Gut health benefits of kiwifruit pectins: Comparison with commercial functional polysaccharides

The role of kiwifruit pectin as a functional food ingredient capable of beneficial gut health effects in vitro was investigated. Six different pectins were obtained from the kiwifruit cultivar Actinidia deliciosa ‘Hayward’ (ZESPRI™ GREEN) by selective re-solubilisation of the fruit fibre with different chemical treatments. The potential gut health benefit of kiwifruit pectin was tested with respect to its influence on bacterial adhesion to intestinal epithelial cells (Caco-2) in vitro. The most effective kiwifruit pectin (monoK pectin), obtained by re-solubilisation with monopotassium phosphate, was compared with three commercial functional polysaccharides - citrus pectin, guar gum and inulin. The monoK pectin was superior to inulin, a standard prebiotic in enhancing the adhesion of Lactobacillus rhamnosus and decreasing the adhesion of Salmonella typhimurium to Caco-2 cells. The adhesion of Bifidobacterium bifidum was significantly enhanced only by inulin and citrus pectin, while guar gum had no effect on adhesion of any of these bacteria.