Physico-chemical characterization and antioxidant capacity of the colombian berry (Vaccinium meridionale Swartz) with a high-polyphenol content: potential effects in people with metabolic syndrome

Abstract

Colombian berry (agraz) has demonstrated a high antioxidant content in vitro. On the present study, it was elaborated and characterized an agraz nectar, designed a placebo with similar physicochemical and sensorial characteristics of the agraz nectar, but without polyphenols; and evaluated their antioxidant capacity both in vitro and in vivo in adults with cardiovascular risk factors. The polyphenolic concentration of the agraz nectar and its antioxidant capacity was superior than other reported for this fruit. A high content of total cyanidins was observed in the freeze-dried agraz, but not delphinin was detected by HPLC. For the intervention study, sixty-six subjects, with at least three cardiometabolic risk factors, consumed agraz nectar or placebo daily during 4 weeks each, separated by a 4-week washout period. Total phenol concentration and antioxidant capacity in the participants' serum were not statistically different after consuming agraz nectar and placebo. However, women increased significantly their serum DPPH scavenging capacity after consuming agraz nectar, compared to placebo. This is one of the first studies showing data about the effects of this colombian berry on the antioxidant capacity in people with metabolic syndrome.

Evaluation of Agraz Consumption on Adipocytokines, Inflammation, and Oxidative Stress Markers in Women with Metabolic Syndrome

“…The placebo was designed to match the agraz in terms of look, feel, taste, and macronutrients, but without polyphenols. The composition of agraz nectar and placebo is presented in Table 1 and it has been previously described [ 40 ]. Following 4 weeks of consuming agraz or placebo, participants underwent a 4-week washout period and were allocated to the alternate treatment for the next 4 weeks.…”

Differential Effects of Agraz (<i>Vaccinium meridionale</i> Swartz) Consumption in Overweight and Obese Women with Metabolic Syndrome

“…In 2018, Torres et al, showed that 21 days of osmodehydrated Andean berry consumption in overweight subjects caused reductions of some CVRF like blood pressure, BMI and WC [25]. Previously, we reported beneficial effects after 4-weeks of agraz consumption in this same group of women with MetS, with increases in TAC [26] and reduction in DNA oxidative damage [27]. However, there are limited studies evaluating the effect of consumption of a polyphenol-rich beverage of agraz on OxS markers and antioxidant capacity comparing people with different BMI classification.…”

“…In obese women, there was a tendency to increase serum TAC measured by DPPH scavenging capacity by 18.2% after agraz consumption, compared to placebo. Recently, we reported an increase in serum antioxidant status by 19% with this method after 30 days of agraz consumption, in the whole group of women with MetS [26]. This could indicate there was a greater neutralization of DPPH radicals in serum through donation of an electron and/or a hydrogen by antioxidant molecules (i.e.…”

“…Women were assigned through an alternating quasi-randomization allocation method, to consume over 4 weeks either a freeze-dried agraz powder dissolved in 200 mL of water (containing 1027.97 ± 41.99 mg gallic acid equivalents /L of total phenols) or 200 mL of placebo (with sensorial and physicochemical characteristics of the agraz beverage, but devoid of any polyphenols). Both beverages were prepared and characterized by food engineers of the University of Antioquia as previously described [26]. There was a 4-week washout between both periods, in which neither agraz nor placebo were consumed.…”

“…Serum TAC was measured through several methods: 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) was determined via a modified method described by Re, et al (1999) [35]; ferric reducing ability of plasma (FRAP) was measured using the modified method of Benzie and Strain (1996) [36]; oxygen radical absorbance capacity (ORAC) and 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) were measured following the methodology reported by Quintero et al [26].…”