Combined effect of starch/montmorillonite coating and passive MAP in antioxidant activity, total phenolics, organic acids and volatile of fresh-cut carrots.

This work evaluates fresh-cut carrots (FCC) coated with montmorillonite (MMT) subjected to passive modified atmosphere packaging. Carrots were sanitized, cooled, peeled and sliced. Half of the FCC were coated with MMT nanoparticle film and the other half were not. All FCCs were packed in a polypropylene rigid tray, covered with a polypropylene rigid lid or sealed with polyethylene + propylene film, in four treatments (RL, rigid lid; RLC, rigid lid + coating; ST, sealed tray; STC, sealed tray + coating). FCCs were stored at 4 °C and were analyzed weekly for 4 weeks (total antioxidant activity by 2,2-diphenyl-1-picryl hydrazyl method and the ß-carotene/linoleic acid, phenolic compounds, organic acids and volatile compounds). The use of coating film with starch nanoparticles and a modified atmosphere leads to the preservation of the total antioxidant activity, the volatile and organic acids of FCC.

Monitoring of immunological parameters in adolescent basketball athletes during and after a sports season.

The objective of the present study was to monitor the immunological and hormonal responses and the occurrence of upper respiratory symptoms in adolescent basketball athletes during the different stages of a sports season. Anthropometric measures, biochemical analyses (interleukin-6, interleukin-10, tumour necrosis factor-alpha, C-reactive protein, testosterone and cortisol), neuromuscular evaluations (standing vertical jumping ability, agility and estimated VO2max) and leukocyte counts were performed at four moments: 72 h before the season (-72 h); before the season (Pre-season); after six weeks, at the end of the preparatory period (Preparatory); and after 20 weeks, at the end of the competitive period (Competitive). Also, the occurrence of upper respiratory symptoms was collected weekly during all stages of the season. There were significant increases in monocytes, cortisol, tumour necrosis factor-alpha and C-reactive protein at the Competitive moment as compared to the Pre-season. In addition, interleukin-10 decreased at the Competitive moment as compared to the Pre-season. Occurrence of upper respiratory symptoms demonstrated increases (38%) during the competitive period as compared to the preparatory. These results suggest that periods of training and competition could increase the occurrence of upper respiratory symptoms in adolescent athletes and this may be due to the unwanted effects of an inflammatory process in response to the excessive stress of training and competition.

Immune responses, upper respiratory illness symptoms, and load changes in young athletes during the preparatory period of the training periodization.

OBJECTIVE: The aim of this study was to investigate the immunological responses and the association between variation in exercise load and self-reported occurrence of upper respiratory illness (URI) symptoms in young basketball athletes. MATERIALS AND METHODS: The sample was composed of twelve young male athletes aged 12.7 ± 0.6 years, with a height of 170 ± 10 cm, body mass of 57.6 ± 12.6 kg, and fat-free mass of 18.7 ± 5.9%. Daily training and occurrences of URI symptoms were recorded. Blood samples were collected at baseline (M1) and after 8 weeks (M2) of the preparatory period of periodization training to measure total and differential leukocyte counts, serum interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). RESULTS: There was a significant decrease in monocytes at M2 compared to M1 (P = 0.004). There were no significant alterations in total leukocytes (P = 0.07), neutrophils (P = 0.07), or lymphocytes (P = 0.09). No significant changes in plasma concentrations of TNF-α (P = 0.30) or IL-6 (P = 0.90) were found. The weekly load from week 6 was higher when compared with weeks 1, 2, 4, and 8 (P < 0.05), and week 8 was the lowest when compared with week 5 (P < 0.05). Self-reported URI incidences were highest at weeks 1 and 2. CONCLUSION: Variations in weekly training load during the preparatory period were not correlated with changes in self-reported occurrence of URI incidences, suggesting that young athletes may have an attenuated response to exercise-induced perturbations to the immune system.