Short-chain fatty acid content and pH in caecum of rats fed various sources of starch

Caecal pH and contents of short-chain fatty acids (SCFA) were registered in rats fed three potential sources of resistant starch (RS); raw pea starch, raw potato starch, and an RS-enriched preparation obtained from wheat starch by autoclaving and enzymatic incubation. Small intestinal digestibility and delivery of RS to the hind-gut in the case of raw starches were determined by analysis of faecal starch in animals treated with antibiotics to prevent hind-gut fermentation. RS content in the RS-enriched preparation was determined as total starch remaining in an enzymatic gravimetric dietary fibre residue. The fermentability of RS was estimated from the faecal recovery of starch in normal animals with intact hind-gut microflora. Approximately 35 g per 100 g and 32 g per 100 g were RS in the case of raw potato starch and the RS-enriched preparation, respectively, versus only 1 g per 100 g in the case of raw pea starch. The caecal pH decreased with all test diets, being most significant with raw potato starch. SCFA production and faecal bulking were negligible with raw pea starch, whereas both raw potato starch and the RS-enriched preparation significantly increased these parameters. The fermentability of RS in raw potato starch and the RS-enriched preparation was similar, or about 60–70%. If calculated on basis of fermented amount, RS in raw potato starch was more potent in generating SCFA (49 μmol g^?1) than in the RS-enriched preparation (19 μmol g^?1). RS in raw potato starch also displayed the highest faecal bulking capacity. In fact, the faecal dry weight increased more than expected merely from delivery of RS. The relative proportion in caecal contents of acetic-, propionic- and butyric acid was 70, 17 and 8%, respectively, with no significant differences between the three sources of RS.     

Metabolomic approach to identifying bioactive compounds in berries: advances toward fruit nutritional enhancement

Plant polyphenolics continue to be the focus of attention with regard to their putative impact on human health. An increasing and ageing human population means that the focus on nutrition and nutritional enhancement or optimisation of our foodstuffs is paramount. Using the raspberry as a model, we have shown how modern metabolic profiling approaches can be used to identify the changes in the level of beneficial polyphenolics in fruit breeding segregating populations and how the level of these components is determined by genetic and/or environmental control. Interestingly, the vitamin C content appeared to be significantly influenced by environment (growth conditions) whilst the content of the polyphenols such as cyanidin, pelargonidin and quercetin glycosides appeared much more tightly regulated, suggesting a rigorous genetic control. Preliminary metabolic profiling showed that the fruit polyphenolic profiles divided into two gross groups segregating on the basis of relative levels of cyanidin-3-sophoroside and cyanidin-3-rutinoside, compounds implicated as conferring human health benefits.     

Antioxidants in Fish Oil Production for Improved Quality

There is an increasing demand for fish oil containing omega-3. By-products (e.g., heads, tails, belly flaps, backbones, and viscera) from fish fillet production are currently utilized for production of fish oil and fish meal for feed but can be a valuable source of omega-3 for human consumption. However, the quality of some oil is not good enough for human consumption due to oxidation during processing. The aim of this work was to decrease oxidation during oil production by adding antioxidants to herring by-products early in the production process. Of several antioxidants the most potent were selected by a fast screening test. Butylated hydroxytoluene, propyl gallate and citric acid were further evaluated on a labaroatory scale and pilot plant production of herring oil. The selected antioxidants resulted in lower total oxidation during processing [up to 71% reduction in TOTOX (2 times the peroxide value plus the anisidine value)]. In addition, higher oil stability was achieved by adding antioxidants during processing (improved stability up to 400%).     

Optimization of Multicomponent Cobalt Spinel Catalyst for N2O Abatement from Nitric Acid Plant Tail Gases: Laboratory and Pilot Plant Studies

The influence of Zn and K promoters on N₂O decomposition over Co₃O₄ was investigated by work function measurement and temperature-programmed surface reaction. The beneficial effect of the promoters resulting in spectacular decrease in the temperature of 50% conversion by 200 °C was found to be essentially of electronic origin. The strong correlation between the catalyst work function and deN₂O activity allowed for the optimization of the doping level of both additives. The pilot plant tests in real nitric acid tail gases revealed that the optimized double promoted (Zn, K) cobalt spinel catalyst maintained its remarkable activity in N₂O decomposition (conversion >95% at the target temperature of 350 °C) for more than 60 h.     

Preliminary evaluation of fumonisins by the Nordic countries and occurrence of fumonisins (FB1 and FB2) in corn-based foods on the Danish market

Experts from the Nordic countries (Denmark, Norway, Sweden, Finland and Iceland) have carried out an evaluation of fumonisins. The working group members concluded that, at that time point, it was not possible to carry out a complete risk assessment. However, it was recommended that the human daily' intake of fumonisins should be less than 1 microg/kg bw/day. Subsequently, the presence of the Fusarium mycotoxins fumonisin B1 and B2 (FB1 and FB2) in corn-based food on the Danish retail market has been determined. A total of 70 samples were analysed and 37% contained FB1 and 21% contained FB2. No fumonisins were found in sweet corn (canned or frozen), corn-on-the-cob, corn starch or gruel powder for babies. FB1 was found in about half of the corn flakes, corn snack and popcorn (not popped) samples, whereas FB2 was seen to a lesser extent. Both FB1 and FB2 were found in 75% or more of the corn flour, tacos and polenta samples. In general, the content of FB1 was in the range of 1-1000 micro/kg and the content of FB2 was in the range of 4-250 microg/kg. Corn-based foods are consumed in rather low amounts and irregularly among the Danish population and therefore it is not meaningful to calculate an average daily funonisin intake. An estimate for an 'eater' shows that the intake of fumonisins will not exceed 0.4 microg/kg bw/day.     

11C]beta-CIT-FE, a radioligand for quantitation of the dopamine transporter in the living brain using positron emission tomography

Patients with gastrointestinal hemorrhage are frequently admitted to critical care units, in large part to be observed for signs of hemodynamic instability. All patients admitted with gastrointestinal bleeding to our medical intensive care unit over a 1-year period (n=108) were retrospectively reviewed to determine the incidence of hemodynamic instability. In an elderly patient population with predominantly nonvariceal bleeding, only 13% of those admitted had documented hypotension that led to an intervention. Only 7% had clinically significant hypotension after the first 5 hours of admission. Admission clinical criteria were analyzed by multivariate analysis but could not reliably predict patients at increased risk for hemodynamic instability. However, patients without significant comorbid illness who have been endoscopically shown to have a low-risk lesion can be considered for early transfer to a regular bed after a short period of close observation. This could lead to better resource utilization and cost savings without jeopardizing patient care.     

Some physical and nutritional characteristics of genetically modified potatoes varying in amylose/amylopectin ratios

Transgenically modified potatoes with a large spread in amylose/amylopectin ratios were analysed both as tubers and in the form of isolated starch. Different microscopic techniques were used to study starch granules and tuber tissue. Starch gelatinisation properties and recrystallisation of amylopectin and amylose were studied by differential scanning calorimetry. Starch bioavailability and resistant starch (RS) were evaluated using enzymatic in vitro procedures. Glycaemic indices (GI) were predicted from low molecular weight carbohydrates (LMWC) contents and the in vitro hydrolysis rate of the starch moiety. For many of the examined parameters, differences of varying magnitude were found between the potato lines, especially for high amylose lines. High amylose starch granules had irregular shapes and showed only a limited swelling. Moreover, contents of RS and recrystallised amylose were elevated. GI’s for the starch moiety were reduced, though elevated contents of LMWC caused a high over-all predicted GI.     

PET-characterization of [carbonyl-11C]WAY-100635 binding to 5-HT1A receptors in the primate brain

A method for the accurate determination of 13C enrichments in nonprotonated carbon atoms of organic compounds that makes use of unresolved 13C satellites of proton(s) bonded to the vicinal carbon atom was developed. Using glutamate as a model molecule, this 1H nuclear magnetic resonance (NMR) inverse spin-echo difference spectroscopy method was calibrated for inversion efficiency and relaxation effects which were then shown to cause only a minor loss of the measured 13C satellite amplitude (2% for glutamate C-1 and 7% for glutamate C-5). The determination of 13C enrichments in nonprotonated glutamate carbon atoms by this method was shown to be more precise than 13C NMR. As a first application, a [5-13C]glucose labeling experiment with Corynebacterium glutamicum ASK1 was performed. The labeling patterns of glutamate and arginine extracted from cellular protein were determined using the newly developed method and standard 1H NMR with and without broadband 13C decoupling. Determination of the 13C enrichment in C-5 of glutamate and arginine, respectively, by the two methods showed good agreement. From the deduced labeling pattern of 2-oxoglutarate, an in vivo carbon flux distribution within the central metabolism of C. glutamicum ASK1 was calculated. Thus, the relative flux toward oxaloacetate via the tricarboxylic acid cycle enzyme malate dehydrogenase was determined as 45%, whereas that via anaplerotic C3 carboxylation was determined as 55%.