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A hybrid anaerobic solid-liquid (HASL) bioreactor is an enhanced two-phase anaerobic system, that consists of a solid waste reactor as the acidification reactor and a wastewater reactor, i.e. an upflow anaerobic sludge blanket (UASB) reactor as the methanogenic reactor. Food waste digestion in HASL bioreactors with pre-acidification and HASL operation stages was investigated in two separate runs. After 8 days of pre-acidification in Run A and 4 days in Run B, total volatile fatty acid (TVFA) and chemical oxygen demand (COD) concentrations in the leachates of both acidification reactors were similar. During HASL operation stage, TVFA and COD removal in the methanogenic phase were 77–100% and 75–95%, respectively. Some 99% of the total methane generated was from the methanogenic phase with a content of 68–70% methane. At the end of operation, about 59–60% of the added volatile solids (VS) were removed with a methane yield of 0.25 l g–1 VS. 相似文献
3.
John H. Pazur Michael E. Tay Beverly A. Pazur Frank J. Miskiel 《Journal of Protein Chemistry》1987,6(5):387-399
Sets of isomeric anti-lactose antibodies with specificity for the lactose units of a cell wall polysaccharide fromStreptococcus faecalis strain N were induced in rabbits immunized with a vaccine of nonviable cells of the organism. Such sets of anti-lactose antibodies
were isolated from the serum of immunized animals by affinity chromatography on lactosyl-Sepharose. Gel electrofocusing experiments
showed that the preparations consisted of multiprotein components. One preparation of antibodies of 13 isomers was separated
into homogeneous components by liquid isoelectrofocusing. The individual isomeric antibodies exhibit specificity for the lactose
units of the antigenic polysaccharide, possess isoelectric points in the range of 5.9–8.0, and belong to the IgG class of
immunoglobulins, and each member yields one light chain and one heavy chain on dissociation in sodium dodecyl sulfate (SDS)
and mercaptoethanol. These results have been interpreted as evidence for the assembly of the chains of isomeric antibodies
by a single-chain pairing mechanism. 相似文献
4.
The isolated kidney perfused with modified Krebs-Henseleit buffer with amino acids yields heavy proteinuria associated with reduced ATP levels characteristic of partial ischemia. These conditions are associated with a similar perfusion time dependent release of degraded vascular [35S]heparan sulfate proteoglycan into the perfusate solution which included a 60% loss of [35S]macromolecular material from the glomerulus after 2h of perfusion. Small amounts of [35S]macromolecular material were found in the urine and lymph. These results demonstrate that partial ischemia promotes a specific response in the overall renal vasculature, probably involving oxygen reactive metabolites, that results in the preferential release of heparan sulphate from the basement membrane and endothelial cells on the luminal side of the capillary wall. 相似文献
5.
S. A. B. Tay J. K. MacLeod L. M. S. Palni 《Journal of plant biochemistry and biotechnology.》1993,2(2):105-109
Cytokinin glucosides are routinely quantified as their aglycones produced by enzymic or chemical hydrolysis. It is, however, important to be able to measure their levels per se. The present paper illustrates the use of desorption chemical ionisation mass spectrometry coupled with stable isotope dilution for the determination of intact, underivatized N- and O- glucosyl conjugates of cytokinins in Datura innoxia crown gall tissue. A total of six glucosyl conjugates were determined; the two N-glucosides, zeatin-7-glucoside and zeatin-9-glucoside, were present in higher quantities than the O-glucosyl derivatives of zeatin, dihydrozeatin and their ribosides. 相似文献
6.
7.
L-Rhamnose (6-deoxy-L-mannose) is a constituent carbohydrate unit of microbial, immunogenic heteroglycans and lipopolysaccharides, and often functions as the immunodeterminant group of such immunogens. Two types of anti-rhamnose antibody have now been isolated by affinity chromatography of immune sera obtained from rabbits immunized with vaccines of Streptococcus mutans, strain KI-R, and Streptococcus pneumoniae, type 32. The antibodies of one type were directed at a glycan of L-rhamnose, D-glucose, and D-galactose in the cell wall of S. mutans, and those of the other type, against a capsular glycan of L-rhamnose and D-glucose from S. pneumoniae. The two types of anti-rhamnose antibody were immunologically distinct, and showed no reciprocal cross-reactivity. Additional properties of the two types of antibody were determined; thus, both types of antibody were of the IgG class of immunoglobulins, both possessed molecular weights of 1.45 X 10(5), and both consisted of multiple or isomeric forms. 相似文献
8.
Can Chen Yi Wang Sally S. L. Goh Jing Yang Dang Hoang Lam Yukti Choudhury Felix Chang Tay Shouhui Du Wee Kiat Tan Yovita Ida Purwanti Weimin Fan Shu Wang 《Journal of neurochemistry》2013,126(3):318-330
The breakthrough in derivation of human‐induced pluripotent stem cells (hiPSCs) provides an approach that may help overcome ethical and allergenic challenges posed in numerous medical applications involving human cells, including neural stem/progenitor cells (NSCs). Considering the great potential of NSCs in targeted cancer gene therapy, we investigated in this study the tumor tropism of hiPSC‐derived NSCs and attempted to enhance the tropism by manipulation of biological activities of proteins that are involved in regulating the migration of NSCs toward cancer cells. We first demonstrated that hiPSC‐NSCs displayed tropism for both glioblastoma cells and breast cancer cells in vitro and in vivo. We then compared gene expression profiles between migratory and non‐migratory hiPSC‐NSCs toward these cancer cells and observed that the gene encoding neuronal nitric oxide synthase (nNOS) was down‐regulated in migratory hiPSC‐NSCs. Using nNOS inhibitors and nNOS siRNAs, we demonstrated that this protein is a relevant regulator in controlling migration of hiPSC‐NSCs toward cancer cells, and that inhibition of its activity or down‐regulation of its expression can sensitize poorly migratory NSCs and be used to improve their tumor tropism. These findings suggest a novel application of nNOS inhibitors in neural stem cell‐mediated cancer therapy. 相似文献
9.
Carlota Tayà Javier Guerrero Gianni Vanneste Albert Guisasola Juan A. Baeza 《Biotechnology and bioengineering》2013,110(2):391-400
The presence of suitable carbon sources for enhanced biological phosphorus removal (EBPR) plays a key role in phosphorus removal from wastewater in urban WWTP. For wastewaters with low volatile fatty acids (VFAs) content, an external carbon addition is necessary. As methanol is the most commonly external carbon source used for denitrification it could be a priori a promising alternative, but previous attempts to use it for EBPR have failed. This study is the first successful report of methanol utilization as external carbon source for EBPR. Since a direct replacement strategy (i.e., supply of methanol as a sole carbon source to a propionic‐fed PAO‐enriched sludge) failed, a novel process was designed and implemented successfully: development of a consortium with anaerobic biomass and polyphosphate accumulating organisms (PAOs). Methanol‐degrading acetogens were (i) selected against other anaerobic methanol degraders from an anaerobic sludge; (ii) subjected to conventional EBPR conditions (anaerobic + aerobic); and (iii) bioaugmented with PAOs. EBPR with methanol as a sole carbon source was sustained in a mid‐term basis with this procedure. Biotechnol. Bioeng. 2013; 110: 391–400. © 2012 Wiley Periodicals, Inc. 相似文献
10.
Rajkumar Dorajoo Ruoying Li Mohammad Kamran Ikram Jianjun Liu Philippe Froguel Jeannette Lee Xueling Sim Rick Twee-Hee Ong Wan Ting Tay Chen Peng Terri L. Young Alexandra I. F. Blakemore Ching Yu Cheng Tin Aung Paul Mitchell Jie Jin Wang Caroline C. Klaver Eric Boerwinkle Ronald Klein David S. Siscovick Richard A. Jensen Vilmundur Gudnason Albert Vernon Smith Yik Ying Teo Tien Yin Wong E-Shyong Tai Chew-Kiat Heng Yechiel Friedlander 《PloS one》2013,8(7)