ABSTRACT
The article presents the results of study of the effect of polyphenol-rich materials obtained from grapes on the clinical symptoms, activity of non-specific proteases, and parameters of lipid peroxidation (LPO) of blood of rats with fructose model of metabolic syndrome (MS). White male rats (n=54, with initial body weight of 190-210 g) were randomly divided into five groups: control and 4 experimental groups. Body weight, circumference of the abdomen, blood serum level of glucose, total cholesterol, triglycerides and high density (HDL) lipoproteins were monitored in all animals in dynamics. Also non-specific proteases and their inhibitors were evaluated in rat blood by enzymatic methods, lipid peroxidation profile (malondialdehyde and caeruloplasmin blood serum level, superoxide dismutase blood activity) - by spectrophotometric methods. Modeling of the MS (10% fructose in drinking water) within 8 weeks resulted in statistically significant increase in body mass, abdominal adipose tissue, the activity of elastase-like (ELA) and trypsin-like (TLA) proteinases (20 and 18% respectively), the level of secondary products of LPO (50%), and decrease in activity of superoxide dismutase (15%) compared with the parameters of intact animals. The use of polyphenol-rich materials obtained from grapes with a total content of 1; 1,1 and 4 mg of phenolic compounds (in 0.05 ml) at MS for 4 weeks contributed regression the key clinical signs of MS: significant decrease of glucose and triglyceride levels against the background of increasing the HDL cholesterol were observed. The polyphenol-rich materials obtained from grapes influenced positively on the proteolytic profile (decreased TLA and ELA by 20% at the maximum dosage), contributed to the increase of the level of acid-stable protease inhibitors (by 21%), and reduced the amount of secondary products of LPO (by 34%). The dose-dependent effect of the amount of polyphenol components contained in food concentrates has been revealed.
ABSTRACT
Experimental data on the antioxidant activity of grape juice, grape concentrates and wine from grapes of Cabernet Sauvignon, Merlot and Saperavi from Crimea and Krasnodar regions was presented. Flavonoids are presented in the form of glycosides of such anthocyanins as delphinidin, malvidin, cyanidin, petunidin, peonidin and also by quercetin and its glycoside, (+)-D-catechin and (-)-epicatechin. Oligomeric procyanidins, which are condensed catechol units (2-6) soluble in water, are presented in significant amounts, and polymeric procyanidins with the amount catechin units greater than 7, insoluble in water, constituted the bulk of polyphenols od wine and concentrates from red grapes (no juice). Among non-flavonoid polyphenols hydroxybenzoic (gallic, syringic) and hydroxycinnamic (caftaric, cautaric) acids are identified, the relative content of which in the amount of polyphenols in the juice is maximum, and minimum is in concentrates. It was found that antioxidant activity for all products in standard Trolox method can be estimated by the equation: Y = 0.53627+0.1395X+0.080439X2-0.00064708X3, with a correlation coefficient r = 0.9952; where: Y--antioxidant activity, g/dm3 by Trolox method; X--mass concentration of phenolic substances on the Folin-Ciocalteu, g/dm3. The equation is valid for Y = 0.76-196.22; X = 1.0-82.67. The results of biological testing of wines Cabernet Sauvignon, Merlot, Saperavi and polyphenol concentrates from grape on the biological model of bioluminescent bacteria Photobacterium leiognathi Sh1 demonstrated the applicability of bioassay to assess the antioxidant activity, which correlates well with the polyphenols content and antioxidant activity by trolox method.