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1.
Neurochemical Research - Prebiotic oligosaccharides are demonstrated to confer a wide spectrum of physiological benefits during pregnancy. In view of this, focused attempts are being directed...  相似文献   
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Plackett–Burman design was used to efficiently select important media components influencing lactic acid production in a two step screening procedure. A total of 36 screening experiments were conducted for studying the effect of various media components such as carbon and nitrogen (simple and complex) sources, minerals/buffering agents and a specific inducer for the production of lactic acid by Lactobacillus plantarum NCIM 2084. The eleven ingredients chosen after the first screening experiments were further screened by a Plackett-Burman design consisting of 12 experiments. Liquefied starch, wheat bran extract, ammonium nitrate, manganese sulphate and sodium acetate were chosen as promising ingredients for further optimisation studies. The highest yield of 41.9?g/l of lactic acid was obtained at the end of 24 hours of fermentation which corresponded to 90% conversion, on the basis of sugar supplied.  相似文献   
3.
Vitamin B12 was produced by probiotic Lactobacillus plantarum in submerged fermentation (96 h) with successive anaerobic and aerobic phases of 48 h each to give 13 ng vitamin B12/g dry biomass. Sodium cyanide-mediated cell lysis, followed by benzyl alcohol/chloroform/water extraction, improved the release of intracellular vitamin B12 for analysis. The presence of the K+ adduct of cyanocobalamin (m/z of 1394) was established using electron spray ionization–mass spectra; growth of a mutant of Escherichia coli in the presence of cyanocobalamin ascertained its bioavailability.  相似文献   
4.
Isoamyl butyrate, an important fruity flavor ester, was synthesized using Rhizomucor miehei lipase immobilized on a weak anion exchange resin (Lipozyme IM-20) by the esterification of isoamyl alcohol and butyric acid. The effects of various reaction parameters such as substrate and enzyme concentrations, substrate molar ratio, temperature and incubation time have been investigated. Yields above 90% were obtained with substrate concentrations as high as 2.0 M. No evidence of enzyme inhibition by butyric acid was present up to 1.0 M concentration. Acid inhibition and, to a small extent, alcohol inhibition were evident above 1.0 M substrate concentration. Conversions reached a saturation value by the end of 24–48 h of incubation due to the accumulation of the water of reaction. The equilibrium was successfully pushed forward towards esterification by removing the accumulated water using a molecular sieve.Journal of Industrial Microbiology & Biotechnology (2000) 25, 147–154. Received 09 February 2000/ Accepted in revised form 24 June 2000  相似文献   
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The effect of a prebiotic (fructooligosaccharides) or a synbiotic components (prebiotic and probiotic) on the viability, proteolysis and antioxidant properties of probiotic and synbiotic yogurt during 28?days of storage at 4?°C has been investigated. Yogurt starters in conjunction with either probiotic bacteria Lactobacillus plantarum CFR 2194, Lactobacillus fermentum CFR 2192 and/or fructooligosaccharides (FOS) were used for yogurt preparation. Titratable acidity and pH of all yogurt samples followed a similar pattern of increase or decrease during storage. Proteolysis in synbiotic yogurts was found to be significantly (P?<?0.05) higher in comparison with that of control. The addition of prebiotics had no effect (P?=?0.17888) on the viability of yogurt starters during cold storage. No observable changes in the viability of probiotic cultures in probiotic groups. However, supplementation of FOS affected the growth significantly (P?<?0.05) in promoting the growth of L. plantarum and L. fermentum. Antioxidant activities, the index of nutritional value of yogurt, were monitored. Results showed that the DPPH-radical-scavenging activity (85?%) in synbiotic yogurt containing L. plantarum and FOS was significantly higher (P?<?0.05) in comparison with that of control yogurt (72?%). Total phenolics and the ferric reducing power were highest in synbiotic yogurts in comparison with that of other test samples during the entire period of storage. Addition of selected probiotics with FOS thus resulted in an improved functionality of yogurt.  相似文献   
7.
In this study, an attempt has been made to maximize the lipid production using response surface methodology (RMS). Levels of nitrogen, carbon, and inoculum were chosen as factors. The results indicated that inoculum level was very important in lipid production, followed by carbon and nitrogen levels. At higher levels of inoculum, the strain was found to be more tolerant to higher concentrations of sugar, and significantly increased lipid production was noticed. Through the fitted models of second order, as per RSM, carbon at 10.24%, nitrogen at 0.37 g/L, and inoculum at the 20% level resulted in maximum biosynthesis of lipids.  相似文献   
8.
The heartwood of Pterocarpus santalinus contains two major red pigments, santalin-A and santalin-B which are partial methyl ethers of the same polyphenol (santalin). For locating the position of the methoxyl groups, alkali fission and permanganate oxidation of the mixed ethyl methyl ethers are the most convenient. By this method santalin-A has been shown to be 9,1O,12- tri-O-methylsantalin and santalin-B, 9,10,12,4′-tetra-O-methylsantalin.  相似文献   
9.
Lactic cultures were screened for their ability to accumulate γ-aminobutyric acid (GABA) in the culture medium. Lactobacillus bulgaricus CFR 2028 produced the highest yields of GABA (22.7 mM) from the substrate monosodium glutamate (MSG). Instrumental characterization by high-performance liquid chromatography and structural characterization by mass spectrometry confirmed GABA production by L. bulgaricus CFR 2028. The differential production of GABA in complex and minimal media indicated that minimal medium (modified tryptone, yeast extract and glucose; TYG) supported the highest production of GABA (37 mM), thereby signifying that the acidic pH alone could have a significant bearing on the yield of GABA. This observation opens up avenues for the optimization of the medium components for yield maximization. The biotransformation kinetics of MSG was examined in batch experiments by varying initial MSG concentration (1–5 %). The Monod model was fitted to determine the kinetic parameters under the MSG uninhibited domain, and the MSG inhibited domain was represented well by Briggs–Haldane model.  相似文献   
10.
Methamphetamine (METH) abuse in conjunction with human immunodeficiency virus (HIV) exacerbates neuropathogenesis and accelerates neurocognitive impairments in the central nervous system (CNS), collectively termed HIV Associated Neurocognitive Disorders (HAND). Since both HIV and METH have been implicated in altering the synaptic architecture, this study focused on investigating alterations in synaptic proteins. Employing a quantitative proteomics approach on synaptosomes isolated from the caudate nucleus from two groups of rhesus monkeys chronically infected with simian immunodeficiency virus (SIV) differing by one regimen, METH treatment, we identified the neuron specific Na(+)/K(+)-ATPase alpha 1 isoform 3 (ATP1A3) to be up regulated after METH treatment, and validated its up regulation by METH in vitro. Further studies on signaling mechanisms revealed that the activation of ATP1A3 involves the extracellular regulated kinase (ERK) pathway. Given its function in maintaining ionic gradients and emerging role as a signaling molecule, changes in ATP1A3 yields insights into the mechanisms associated with HAND and interactions with drugs of abuse.  相似文献   
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