Search results for "caroténoïdes"
showing 5 items of 5 documents
Problématiques de la nutrition en ophtalmologie – application à la dégénérescence maculaire liée à l’âge
2014
Nutrition in ophthalmology – clinical application to age-related macular degeneration «Let food be your medicine.» This contribution from Hippocrates is still timely addressed, especially in the field of ophthalmology. Observational epidemiology reports close associations between food habits and the risk or prevention of several ocular pathologies such as cataract or Age-related Macular Degeneration (AMD). Anti-oxidant vitamins, minerals and lipids are the nutrients that have been the most widely studied. Interventional epidemiology and experimental works partially corroborated these findings. Unexpectedly, the benefit of long chain omega 3 polyunsaturated fatty acids in the prevention of l…
Eco-extraction and encapsulation of carotenoid and anthocyanin pigments from tropical plants
2018
This thesis deals with extraction processes using assistance technologies or green solvents and encapsulation systems of natural pigments in order to exploit and apply them in the food, cosmetic and pharmaceutical industries. In this goal, microwave-assisted extraction (MAE), ultrasonic-assisted extraction (UAE) and Ionic liquids (IL) were evaluated for the extraction of carotenoids and anthocyanins from Vietnamese plants. The results obtained show that the MAE was always a rapid and helpful system for all types of extraction tested whereas ultrasounds were particularly efficient when pigments are present on the surface of plant tissues. However, UAE was also improving results compared to c…
Heterogeneity of host-parasite relationships : ecological and evolution significance
2005
Although parasites have been studied for a long time, the major knowledge concern parasite which have medical or veterinary interest. Whereas they are omnipresent in the nature, the role of parasite infections on natural populations is poorly understood. One of the aim of this work was to study the pathogenicity of two groups of parasites (ticks and Haemosporidae) among natural populations of blackbirds. The study revealed that both parasites are associated with body condition and immune response. However, the study of an urban blackbird population did not confirm the effect of Haemosporidae on the survey and on the population dynamic.The impact of spatial pattern on the relation between ho…
Utilisation of natural carotenoids from Momordica cochinchinensis (gac) as health compounds : extraction and bioactvity depending on the origin and o…
2014
The aril of Momordica cochinchinensis (gac), plant from the Cucurbitaceae family, is the richest source of lycopene and β-carotene, which are a strong antioxidant and a pro-vitamin A, respectively, interesting for health-complements. First, a process of soft extraction-fractionation was developed for extracting effectively the natural carotenoids from gac without loss of their original quality. Then, the lycopene and β-carotene extracted from gac were analyzed and characterized. At least 95% of the extracts were composed of the all-trans isomer. They were not degraded during the heat-treatment mimicking formulation processing. Their thermal stereo-mutation was evaluated. Lycopene is more an…