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991.
992.
Shin-Young Park Tae-Min Kang Min-Ju Kim 《Bioscience, biotechnology, and biochemistry》2013,77(11):2000-2006
ABSTRACTThe aim of this study was to investigate the effect of juicer type (blender or LSM household juicer) on the browning reaction of apple juice and evaluate the remaining antioxidant activity in the juice. The blender apple juice showed a darker brown color and 4.5 times higher PPO activity than LSM apple juice. This result suggested that the blender caused severer damage to plastids in cells leading to leakage of PPO into the juice than the LSM juicer. The total polyphenol and flavonoid content of LSM apple juice was approximately 2 times higher than that of blender apple juice because polyphenols and flavonoids can be used as substrates by PPO. The antioxidant activity of LSM juice was higher than that of blender juice. Together, these results suggested that the LSM juicer is superior to the blender for preparation of fresh apple juices due to the minimization of enzymatic oxidation reactions.Abbreviations: LSM: low-speed masticating; PPO: polyphenol oxidase; ABTS: 2,2?-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid); DPPH: 2,2-diphenyl-1-picrylhydrazyl 相似文献
993.
Norihide Hinomoto Tomomi Higaki Junichiro Abe Masafumi Yamane Eizi Yano 《Applied Entomology and Zoology》2012,47(2):165-171
We have developed and characterized 21 microsatellite markers in the aphidophagous gall midge Aphidoletes aphidimyza (Rondani) (Diptera: Cecidomyiidae). All 21 loci tested were polymorphic: the number of alleles ranged from 2 to 17. Allelic
richness and observed heterozygosities were higher in females than in males. Several loci had no heterozygosity in males,
suggesting that the loci were located on sex chromosomes or E-chromosomes, common to cecidomyiids. The high polymorphism detected
in this study suggests the markers will be of value in analyzing genetic structure of field populations. 相似文献
994.
995.
996.
Leonardo Mata Helena Gaspar Fátima Justino Rui Santos 《Journal of applied phycology》2011,23(5):827-832
The genus Asparagopsis is a prolific source of halogenated metabolites. Due to its commercial applications, it has been intensively cultivated in
southern Portugal. In the present study, we assess if the internal levels of the major halogenated metabolites (bromoform
and dibromoacetic acid) in Asparagopsis taxiformis can be increased with hydrogen peroxide (H2O2) addition. Previous studies with red algae showed that the production/release of bromoform can be enhanced by exogenously
supplying H2O2. However, no study has assessed if H2O2 supply enhances the content of secondary metabolites within the biomass. This detail is important as the objective of the
proposed research is to enhance the content of these valuable metabolites in the produced biomass. Both the activity of the
haloperoxidase enzyme and the metabolite content were assessed on short-term and long-term incubation periods to H2O2. To determine the susceptibility of A. taxiformis photosynthetic performance to the imposed oxidative stress, the in vivo fluorescence of photosystem II was monitored. A. taxiformis was shown to be physiologically vulnerable to H2O2, given the observed decrease of the maximum quantum yield of photosynthesis (F
v/F
m). Contrary to what was expected, the presence of H2O2 inhibited the activity of the iodoperoxidase enzyme. Nevertheless, the extracted halogenated metabolites were higher over
the first hours of exposure to H2O2, decreasing after 48 h. These results are probably related to the prosthetic group of the halogenated enzyme in A. taxiformis and the long-term oxidative stress damage of H2O2 exposure. Considering the objective of the proposed research, addition of H2O2 to the cultures, prior (3 h) to biomass harvesting, increases the metabolite content. 相似文献
997.
Food restriction (FR) is hypothesized to decrease body fat content of an animal and thus prevent obesity. However, the response
of energy budget to a continuous (CFR) or discontinuous FR (DFR) remains inconsistent. In the present study, effects of CFR
or DFR and refeeding on energy budget and behavior were examined in male Swiss mice. CFR significantly decreased the energy
expenditure associated with basal metabolic rate (BMR) and activity behavior, but not sufficiently to compensate for energy
deficit and thus resulted in lower body mass and fat content. DFR mice had a significantly higher food intake on ad libitum
days and showed increases in BMR and activity after 4 weeks’ DFR, which might resulted in lower body mass and less body fat
than controls. After being refed ad libitum, both CFR and DFR mice had similar body mass, BMR, and behavioral patterns to
controls but had 95% and 75% higher fat content. This suggested that not only CFR but also DFR would be a significant factor
in the process of obesity for animals that were refed ad libitum. It also indicated that food restriction interrupted many
times by periods of ad libitum feeding had the same long-term effects like continuous underfeeding. 相似文献
998.
There is a strong need to develop novel strategies in using antiviral agents to efficiently treat influenza infections. Thus, we constructed a rule-based mathematical model that reflects the complicated interactions of the host immunity and viral life cycle and analyzed the key controlling steps of influenza infections. The main characteristics of the pandemic and seasonal influenza strains were estimated using parameter values derived from cells infected with Influenza A/California/04/2009 and Influenza A/NewCaledonia/20/99, respectively. The quantitative dynamics of the infected host cells revealed a more aggressive progression of the pandemic strain than the seasonal strain. The perturbation of each parameter in the model was then tested for its effects on viral production. In both the seasonal and pandemic strains, the inhibition of the viral release (kC), the reinforcement of viral attachment (kV), and an increased transition rate of infected cells into activated cells (kI) exhibited significant suppression effects on the viral production; however, these inhibitory effects were only observed when the numerical perturbations were performed at the early stages of the infection. In contrast, combinatorial perturbations of both the inhibition of viral release and either the reinforcement of the activation of infected cells or the viral attachment exhibited a significant reduction in the viral production even at a later stage of infection. These results suggest that, in addition to blocking the viral release, a combination therapy that also enhances either the viral attachment or the transition of the infected cells might provide an alternative for effectively controlling progressed influenza infection. 相似文献
999.
1000.
Seung U. Kim 《Histochemistry and cell biology》1976,48(3):205-217
Summary Explants of 10–12 day chick embryo spinal cord were cultured by coverslip-roller tube method for 3–80 days. The cellular and subcellular localization of acetylcholinesterase activity in cultured neurons was studied by the thiocholine techniques of Karnovsky and Roots and Lewis and Shute.At the light microscopic level, acetylcholinesterase was demonstrated in the neurons of both ventral and dorsal horn regions. Occasionally neurons migrated in the outgrowth zone exhibited strong intracellular activity.At the electron microscopic level, acetylcholinesterase activity was found in the nuclear envelope, granular endoplasmic reticulum and the Golgi apparatus of the neurons. No enzyme reaction was detected in the glial cell cytoplasm. 相似文献