Analytical Chemistry in Industrial Food Research

Because of the complexity of food matrices, analytical chemistry has a key role to play in the elucidation of food composition, food stability and its behaviour during processing. In this paper, the application of various analytical techniques (e.g., near IR spectroscopy, electronic nose technology, nuclear magnetic resonance and mass spectrometry) are discussed

Selenium absorption and retention from a selenite- or selenate-fortified milk-based formula in men measured by a stable-isotope technique

The present study was designed to determine the apparent absorption and retention of the inorganic Se compounds SeO32- and SeO42-, which are commonly used for Se fortification of clinical nutrition products and infant formulas. Ten healthy men were fed a milk-based formula labelled with 40 μg Se as 74SeO32- or 76SeO42- on two consecutive days using a randomised crossover design. Se stable-isotope analysis of 9 d complete collections of urine and faeces was used to calculate apparent Se absorption and retention. Se retention from 74SeO32- (41·0 (SD 8·4) %) AND FROM 76SEO42- (46·0 (sd 7·9) %) was not significantly different (P>0·05). However, Se absorption was significantly higher from SeO42- than from SeO32- (91·3 (sd 1·4) % v. 50·2 (sd 7·8) %, P<0·05). Urinary excretion of the administered dose was 9·2 (sd 1·8) % for 74SeO32- and 45y3 (sd 8·2) % for 76SeO42- (P<0·05). Urinary Se excretion kinetics differed significantly for the two Se compounds; 90 % of the total urinary Se was excreted after 121 h for 74SeO32- and after 40 h for 76SeO42- (P<0·05). These results suggest that although Se absorption and urinary excretion differ for SeO32- and SeO42-, both Se compounds are equally well retained when administered at a relatively low dose (40 μg Se). The nutritional impact of Se fortification of foods would thus be expected to be similar when SeO42- or SeO32- are use

Influence of amino acids on the formation of mutagenic/carcinogenic heterocydic amines in a model system

Mixtures of creatinine, glucose and various single amino acids were heated at 180°C for 10 min in an aqueous model system. The heated mixtures all showed mutagenic activity, ranging from 80 to 2400 TA98 revertant colonies/μmol creatinine with metabolic activation. Testing of HPLC fractions for mutagenic activity showed each mixture to contain several mutagenic components, some of which corresponded to known heterocyclic amines and others to unknown compounds. The presence of 2-amino-3-methyl-imidazo[4,5-f]quinoxaline, 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline and 2-amino-3,7,8-trimethylimidazo[4,5-f]quinoxaline in most of the samples was established using HPLC with photodiode array detection and liquid chromatography/mass spectrometry with electrospray interface and single ion monitoring. In addition, 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, 3-amino-1,4-di-methyl-5H-pyrido[4,3-b]indole and 3-amino-1-methyl-5H-pyrido[4,3-b]indole and the co-mutagenic compounds 9H-pyrido[3,4-bindole and 1-methyl-9H-pyrido[3,4-b]indole were detected in some sample

Study on the Decomposition of the Amadori Compound N-( l-Deoxy-D-fructos-l-yl)-glycine in Model Systems : Quantification by Fast Atom Bombardment Tandem Mass Spectrometry

A new method for the quantification of N-(ldeoxy-D-huctas-l-yl)-glycine (DFG) was developed based on isotope dilution fast atom bombardment tandem mass spectrometry using &apos;3C-laheUed DFG as an internal standard. This method, which requires neither derivatization nor clean-up of the samples, was used to study the degradation of DFG under different conditions (time and pH). It was found that the decomposition of DFG at 90°C was favoured at pH 7 compared to pH 6. The higher stability of DFG at pH 6 was due to 1,2-enolization leading to the relatively stable 3deoxglucoson

A whole-grain cereal-rich diet increases plasma betaine, and tends to decrease total and LDL-cholesterol compared with a refined-grain diet in healthy subjects

Epidemiological studies have repeatedly found that whole-grain (WG) cereal foods reduce the risk of several lifestyle-related diseases, though consistent clinical outcomes and mechanisms are elusive. To compare the effects of a WG-rich diet with a matched refined-grain (RG) diet on plasma biomarkers and bowel health parameters, seventeen healthy subjects (eleven females and six males) completed an exploratory cross-over study with a 2-week intervention diet based on either WG- or RG-based foods, separated by a washout of at least 5 weeks. Both diets were the same except for the use of WG (150g/d) or RG foods. Subjects undertook a 4h postprandial challenge on day 8 of each intervention diet. After 2 weeks, the WG diet tended to decrease plasma total and LDL-cholesterol (both P=0·09), but did not change plasma HDL-cholesterol, fasting glucose, C-reactive protein or homocysteine compared with the RG diet. Plasma betaine and alkylresorcinol concentrations were elevated after 1 week of the WG diet (P=0·01 and P<0·0001, respectively). Clostridium leptum populations in faeces were increased after the WG diet, along with a trend for decreased faecal water pH (P=0·096) and increased stool frequency (P<0·0001) compared with the RG diet. A short controlled intervention trial with a variety of commercially available WG-based products tended to improve biomarkers of CVD compared with a RG diet. Changes in faecal microbiota related to increased fibre fermentation and increased plasma betaine concentrations point to both fibre and phytochemical components of WG being important in mediating any potential health effect

Probiotic modulation of symbiotic gut microbial–host metabolic interactions in a humanized microbiome mouse model

The transgenomic metabolic effects of exposure to either Lactobacillus paracasei or Lactobacillus rhamnosus probiotics have been measured and mapped in humanized extended genome mice (germ-free mice colonized with human baby flora). Statistical analysis of the compartmental fluctuations in diverse metabolic compartments, including biofluids, tissue and cecal short-chain fatty acids (SCFAs) in relation to microbial population modulation generated a novel top-down systems biology view of the host response to probiotic intervention. Probiotic exposure exerted microbiome modification and resulted in altered hepatic lipid metabolism coupled with lowered plasma lipoprotein levels and apparent stimulated glycolysis. Probiotic treatments also altered a diverse range of pathways outcomes, including amino-acid metabolism, methylamines and SCFAs. The novel application of hierarchical-principal component analysis allowed visualization of multicompartmental transgenomic metabolic interactions that could also be resolved at the compartment and pathway level. These integrated system investigations demonstrate the potential of metabolic profiling as a top-down systems biology driver for investigating the mechanistic basis of probiotic action and the therapeutic surveillance of the gut microbial activity related to dietary supplementation of probiotics

A top-down systems biology view of microbiome-mammalian metabolic interactions in a mouse model

Symbiotic gut microorganisms (microbiome) interact closely with the mammalian host's metabolism and are important determinants of human health. Here, we decipher the complex metabolic effects of microbial manipulation, by comparing germfree mice colonized by a human baby flora (HBF) or a normal flora to conventional mice. We perform parallel microbiological profiling, metabolic profiling by 1H nuclear magnetic resonance of liver, plasma, urine and ileal flushes, and targeted profiling of bile acids by ultra performance liquid chromatography–mass spectrometry and short-chain fatty acids in cecum by GC-FID. Top-down multivariate analysis of metabolic profiles reveals a significant association of specific metabotypes with the resident microbiome. We derive a transgenomic graph model showing that HBF flora has a remarkably simple microbiome/metabolome correlation network, impacting directly on the host's ability to metabolize lipids: HBF mice present higher ileal concentrations of tauro-conjugated bile acids, reduced plasma levels of lipoproteins but higher hepatic triglyceride content associated with depletion of glutathione. These data indicate that the microbiome modulates absorption, storage and the energy harvest from the diet at the systems level

Survival of the Fittest: Positive Selection of CD4+ T Cells Expressing a Membrane-Bound Fusion Inhibitor Following HIV-1 Infection

Although a variety of genetic strategies have been developed to inhibit HIV replication, few direct comparisons of the efficacy of these inhibitors have been carried out. Moreover, most studies have not examined whether genetic inhibitors are able to induce a survival advantage that results in an expansion of genetically-modified cells following HIV infection. We evaluated the efficacy of three leading genetic strategies to inhibit HIV replication: 1) an HIV-1 tat/rev-specific small hairpin (sh) RNA; 2) an RNA antisense gene specific for the HIV-1 envelope; and 3) a viral entry inhibitor, maC46. In stably transduced cell lines selected such that >95% of cells expressed the genetic inhibitor, the RNA antisense envelope and viral entry inhibitor maC46 provided the strongest inhibition of HIV-1 replication. However, when mixed populations of transduced and untransduced cells were challenged with HIV-1, the maC46 fusion inhibitor resulted in highly efficient positive selection of transduced cells, an effect that was evident even in mixed populations containing as few as 1% maC46-expressing cells. The selective advantage of the maC46 fusion inhibitor was also observed in HIV-1-infected cultures of primary T lymphocytes as well as in HIV-1-infected humanized mice. These results demonstrate robust inhibition of HIV replication with the fusion inhibitor maC46 and the antisense Env inhibitor, and importantly, a survival advantage of cells expressing the maC46 fusion inhibitor both in vitro and in vivo. Evaluation of the ability of genetic inhibitors of HIV-1 replication to confer a survival advantage on genetically-modified cells provides unique information not provided by standard techniques that may be important in the in vivo efficacy of these genes

Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good