1. Ozonolysis Treatment Colorimetric assays Intrinsec Viscosity
EFFECT OF OZONE TREATMENT ON DEGRADATION OF
POLYSACCHARIDES FROM TUNISIAN ARTHROCNEMUM INDICUM:
PHYSICO-CHEMICAL PROPRIETIES AND ANTIOXIDANT ACTIVITIY
Zeineb MZOUGHIa, Mariem ITAIMI DAMMAKa, Sarra Ben Hmidab, Sawssen Amamouc, Didier Le Cerfd, Hatem MAJDOUBa
a) Laboratoire des Interfaces et des Matériaux Avancés (LIMA), Faculté des Sciences de Monastir, Université de Monastir, Bd. de l’environnement, 5019 Monastir, Tunisia
b) Laboratoire de Génie Textile (LGTex), Institut Supérieur des Etudes Technologiques de ksar Hellal, Université de Monastir, 5070 Monastir, Tunisia.,
c) Laboratoire de Recherche : Bio-ressources, Biologie Intégrative & Valorisation (LR14ES06), Institut Supérieur de Biotechnologie de Monastir, Université de Monastir, Avenue Tahar Hadded, BP 74, 5000 Monastir, Tunisia
d) Normandie Université, Laboratoire Polymères Biopolymères Surfaces (PBS), UMR 6270 & FR 3038 CNRS, Université de Rouen, Mont Saint Aignan, France
Introduction
Polysaccharides degradation was achieved by enzymatic, chemical, physical and thermal prosseses1. However, these techniques have various disadvantages such as obtaining lower yields and altering chemical structure of the depolymerized polysaccharides. Thus, the development of an emerging technology for depolymerization and bleaching of high molecular weight carbohydrates, without modification of its chemical structure, is of great interest.
In this work, we are interested in the ozonolytic degradation of polysaccharides from Tunisian Arthrocnemum indicum leaves and the study of the influence of their molecular weight on the antioxidant activity.
Structural characterization
Optimization of polysaccharides
extraction
FT-IR
Central Composite Design (CCD)
ARTHROCNEMUM INDICUM
Extraction temperature: 80°C
Extraction time: 288 min
Ozonolysis
Treatment
Extraction yield: 7.91%
Uronic acid content: 57.53%
Solvent to material
ratio:38 mL/g
Antioxidant capacity:
IC50= mg/mL
Chemical structure
confirmed
Various reaction times (0,15,30,45 and 60 min)
Colorimetric assays
Intrinsec Viscosity
Increase of galacturonic acid level with the duration of Ozone depolymerization
Antioxidant Activity
CIELab coordinates
Remarkable decrease in total sugars
Strongest inhibition potential in all tests
Conclusion
Our study focused on the effect of molecular weight on the antioxidant capacity of polysaccharide extracted from Arthrocnemum indicum leaves. We resorted to the ozonolytic depolymerization in aqueous solution. The viscosimetric study showed that the degraded polysaccharides fraction had a larger reduction in function of the treatment duration. FTIR analysis suggest that no major functional group transformations happened during depolymerization. The surface color analysis indicated that degraded polysaccharides has a slightly yellow appearance which achieved the transparency at the end of degradation time. Furthermore, degraded polysaccharides showed significant antioxidant activities which was mainly due to their low molecular weight and the high galacturonic acid content.
1 Chaouch, M.A., Hafsa, J., Rihouey, C., Le Cerf, D., Majdoub, H., 2015a. Depolymerization of polysaccharides from Opuntia ficus indica: Antioxidant and antiglycated activities. International journal of biological macromolecules 79,
19th Tunisia Chemistry Conference - TCC 2016
18-22 December 2016