ABSTRACT
Inhibition of galectin-3-mediated interactions by modified citrus pectin (MCP) could affect several rate-limiting steps in cancer metastasis, but the ability of MCP to antagonize galectin-8 function remains unknown. We hypothesized that MCP could bind to galectin-8 in addition to galectin-3. In this study, a combination of gradual ethanol precipitation and DEAE-Sepharose Fast Flow chromatography was used to isolate several fractions from MCP. The ability of these fractions to antagonize galectin-8 function was studied as well as the primary structure and initial structure-function relationship of the major active component MCP-30-3. The results showed that MCP-30-3 (168 kDa) was composed of Gal (13.8%), GalA (63.1%), GlcA (13.0%), and Glc (10.1%). MCP-30-3 could specifically bind to galectin-8, with an MIC value of 0.04 mg mL-1. After MCP-30-3 was hydrolyzed by ß-galactosidase or pectinase, its binding activity was significantly reduced. These results provide new insights into the interaction between MCP structure and galectin function, as well as the potential utility in the development of functional foods.
Subject(s)
Citrus , Galectins , Pectins , Humans , Blood Proteins/chemistry , Blood Proteins/metabolism , Citrus/chemistry , Galectin 3/metabolism , Galectins/metabolism , Galectins/chemistry , Pectins/chemistry , Pectins/pharmacology , Polygalacturonase/chemistry , Polygalacturonase/metabolism , Protein BindingABSTRACT
Zanthoxylum bungeanum has a lengthy history of widespread use as a food ingredient in China. However, the composition of Zanthoxylum bungeanum polysaccharide remains ambiguous, and the antioxidant effect has received limited attention. This study aimed to extract water-soluble polysaccharide from the dried pericarp of Zanthoxylum bungeanum, referred to as WZBP, which was fractionated into a neutral component (WZBP-N) and three pectic components (WZBP-A-I, WZBP-A-II, WZBP-A-III). The findings indicated that WZBP-A-III is a pectic polysaccharide "smooth region" without many side chains. All components of WZBP exhibited a notable capacity for scavenging free radicals, with WZBP-A-III demonstrating the most potent antioxidation activity, and WZBP-A-III also observed to effectively extend the lifespan of Drosophila melanogaster and enhanced the activity of antioxidant enzymes. These results provide valuable insight and direction for future research on Zanthoxylum bungeanum polysaccharide as an antioxidant agent.
