US3627638A
Expired / Lapsed
US
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Amylase chemically coupled to cellulose ethers
Assignee: RANKS HORIS MCDOUGALL Ltd
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Filing: 1969-10-16
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Granted: 1971-12-14
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Expires: 1989-10-16
Abstract
Abstract A water insoluble amylase comprising Alpha - Beta - or gamma -amylase chemically coupled to p-diazophenoxy hydroxypropyl cellulose or Alpha - or Beta - amylase chemically coupled to pisothiocyanatophenoxy hydroxypropyl cellulose. These are prepared by dissolving Alpha -, Beta - or gamma -amylase in a buffer within a pH range of 6.3-7.7 and reacting at 0*-5* C. with the pdiazophenoxy hydroxypropyl ether of cellulose or by dissolving Alpha - or Beta -amylase in a buffer at a pH of approximately 8.6 with a p-isothiocyanato phenoxy hydroxypropyl ether of cellulose.
Inventors
- 👤 Sidney Alan Barker
- 👤 Peter John Somers
- 👤 Roger Epton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:39
CPC Classifications
C; C12; C12N; C12N11/00; C12N11/02; C12N11/10; C12N11/12
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
16 words
A process as claimed in claim 1 wherein the pH range is between 7.6 and 7.7.
Claim 2
Dependent Claim
24 words
A process as claimed in claim 2 wherein unreacted diazo groups in the cellulose derivative are annealed by reaction with Beta -naphthol or phenol.
Claim 3
Dependent Claim
31 words
A process as claimed in claim 2 wherein the degree of substitution of ether groups in the cellulose is between 13.-56.2 microequivalents of p-diazophenoxy hydroxypropyl etheR groups per gram of cellulose.
Claim 4
Dependent Claim
39 words
A process for the preparation of an active water insoluble amylase which process comprises reacting at 0*-5* C., Alpha or Beta -amylase dissolved in a buffer at a pH of approximately 8.6 with the P-isothiocyanato-phenoxy-hydroxypropyl ether of microcrystalline cellulose.
Claim 5
Dependent Claim
17 words
A process as claimed in claim 5 wherein the buffer is 0.05 M borate buffer, pH 8.6.
Claim 6
Dependent Claim
29 words
A process as claimed in claim 5 wherein the degree of substitution of ether groups in the cellulose is 13-56.2 microequivalents of p-isothiocyanato-phenoxy-hydroxypropyl ether groups per gram of cellulose.
Claim 7
Dependent Claim
35 words
A process as claimed in claim 1 wherein the p-diazophenoxy-hydroxypropyl ether of cellulose is prepared from 3-(p-aminophenoxy)-2-hydroxypropyl ether hydrochloride of cellulose by treatment with acidified sodium nitrite solution just prior to use for this purpose.
Claim 8
Dependent Claim
31 words
A process as claimed in claim 8 wherein the 3-(p-aminophenoxy)-2-hydroxypropyl ether hydrochloride of cellulose is prepared by reducing 2-hydroxy-3-(p-nitrophenoxy) propyl ether of cellulose using titanous chloride in the presence of acid.
Claim 9
Dependent Claim
18 words
A process as claimed in claim 9 wherein a citrate buffer is employed in place of the acid.
Claim 10
Dependent Claim
31 words
A process as claimed in claim 9 wherein the 2-hydroxy-3-(p-nitrophenoxy) propyl ether of cellulose is prepared by reaction of cellulose with glycidyl p-nitrophenyl ether under nitrogen in the presence of alkali.
Claim 11
Dependent Claim
28 words
A process as claimed in claim 9 wherein the 3-(p-aminophenoxy)-2-hydroxypropyl ether of cellulose is converted to 2-hydroxy-3-(p-isothiocyanatophenoxy) propyl ether of cellulose by treatment with thiophosgene in carbon tetrachloride.
Claim 12
Dependent Claim
8 words
Alpha -Amylase chemically coupled to p-diazophenoxy hydroxypropyl cellulose.
Claim 13
Dependent Claim
8 words
Beta -Amylase chemically coupled to p-diazophenoxy hydroxypropyl cellulose.
Claim 14
Dependent Claim
8 words
gamma -Amylase chemically coupled to p-diazophenoxy hydroxypropyl cellulose.
Claim 15
Dependent Claim
9 words
Alpha -Amylase chemically coupled to p-isothiocyanato phenoxy hydroxypropyl cellulose.
Claim 16
Dependent Claim
9 words
Beta -Amylase chemically coupled to p-isothiocyanato phenoxy hydroxypropyl cellulose.
Claim 17
Dependent Claim
30 words
A water insoluble amylase comprising Alpha - Beta - or gamma -amylase chemically coupled to p-diazophenoxy hydroxypropyl cellulose or Alpha - or Beta -amylase chemically coupled to p-isothiocyanatophenoxy hydroxypropyl cellulose.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-12-13 | 1975-06-14 | 1975-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-13 | 1979-06-14 | 1979-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-13 | 1983-06-14 | 1983-12-14 | $7700.00 | Window Closed / Lapsed |