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1.
Ultrason Sonochem ; 39: 58-65, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28732983

ABSTRACT

The current procedure of rapeseed oil extraction is based on a first extraction step by pressing followed by a second extraction step with hexane. This solvent being toxic for the users, the consumers and the environment, its use could be forbidden within the coming years. Stimulated by a stringent regulation, the research activity for the replacement of toxic solvents shows a significant development. The aim of this study was to select alternative solvent to hexane such as ethanol or isopropanol, and, to adjust the oil extraction process by developing an ultrasound assisted method. The objective was to reach a comparable efficiency but also to enhance the oil quality. When applied to isopropanol, the ultrasound assisted extraction method has shown promising results, and comparable to those obtained with hexane (oil yield of 80% for hexane and 79% for isopropanol at optimum extraction conditions (20min of ultrasound pretreatment followed by 2h of additional solid/liquid extraction)). Conversely, in studied conditions, ethanol did not seem to be an appropriate alternative solvent to hexane as the extraction yields obtained by using this solvent were quite low.


Subject(s)
Brassica rapa/chemistry , Chemical Fractionation/methods , Plant Oils/isolation & purification , Solvents/chemistry , Ultrasonic Waves , Green Chemistry Technology
2.
Physiol Int ; 104(1): 77-90, 2017 Mar 01.
Article in English | MEDLINE | ID: mdl-28361573

ABSTRACT

The aim of this study was to investigate the effect of time-of-day on oxidative stress, cardiovascular parameters, muscle damage parameters, and hormonal responses following the level-1 Yo-Yo intermittent recovery test (YYIRT). A total of 11 healthy subjects performed an intermittent test (YYIRT) at two times-of-day (i.e., 07:00 h and 17:00 h), with a recovery period of ≥36 h in-between, in a randomized order. Blood samples were taken at the rest (baseline) and immediately (post-YYIRT) after the YYIRT for measuring oxidative stress, biochemical markers, and hormonal response. Data were statistically analyzed using one-way and two-way repeated measures ANOVA and Bonferroni test at p < 0.05. Observed power (α = 0.05) and partial eta-squared were used. Our results showed that oxygen uptake (VO2max), maximal aerobic speed, and the total distance covered tended to be higher in the evening (17:00 h). There was also a main effect of time-of-day for cortisol and testosterone concentration, which were higher after the YYIRT in the morning (p < 0.05). The heart rate peak and the rating of perceived exertion scales were lower in the morning (p < 0.05). However, the plasma glucose (p < 0.01), malondialdehyde, creatine kinase (p < 0.01), lactate dehydrogenase (p < 0.05), high-density lipoprotein (p < 0.01), total cholesterol (p < 0.01), and triglycerides (p < 0.05) were higher after the YYIRT in the evening. Low-density lipoprotein, systolic blood pressure, diastolic blood pressure, and lactate levels (p > 0.05) were similar for the morning and evening test. In conclusion, our findings suggest that aerobic performance presents diurnal variation with great result observed in the evening accompanied by an improvement of hormonal, metabolic, and oxidative responses. These data may help to guide athletes and coaches and contribute to public health recommendations on exercise and muscle damage particularly in the competitive periods.


Subject(s)
Circadian Rhythm , Exercise Test/methods , Exercise/physiology , Hemodynamics , High-Intensity Interval Training , Hydrocortisone/blood , Muscle Contraction , Muscle, Skeletal/metabolism , Oxidative Stress , Testosterone/blood , Analysis of Variance , Biomarkers/blood , Blood Pressure , Healthy Volunteers , Heart Rate , Humans , Malondialdehyde/blood , Muscle Strength , Oxygen Consumption , Perception , Predictive Value of Tests , Recovery of Function , Running , Thiobarbituric Acid Reactive Substances/metabolism , Time Factors , Young Adult
3.
Bioresour Technol ; 237: 11-19, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28411049

ABSTRACT

In this study, ultrasound (US) and high voltage electrical discharges (HVED) were combined with chemical treatments (soda or organosolv) for rapeseed straw delignification. Delignification was improved by both physical pretreatments. US increased the extractability of hemicelluloses and HVED induced a partial degradation of cellulose. Best synergies were observed for HVED-soda and US-organosolv treatments. The obtained lignin fractions were characterized with 13C NMR and 2D 1H-13C HSQC. It was observed that the physical treatments affected the syringyl/guaiacyl (S/G) ratios. The values of S/G were ≈1.19, 1.31 and 1.75 for organosolv, HVED-organosolv and US-organosolv processes, suggesting recondensation reactions. The lignin fractions obtained from HVED-organosolv treatment contained less quantity of p-coumaric acid and ferulic acid as compared to those extracted by US-organosolv. Thermogravimetric analysis (TGA) revealed a better heat resistance of physically extracted lignins as compared to the control. The enzymatic digestibility increased by 24.92% when applying HVED to mild organosolv treatment.


Subject(s)
Brassica rapa , Electricity , Lignin , Cellulose , Coumaric Acids , Propionates
4.
J Appl Microbiol ; 120(1): 152-64, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26497010

ABSTRACT

AIMS: In this study, pulsed-electric fields (PEF) and high-voltage electrical discharges (HVED) are proposed as new techniques for the microbial stabilization of red wines before bottling. The efficiency of the treatment was then evaluated. METHODS AND RESULTS: PEF and HVED-treatments have been applied to wine for the inactivation of Oenococcus oeni CRBO 9304, O. oeni CRBO 0608, Pediococcus parvulus CRBO 2.6 and Brettanomyces bruxellensis CB28. Different treatment times (1, 2, 4, 6, 8 and 10 ms) were used at 20 kV cm(-1) for the PEF treatments and at 40 kV for the HVED treatments, which correspond to applied energies from 80 to 800 kJ l(-1) . The effects of the treatments on the microbial inactivation rate and on various characteristics of red wines (phenolic composition, chromatic characteristics and physico-chemical parameters) were measured. CONCLUSIONS: The application of PEF or HVED treatments on red wine allowed the inactivation of alteration yeasts (B. bruxellensis CB28) and bacteria (O. oeni CRBO 9304, O. oeni CRBO 0608 and P. parvulus CRBO 2.6). The electric discharges at 40 kV were less effective than the PEF even after 10 ms of treatments. Indeed, 4 ms of PEF treatment at 20 kV cm(-1) were sufficient to inactivate all micro-organisms present in the wines. Also, the use of PEF had no negative impact on the composition of wines compared to the HVED treatments. Contrary to PEF, the phenolics compounds were degraded after the HVED treatment and the physico-chemical composition of wine were modified with HVED. SIGNIFICANCE AND IMPACT OF THE STUDY: PEF technology seems to be an interesting alternative to stabilize microbiologically wines before bottling and without modifying their composition. This process offers many advantages for winemakers: no chemical inputs, low energy consumption (320 kJ l(-1) ), fast (treatment time of 4 ms) and athermal (ΔT ≈ 10°C).


Subject(s)
Brettanomyces/radiation effects , Microbial Viability/radiation effects , Oenococcus/radiation effects , Pediococcus/radiation effects , Wine/microbiology , Electricity , Phenols/analysis , Wine/analysis
5.
Rev Med Interne ; 35(9): 595-600, 2014 Sep.
Article in French | MEDLINE | ID: mdl-24797142

ABSTRACT

SAPHO (synovitis, acne, pustulosis, hyperostosis, osteitis) syndrome is a rare entity characterized by the association of heterogeneous osteoarticular and cutaneous manifestations that have for common denominator an aseptic inflammatory process. The etiopathogeny of this disease is still a matter of debate. Although it has been related to the spondylarthritis family, an infectious origin is suggested. Diagnosis is based on the presence of at least one of the three diagnostic criteria proposed by Kahn. The treatment includes NSAIDs, antibiotics, corticosteroids, methotrexate and more recently the bisphosphonates and the TNFα inhibitors.


Subject(s)
Acquired Hyperostosis Syndrome , Acquired Hyperostosis Syndrome/diagnosis , Acquired Hyperostosis Syndrome/epidemiology , Acquired Hyperostosis Syndrome/etiology , Acquired Hyperostosis Syndrome/therapy , Disease Progression , Humans , Prognosis
6.
Food Chem ; 128(2): 364-70, 2011 Sep 15.
Article in English | MEDLINE | ID: mdl-25212143

ABSTRACT

The aim of this study was to optimise the electrically assisted extraction in order to obtain grape pomace extracts with high polyphenols content, which would be potentially interesting for applications as natural antioxidants. High voltage electrical discharges (HVED) were applied for intensification of the extraction. The effects of the energy input, the electrodes distance gap and the liquid-to-solid ratio were studied. Diffusion was then carried out in different mixtures of water and ethanol for one hour at 20, 30, 40 and 60°C. The most efficient extraction was (i) an HVED pre-treatment at 80kJ/kg with an electrodes distance of 5mm in a liquid-to-solid ratio of 5 followed by (ii) a diffusion with 30% ethanol in water at 60°C for 30min. The highest total polyphenols content reached 2.8±0.4gGAE/100gDM with a corresponding antioxidant activity of 66.8±3.1gTEAC/kgDM. The polyphenols extraction rate increased with temperature in accordance to an Arrhenius type of relationship: activation energy of 21.5±1.1kJ/mol for HVED treated systems against 0.5±0.2kJ/mol for untreated ones.

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