Method for preparing an antitumor dextran using a dextran synthetase from Lactobacillus confusus
First Claim
1. A method for preparing an antitumor dextran which comprises(a) contacting sucrose with an antitumor dextran synthetase isolated from a culture broth produced by culturing a microorganism belonging to Lactobacillus confusus selected from the group consisting of 40-1 strain (FERM BP-2865), 40-3 strain (FERM BP-2866), 77-1 strain (FERM BP-2867), 78-1 strain (FERM BP-2868), 80-1 strain (FERM BP-2869) and mutants thereof which produce said antitumor dextran, whereby said dextran is produced, said dextran having the following properties:
- (1) Form;
said dextran is a white powder having no taste and no smell;
(2) Solubility;
said dextran is soluble in water, formamide and dimethylsulfoxide, but insoluble in alcohols, acetone, hexane, chloroform and carbon tetrachloride;
(3) pH of Aqueous Solution;
the aqueous solution is neutral or weakly acidic;
(4) Constituent Saccharide;
said dextran is comprised solely of glucose;
(5) Elementary analysis values;
said dextran comprises 43 to 45% of C and 6.0 to 6.3% of H;
(6) Structure;
said dextran is an α
-glucan comprised mainly of linear α
-1,6 glucoside linkages;
(7) Proteins;
said dextran contains no protein as determined by the Lowry'"'"'s method;
(8) Molecular weight;
said dextran does not permeate through a dialysis membrane and has a molecular weight which is higher than 10,000 daltons;
(9) Color Reaction;
said dextran is positive to anthrone sulfuric acid reaction and phenol sulfuric acid reaction, but negative to biuret reaction, the Lowry-Folin reaction, the Elson-Morgan reaction and the idione reaction;
(10) Melting Point;
said dextran has no definite melting point;
(11) Ultraviolet Absorption Spectrum;
said dextran has no characteristic ultraviolet absorption;
(12) Infrared Absorption Spectrum;
said dextran shows a characteristic absorption of α
-glucan;
(13) 13 C-NMR Spectrum;
said dextran shows a characteristic spectrum of α
-1,6-glucan;
(14) said dextran possesses antitumor activities, and(b) collecting said dextran from the culture broth.
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Abstract
A method is provided for preparing an antitumor dextran by contacting a culture broth containing sucrose with an antitumor dextran obtained from Lactobacillus confusus and collecting the antitumor dextran from the culture broth. The enzyme can be used as a crude enzyme solution or may be further purified by conventional means. The Lactobacillus confusus is preferably one of the following: 40-1 strain (FERM BP-2865) , 40-3 strain (FERM BP-2866) , 77-1 strain (FERM BP-2867), 78-1 strain (FERM BP-2868) or 80-1 strain (FERM BP-2869).
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Citations
18 Claims
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1. A method for preparing an antitumor dextran which comprises
(a) contacting sucrose with an antitumor dextran synthetase isolated from a culture broth produced by culturing a microorganism belonging to Lactobacillus confusus selected from the group consisting of 40-1 strain (FERM BP-2865), 40-3 strain (FERM BP-2866), 77-1 strain (FERM BP-2867), 78-1 strain (FERM BP-2868), 80-1 strain (FERM BP-2869) and mutants thereof which produce said antitumor dextran, whereby said dextran is produced, said dextran having the following properties: -
(1) Form;
said dextran is a white powder having no taste and no smell;(2) Solubility;
said dextran is soluble in water, formamide and dimethylsulfoxide, but insoluble in alcohols, acetone, hexane, chloroform and carbon tetrachloride;(3) pH of Aqueous Solution;
the aqueous solution is neutral or weakly acidic;(4) Constituent Saccharide;
said dextran is comprised solely of glucose;(5) Elementary analysis values;
said dextran comprises 43 to 45% of C and 6.0 to 6.3% of H;(6) Structure;
said dextran is an α
-glucan comprised mainly of linear α
-1,6 glucoside linkages;(7) Proteins;
said dextran contains no protein as determined by the Lowry'"'"'s method;(8) Molecular weight;
said dextran does not permeate through a dialysis membrane and has a molecular weight which is higher than 10,000 daltons;(9) Color Reaction;
said dextran is positive to anthrone sulfuric acid reaction and phenol sulfuric acid reaction, but negative to biuret reaction, the Lowry-Folin reaction, the Elson-Morgan reaction and the idione reaction;(10) Melting Point;
said dextran has no definite melting point;(11) Ultraviolet Absorption Spectrum;
said dextran has no characteristic ultraviolet absorption;(12) Infrared Absorption Spectrum;
said dextran shows a characteristic absorption of α
-glucan;(13) 13 C-NMR Spectrum;
said dextran shows a characteristic spectrum of α
-1,6-glucan;(14) said dextran possesses antitumor activities, and (b) collecting said dextran from the culture broth. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
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Specification