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101.
The nonenzymatic browning of dried red peppers was studied under various water activities, storage temperatures, and packaging atmospheres. Whole pepper and pepper powders-coarse and fine, with and without seeds-were compared. The browning can be described by the zero order reaction, and the rate constant is strongly affected by water activity and temperature. Flushing the package with nitrogen did not have a significant effect on the browning rate. For minimum browning, the peppers should be stored at water activities below 0.3 and in the form of whole pods or coarse powder with seeds. 相似文献
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YOUNG-NAM KIM SEONG-IL HEO MYEONG-HYEON WANG 《Journal of Food Processing and Preservation》2009,33(1):87-104
Fibrinolytic, antigenotoxic and immunomodulating properties of chungkukjang were evaluated. The purified fibrinolytic enzyme was characterized as an alkaline serine protease with molecular weight of 22 kDa determined by fibrin zymography and stable over pH range 6.0–10.0 below 50C. The comet assay showed that N-methyl-N ' -nitro-N-nitrosoguanidine (MNNG)-induced DNA damage level (190.8 AU) in 3T3 cells was considerably decreased to 121.2 AU with chungkukjang extracts (CB) showing 49.7% of protection. Incubation of the 3T3 cells with CB significantly reduced the cytotoxicity of MNNG. [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) assay revealed that the addition of CB enhanced the proliferation of RAW 264.7 (mouse leukemic monocyte macrophage cell line) macrophages up to about 150% of the control levels. RAW 264.7 macrophages incubated with CB induced a strong increase in nitric oxide (NO), tumor necrosis factor -α (TNF-α) and interleukin-1α (IL-1α) with a dose-dependent manner. After 24 h incubation with 1 mg/mL of CB, NO, TNF-α and IL-1α showed the highest production of 511, 2.46 and 0.258 ng/mL, respectively. 相似文献
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Microsporidia, as a group, cause a wide range of infections, though two species of microsporidia in particular, Enterocytozoon bieneusi and Encephalitozoon intestinalis, are associated with gastrointestinal disease in humans. To date, the mode of transmission and environmental occurrence of microsporidia have not been elucidated due to lack of sensitive and specific screening methods. The present study was undertaken with recently developed methods to screen several significant water sources. Water concentrates were subjected to community DNA extraction followed by microsporidium-specific PCR amplification, PCR sequencing, and database homology comparison. A total of 14 water concentrates were screened; 7 of these contained human-pathogenic microsporidia. The presence of Encephalitozoon intestinalis was confirmed in tertiary sewage effluent, surface water, and groundwater; the presence of Enterocytozoon bieneusi was confirmed in surface water; and the presence of Vittaforma corneae was confirmed in tertiary effluent. Thus, this study represents the first confirmation, to the species level, of human-pathogenic microsporidia in water, indicating that these human-pathogenic microsporidia may be waterborne pathogens. 相似文献
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Characterization and Food Application of an Amperometric Needle-Type L-Lactate Sensor 总被引:1,自引:0,他引:1
There have been increasing needs for biosensing in the food industry because it is accurate, rapid and efficient. A needle-type L-lactate sensor with a three-layer membrane system which uses lactate oxidase as the biological component was prepared. The sensor had an optimum pH around 9–10 and an optimum temperature at 45 C. The current response was stable over 40 days and specifically responded to L-lactic acid. The sensor gave accurate L-lactate measurements in kimchi and yogurt of 187.4 ± 4.1 and 734.1 ± 34.5 mg/dL, similar to those of a spectrophotometric L-lactate kit. 相似文献