1. Effect of Clarification Techniques and Rat Intestinal Extract Incubation on Phenolic Composition and Antioxidant Activity of Black Currant Juice
- Author
-
Anne-Katrine Regel Landbo, Anders Falk Vikbjerg, Anne S. Meyer, and Manuel Pinelo
- Subjects
Male ,Antioxidant ,Food Handling ,medicine.medical_treatment ,Flavonoid ,Centrifugation ,Antioxidants ,Anthocyanins ,Beverages ,chemistry.chemical_compound ,Ribes ,Phenols ,Intestinal mucosa ,medicine ,Animals ,Humans ,Food science ,Lipoprotein oxidation ,Gallic acid ,Rats, Wistar ,chemistry.chemical_classification ,beta-Glucosidase ,General Chemistry ,Rats ,Intestines ,Lipoproteins, LDL ,Enterocytes ,chemistry ,Biochemistry ,Polyphenol ,Fruit ,Anthocyanin ,General Agricultural and Biological Sciences - Abstract
This study examined the phenolic composition and the antioxidant potencies of black currant juices that had been experimentally clarified with acidic proteases and pectinases to retain the phenolics and which had been subjected to rat intestinal mucosa extract incubation to mimic gut cell mediated biotransformation of phenolics. When compared at equimolar levels of 2.5 microM gallic acid equivalents, the black currant juice samples prolonged the induction time of human low-density lipoprotein oxidation in vitro by 2.6-3.6 times, and the order of antioxidant potency of differently clarified black currant juices was centrifuged juicegelatin silica sol clarified juiceenzymatically clarified juice approximately raw juice. No immediate relationship between the, almost similar, phenolic profiles of the juice samples and their relative antioxidant activities could be established. Incubation of juices with a rat small intestine cell extract for 19 h promoted significant decreases in the contents of the anthocyanin 3-O-beta-glucosides (cyanidin 3-O-beta-glucoside and delphinidin 3-O-beta-glucoside), but did not affect the anthocyanin 3-O-beta-rutinosides (cyanidin 3-O-beta-rutinoside and delphinidin 3-O-beta-rutinoside) of the black currant juice. Black currant juice samples subjected to such intestinal cell extract incubation had approximately 30% decreased antioxidant capacity. Incubation of juices with the rat small intestine cell extracts at neutral pH appeared to decrease the levels of delphinidin glucosides more than the levels of cyanidin glucosides. The results provide an explanation for the predominant detection of anthocyanin rutinosides, and not anthocyanin glucosides, in plasma and urine in in vivo studies and provide important clues to better understand the complex mechanisms affecting dietary phenols in the gut.
- Published
- 2006