US3879890A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Algal polysaccharide production
Assignee: National Research Council Canada
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Filing: 1974-02-06
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Granted: 1975-04-29
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Expires: 1994-02-06
Abstract
Abstract Selected polysaccharides are produced from algal plant tissue by (a) separating vegetative parts or spores into (i) gametophytes, or (ii) tetrasporophytes; (b) vegetatively propagating the separated plant material; (c) harvesting the resulting plant growth; and (d) recovering the desired polysaccharides from the harvested material. Different specific polysaccharides (e.g., kappa- or lambda-carrageenan) have been found to be produced by (i) or (ii) above. This method avoids difficult post-harvest separations and is amenable to controlled vegetative propagation of the separated plant material under optimum conditions.
Inventors
- 👤 Lawrence C M Chen
- 👤 James S Craigie
- 👤 Esther L Mccandless
- 👤 Jack L Mclachlan
- 👤 Arthur C Neish
- 👤 Peter F Shacklock
- 👤 John A Walter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:24
CPC Classifications
A; A01; A01G; A01G33/00; C; C08; C08B; C08B37/00; C08B37/0006; C08B37/0036; C08B37/0042; Y; Y02; Y02A; Y02A40/00; Y02A40/80
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
52 words
A METHOD FOR THE PRODUCTION OF SPECIFIC POLYSACCHARIDE FROM SELECTED ALGAL SPECIES PRODUCING THE DESIRED POLYSACCHARIDE, COMPRISING: A. PROVIDING VEGATATIVE PARTS OR SPORES SEPARATED INTO I. GAMETOPHYTES, OR II. TETRASPOROPHYTES, B. VEGETATIVELY PROPAGATING THE SEGREGATED PLANT MATERIAL, C. HARVESTING THE PLANT GROWTH, AND D. RECOVERING THE DESIRED POLYSACCHARIDES FROM THE HARVESTED PLANTS.
Claim 2
Independent Claim
52 words
A METHOD FOR THE PRODUCTION OF SPECIFIC POLYSACCHARIDE FROM SELECTED ALGAL SPECIES PRODUCING THE DESIRED POLYSACCHARIDE, COMPRISING: A. PROVIDING VEGATATIVE PARTS OR SPORES SEPARATED INTO I. GAMETOPHYTES, OR II. TETRASPOROPHYTES, B. VEGETATIVELY PROPAGATING THE SEGREGATED PLANT MATERIAL, C. HARVESTING THE PLANT GROWTH, AND D. RECOVERING THE DESIRED POLYSACCHARIDES FROM THE HARVESTED PLANTS.
Claim 3
Dependent Claim
21 words
The method of claim 1 wherein the polysaccharides are carrageenans and the algal strains are marine algae known to produce carrageenans.
Claim 4
Dependent Claim
19 words
The method of claim 2 wherein the strains are selected from species of the following genera: Chondrus, and Gigartina.
Claim 5
Dependent Claim
14 words
The method of claim 3 wherein the species are Chondrus crispus or Gigartina stellata.
Claim 6
Dependent Claim
15 words
The method of claim 2 wherein gametophytes are vegetatively propagated and kappa -carrageenan is recovered.
Claim 7
Dependent Claim
16 words
The method of claim 2 wherein tetrasporic algae are vegetatively propagated and lambda -carrageenan is recovered.
Claim 8
Dependent Claim
67 words
The method of claim 1 wherein the vegetative propagation is carried out by: i. providing seawater at a temperature suitable for the growth of the algae, as growth medium, ii. maintaining the pH in said seawater between approximately pH 6.5 to 8.5 by CO2 addition, and iii. maintaining the presence of assimilable nitrogen-source material to permit vigorous vegetative growth in the seawater system until shortly before harvesting.
Claim 9
Dependent Claim
27 words
The method of claim 7 wherein during a short period before harvesting no additional N-source material is supplied and the plant material is subject to strong illumination.
Claim 10
Dependent Claim
15 words
The method of claim 7 wherein fresh seawater is regularly supplied to the growth medium.
Claim 11
Dependent Claim
41 words
The method of claim 7 wherein the concentration of nitrogen-source material is maintained by continuously or intermittently supplying fixed nitrogen during the vigorous growth stage and then is allowed to become substantially exhausted for approximately 2 - 3 weeks before harvest.
Claim 12
Dependent Claim
32 words
The method of claim 10 wherein during said 2 - 3 week period the plants are subject to strong illumination sufficient to substantially decolorize the alga resulting in an improved polysaccharide material.
Claim 13
Dependent Claim
28 words
The method of claim 1 wherein different types of polysaccharides are recovered from (i) and (ii) in separate growth areas and blended to produce a desired polysaccharide mixture.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-28 | 1978-10-28 | 1979-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-28 | 1982-10-28 | 1983-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-28 | 1986-10-28 | 1987-04-29 | $7700.00 | Window Closed / Lapsed |