MD microcapsules containing all tested antioxidant compounds presented the same scavenging capacity than empty MD microcapsules (Table 1). Incorporation RG7420 manufacturer of apo-8′-carotenal to GA microcapsules promoted a 50%/μmol g increase in the scavenging capacity, and β-carotene contributed with less than 30%/μmol g (Table 2). The empty GA microcapsules presented a marked difference, 60%, between the ONOO− scavenging capacity in the presence
and absence of NaHCO3, but the empty MD microcapsules did not (Table 1). The GA microcapsules containing trolox were the most effective ONOO− scavengers, both in the presence and absence of NaHCO3 (Table 1). The incorporation of apo-8′-carotenal and β-carotene to GA microcapsules increased the capacity to scavenge ONOO−, without NaHCO3, in 132 and 43%/μmol g, respectively; meanwhile, when these carotenoids were incorporated to MD microcapsules, the increase was only 39%/μmol g for apo-8′-carotenal and 10%/μmol g for β-carotene.
Interestingly, when NaHCO3 was added to the reaction system, the incorporation of apo-8′-carotenal did not affect the scavenging capacity of GA microcapsules; however, in MD microcapsules, JQ1 solubility dmso the scavenging capacity raised 62%/μmol g. A similar effect was observed when apo-12′-carotenal was incorporated to MD microcapsules. The polymers used as wall materials for microencapsulation were in the past considered inert and their main functions were Flucloronide to protect and to control the liberation of the encapsulated compounds. However, recent studies have shown that some polymers used as wall materials, such as gum arabic, agar-agar, alginic acid, guar and xanthan gums, possess antioxidant capacity (Faria et al., 2010, Montenegro et al., 2007 and Trommer and Nerbert, 2005). For example, microencapsulated GA was able to delay photo-oxidation in skimmed
milk by efficiently quenching the riboflavin triplet state (Montenegro et al., 2007). The previous study carried out by Faria et al. (2010) also showed that the empty microcapsules of GA and MD were able to quench singlet oxygen. In the present study, the empty microcapsules also showed capacity to scavenge all the studied ROS and RNS in a concentration dependent manner. In general, when the capacity to scavenge ROS and RNS was compared, considering the microcapsule concentration in mg of biopolymer per ml of water, GA showed to be a more potent ROS and RNS scavenger than MD. GA is a complex and variable mixture of arabinogalactan oligosaccharides, polysaccharides and glycoproteins, resulting in a high molecular weight biopolymer (MW ≈ 350 kDa) (Renard, Lavenant-Gourgeon, Ralet, & Sanchez, 2006), whilst MD (MW ≈ 1 kDa) is a mixture of short polymers of d-glucose (3–20 units), in which the α-d-glucopyranosyl monomers are joined by (1 → 4) linkages to give linear chains with a certain degree of chain branching due to (1 → 6) bonding (Kennedy, Noy, Stead, & White, 1985).