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941.
Juan Mao Sung Wook Won Yeoung-Sang Yun 《World journal of microbiology & biotechnology》2009,25(7):1259-1266
A low cost biosorbent, Corynebacterium glutamicum, was studied for the sorption of Reactive Red 4 (RR 4) and Methylene Blue (MB). The equilibrium isotherm data were well described
by the Langmuir model. pH edge experiments showed that pH of the solution was an important controlling parameter in the sorption
process. In the case of RR 4, with increases in the pH from 2 to 10, the uptake decreased from 52 to 1 mg/g; conversely, the
uptake of MB increased and the maximum MB uptake was obtained at pH ≥ 9. An increase in the salt concentration strongly influenced
the uptake of MB, but had no effect on that of RR 4. In order to identify the binding sites for the dye molecules, the biosorbent
was potentiometrically titrated, the results of which showed the presents of four major functional group types on the biomass
surface, which were confirmed by FTIR analysis. It was found that positively charged amine groups (Biomass-NH3
+) were the likely binding sites for anionic RR 4, and negatively charged carboxyl (Biomass-COO−) and phosphate groups (Biomass-HPO4
−) played a role in the electrostatic attraction of cationic MB. 相似文献
942.
A small-silo study was conducted to develop an effective ensiling storage method for the use of cotton waste-based spent mushroom substrate (SMS) as an animal feed. The SMS was ensiled with 5% molasses (DM basis), 0.5% (v/w) lactic acid bacteria (LAB, Lactobacillus plantarum) inoculant or 0.5% (v/w) yeast (Saccharomyces cerevisiae) inoculant. The treatments included 100% SMS (control), 95% SMS+5% molasses (T1), 95% SMS+5% molasses+0.5% LAB (T2) and 95% SMS+5% molasses+5% LAB+0.5% yeast (T3). The treatments were ensiled for 10. Change in chemical compositions was little (P>0.05) according to the ensiling process and treatments. Compared with those before ensiling, 100% SMS (control) after ensiling showed unstable fermentative properties with high pH (5.2) and little lactic acid production. Compared with the ensiled control, treatments (T1, T2 and T3) resulted in decreased pH, 18-20 times higher concentrations of lactic acid, and greater populations of total bacteria (P<0.07), LAB and yeast (P<0.07). The addition of 5% molasses, 0.5% LAB and 0.5% yeast (T3) to the SMS resulted in the lowest pH (4.25) and the greatest microbial populations. Treatment T3 was selected for a large scale silo study which was ensiled for 10, 20 and 30 d. As in the small-silo study, the T3 treatment showed favorable fermentative and microbial parameters, compared with the control, by decreasing pH and increasing lactic acid concentrations, LAB and yeast populations. The minimum ensiling period was 20 d, when pH was reasonably low and LAB and yeast populations were greatest. In conclusion, molasses and microbial inoculation improved silage quality of SMS. 相似文献
943.
Yan Ding Huu Tung Nguyen Sung In Kim Ha Won Kim Young Ho Kim 《Bioorganic & medicinal chemistry letters》2009,19(13):3607-3610
In our preliminary screening study on the anti-inflammatory activity, eight triterpenes, one sterol, and one chalcone were isolated from the CH2Cl2-soluble extract of the stems and leaves of Rhus sylvestris Siebold and Zucc (Anacardiaceae). On the basis of their spectroscopic data, these compounds were identified as 10α-cucurbitadienol (1), glut-5-en-3-ol (2), β-amyrin acetate (3), β-amyrin (4) and lupeol (5), cycloart-24-en-3-one (6), cycloart-25-en-3,24-dione (7), 24-hydroxycycloart-25-en-3-one (8), β-sitosterol (9), and 2′-hydroxy-4,4′-dimethoxychalcone (10). All of them were isolated from this plant for the first. Furthermore, the compounds in non-cytotoxic concentrations (0–1.0 μM) were tested for their ability to block inflammatory cytokine secretion in the presence of LPS in the murine RAW264.7 macrophage cell line. Among the compounds that were tested, compounds 8 and 9 reduced the LPS-induced secretion of IL-6, as well as TNF-α, in a mouse RAW264.7 macrophage cell line. Moreover, compounds 2, 3, 7, and 10 specifically diminished only the secretion of TNF-α even in 0.01 μM concentrations. It is thus suggested that they are potential therapeutics of TNF-α-related diseases and conditions, such as transplant rejection, type II diabetes, and atherosclerosis. 相似文献
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946.
Koh CJ Delo DM Lee JW Siddiqui MM Lanza RP Soker S Yoo JJ Atala A 《Methods (San Diego, Calif.)》2009,47(2):90-97
Embryonic stem cells are envisioned as a viable source of pluripotent cells for use in regenerative medicine applications when donor tissue is not available. However, most current harvest techniques for embryonic stem cells require the destruction of embryos, which has led to significant political and ethical limitations on their usage. Parthenogenesis, the process by which an egg can develop into an embryo in the absence of sperm, may be a potential source of embryonic stem cells that may avoid some of the political and ethical concerns surrounding embryonic stem cells. Here we provide the technical aspects of embryonic stem cell isolation and expansion from the parthenogenetic activation of oocytes. These cells were characterized for their stem-cell properties. In addition, these cells were induced to differentiate to the myogenic, osteogenic, adipogenic, and endothelial lineages, and were able to form muscle-like and bony-like tissue in vivo. Furthermore, parthenogenetic stem cells were able to integrate into injured muscle tissue. Together, these results demonstrate that parthenogenetic stem cells can be successfully isolated and utilized for various tissue engineering applications. 相似文献
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949.
Won Jun Choi Hyuk Woo Lee Hea Ok Kim Moshe Chinn Zhan-Guo Gao Amit Patel Kenneth A. Jacobson Hyung Ryong Moon Young Hoon Jung Lak Shin Jeong 《Bioorganic & medicinal chemistry》2009,17(23):8003-8011
On the basis of a bioisosteric rationale, 4′-thionucleoside analogues of IB-MECA (N6-(3-Iodo-benzyl)-9-(5′-methylaminocarbonyl-β-d-ribofuranosyl)adenine), which is a potent and selective A3 adenosine receptor (AR) agonist, were synthesized from d-gulonic acid γ-lactone. The 4′-thio analogue (5h) of IB-MECA showed extremely high binding affinity (Ki = 0.25 nM) at the human A3AR and was more potent than IB-MECA (Ki = 1.4 nM). Bulky substituents at the 5′-uronamide position, such as cyclohexyl and 2-methylbenzyl, in this series of 2-H nucleoside derivatives were tolerated in A3AR binding, although small alkyl analogues were more potent. 相似文献
950.