This study aimed investigate the chronic effect of orange juice consumption on gut microbiota and in the bioavailability of flavanones and metabolites by feces, blood and urine analysis.

Non-randomized study with interrupted time series and open-label, in which women were enrolled and advised to not consumed foods containing prebiotic, probiotic and fibers, and citrus fruits and beverages during 30 days before of intervention (n=10; BMI 23.8 kg/m2; 28 years). After 30 days, the participants will consume during 60 days 300 mL of orange juice daily. After 60 days of orange juice intervention, the participants will be submitted to 30 days of washout. Samples of blood, urine and feces will collect in five different occasions (baseline, 30 day, 60 day, 90 day, and 120 day) in order to evaluate the prebiotic effect of orange juice on gut microbiota and in the bioavailability of its flavanones. The recruitment process began in September 2016 and the intervention was carried out from October 2016 to February 2017, and the data analysis will start in February 2017. The sample number took into account variances on blood hesperitin levels with a type I error α = 0.05 and a type II error β = 0.2 (80% power) (Silveira et al., 2015). The minimum sample size should have six individuals into the same group. Considering an approximately 15% dropout rate, the final sample size of study was constituted by 10 women. Primary endpoint is the changes in total bacteria population (Lactobacillus spp., Bifidobacterium spp., and reduction of Clostridium spp.) that can result in increased of butyric, acetic, and propionic acid concentrations, and reduction of ammonium production. Secondary endpoint is enhancement of bioavailability of flavanones (hesperitin, naringenin) and metabolites in the blood, urine and feces. Kolmogorov Smirnov and Levene test will be used to assess the normality and homogeneity of data, respectively. One-way analysis of variance (ANOVA) will be apply to determine the intervention effect over the time 0, 30 day, 60 day, 90 day, and 120 day). P significance was set up ≤ 0.05.

Inclusion Criteria:

Healthy women BMI 18.5 - 29.9 kg/m2.

Exclusion Criteria:

Gastrointestinal diseases Pregnant women Regular use of medications Dietary restrictions, vegetarian diet, macrobiotic, etc. Use of vitamins or dietary supplements Use of probiotics or prebiotics in the last 3 months and antibiotics in the last 6 months.

There is still no decision regarding if the individual participant data (IPD) will be available to other researchers.