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US3627638A Expired / Lapsed US ⏱️ 0.0 years remaining

Amylase chemically coupled to cellulose ethers

Assignee: RANKS HORIS MCDOUGALL Ltd
•
Filing: 1969-10-16
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Granted: 1971-12-14
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Expires: 1989-10-16
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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

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