Revisiting the chemistry of apple pomace polyphenols

Hot water is an easily implementable process for polyphenols extraction. To evaluate the effect of this process on apple pomace, the overall polyphenolic composition was assessed before and after hot water extraction, followed by extractions with aqueous/organic solutions. As determined by UHPLC-DAD, flavan-3-ols were the main apple native polyphenols. Their amount decreased 50% after hot water extraction, while the other classes remained unchanged. Dihydrochalcones and hydroxycinnamic acid oxidation products, were also observed, alongside with non-extractable oxidised procyanidins that represented more than 4-fold the amount of native apple polyphenols in the pomace. Microwave superheated-water extraction of the insoluble cell wall material in water/acetone solutions and the high amounts of polyphenols that were insoluble in water/ethanol solutions suggested that oxidised procyanidins could be covalently linked to polysaccharides. These complexes represented up to 40% of the available polyphenols from apple pomace, potentially relevant for agro-food waste valuation.publishe

Identification of structural features of condensed tannins that affect protein aggregation

A diverse panel of condensed tannins was used to resolve the confounding effects of size and subunit composition seen previously in tannin-protein interactions. Turbidimetry revealed that size in terms of mean degree of polymerisation (mDP) or average molecular weight (amw) was the most important tannin parameter. The smallest tannin with the relatively largest effect on protein aggregation had an mDP of ~7. The average size was significantly correlated with aggregation of bovine serum albumin, BSA (mDP: r=-0.916; amw: r=-0.925; p<0.01; df=27), and gelatin (mDP: r=-0.961; amw: r=-0.981; p<0.01; df=12). The procyanidin/prodelphinidin and cis-/trans-flavan-3-ol ratios gave no significant correlations. Tryptophan fluorescence quenching indicated that procyanidins and cis-flavan-3-ol units contributed most to the tannin interactions on the BSA surface and in the hydrophobic binding pocket (r=0.677; p<0.05; df=9 and r=0.887; p<0.01; df=9, respectively). Circular dichroism revealed that higher proportions of prodelphinidins decreased the apparent α-helix content (r=-0.941; p<0.01; df=5) and increased the apparent β-sheet content (r=0.916; p<0.05; df=5) of BSA

Neutral sugar side chains of pectins limit interactions withprocyanidins

International audienc

Neutral sugar side chains of pectins limit interactions with procyanidins

International audienc

Comparison of motion sensor and heart rate monitor for assessment of physical activity intensity in stroke outpatient rehabilitation sessions: an observational study

Objective: To compare the estimation of time spent on 4 categories of physical activity intensity (sedentary behaviour, light physical activity, moderate physical activity, and vigorous physical activity) between a motion sensor and a heart rate monitor during a stroke outpatient rehabilitation session. Design: A multicentre cross-sectional observational study. Subjects/Patients: Participants with stroke (> 6 months) undergoing outpatient rehabilitation sessions. Methods: Participants wore the SenseWear Armband motion sensor and the Polar H10 heart rate monitor during 2 rehabilitation sessions. The times estimated by each device were compared using a generalized linear mixed model and post-hoc tests. Results: Ninety-nine participants from 29 clinics were recruited and data from 146 sessions were included in the analysis. The estimated times depended on the devices and the physical activity intensity category (F = 135, p < 0.05). The motion sensor estimated more time spent in sedentary behaviour and less time spent in moderate physical activity and vigorous physical activity than the heart rate monitor. Conclusion: The motion sensor and heart rate monitor provide different estimates of physical activity intensity during stroke rehabilitation. Further research is needed to establish the most appropriate device for each physical activity category

Interactions between pectic compounds and procyanidins are influenced by methylation degree and chain length

International audienc

Comparison of motion sensor and heart rate monitor for assessment of physical activity intensity in stroke outpatient rehabilitation sessions: an observational study

International audienceObjective: To compare the estimation of time spent on 4 categories of physical activity intensity (sedentary behaviour, light physical activity, moderate physical activity, and vigorous physical activity) between a motion sensor and a heart rate monitor during a stroke outpatient rehabilitation session.Design: A multicentre cross-sectional observational study.Subjects/Patients: Participants with stroke (&gt; 6 months) undergoing outpatient rehabilitation sessions.Methods: Participants wore the SenseWear Armband motion sensor and the Polar H10 heart rate monitor during 2 rehabilitation sessions. The times estimated by each device were compared using a generalized linear mixed model and post-hoc tests.Results: Ninety-nine participants from 29 clinics were recruited and data from 146 sessions were included in the analysis. The estimated times depended on the devices and the physical activity intensity category (F= 135, p &lt; 0.05). The motion sensor estimated more time spent in sedentary behaviour and less time spent in moderate physical activity and vigorous physical activity than the heart rate monitor.Conclusion: The motion sensor and heart rate monitor provide different estimates of physical activity intensity during stroke rehabilitation. Further research is needed to establish the most appropriate device for each physical activity category

Impact of processing on the non-covalent interactions between procyanidin and apple cell wall

International audienc