Effect of Chokeberry Juice on N-Nitrosodiethylamine-Induced Rat Liver Carcinogenesis.

Because humans commonly consume chokeberry, especially as a nutritional supplement, it must be checked to determine whether its excessive ingestion can cause adverse effects, in particular, in the case of simultaneous exposure to some xenobiotics. From this point of view, we examined the impact of long-term cotreatment of rats with chokeberry juice and hepatic carcinogen N-nitrosodiethylamine (NDEA) on oxidative damages and neoplastic lesions in the liver of rats. Daily exposure to chokeberry juice in a concentration of 10 g/kg feed via diet for 13 wk led to an intensified hepatotoxic effect of NDEA (0.01% in drinking water for 13 wk), as evidenced by changes in histopathological architecture of liver tissue, increased lipid peroxidation, protein carbonyl formation, and DNA degradation. Moreover, we noticed an increase in relative liver weight and a decrease in body weight in this group in comparison to NDEA-alone treated animals. Chokeberry juice applied alone did not cause any adverse effects in rats. On the basis of these findings, it can be concluded that high doses and longterm administration of chokeberry juice may enhance tumor-promoting action of some chemical carcinogens.

Assessment of colour changes during storage of elderberry juice concentrate solutions using the optimization method.

BACKGROUND: Elderberries are a source of dietary supplements and bioactive compounds, such as anthocyanins. These dyes are used in food technology. The aim of the study was to assess the changes in colour parameters, anthocyanin contents and sensory attributes in solutions of elderberry juice concentrates during storage in a model system and to determine predictability of sensory attributes of colour in solutions based on regression equations using the response surface methodology. METHODS: The experiment was carried out according to the 3-level factorial design for three factors. Independent variables included pH, storage time and temperature. Dependent variables were assumed to be the components and colour parameters in the CIE L*a*b* system, pigment contents and sensory attributes. RESULTS: Changes in colour components X, Y, Z and colour parameters L*, a*, b*, C* and h* were most dependent on pH values. Colour lightness L* and tone h* increased with an increase in experimental factors, while the share of the red colour a* and colour saturation C* decreased. The greatest effect on the anthocyanin concentration was recorded for storage time. Sensory attributes deteriorated during storage. The highest correlation coefficients were found between the value of colour tone h* and anthocyanin contents in relation to the assessment of the naturalness and desirability of colour. A high goodness-of-fit of the model to data and high values of R2 for regression equations were obtained for all responses. CONCLUSIONS: The response surface method facilitates optimization of experimental factor values in order to obtain a specific attribute of the product, but not in all cases of the experiment. Within the tested range of factors, it is possible to predict changes in anthocyanin content and the sensory attributes of elderberry juice concentrate solutions as food dye, on the basis of the lack of a fit test. The highest stability of dyes and colour of elderberry solutions was found in the samples at pH 3.0, which confirms the advisability of using an anthocyanin preparation to shape the colour of high-acidity food products, such as fruit fillings, beverages,desserts.

Antioxidant effects of gastrointestinal digested purple carrot extract on the human cells of colonic mucosa.

Purple carrot (PC) is a potential dietary constituent, which represents a valuable source of antioxidants and can modulate the reactive oxygen species (ROS) level in the gastrointestinal tract. Antioxidant capacity of a PC extract subjected to digestion process simulated in the artificial alimentary tract, including the stomach, small intestine and colon, was analyzed in normal human cells of colon mucosa. Results indicated that the extract obtained upon passage through the gastrointestinal tract, which could come into contact with the colonic cells in situ, was less potent than the extract, which was not subjected to digestion process. Digested PC extract exhibited intracellular ROS-inhibitory capacity, with 1mg/mL showing the ROS clearance of 18.4%. A 20.7% reduction in oxidative DNA damage due to colon mucosa cells' treatment with digested PC extract was observed. These findings indicate that PC extract is capable of colonic cells' protection against the adverse effects of oxidative stress.

Purple carrot anthocyanins suppress lipopolysaccharide-induced inflammation in the co-culture of intestinal Caco-2 and macrophage RAW264.7 cells.

This study was designed to evaluate the anti-inflammatory effects of purple carrot anthocyanins (PCA) with respect to gut inflammation, simulated in a co-culture system consisting of intestinal epithelial Caco-2 cells and RAW264.7 macrophages. The obtained results indicated that PCA extract down-regulates the mRNA expression of proinflammatory interleukins Il-1ß (↓91%) and Il-6 (↓69%) as well as inflammatory mediators, such as cyclooxygenase-2 (Cox-2) and inducible nitric oxide synthase (iNos), in lipopolysaccharide-activated RAW264.7 cells. The decrease in the generation of prostaglandin E2 (↓48%) and nitric oxide (↓26%) was observed as a result of the inhibition of Cox-2 (↓25%) and iNos (↓12%) mRNA expressions, respectively. Moreover, the PCA reduced mRNA expression (↓40%) and production (↓17%) of IL-8 in intestinal cells. The anti-inflammatory effect of PCA was contributed to the protection of the intestinal barrier, which was disrupted upon the stimulation of macrophages. These findings may provide preliminary justification for the use of PCA in further studies focused on the prevention and therapy supporting the conventional treatment of inflammatory bowel diseases.

The effect of pre-treatment and modified atmosphere packaging on contents of phenolic compounds and sensory and microbiological quality of shredded celeriac.

BACKGROUND: The aim of this study was to determine the effect of washing (4 °C, 120 s) or soaking (4 °C, 600 s) of shredded celeriac in tap water on changes in contents of phenolic compounds, including furanocoumarins, and sensory and microbiological quality during 12 days of storage. The product was packaged in air or modified atmosphere containing 2/10/88 kPa O2/CO2/N2. RESULTS: The applied pre-treatment consisting of washing or soaking of shredded celeriac in water resulted in decreases in 8-methoxypsoralen content by approximately 50 and 70% respectively and phenolic content by 30% compared with samples that were not subjected to pre-treatment. During storage of shredded celeriac, a further significant (P ≤ 0.05) reduction in phenolic compounds and an approximately 2.5-fold increase in the total content of furanocoumarins were found. The application of modified atmosphere packaging had a significant effect on the maintenance of good sensory and microbiological quality of the tested product. CONCLUSION: Modified atmosphere packaging of shredded celeriac not subjected to pre-treatment made it possible to obtain a product with good sensory and microbiological quality and the highest content of phenolic compounds. The level of furanocoumarins recorded in the tested product does not constitute a health hazard.