Effect of different drying procedures on the bioactive polysaccharide acemannan from Aloe vera (Aloe barbadensis Miller). (15th July 2017)

• Record Type: Journal Article
• Authors: Minjares-Fuentes, Rafael; Rodríguez-González, Víctor Manuel; González-Laredo, Rubén Francisco; Eim, Valeria; González-Centeno, María Reyes; Femenia, Antoni
• Is Part Of: Carbohydrate polymers. Volume 168(2017)
• Page Start: 327
• Page End: 336
• Publication Date: 2017-07-15
• Subjects: Aloe vera -- Acemannan -- Drying procedures -- Acetylation -- Functional properties; Polysaccharides -- Periodicals; Polysaccharides -- Periodicals; Polysaccharides -- Périodiques; Electronic journals; 547.78
• DOI: 10.1016/j.carbpol.2017.03.087
• Languages: English
• ISSNs: 0144-8617

Abstract

Highlights: The effects of different drying procedures on bioactive polymer acemannan were studied. All drying methods caused considerable degradation of the acemannan structure. Deacetylation of the acemannan polymer was confirmed by 1 H NMR analysis. Degradation of the acemannan structure led to a dramatic reduction of the functional properties. Modification of acemannan structure could also affect the beneficial properties of Aloe vera . Abstract: The main effects of different drying procedures: spray-, industrial freeze-, refractance window- and radiant zone-drying, on acemannan, the main bioactive polysaccharide from Aloe vera gel, were investigated. All the drying procedures caused a considerable decrease in the acemannan yield (∼40%). Degradation affected not only the backbone, as indicated by the important losses of (1 → 4)-linked mannose units, but also the side-chains formed by galactose. In addition, methylation analysis suggested the deacetylation of mannose units (>60%), which was confirmed by 1 H NMR analysis. Interestingly, all these changes were reflected in the functional properties which were severely affected. Thus, water retention capacity values from processed samples decreased ∼50%, and a reduction greater than 80% was determined in swelling and fat adsorption capacity values. Therefore, these important modifications should be taken into consideration, since not only the functionality but also the physiological effects attributed to many Aloe vera -based products could also be affected.