Digestibility of resistant starch containing preparations using two in vitro models

BACKGROUND: Resistant starch (RS) is known for potential health benefits in the human colon. To investigate these positive effects it is important to be able to predict the amount, and the structure of starch reaching the large intestine. AIM OF THE STUDY: The aim of this study was to compare two different in vitro models simulating the digestibility of two RS containing preparations. METHODS: The substrates, high amylose maize (HAM) containing RS type 2, and retrograded long chain tapioca maltodextrins (RTmd) containing RS type 3 were in vitro digested using a batch and a dynamic model, respectively. Both preparations were characterized before and after digestion by using X-Ray and DSC, and by measuring their total starch, RS and protein contents. RESULTS: Using both digestion models, 60-61 g/100 g of RTmd turned out to be indigestible, which is very well in accordance with 59 g/100 g found in vivo after feeding RTmd to ileostomy patients. In contrast, dynamic and batch in vitro digestion experiments using HAM as a substrate led to 58 g/100 g and 66 g/100 g RS recovery. The degradability of HAM is more affected by differences in experimental parameters compared to RTmd. The main variations between the two in vitro digestion methods are the enzyme preparations used, incubation times and mechanical stress exerted on the substrate. However, for both preparations dynamically digested fractions led to lower amounts of analytically RS and a lower crystallinity. CONCLUSIONS: The two in vitro digestion methods used attacked the starch molecules differently, which influenced starch digestibility of HAM but not of RTmd

Prebiotic effects of a wheat germ preparation in human healthy subjects

A double-blind placebo-controlled study was performed to investigate the behaviour of different intestinal bacterial groups in 32 healthy subjects during treatment with the prebiotic wheat germ preparation Viogerm\uaePB1. Microbiological methods and fluorescent in situ hybridization technique were used to identify the following bacterial groups: coliforms, clostridia, bacteroides, lactobacilli and bifidobacteria. After 20 days of supplementation of the product, the coliform population and pH decreased significantly. The number of lactobacilli and bifidobacteria increased significantly only in subjects with low basal levels. No significant changes were observed for the other bacterial groups and total bacteria did not increase. Treatment with placebo did not induce any variation. These results showed that the product Viogerm\uaePB1 possesses a prebiotic effect and has a potential to improve host's health

Prebiotic effects of a wheat germ preparation in human healthy subjects

A double-blind placebo-controlled study was performed to investigate the behaviour of different intestinal bacterial groups in 32 healthy subjects during treatment with the prebiotic wheat germ preparation ViogermsPB1. Microbiological methods and fluorescent in situ hybridization technique were used to identify the following bacterial groups: coliforms, clostridia, bacteroides, lactobacilli and bifidobacteria. After 20 days of supplementation of the product, the coliform population and pH decreased significantly. The number of lactobacilli and bifidobacteria increased significantly only in subjects with low basal levels. No significant changes were observed for the other bacterial groups and total bacteria did not increase. Treatment with placebo did not induce any variation. These results showed that the product ViogermsPB1 possesses a prebiotic effect and has a potential to improve host\u2019s healt

CLARA conceptual design report

This report describes the conceptual design of a proposed free electron laser test facility called CLARA that will be a major upgrade to the existing VELA accelerator test facility at Daresbury Laboratory in the UK. CLARA will be able to test a number of new free electron laser schemes that have been proposed but require a proof of principle experiment to confirm that they perform as predicted. The primary focus of CLARA will be on ultra short photon pulse generation which will take free electron lasers into a whole new regime, enabling a new area of photon science to emerge