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Dong-Lin Wang Ahindra Nag Guan-Chun Lee Jei-Fu Shaw 《Journal of agricultural and food chemistry》2002,50(2):262-265
Among 10 lipases tested, Candida rugosa lipase exhibited the best ability to catalyze the resolution of dl-menthol in organic solvent. The lipase was immobilized on different carriers, and the experiment was carried out with different acyl donors. The high yield and optical purity of the product were achieved in cyclohexane with valeric acid as acyl donor using C. rugosa lipase immobilized on DEAE-Sephadex A-25. The conversion of dl-menthol depended on the water content of immobilized lipase and on the pH of the aqueous solution from which lipase was immobilized. The operational stability of the DEAE-Sephadex A-25 immobilized lipase in catalysis of the esterification reaction showed that >85% activity remained after 34 days of repeated use. The resolution of racemic menthol in organic medium catalyzed by immobilized C. rugosa lipase-catalyzed esterification is very convenient, and it represents a significant improvement in the use of enzyme for the preparative production of optically active menthol. This process is readily applicable to large-scale preparation. 相似文献
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Chung SH Kim IH Park HG Kang HS Yoon CS Jeong HY Choi NJ Kwon EG Kim YJ 《Journal of agricultural and food chemistry》2008,56(9):3311-3316
This study was performed to discover bifidobacteria isolated from human intestines that optimally convert linoleic acid (LA) to conjugated linoleic acid (CLA) and to optimize the culture conditions of milk fermentation. One hundred and fifty neonatal bifidobacteria were screened for CLA-producing ability, and Bifidobacterium breve LMC 017 was selected as it showed about 90% conversion of free LA in MRS broth. The selected strain showed resistance at 0.5% LA in microaerophillic conditions. When monolinolein (LA 90%) was used as a substrate for CLA production, the conversion rate was lower compared to free LA, but the growth rate was unaffected during the milk fermentation. There was no significant difference in CLA production between aerobic and anaerobic conditions, and little decline in CLA was shown after the maximal CLA level had been reached. CLA production increased by 80% with 24 h of incubation in milk containing additional skim milk (5%), where the proteins may have facilitated the production of CLA by enhancing the interaction of substrate with the bacteria. CLA production did not decline after 9 h of fermentation and an additional 12 weeks of storage with other commercial starters. This demonstrates the possibility of using this strain as a costarter in the production of CLA-enriched yogurt. 相似文献
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Choi NJ Park HG Kim YJ Kim IH Kang HS Yoon CS Yoon HG Park SI Lee JW Chung SH 《Journal of agricultural and food chemistry》2008,56(22):10908-10912
This study was designed to isolate bifidobacteria from human intestines that efficiently converts monolinolein, a monoglyceride form of linoleic acid, into conjugated linoleic acid (CLA), as well as to optimize culture conditions for improving CLA production during milk fermentation. Among 150 screened neonatal bifidobacteria, Bifidobacterium breve LMC 520 showed the highest CLA-producing ability and was tested with different types of fat substrates at various concentrations to determine the optimal conditions for CLA production. Monolinolein was tested as a substrate for CLA production. The incubation time optimized for CLA production was 24 h, and CLA production was proportionally increased with monolinolein concentration. The incubation of LMC 520 with commercial starter strains caused minimal reduction in CLA production. Our results demonstrate that the CLA-producing ability of B. breve LMC 520 could offer beneficial effects when utilized as a starter culture for the development of functional dairy products. 相似文献
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A. Dewanji S. Matai L. Si S. Barik A. Nag 《Plant foods for human nutrition (Dordrecht, Netherlands)》1993,44(1):11-16
The seasonal variation in the nutrient composition ofEnhydra fluctuans andMarsilea quadrifolia, two edible semi-aquatic plants, was studied in order to promote their consumption as green leafy vegetables. Both plants had a high crude protein content throughout all harvesting seasons.Enhydra fluctuans had a low ash content and was a good source of -carotene (3.7 to 4.2 mg/100 g on a fresh weight basis).Marsilea quadrifolia exhibited wide fluctuations between seasons and was not very promising in nutrient composition when compared to other commonly used green leafy vegetables. 相似文献
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Sundaresan NR Saxena VK Sastry KV Anish D Marcus Leo MD Kantaraja C Saxena M Ahmed KA 《Veterinary research communications》2008,32(1):13-19
Chicken postovulatory follicle (POF) regression occurs via the process of apoptosis. However, the signals and initiator pathways
responsible for regression of the POF are unknown. In the current study, we examined gene expression patterns of various caspases
(caspase-1, -2 and -3) involved in apoptosis by semi-quantitative RT-PCR. The percentage of apoptotic cells during POF regression
was also quantified by flow cytometry. Expression of caspase-3 mRNA was noted in the largest preovulatory follicle (F1). However,
the initiator caspases (caspase-1 and -2) were not expressed in F1. During the regression of the POF, caspase-3 was activated
during initial stages, whereas the initiator caspases were upregulated at the later stages (POF4 and POF5).The percentage
of apoptotic cells was significantly higher during the regression of the POF. It might be possible that levels of caspase-3
mRNA do not necessarily reflect the cell’s potential for facilitating apoptosis, as activation of the caspase-3 by initiator
caspases is required for its function. We presume that both caspase-1 and caspase-2 were key initiators in the regression
of chicken POF and that the apoptosis-mediated regression of POFs might be similar to mammalian corpus luteum involution. 相似文献
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Clark AG Glanowski S Nielsen R Thomas PD Kejariwal A Todd MA Tanenbaum DM Civello D Lu F Murphy B Ferriera S Wang G Zheng X White TJ Sninsky JJ Adams MD Cargill M 《Science (New York, N.Y.)》2003,302(5652):1960-1963
Even though human and chimpanzee gene sequences are nearly 99% identical, sequence comparisons can nevertheless be highly informative in identifying biologically important changes that have occurred since our ancestral lineages diverged. We analyzed alignments of 7645 chimpanzee gene sequences to their human and mouse orthologs. These three-species sequence alignments allowed us to identify genes undergoing natural selection along the human and chimp lineage by fitting models that include parameters specifying rates of synonymous and nonsynonymous nucleotide substitution. This evolutionary approach revealed an informative set of genes with significantly different patterns of substitution on the human lineage compared with the chimpanzee and mouse lineages. Partitions of genes into inferred biological classes identified accelerated evolution in several functional classes, including olfaction and nuclear transport. In addition to suggesting adaptive physiological differences between chimps and humans, human-accelerated genes are significantly more likely to underlie major known Mendelian disorders. 相似文献
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Nidhi Shrivastava Prashant Kumar Singh Jeetendra Kumar Nag Susheela KushwahaShailja Misra-Bhattacharya 《Comparative immunology, microbiology and infectious diseases》2013
Although recombinant vaccines have several advantages over conventional vaccines, protection induced by single antigen vaccines is often inadequate for a multicellular helminth parasite. Therefore, immunoprophylactic efficacy of cocktail antigen vaccines comprised of several combinations of three Brugia malayi recombinant proteins BmAF-Myo, Bm-iPGM and Bm-TPP were evaluated. Myosin + TPP and iPGM + TPP provided the best protection upon B. malayi infective larval challenge with ∼70% reduction in adult worm establishment over non-vaccinated animals that was significantly higher than the protection achieved by any single antigen vaccine. Myosin + iPGM, in contrast did not provide any enhance protection over the single recombinant protein vaccines. Specific IgG, IgM level, IgG antibody subclasses levels (IgG1, IgG2a, IgG2b, IgG3), lymphocyte proliferation, reactive oxygen species level and cytokines level were also determined to elucidate the characteristics of the protective immune responses. Thus the study undertaken provided more insight into the cocktail vaccination approach to combat LF. 相似文献
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Sultan Singh Subir Kumar Nag Subhendu Bikash Maity Badri Prasad Kushwaha 《Tropical animal health and production》2012,45(1):251-257
A study was undertaken to evaluate the nutritional response of organically grown diets in buffaloes on nutrients utilization and nutrient efficiency for milk production. For this, ten milch Murrah buffaloes of average body weight (490.72?±?6.65 kg), milk yield (8.13?±?0.33 kg), and lactation stage (85?±?5.28 days) were distributed in inorganic (InDg) and organic dietary groups (OrDg) with five animals in each. Buffaloes of InDg and OgDg were fed sorghum hay–berseem fodder-concentrate mixture-based diets grown inorganically and organically, respectively. After 60 days of feeding, a digestion cum metabolism trial was conducted to assess feed intake, nutrient utilization, and N balance, while milk yield and composition were recorded fortnightly. DM, CP, digestible crude protein (DCP), and metabolizable energy (ME) intake (g/Kg w0.75) were similar in animals of InDg and OrDg. NDF, ADF, and hemicellulose digestibility were (P?<?0.05) higher in animals on OrDg (59.20, 51.55, and 62.67) than InDg diet (54.57, 43.72, and 56.61 %), respectively. Urinary n loss (g/day) was (P?<?0.05) lower in OrDg (67.23) than in InDg (83.55); however, milk N was comparable in animals of both dietary groups (47.36 vs 45.82 g/day). Nitrogen balance was higher in animals of OrDg (39.72) than in InDg (28.08). DCP, TDN, and ME values of both diets were similar. No effect of diet was observed on milk yield and its composition; however, increased lactation length decreased milk yield. Buffaloes on both diets had similar efficiency and conversion ratio of nutrients for milk production. Results revealed that diets (organically vs. inorganically grown) have no effect on milk yield and its composition; however, buffaloes on organic diet have higher fiber digestibility and low urinary N loss which did not affect the dietary nutrients efficiency and conversion ratio for milk production. 相似文献