Biotransformation of caffeoyl quinic acids from green coffee extracts by Lactobacillus johnsonii NCC 533

Acknowledgements The authors are grateful to Nicole Page-Zoerkler and Olivier Mauroux for their technical assistant. We thank David Pridmore and Kimo Makkinen for critical reading of this manuscript.Peer reviewedPublisher PD

Cereal bran protects vitamin A from degradation during simmering and storage

Food supplementation with vitamin A is an efficient strategy to combat vitamin A deficiency. The stability of vitamin A during cooking and storage is, however, low. We here show that cereal bran protects retinyl palmitate (RP) during simmering and storage. Native wheat bran stabilized RP the most during simmering. About 75% RP was recovered after 120 min of cooking, while all RP was lost after 80 min in the absence of bran. Heat-treated rice bran protected RP the best during forced storage, with a 35% recovery after 8 weeks. RP was degraded entirely in the absence of bran in less than one week. Results suggested that the physical entrapment of oil within the large wheat bran particles protects RP from the action of water and pro-oxidants during simmering. During storage, the high amount and diversity of lipid components present in rice bran are presumably responsible for its protective effect.status: publishe

Hydrolysis of Chicoric and Caftaric Acids with Esterases and Lactobacillus johnsonii in Vitro and in a Gastrointestinal Model

Chicoric acid (ChA) and caftaric acid (CafA) were identified as bioactive components of chicory and have been ascribed a number of health benefits. This study investigated the hydrolysis of ChA and CafA with enzymes and a probiotic bacterium Lactobacillus johnsonii (La1). Esterase from Aspergillus japonicus (24 U/mg) hydrolyzed 100% of ChA (5 mM) and CafA (5 mM) after 3 h, at pH 7.0 and 37 °C. Under the same reaction conditions, 100% hydrolysis of ChA and CafA was achieved with a spray-dried preparation of La1. The addition of La1 (100 mg/mL, 3.3 E9 cfu/g) to CafA solution in a gastrointestinal model (GI model) resulted in 65% hydrolysis of CafA. This model simulates the physicochemical conditions of the human gastrointestinal tract. No hydrolysis of CafA was observed after passage through the GI model in the absence of La1. The results of this study support the hypothesis that ChA and CafA are degraded by gut microflora before absorption and metabolization