracts, which has strongly correlated with the highest antioxidant efficiency.…”

The Changes in Antioxidant Activity of Selected Flavonoids and Caffeine Depending on the Dosage and Form of Thiamine

“…However, in systems containing TH or TP in amounts exceeding 6.0 mg/100 g there was a statistically significant decrease in the antioxidant properties of all tested compounds. This direction is confirmed by previous studies on ethanol tea extracts [ 62 ]. In these studies, the highest negative correlation between the higher (above 3 mg/100 g) quantity of thiamine and the antioxidant activity of white and green tea extract was confirmed [ 62 , 64 ].…”

“…This direction is confirmed by previous studies on ethanol tea extracts [ 62 ]. In these studies, the highest negative correlation between the higher (above 3 mg/100 g) quantity of thiamine and the antioxidant activity of white and green tea extract was confirmed [ 62 , 64 ]. This may be due to the fact that the antioxidant activity of flavonoids, including EGCG, depends on both chemical structure and environmental conditions [ 65 ].…”

“…Similar trends were found in systems containing ethanolic tea extracts. Previous studies confirmed that at thiamine concentration in the range 0.1 and 0.8 mg/100 g there was increase in the chelating properties and reducing power indices and an increase in the protection factor of ethanol tea extracts [ 62 ]. A similar trend was found for the free radicals scavenging indices of the tested components.…”