Ângela Giovana Batista

Characterization of antioxidant polyphenols from Myrciaria jaboticaba peel and their effects on glucose metabolism and antioxidant status : A pilot clinical study

Brazilian berries, such as Myrciaria jaboticaba (jaboticaba), are good sources of polyphenols with a recognized function in oxidative stress attenuation proved in non-clinical studies. In the present study, the polyphenols profile and their contribution to the antioxidant capacity of the jaboticaba peel were analyzed using high-performance liquid chromatography (HPLC) with photodiode array (DAD), electrochemical (ECD), charged aerosol (CAD), and mass spectrometry (MS) detections. Anthocyanins, ellagitannins and gallotannins, ellagic acid and derivatives, and flavonols were found in jaboticaba. Anthocyanins were the phenolics found in higher concentrations. However, ellagitannins were the main contributors to the total antioxidant capacity. Moreover, the effect of jaboticaba peel intake on antioxidant and glucose parameters in a single-blind placebo-controlled crossover study was investigated. The serum antioxidant capacity was significantly higher when the subjects had consumed the test meal containing jaboticaba. Serum insulin decreased subsequent to the second meal at 4h after jaboticaba peel consumption.

Bioactive compounds of juices from two Brazilian grape cultivars

BACKGROUND Grape juice consumption may prevent several chronic diseases owing to the presence of phenolic compounds, which have an important role in the reduction of oxidative stress. This study investigated the polyphenol content and antioxidant activities of grape juices from two cultivars: BRS-Cora and Isabella. Total polyphenol content (TPC), anthocyanins, antioxidant capacity (oxygen radical absorbance capacity, ferric reducing antioxidant power and 1,1-diphenyl-2-picrylhydrazyl), and phenolic profile (high-performance liquid chromatography with diode array and fluorescence detection--HPLC-DAD-FLD) were determined. RESULTS BRS-Cora grape juice showed higher concentrations of total polyphenols and anthocyanins, as well as higher antioxidant potential, than those of Isabella grape juice. A significant positive correlation was found in TPC or anthocyanin contents when correlated with the remaining antioxidant assays. In addition, HPLC-DAD-FLD showed a higher total phenolic content in BRS-Cora grape juice compared to Isabella. CONCLUSION The present results show BRS-Cora as a promising cultivar for grape juice production with an improved functional potential.

Polyphenols, antioxidants, and antimutagenic effects of Copaifera langsdorffii fruit.

Copaifera langsdorffii (copaiba) is a Brazilian exotic fruit, poorly studied regarding its bioactive composition. The aim of this study was to determine bioactive compounds, antioxidant and antimutagenic activities of copaiba pulp. The samples were extracted with different solvents in order to analyze polyphenol compounds (Folin Ciocalteau and HPLC-DAD), total flavonoids (reaction with AlCl3) and antioxidant capacity (FRAP, ORAC, DPPH). The copaiba fruit showed high polyphenol content and antioxidant capacity. Phenolic compounds, such as gallic acid, epicatechin gallate, catechin, epicatechin and isoquercitrin, were identified in the copaiba pulp. Despite the antioxidant capacity, the highest dose of copaiba showed no antimutagenic effects in the in vivo study. The dose which showed antimutagenic activity was 100 mg kg(-1).

Passiflora edulis peel intake and ulcerative colitis: Approaches for prevention and treatment

Inflammatory bowel disease is a chronic relapsing disease that affects millions of people worldwide; its pathogenesis is influenced by genetic, environmental, microbiological, and immunological factors. The aim of this study was to evaluate the effects of short- and long-term Passiflora edulis peel intake on the antioxidant status, microbiota, and short-chain fatty acids formation in rats with 2,4,6-trinitrobenzenesulphonic acid-induced colitis using two “in vivo” experiments: chronic (prevention) and acute (treatment). The colitis damage score was determined using macroscopic and microscopic analyses. In addition, the antioxidant activity in serum and other tissues (liver and colon) was evaluated. Bifidobacteria, lactobacilli, aerobic bacteria and enterobacteria, and the amount of short-chain fatty acids (acetic, butyric, and propionic acids) in cecum content were counted. Differences in the colon damage scores were observed; P. edulis peel intake improved serum antioxidant status. In the treatment protocol, decreased colon lipid peroxidation, a decreased number of aerobic bacteria and enterobacteria, and an improvement in acetic and butyric acid levels in the feces were observed. An improvement in the bifidobacteria and lactobacilli was observed in the prevention protocol. These results suggested that P. edulis peel can modulate microbiota and could be used as source of fiber and polyphenols in the prevention of oxidative stress through the improvement of serum and tissue antioxidant status.

Jaboticaba (Myrciaria jaboticaba (Vell.) Berg.) peel improved triglycerides excretion and hepatic lipid peroxidation in high-fat-fed rats

OBJECTIVE: The aim of this study was to evaluate the influence of high-fat diets with 1%, 2%, and 4% freeze-dried jaboticaba peel on the serum, liver, and fecal lipid profile of obese rats. METHODS: Thirty male Sprague-Dawley rats were divided into 5 groups. Obesity was induced in four groups using a high-fat diet (35% lipids). One group was used as a high-fat diet control (High-fat group - HF). The other three high-fat-diet groups were given 1%, 2%, and 4% freeze-dried jaboticaba peel (High-Fat Jaboticaba - HFJ1, HFJ2, and HFJ4, respectively) in the last 40 experimental days. Blood and the liver were collected after 70 days of treatment and feces were collected in the last experimental week. Total cholesterol, triglycerides, and lipids were measured in the serum, liver, and dried feces. ffer in the experimental groups. HFJ2 group had the highest hepatic and fecal lipid contents compared with the group fed a diet with normal fat content (N), but low hepatic lipid peroxidation. HFJ4 group had the highest mean hepatic and fecal cholesterol levels. Hepatic triglyceride levels did not differ among the groups, and groups HFJ1 and HFJ4 presented the highest fecal triglyceride content. CONCLUSION: The amounts of jaboticaba peel used by this study did not protect against hepatic steatosis or undesired levels of other studied lipids, but it did increase fecal triglycerides. Lipid peroxidation in the liver decreased in the HFJ2 group.

Jaboticaba berry peel intake prevents insulin resistance-induced tau phosphorylation in mice

The hyperphosphorylation of microtubule-associated protein tau (tau) in the hippocampus can be caused by central and peripheral insulin resistance and these alterations are related to the development of tauopathies, such as Alzheimers disease. In this study, we used a high-fat diet to induce obesity and insulin resistance in adult Swiss mice and checked whether supplementation with Myrciaria jaboticaba berry peel for 10 weeks could improve insulin sensitivity, learning/memory performance, and prevent tau phosphorylation in the hippocampus. Furthermore, adipocytokines, inflammatory markers, and oxidative stress were assessed. Myrciaria jaboticaba peel has phenolic compounds (e.g., cyanidin, ellagic acid), dietary fiber and carotenoids, which contribute to great antioxidant capacity. Supplementation of the high-fat diet with 4% M. jaboticaba peel prevented fat weight gain and reduced peripheral insulin resistance. The treated group also showed lower tau phosphorylation in the hippocampus corroborating better learning/memory performance in the Morris water maze test. Maintenance of neuronal viability, lower levels of hippocampal inflammatory markers, and improved brain antioxidant defenses were also related to the consumption of M. jaboticaba peel. These findings contribute to a better understanding of how a high-fat diet supplemented with jaboticaba berry peel counteracts the impairment of cognitive functions caused by high-fat diet intake and diet-induced insulin resistance.