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141.
Yong Suk Chung Nicholas J. Goeser Xingkui Cai Shelley Jansky 《American Journal of Potato Research》2013,90(4):351-356
Bacterial soft rot is a serious disease in potato (Solanum tuberosum L.), causing rapid tuber tissue maceration and, consequently, marketable yield loss. Soft rot bacteria, including Pectobacterium carotovorum subsp. carotovorum (Pbc), are favored by moist conditions, which are prevalent in large potato storage facilities. However, although most potatoes in North America are stored before use, there are no published surveys of soft rot resistance in cultivars exposed to long-term storage conditions. Thus, we tested 65 cultivars and 13 breeding lines for soft rot resistance after 6 months of storage. There was a significant effect of cultivar and production environment on soft rot resistance score. During 6 months of storage, tuber soft rot resistance in resistant clones did not change, while it changed in susceptible clones. The three most resistant cultivars to soft rot were Freedom Russet, Anett, and Alaska Red Eye. 相似文献
142.
Chitin and chitosan have been extensively investigated as a matrix of organic/inorganic composite. Barium, one of the radiopaque inorganic materials, can provide chitosan with radiopaque property by blending of chitosan and BaSO4. The filtered and deaerated chitosan/BaCl2 solutions were extruded into NaOH and Na2SO4 coagulation bath through a nozzle by gear pump. BaSO4 was synthesized by the reaction between BaCl2 and Na2SO4 in the coagulation bath, in which acidic chitosan solution was also solidified at the same time. In XRD, the introduction of BaSO4 into chitosan fibers reduced the inherent peak of chitosan fibers. In angiographic observation, chitosan/BaSO4 hybrid fibers exhibited the clear contrast images which become clear with an increase in BaSO4 content. 相似文献
143.
This study aimed to investigate the efficacy of banana peel extract as a possible substitute for the environmentally unfavorable sodium dithionite in cellulosic fiber dyeing with indigo. Antioxidant activity and total sugar content of the banana peel extract were measured. Composition of the extract was investigated by GC/MS analysis. Its reducing power for synthetic indigo was evaluated by reduction potential measurements and dyeing tests. It was shown that the studied extract could be applied successfully in the reduction of indigo in spite of their lower reducing power when compared with that of sodium dithionite. In dyeing study, sodium dithionite showed its superiority in term of reducing power over the studied extract but the studied extract was superior stability of reduction to sodium dithionite. So, it can be concluded that banana peel extract could be a biodegradable and sustainable alternative to sodium dithionite as a reducing agent in indigo dyeing processes. 相似文献
144.
Yong-Chan Chung Jae Won Choi Young Jae Jung Samsook Han Byoung Chul Chun 《Fibers and Polymers》2013,14(12):2069-2076
Polyurethane (PU) copolymer is laterally linked with three kinds of metal ion indicator (calcein, calmagite, or eriochrome black T), with which free metal ion in aqueous solution is intended to be detected by PU color change. Metal ion detection by the indicator-PU fails due to the poor permeation of hydrophilic metal ion into hydrophobic PU layer. Instead, three surfactants with different ionic head groups, aerosol OT (AOT), cetyltrimethylammonium bromide (CTAB), and sodium dodecylsulfate (SDS), are tested for metal ion. Cationic CTAB exhibits an instant PU color change, but anionic AOT and SDS do not respond at all. Reason for the selective detection of cationic surfactant is the complex formation between cationic surfactant and indicator. Molecular interactions between PUs are affected by the laterally linked indicators based on the results by infrared spectra and differential thermal analysis. UV-vis spectra reveal that extra peak arising from the linked indicator appears compared to plain PU. The lateral linking of indicator to PU demonstrates, as well as the selective surfactant detection, a 454 % increase in tensile strength and reproducible shape recovery as high as 99 % compared to plain PU. 相似文献
145.
Woochul Chang Chang Youn Lee Jun-Hee Park Moon-Seo Park Lee-So Maeng Chee Soon Yoon Min Young Lee Ki-Chul Hwang Yong-An Chung 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(1):69-76
The use of mesenchymal stem cells (MSCs) has emerged as a potential new treatment for myocardial infarction. However, the poor viability of MSCs after transplantation critically limits the efficacy of this new strategy. The expression of microRNA-210 (miR-210) is induced by hypoxia and is important for cell survival under hypoxic conditions. Hypoxia increases the levels of hypoxia inducible factor-1 (HIF-1) protein and miR-210 in human MSCs (hMSCs). miR-210 positively regulates HIF-1α activity. Furthermore, miR-210 expression is also induced by hypoxia through the regulation of HIF-1α. To investigate the effect of miR-210 on hMSC survival under hypoxic conditions, survival rates along with signaling related to cell survival were evaluated in hMSCs over-expressing miR-210 or ones that lacked HIF-1α expression. Elevated miR-210 expression increased survival rates along with Akt and ERK activity in hMSCs with hypoxia. These data demonstrated that a positive feedback loop involving miR-210 and HIF-1α was important for MSC survival under hypoxic conditions. 相似文献
146.
Jae-Ku Oem Joon-Yee Chung Mee-Soon Kwon Toh-Kyung Kim Tae-Uk Lee You-Chan Bae 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(1):91-94
Culicoides biting midges were collected on three cattle farms weekly using light traps overnight from May to October between 2010 and 2011 in the southern part of Korea. The seasonal and geographical abundance of Culicodes spp. were measured. A total of 16,538 biting midges were collected from 2010 to 2011, including seven species of Culicoides, four of which represented 98.42% of the collected specimens. These four species were Culicodes (C.) punctatus (n = 14,413), C. arakawae (n = 1,120), C. oxystoma (n = 427), and C. maculatus (n = 318). C. punctatus was the predominant species (87.15%). 相似文献
147.
Penicillinolide A: A New Anti-Inflammatory Metabolite from the Marine Fungus Penicillium sp. SF-5292
Dong-Sung Lee Wonmin Ko Tran Hong Quang Kyoung-Su Kim Jae Hak Sohn Jae-Hyuk Jang Jong Seog Ahn Youn-Chul Kim Hyuncheol Oh 《Marine drugs》2013,11(11):4510-4526
In the course of studies on bioactive metabolites from marine fungi, a new 10-membered lactone, named penicillinolide A (1) was isolated from the organic extract of Penicillium sp. SF-5292 as a potential anti-inflammatory compound. The structure of penicillinolide A (1) was mainly determined by analysis of NMR and MS data and Mosher’s method. Penicillinolide A (1) inhibited the production of NO and PGE2 due to inhibition of the expression of iNOS and COX-2. Penicillinolide A (1) also reduced TNF-α, IL-1β and IL-6 production, and these anti-inflammatory effects were shown to be correlated with the suppression of the phosphorylation and degradation of IκB-α, NF-κB nuclear translocation, and NF-κB DNA binding activity. In addition, using inhibitor tin protoporphyrin (SnPP), a competitive inhibitor of HO activity, it was verified that the inhibitory effects of compound 1 on the production of pro-inflammatory mediators and NF-κB DNA binding activity were partially associated with HO-1 expression through Nrf2 nuclear translocation. 相似文献
148.
Chung Sarit Takeuchi Junichiro Fujihara Masayuki Oeurng Chantha 《Paddy and Water Environment》2019,17(2):255-263
Paddy and Water Environment - In Cambodia, rice production is important for the majority of rural populations as the main source of income. However, historical extreme flood events, especially the... 相似文献
149.
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
150.
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