Claims
- 1. A process for producing a polysaccharide RON substance which comprises
- (a) contacting sucrose with a polysaccharide RON substance synthetase derived from a microorganism having a capacity of producing the polysaccharide RON substance, the microorganism belonging to the genus Leuconostoc and being at least one strain of Leuconostoc mesenteroides subsp. dextranicum, said strain selected from the group consisting of strain BL-75 (FERM BP-2242), strain NCFB 517 (FERM BP-2711), strain NCFB 531 (FERM BP-2712), strain NCFB 861 (FERM BP-2713), strain NCBF 864 (FERM BP-2714), strain 46-1 (FERM BP-2670), and mutants thereof, to form the polysaccharide RON substance having the following properties:
- (1) form: the substance is a white amorphous powder;
- (2) solubility: the substance is soluble in water, but the solution becomes milky white and viscous when the concentration is elevated; the substance is soluble in formamide and dimethylsulfoxide, but the substance is insoluble in alcohols, acetone, benzene, ethyl acetate, hexane, chloroform and carbon tetrachloride;
- (3) pH of aqueous solution: the aqueous solution is neutral or weakly acidic;
- (4) constituent saccharide: the substance comprises solely glucose;
- (5) elementary analysis values: the substance comprises 44.0 to 45.0% C and 6.1 to 6.3% of H;
- (6) structure: the substance is an .alpha.-1,6-glucan and comprises a small amount of 3,6-branched side chains;
- (7) proteins: the substance contains almost no proteins;
- (8) molecular weight: the substance does not permeate through a dialysis membrane and the molecular weight is considered to be higher than 10,000 daltons;
- (9) specific rotation: formamide);
- (10) color reaction: the substance is positive to an anthrone sulfuric acid reaction and a phenol sulfuric acid reaction, but negative to a biurette reaction, the Lowry-Folin reaction, the Elson-Morgan reaction and an iodine reaction;
- (11) ultraviolet absorption spectrum: the substance has no characteristic absorption;
- (12) infrared absorption spectrum: the substance shows a characteristic absorption of .alpha.-glucan;
- (13) .sup.13 C-NMR spectrum: the substance shows an absorption having characteristic chemical shift values of .alpha.-1, 6-glucan in the main signals; and
- (14) biological activity: the substance has an antitumor activity against a transplantable tumor in mice, said transplantable tumor being syngeneic tumor Meth A;
- and (b) collecting said substance.
- 2. The process for producing the polysaccharide RON substance according to claim 1, wherein the microorganism having a capacity of producing the polysaccharide RON substance is Leuconostoc mesenteroides subsp. dextranicum, strain BL-75 (FERM BP-2242) or strain 46-1 (FERM BP-2670).
- 3. The process for producing the polysaccharide RON substance according to claim 1, wherein the sucrose is in a form of white refined sugar, molasses or reagent grade sucrose.
- 4. The process for producing the polysaccharide RON substance according to claim 3, wherein the synthetase is in a concentration of 0.2 to 2 U/ml.
- 5. The process for producing the polysaccharide RON substance according to claim 3, wherein the synthetase is in a concentration of 0.5 to 1 U/ml.
- 6. The process for producing the polysaccharide RON substance according to claim 5, wherein the sucrose is in a concentration of 5 to 30%.
- 7. A process for producing a polysaccharide RON substance which comprises
- (a) contacting sucrose with a polysaccharide RON substance synthetase to form the polysaccharide RON substance having the following properties:
- (1) form: the substance is a white amorphous powder;
- (2) solubility: the substance is soluble in water, the substance is soluble in formamide and dimethylsulfoxide, but the substance is insoluble in alcohols, acetone, benzene, ethyl acetate, hexane, chloroform and carbon tetrachloride;
- (3) pH of aqueous solution: the aqueous solution is neutral or weakly acidic;
- (4) constituent saccharide: the substance comprises solely glucose;
- (5) elementary analysis values: the substance comprises 44.0 to 45.0% of C and 6.1 to 6.3% of H;
- (6) structure: the substance is an .alpha.-1,6-glucan and comprises a small amount of 3,6-branched side chains;
- (7) proteins: the substance comprises almost no proteins;
- (8) molecular weight: the substance does not permeate through a dialysis membrane and the molecular weight is considered to be higher than 10,000 daltons;
- (9) specific rotation: (.alpha.).sub.D.sup.25 =+190.degree..about.+220.degree. (C=0.5, formamide);
- (10) color reaction: the substance is positive to an anthrone sulfuric acid reaction and a phenol sulfuric acid reaction, but negative to a biurette reaction, the Lowry-Folin reaction, the Elson-Morgan reaction and an iodine reaction;
- (11) ultraviolet absorption spectrum: the substance has no characteristic absorption;
- (12) infrared absorption spectrum: the substance shows a characteristic absorption of .alpha.-glucan;
- (13) .sup.13 C-NMR spectrum: the substance shows an absorption characteristic of chemical shift values of .alpha.-1,6-glucan in the main signals; and
- (14) biological activity: the substance has an antitumor activity against a transplantable tumor in mice, said tumor being syngeneic tumor Meth A;
- and (b) collecting said substance.
- 8. The process for producing a polysaccharide RON substance according to claim 10, wherein the RON substance synthetase is a polysaccharide RON substance synthetase having the following properties:
- (a) action: the enzyme decomposes 1 mol of sucrose to form 1 mol of fructose, and simultaneously, the enzyme transfers the glucose portion to the polysaccharide RON substance acting as the receptor;
- (b) optimum pH: the optimum pH value is about 5.5;
- (c) stable pH range: the enzyme is stable in the pH range of from 4.5 to 7.0;
- (d) substrate specificity: formation of the biologically active polysaccharide RON substance from glucose, fructose, maltose and isomaltose is not observed, but the enzyme reacts only with sucrose to form the biologically active polysaccharide RON substance;
- (e) optimum temperature: the optimum temperature is about 40.degree. C.; and
- (f) stable temperature range: the enzyme is stable at a temperature lower than 40.degree. C.
Priority Claims (1)
Number |
Date |
Country |
Kind |
1-29382 |
Feb 1989 |
JPX |
|
Parent Case Info
This application is a continuation of application Ser. No. 07/912,128 filed Jul. 9, 1992, (abandoned), which is a continuation of application Ser. No. 07/807,969 filed Dec. 11, 1991 (abandoned), which is a continuation of application Ser. No. 07/467,857 filed Jan. 22, 1990 (abandoned).
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
4762825 |
Takeo et al. |
Aug 1988 |
|
Foreign Referenced Citations (3)
Number |
Date |
Country |
0087404 |
Feb 1983 |
EPX |
0172559 |
Aug 1985 |
EPX |
3224547 |
Jan 1984 |
DEX |
Non-Patent Literature Citations (3)
Entry |
Chemical Abstracts, vol. 110, No. 1, Jan. 2, 1989, Columbus, Ohio, USA, Takeo Suguru et al., "Studies on an Antitumor Polysaccharide RBS Derived from Rice Bran. II. Preparation and General Properties of RON, an Active Fraction of RBS." p. 392, abstract No. 387w & Chem. Pharm. Bull. 1988, 36(9), 3609-13. |
Marina E. Preobrazhenskaya et al, Studies on Some Biologically Active Dextrans, Carbohydrate Research, 66 (1978) pp. 213-223. |
S. M. Navashin et al, Antitumor and Antibacterial Activity of Dextran LU-122 and Its Effect on Macrophage Activity, Curr. Chemother. Immunother., Proc. Int. Congr. Chemther, 12th, 1, pp. 190-192 (1982). |
Continuations (3)
|
Number |
Date |
Country |
Parent |
912128 |
Jul 1992 |
|
Parent |
807969 |
Dec 1991 |
|
Parent |
467857 |
Jan 1990 |
|