Abstract
Five years ago it was unequivocally demonstrated for the first time that an isolated plant organ, the root, could be grown in culture for potentially unlimited periods of time (8). An environmental complex capable of supporting normal growth for such periods was outlined which included only one factor recognized as being of unknown constitution. That factor was an extract of dried brewers' yeast representing 1/10,000 of the total mass of the nutrient. Since this one unknown made interpretations of any experiments utilizing the complex of uncertain validity, much effort has been expended since then aiming at the elimination of this factor. Analysis showed the effective material to be soluble in 85 per cent, alcohol, insoluble in ether, and separable by extraction with 100 per cent, alcohol into two fractions both of which were essential for normal growth (10). The fraction insoluble in 100 per cent, alcohol was shown to be replaceable by a mixture of 9 amino acids (11). This demonstration was obtained before the nature of the 100 per cent, alcohol soluble material, now known to be thiamin or its precursors, was known (1, 4,12). A nutrient containing thiamin and amino acids was still inferior to the original yeast extract medium. It was shown to be improved by addition of a complex mixture of accessory salts. Analysis of the accessory salt mixture showed most of the ingredients to be either inert or detrimental, and by elimination of all but four (iodine, manganese, zinc, and boron), the nutrient was improved to the point where growth equal to that in a yeast extract medium could be obtained (13). A completely known nutrient for the maintenance of normal growth of excised tomato roots was thus made available.
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Claims 8
Claim · model-written summary
The effective yeast-extract material was soluble in 85 per cent alcohol and insoluble in ether.
- Taxon
- TOMATO
Solanum lycopersicumt0 - Outcome
- effective material to be soluble in 85 per cent, alcohol, insoluble in ethere0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Analysis showed the effective material to be soluble in 85 per cent, alcohol, insoluble in ether”
t0“EXCISED TOMATO ROOTS”
Claim · model-written summary
Extraction with 100 per cent alcohol yielded two fractions essential for normal root growth.
- Taxon
- TOMATOSolanum lycopersicumt0
- Outcome
- two fractions both of which were essential for normal growthe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“separable by extraction with 100 per cent, alcohol into two fractions both of which were essential for normal growth”
t0“EXCISED TOMATO ROOTS”
Claim · model-written summary
Nine amino acids could replace the insoluble fraction.
- Taxon
- TOMATOSolanum lycopersicumt0
- Treatment
- mixture of 9 amino acidse0
- Outcome
- replaceablee0
- Comparator
- fraction insoluble in 100 per cent, alcohole0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The fraction insoluble in 100 per cent, alcohol was shown to be replaceable by a mixture of 9 amino acids”
t0“EXCISED TOMATO ROOTS”
Claim · model-written summary
Nutrient with thiamin and amino acids was inferior to yeast extract medium.
- Taxon
- TOMATOSolanum lycopersicumt0
- Treatment
- thiamin and amino acidse0
- Outcome
- inferiore0
- Direction
- inferiore0
- Comparator
- original yeast extract mediume0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“A nutrient containing thiamin and amino acids was still inferior to the original yeast extract medium.”
t0“EXCISED TOMATO ROOTS”
Claim · model-written summary
Accessory salts improved the defined nutrient.
- Taxon
- TOMATOSolanum lycopersicumt0
- Treatment
- addition of a complex mixture of accessory saltse0
- Outcome
- improvede0
- Direction
- improvede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“It was shown to be improved by addition of a complex mixture of accessory salts.”
t0“EXCISED TOMATO ROOTS”
Claim · model-written summary
Most accessory salt ingredients were inert or detrimental.
- Taxon
- TOMATOSolanum lycopersicumt0
- Outcome
- inert or detrimentale0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“most of the ingredients to be either inert or detrimental”
t0“EXCISED TOMATO ROOTS”
Claim · model-written summary
Retaining iodine, manganese, zinc and boron supported growth equal to yeast extract medium.
- Taxon
- TOMATOSolanum lycopersicumt0
- Treatment
- iodine, manganese, zinc, and borone0
- Outcome
- growthe0
- Direction
- equale0
- Comparator
- yeast extract mediume0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“by elimination of all but four (iodine, manganese, zinc, and boron), the nutrient was improved to the point where growth equal to that in a yeast extract medium could be obtained”
t0“EXCISED TOMATO ROOTS”
Claim · model-written summary
A completely known nutrient became available for normal excised tomato root growth.
- Taxon
- tomatoSolanum lycopersicume0
- Outcome
- maintenance of normal growth of excised tomato rootse0
Not reportedComparatorValue
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“A completely known nutrient for the maintenance of normal growth of excised tomato roots was thus made available.”
The same questions in other papers
boron atom · growth · Solanum lycopersicum (tomato)Results differ
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See all 5 papers →manganese atom · growth · Solanum lycopersicum (tomato)Positive and negative results
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- negative
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See all 9 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.