Large-scale isolation of fraction 1 leaf protein (18S) from lucerne (Medicago sativa L)

1976 ◽  
Vol 86 (3) ◽  
pp. 495-501 ◽  
Author(s):  
W. T. Jones ◽  
J. L. Mangan

SummaryFraction 1 protein (18S) can be isolated in large quantities (order 100 g) in a soluble state by heating lucerne juice, adjusted to pH 6·7 to 6·9, from a Pirie extractor to 63 °C for 10 min. Low speed oentrifugation (2500 g) removed coagulated chloroplast fragments and most of the heat-denatured Fraction 2 proteins. Fraction 1 (18S) protein (> 95% pure) was purified from low molecular weight materials (sugars, phenolics etc.) by ammonium sulphate fractionation and gel filtration on Sephadex G-75 gels.

1981 ◽  
Vol 46 (03) ◽  
pp. 612-616 ◽  
Author(s):  
U Schmitz-Huebner ◽  
L Balleisen ◽  
F Asbeck ◽  
J van de Loo

SummaryHigh and low molecular weight heparin fractions obtained by gel filtration chromatography of sodium mucosal heparin were injected subcutaneously into six healthy volunteers and compared with the unfractionated substance in a cross-over trial. Equal doses of 5,000 U were administered twice daily over a period of three days and heparin activity was repeatedly controlled before and 2, 4, 8 hrs after injection by means of the APTT, the anti-Xa clotting test and a chromogenic substrate assay. In addition, the in vivo effect of subcutaneously administered fractionated heparin on platelet function was examined on three of the volunteers. The results show that s.c. injections of the low molecular weight fraction induced markedly higher anti-Xa activity than injections of the other preparations. At the same time, APTT results did not significantly differ. Unfractionated heparin and the high molecular weight fraction enhanced ADP-induced platelet aggregation and collagen-mediated MDA production, while the low molecular weight fraction hardly affected these assays, but potently inhibited thrombin-induced MDA production. All heparin preparations stimulated the release of platelet Factor 4 in plasma. During the three-day treatment periods, no side-effects and no significant changes in the response to heparin injections were detected.


Author(s):  
Makoto Ogata

Abstract Carbohydrates play important and diverse roles in the fundamental processes of life. We have established a method for accurately and a large scale synthesis of functional carbohydrates with diverse properties using a unique enzymatic method. Furthermore, various artificial glycan-conjugated molecules have been developed by adding these synthetic carbohydrates to macromolecules and to middle and low molecular weight molecules with different properties. These glycan-conjugated molecules have biological activities comparable to or higher than those of natural compounds, and present unique functions. In this review, several synthetic glycan-conjugated molecules are taken as examples to show design, synthesis and function.


1966 ◽  
Vol 44 (5) ◽  
pp. 849-859 ◽  
Author(s):  
Sumner M. Robinson ◽  
David A. Hurwitz ◽  
Robert Louis-Ferdinand ◽  
William F. Blatt

A technique is described for hemodialysis of either anesthetized or non-restrained rats. In the apparatus the dialysis plates of an autoanalyzer system are used with only minor modification. The efficiency of this method has been evaluated with regard to the clearance of saccharides, both in vitro and in vivo, as well as the extraction of nitrogenous low molecular weight moieties from circulating blood. Approximately 50% of the dialyzable material was obtained in a 1-hour dialysis. Further fractionation of the dialyzate was accomplished by gel filtration (Sephadex G-25).


1981 ◽  
Vol 153 (4) ◽  
pp. 968-976 ◽  
Author(s):  
M W Russell ◽  
T A Brown ◽  
J Mestecky

The IgA mediated hepatobiliary excretion of antigen from the circulation was studied using a radiolabeled haptenated protein (dinitrophenyl-human serum albumin) injected intravenously in mice together with monoclonal anti-dinitrophenyl antibodies of different immunoglobulin classes. Antibodies were obtained from ascitic fluids of mice bearing the MOPC315 myeloma (IgA), or immune spleen cell hybridomas (IgG and IgM). IgA antibody brought about the transport of large amounts of antigen from the circulation to the bile during 1-3h. Analysis of bile by gel filtration showed that a large part of the transported antigen remained intact and complexed with IgA. Neither IgA of different specificity nor anti-dinitrophenyl IgM medicated biliary transport of antigen. With anti-dinitrophenyl IgG, only small amounts of low molecular weight fragments of labeled antigen were found in he bile. Preformed immune complex of radiolabeled antigen and IgA antibody were rapidly transported from the circulation to the bile, resulting in threefold-higher levels of radioactivity in bile than in serum. It is proposed that an important function of serum IgA is to mediate the hepatobiliary excretion of corresponding circulating antigens.


1981 ◽  
Author(s):  
U Schmitz-Huebner ◽  
L Balleisen ◽  
F Asbeck ◽  
J van de Loo

Recent investigations suggest that low molecular weight heparin may have advantages over conventional heparin with regard to the prevention of venous thrombosis and haemorrhagic side effects.High (HMW) and low (LMW) molecular weight heparin fractions with mean MWs of 16,000 and 8,800 respectively, obtained by gel filtration chromatography of sodium mucosal heparin (B. Braun Melsungen), were injected subcutaneously into six volunteers and compared with the unfractionated substance in a cross-over trial. Doses of 5,000 U were administered twice daily over a period of three days and heparin activity was controlled before injection and 2,4,8 hours afterwards by means of the APTT, the anti-Xa clotting test and a chromogenic substrate assay. In addition, the in vivo effect of fractionated heparin on platelet function was examined. The results show that the LMW fraction induced markedly higher anti-Xa activity than the other preparations. At the same time, APTT results did not significantly differ. Unfractionated heparin and the HMW fraction enhanced ADP-induced platelet aggregation and collagen-mediated MDA-production, while the LMW fraction hardly affected these assays, but potently inhibited thrombin-induced MDA production. All heparin preparations stimulated the release of PF IV, whereas the serotonin content of platelets determined at the same time increased.It is concluded that s.c. injections of LMW heparin induce relatively high levels of anti-Xa activity without leading to sensitive platelet activation or to major effects on overall clotting tests.


1977 ◽  
Author(s):  
M. J. Seghatchian ◽  
T. Barrowcliffe ◽  
M. Miller-Andersson

Adsorption of plasma by A1(OH)3 is a requirement for the two stage assay of F VIII. It is generally accepted that factors II, VII, IX and X are removed by the procedure, while factors V and VIII are unaffected. Following gel filtration of a F VIII concentrat on Sepharose 4 B F VIII:c was found in the low molecular weight area, as well as in the void volume as expected. This activity was found with both one and two stage techniques. After adsorption of the fractions with Al(OH)3 to eliminate the non F VIII procoagulant activity F VIII:c disappeared from the void volume fractions and was much reduced in the low molecular region. F VIII: R Ag was also removed from these fractions by A1(OH)3 adsorption. After adsorption of fractions in the presence of hemophilia plasma clotting activity remained in both regions suggesting the presence of true F VIII activity. Thus at concentration of 1 IU of F VIII:c per ml, a low purity preparation was unaffected by A1(OH)3 adsorption whereas both antigen and clotting activity of a high purity concentrate were conciderably reduced. Addition of 5 % albumin to the high purity preparation prevented this adsorption. It is concluded that under conditions of high purification F VIII:c can be adsorbed preferentially on A1(OH)3 and this appears to be due to removal of F VIII:R Ag.


1975 ◽  
Vol 228 (4) ◽  
pp. 1020-1023 ◽  
Author(s):  
CJ Hahn ◽  
GW Evans

The effects of zinc deficiency on the whole-body absorption and intestinal content of Zn, Cd, Cu, Co, Fe, Mn, and Cr were determined in the rat 1 h after oral administration of the isotopes. Both the absorption and intestinal content of Zn and Cr were increased in zinc-deficient rats, and the intestinal content of Feand Co was also increased in the zinc-deficient animals. Zinc administered orally with Cr decreased both absorption and intestinal content of the isotope in zinc-deficient rats. Chromium administered orally with Zn decreased intestinal content and absorption of Zn in zinc-deficient rats. Fractionation of mucosal supernatants by gel filtration showed that both zinc and chromium eluted in the same low molecular weight fraction. The elution patterns of zinc and cadmium from that of zinc-supplemented animals. These experiments provide some insight into the specificity of the zinc absorption pathway and present some explanations for the interaction or lack of interaction among trace elements.


1973 ◽  
Vol 30 (10) ◽  
pp. 1525-1536 ◽  
Author(s):  
D. R. S. Lean

A model consistent with the kinetics of phosphorus in epilimnetic lake water was developed. Adding 32PO4 to lake water and separating the major forms of dissolved phosphorus by Sephadex gel filtration showed that the exchange mechanism between inorganic phosphate and the particulate fraction predominates. At the same time, a low-molecular-weight phosphorus compound is excreted which combines with colloids in lake water, releasing phosphate from the colloid and making the phosphate available for "transfer" again. This rapid cycling of phosphorus between the four principal forms — the particulate fraction, the low-molecular-weight P compound, colloidal P, and phosphate — appears to contribute to formation of colloids in lake water. No direct complexing of phosphate to the colloid was observed. Only in the presence of algae, bacteria, and other particulate matter did the radioactive phosphorus move to the low-molecular weight and the colloidal forms. The low-molecular-weight compound is negatively charged, as is the colloidal P, but to a lesser degree. Both are removed by anion exchange materials along with phosphate, but the rate that they move into the fraction removed by membrane filtration is different from that for phosphate. When filtrate is refiltered a large amount of the colloidal P is retained by the filter. This complicates measurements of transfer and makes previous studies on utilization of dissolved organic phosphorus of doubtful value since corrections for filter retention were rarely, if ever, made.


1965 ◽  
Vol 48 (3) ◽  
pp. 493-497
Author(s):  
E E Stinson ◽  
C O Willits

Abstract The colorants of pure maple, cane and maple, refined cane sugar, and light brown sugar sirups were separated into two fractions, one of high- and the other of lowmolecular weights, by means of gel filtration. The ratio of the amounts of high- to the low-molecular weight fractions of pure maple was the lowest of the four sirups and serves as a means of differentiation from these sirups. The color fraction ratio was highest for blended cane-maple sugar sirup. Many maple sirups are also distinguished by a pink band formed on the gel filtration column.


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