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991.
Clegg IM Daly AM Donnelly C Hardy R Harris D Jackman H Jones R Luan A McAndrew D McGauley P Pearce J Scotney G Yeow ML 《Applied spectroscopy》2012,66(5):574-579
The use of in situ mid-infrared spectroscopy to support the development of a pharmaceutical manufacturing process is disclosed. Data on this two-stage telescoped reaction from several reaction scales (<50 mL to 1600 liters) and at multiple manufacturing locations is shown. In addition to providing data on both reactions in the telescope, the mid-IR data has been used to monitor an intermediate distillation operation and therefore it has been possible to profile the whole process. Data is also shown on aliquot addition during the first chemical transformation, which is used to check the instrumentation. 相似文献
992.
Jonathan T Vogel Denise M Tieman Charles A Sims Asli Z Odabasi David G Clark Harry J Klee 《Journal of the science of food and agriculture》2010,90(13):2233-2240
BACKGROUND: Tomatoes contain high levels of several carotenoids including lycopene and β‐carotene. Beyond their functions as colorants and nutrients, carotenoids are precursors for important volatile flavor compounds. In order to assess the importance of apocarotenoid volatiles in flavor perception and acceptability, we conducted sensory evaluations of near‐isogenic carotenoid biosynthetic mutants and their parent, Ailsa Craig. RESULTS: The carotenoid contents of these tomatoes were extremely low in the r mutant, increased in lycopene in old gold, and higher in tetra‐cis‐lycopene and ζ‐carotene in tangerine. The volatiles derived from these carotenoids (β‐ionone, geranylacetone and 6‐methyl‐5‐hepten‐2‐one) were proportionally altered relative to their precursors. Fruits were also analyzed for soluble solids, sugars, acids and flavor volatiles. Consumer panels rated the r mutant lowest for all sensory attributes, while Ailsa Craig was generally rated highest. Old gold and tangerine were rated intermediate in two of the three harvests. CONCLUSIONS: Several chemicals were negatively correlated with at least one of the hedonic scores while several others were positively correlated with tomato flavor acceptability. The results permitted identification of positive and negative interactions of volatiles with tomato flavor. Copyright © 2010 Society of Chemical Industry 相似文献
993.
Thermophilic bacilli and their importance in dairy processing 总被引:1,自引:0,他引:1
The thermophilic bacilli, such as Anoxybacillus flavithermus and Geobacillus spp., are an important group of contaminants in the dairy industry. Although these bacilli are generally not pathogenic, their presence in dairy products is an indicator of poor hygiene and high numbers are unacceptable to customers. In addition, their growth may result in milk product defects caused by the production of acids or enzymes, potentially leading to off-flavours. Dairy thermophiles are usually selected for by the conditions during dairy manufacture. These bacteria are able to grow in sections of dairy manufacturing plants where temperatures reach 40-65 °C. Furthermore, because they are spore formers, they are difficult to eliminate. In addition, they exhibit a wide temperature growth range, exhibit a fast growth rate (generation time of approximately 15-20 min) and tend to readily form biofilms. Many strategies have been tested to remove, prevent and/or delay the formation of thermophilic bacilli biofilms in dairy manufacture, but with limited success. This is, in part, because little is known about the structure and composition of thermophilic bacilli biofilms in general and, more specifically, in milk processing environments. Therefore, new cleaning regimes often do not target the problem optimally. A greater understanding of the structure of thermophilic biofilms within the context of the milk processing environment and their link with spore formation is needed to develop better control measures. This review discusses the characteristics and food spoilage potential, enumeration and identification methods for the thermophilic bacilli, as well as their importance to dairy manufacture, with an emphasis on biofilm development and spore formation. 相似文献
994.
Tong DQ Muller NZ Mauzerall DL Mendelsohn RO 《Environmental science & technology》2006,40(5):1395-1400
This paper examines the ozone (O3) damages caused by nitrogen oxides (NO(x)) emissions in different locations around the Atlanta metropolitan area during a summer month. We calculate O3 impacts using a new integrated assessment model that links pollution emissions to their chemical transformation, transport, population exposures, and effects on human health. We find that increased NO(x) emissions in rural areas around Atlanta increase human exposure to ambient O3 twice as much as suburban emissions. However, increased NO(x) emissions in central city Atlanta actually reduce O3 exposures. For downtown emissions, the reduction in human exposures to O3 from titration by NO in the central city outweighs the effects from increased downwind O3. The results indicate that the marginal damage from NO(x) emissions varies greatly across a metropolitan area. The results raise concerns if cap and trade regulations cause emissions to migrate toward higher marginal damage locations. 相似文献
995.
alpha-Pinene is the dominant monoterpene in Juniperus monosperma. Wood rat species in the genus Neotoma that consume J. monosperma vary in their inclusion of it in their wild diet and in their tolerance of whole J. monosperma or alpha-pinene in laboratory feeding trials. A proposed mechanism for variable tolerance is a difference in absorption of alpha-pinene from the small intestine that is mediated by the intestinal transporter permeability glycoprotein (Pgp). To determine if alpha-pinene is a Pgp substrate, we tested whether it can competitively inhibit Pgp and thereby increase the accumulation of a known Pgp substrate (digoxin) in (1) everted sleeves of small intestine from Neotoma stephensi, a juniper specialist, N. albigula, a sympatric generalist that consumes juniper, N. cinerea, a more distantly related generalist, and Sprague-Dawley rats, and (2) in Caco-2 cells that over express Pgp. We also measured Pgp ATPase phosphate production in transfected insect membrane vesicles exposed to alpha-pinene. We found no significant increase in digoxin accumulation with competitive inhibition experiments, and no increase in phosphate production with transfected membranes, at any concentration of alpha-pinene up to 100 μM. To test whether other compounds in juniper affect Pgp activity, we acclimated five N. stephensi to a juniper diet for 5 d, but found no significant effect compared to animals on control diet. Our data suggest that alpha-pinene is not a Pgp substrate. 相似文献
996.
James S Moehle K Renard A Mueller MS Vogel D Zurbriggen R Pluschke G Robinson JA 《Chembiochem : a European journal of chemical biology》2006,7(12):1943-1950
The Plasmodium falciparum merozoite surface protein-1 19 kDa fragment (MSP-1(19)) comprises two closely packed EGF-like domains (EGF=epidermal growth factor), each stabilized by three disulfide bonds. The native conformation of this protein is important for eliciting P. falciparum growth inhibitory antibodies. Here we show that the N-terminal EGF domain alone can be chemically synthesized and efficiently refolded to a native-like state, as shown by its solution structure as determined by NMR spectroscopy. In order to study its immunogenicity, the domain was coupled through its N terminus to a phospholipid and incorporated into reconstituted influenza virus-like particles (virosomes). When used to immunize mice, the peptide-loaded virosomes elicited potent humoral immune responses that were shown by Western blots and immunofluorescence assays to cross-react with native MSP-1 on the surfaces of P. falciparum blood stage parasites. This opens the way for a medicinal chemistry-oriented approach to the study and optimization of the antigenicity of the protein as a potential malaria vaccine candidate, whilst exploiting the immunopotentiating properties of influenza virosomes as a delivery vehicle. 相似文献
997.
998.
Miguel Antonio Soplin Pastor Amilton Barbosa Botelho Junior Jorge Alberto Soares Tenório Denise Crocce Romano Espinosa Marcela dos Passos Galluzzi Baltazar 《加拿大化工杂志》2023,101(4):2094-2103
Since the quality of bauxite resources has decreased and the organic carbon content has increased, different approaches are explored to remove the organic matter in alumina production. Advanced oxidative processes (AOPs) represent a possibility since they are widely used as an alternative for treating wastewaters to degrade organic pollutant molecules and in hydrometallurgy processes. For this reason, the goal of the project was the ozonation of Bayer liquor for organic matter removal. The ozone concentration was evaluated over time, as well as the H2O2 concentration and temperature. Results showed that the total organic carbon (TOC) removal achieved 19% in the most optimized condition with a kinetic rate of 0.0157 h−1 –21.9 mg/L O3, 0.05 mol/L H2O2 at 80°C. The colour of the liquor changed from dark brown to white-yellow, indicating that the size of the organic compounds had decreased. Also, 95.4% of degraded TOC formed CO2, and almost 50% of the organic matter was oxalate compounds. The energy required for ozone production versus removed organic matter demonstrated that the technique proposed might be technically and economically feasible to be applied in the Bayer process. The study demonstrates the application of AOP in an extremely alkaline condition. 相似文献
999.
The lactose-H+ symport protein (LacS) of Streptococcus thermophilus has a carboxyl-terminal regulatory domain (IIALacS) that is homologous to a family of proteins and protein domains of the phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS) in various organisms, of which IIAGlc of Escherichia coli is the best-characterized member. On the basis of these similarities, it was anticipated that IIALacS would be able to perform one or more functions associated with IIAGlc, i.e., carry out phosphoryl transfer and/or affect other catabolic functions. The gene fragment encoding IIALacS was overexpressed in Escherichia coli, and the protein was purified in two steps by metal affinity and anion-exchange chromatography. IIALacS was unable to restore glucose uptake in a IIAGlc-deficient strain, which is consistent with a very low rate of phosphorylation of IIALacS by phosphorylated HPr (HPr approximately P) from E. coli. With HPr approximately P from S. thermophilus, the rate was more than 10-fold higher, but the rate constants for the phosphorylation of IIALacS (k1 = 4.3 x 10(2) M-1 s-1) and dephosphorylation of IIALacS approximately P by HPr (k-1 = 1.1 x 10(3) M-1 s-1) are still at least 4 orders of magnitude lower than for the phosphoryltransfer between IIAGlc and HPr from E. coli. This finding suggests that IIALacS has evolved into a protein domain whose main function is not to transfer phosphoryl groups rapidly. On the basis of sequence alignment of IIA proteins with and without putative phosphoryl transfer functions and the known structure of IIAGlc, we constructed a double mutant [IIALacS(I548E/G556D)] that was predicted to have increased phosphoryl transfer activity. Indeed, the phosphorylation rate of IIALacS(I548E/G556D) by HPr approximately P increased (k1 = 4.0 x 10(3) M-1 s-1) and became nearly independent of the source of HPr approximately P (S. thermophilus, Bacillus subtilis, or E. coli). The increased phosphoryl transfer rate of IIALacS(I548E/G556D) was insufficient to complement IIAGlc in PTS-mediated glucose transport in E. coli. Both IIALacS and IIALacS(I548E/G556D) could replace IIAGlc, but in another function: they inhibited glycerol kinase (inducer exclusion) when present in the unphosphorylated form. 相似文献
1000.
Lídia M Santa Anna Adriana U Soriano Absai C Gomes Emerson P Menezes Melissa LE Gutarra Denise MG Freire Nei Pereira Jr 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2007,82(7):687-691
The effectiveness of cell‐free rhamnolipid biosurfactant, derived from the culture medium at the end of fermentation was investigated for the removal of two different kinds of oil from contaminated sandy soils. The crude cultivation medium, containing 13.2 g L?1 of rhamnolipids, had a surface tension, interfacial tension and critical micellar concentration of 30 mN m?1, 2 mN m?1 and 60 mg L?1, respectively. The evaluation of biosurfactant in the culture medium (BM) and oil concentrations in the removal of oil from different contaminated sandy soil was performed using a statistical experimental design tool. Oil in sandy soil, containing predominantly aromatic or paraffinic hydrocarbons (5 to 10% w/w), was removed by as much as 91 and 78%, respectively, in the presence of reduced amounts of BM (6.3 to 7.9 g L?1). The progress of oil removal was monitored for 101 days and results indicated that removal efficiency in sandy soil with aromatic characteristics was relatively stable over the entire period. Based on these studies, it is concluded that use of a BM was effective in reducing oil concentrations in contaminated sandy soil. Copyright © 2007 Society of Chemical Industry 相似文献