The objective of this study was to evaluate changes in color, betalain content, browning index, viscosity, physical stability, microbiological growth, antioxidant content and antioxidant activity of purple cactus pear juice during storage after thermoultrasonication at 80% amplitude level for 15 and 25 min in comparison with pasteurized juice. Thermoultrasound treatment for 25 min increased color stability and viscosity compared to treatment for 15 min (6.83 and 6.72 MPa, respectively), but this last parameter was significantly lower (p<0.05) compared to the control and pasteurized juices (22.47 and 26.32 MPa, respectively). Experimental treatment reduced significantly (p<0.05) sediment solids in juices. Total plate counts decreased from the first day of storage exhibiting values of 1.38 and 1.43 logCFU/mL, for 15 and 25 min treatment, respectively. Compared to the control, both treatments reduced enterobacteria counts (1.54 logCFU/mL), and compared to pasteurized juice decreased pectinmethylesterase activity (3.76 and 3.82 UPE/mL), maintained high values of ascorbic acid (252.05 and 257.18 mg AA/L) and antioxidant activity (by ABTS: 124.8 and 115.6 mg VCEAC/100 mL; and DPPH: 3114.2 and 2757.1 μmol TE/L). During storage thermoultrasonicated juices had a minimum increase in pectinmethylesterase activity (from day 14), and exhibited similar total plate counts to pasteurized juice. An increase of phenolic content was observed after 14 days of storage, particularly for treatment at 80%, 25 min, and an increase in antioxidant activity (ABTS, DPPH) by the end of storage.

The purpose of the present study was to determine the optimal ultrasound conditions (amplitude level and time) for the extraction of cactus pear seed oil with the highest antioxidant activity using a closed system. Seed oil was analyzed for yield, antioxidant activity by ABTS and DPPH, and antimicrobial activity. Conventional extraction methods were assessed for comparison. Amplitude level significantly affected antioxidant activity in linear terms (p< 0.0001 DPPH andp< 0.001 ABTS, resp.) so, at lower amplitudes, the higher antioxidant activity was achieved. The optimum ultrasound extraction conditions were of 78% amplitude for 10 min and yielded antioxidant activity values of 66.25 mg AAE/100 g and 289 µmol TE/100 g for ABTS and DPPH, respectively. Compared with conventional extraction methods, ultrasound exhibited lower oil yield and antioxidant activity but had the potential to achieve comparable results if multiple ultrasound extractions are performed in the time needed by conventional methods. Seed oils showed similar antimicrobial activity despite the extraction method and were more effective againstEscherichia coli. The results demonstrated that ultrasound can be an alternative extraction method of seed oils from fruits such as cactus pear.

Cardiovascular diseases are part of the highly preventable chronic diseases associated with changes in lifestyle. Within them, physical activity, low-fat and high-fiber diets are distinguished as the main support for prevention, even when supplementation with nutraceuticals has become a very common practice. Fifty-two young sedentary men with excess body weight (body mass index (BMI) ≥ 25 kg·m⁻²) were enrolled in a randomized-crossover controlled trial [six weeks of a systematic physical exercise with Spirulina maxima or placebo supplementation (4.5 g·day⁻¹)]. Body composition, blood lipid profile, and maximal oxygen uptake were determined pre/post intervention. Pairwise comparisons showed a significant improvement (p < 0.01) on blood lipid profile in the group of exercise plus Spirulina maxima. Moreover, correlations of absolute changes of BMI, body fat percentage, blood lipids and maximal oxygen uptake were statistically significant (p < 0.01). These results indicate that the Spirulina maxima supplementation could be acting in a synergistic way with exercise due to the enhanced effects on body composition, cardiorespiratory fitness, and blood lipid profile. This phenomenon should be considered to reduce risk of cardiovascular disorders. Trial registration: Clinical Trials, NCT02837666 (July 19, 2016).