Abstract
Eight varieties of lettuce (Lactuca sativum) and three varieties of endive (Cichorium endivia) were analyzed for flavonoid composition and content. Total flavonoid contents, expressed as units of aglycon for fresh material, were in the ranges of 0.3-229 microg/g for lettuce and 44-248 microg/g for endive. Five quercetin conjugates [quercetin 3-O-galactoside, quercetin 3-O-glucoside, quercetin 3-O-glucuronide, quercetin 3-O-(6-O-malonyl)glucoside, and quercetin 3-O-rhamnoside] and luteolin 7-O-glucuronide were measured in the green-leafed lettuce and an additional two cyanidin conjugates [cyanidin 3-O-glucoside and cyanidin 3-O-[(6-O-malonyl)glucoside]] in the red-leafed varieties. Three kaempferol conjugates [kaempferol 3-O-glucoside, kaempferol 3-O-glucuronide, and kaempferol 3-O-[6-O-malonyl)glucoside]] were measured in each of the endive varieties. The presence and identity of kaempferol 3-O-(6-O-malonyl)glucoside in endive was shown for the first time. Shredding of lettuce leaf followed by exposure to light produced significant losses of the flavonoid moiety in the green oak leaf (94%), red oak leaf (43%), iceberg (36%), green batavia (25%), lollo biondo (24%), and lollo rosso (6%) samples, whereas cos and green salad bowl samples did not show an overall loss. Shredding of endive also produced loss of the flavonoid moiety in escarole (32%), fine frisee (13%), and coarse frisee (8%). Significant demalonation was observed for both the quercetin and cyanidin glucosides in lettuce, whereas a similar degradation of the kaempferol analogue was found in endive tissue. Storage of whole heads of both lettuce and endive in the dark at 1 degrees C and 98% humidity for 7 days resulted in losses of total flavonol glycosides in the range of 7-46%. The identification of the amounts, position of substitution, and nature of the sugars is important for understanding the potential bioavailability and biological activities of flavonoids in salads.
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Claims 19
Claim · model-written summary
Lettuce total flavonoids ranged from 0.3 to 229 microg/g.
- Taxon
- lettuce
Lactuca sativae0 - Outcome
- Total flavonoid contentse0
- Value
- 0.3-229 microg/ge0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Total flavonoid contents, expressed as units of aglycon for fresh material, were in the ranges of 0.3-229 microg/g for lettuce and 44-248 microg/g for endive”
Claim · model-written summary
Endive total flavonoids ranged from 44 to 248 microg/g.
- Taxon
- endive
Cichorium endiviae0 - Outcome
- Total flavonoid contentse0
- Value
- 44-248 microg/ge0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.jpg?width=500)
Verbatim
e0“Total flavonoid contents, expressed as units of aglycon for fresh material, were in the ranges of 0.3-229 microg/g for lettuce and 44-248 microg/g for endive”
Claim · model-written summary
Green-leafed lettuce contained five quercetin conjugates and luteolin 7-O-glucuronide.
- Taxon
- lettuce
Lactuca sativae0 - Material
- green-leafed lettucee0
- Outcome
- quercetin conjugatese0
- Value
- Fivee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Five quercetin conjugates [quercetin 3-O-galactoside, quercetin 3-O-glucoside, quercetin 3-O-glucuronide, quercetin 3-O-(6-O-malonyl)glucoside, and quercetin 3-O-rhamnoside] and luteolin 7-O-glucuronide were measured in the green-leafed lettuce”
Claim · model-written summary
Red-leafed lettuce also contained two cyanidin conjugates.
- Taxon
- lettuce
Lactuca sativat0 - Material
- red-leafed varietiese0
- Outcome
- cyanidin conjugatese0
- Value
- twoe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“an additional two cyanidin conjugates [cyanidin 3-O-glucoside and cyanidin 3-O-[(6-O-malonyl)glucoside]] in the red-leafed varieties”
t0“Lettuce”
Claim · model-written summary
Endive varieties contained three kaempferol conjugates.
- Taxon
- endive
Cichorium endiviae0 - Outcome
- kaempferol conjugatese0
- Value
- Threee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.jpg?width=500)
Verbatim
e0“Three kaempferol conjugates [kaempferol 3-O-glucoside, kaempferol 3-O-glucuronide, and kaempferol 3-O-[6-O-malonyl)glucoside]] were measured in each of the endive varieties”
Claim · model-written summary
Kaempferol 3-O-(6-O-malonyl)glucoside was identified in endive for the first time.
- Taxon
- endive
Cichorium endiviae0 - Outcome
- presence and identity of kaempferol 3-O-(6-O-malonyl)glucosidee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.jpg?width=500)
Verbatim
e0“The presence and identity of kaempferol 3-O-(6-O-malonyl)glucoside in endive was shown for the first time”
Claim · model-written summary
Shredding and light exposure reduced green oak leaf lettuce flavonoids by 94%.
- Taxon
- lettuce
Lactuca sativae0 - Material
- green oak leafe0
- Treatment
- Shredding of lettuce leaf followed by exposure to lighte0
- Outcome
- flavonoid moietye0
- Direction
- lossese0
- Value
- 94%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Shredding of lettuce leaf followed by exposure to light produced significant losses of the flavonoid moiety in the green oak leaf (94%), red oak leaf (43%), iceberg (36%), green batavia (25%), lollo biondo (24%), and lollo rosso (6%) samples”
Claim · model-written summary
Shredding and light exposure reduced red oak leaf lettuce flavonoids by 43%.
- Taxon
- lettuce
Lactuca sativae0 - Material
- red oak leafe0
- Treatment
- Shredding of lettuce leaf followed by exposure to lighte0
- Outcome
- flavonoid moietye0
- Direction
- lossese0
- Value
- 43%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Shredding of lettuce leaf followed by exposure to light produced significant losses of the flavonoid moiety in the green oak leaf (94%), red oak leaf (43%), iceberg (36%), green batavia (25%), lollo biondo (24%), and lollo rosso (6%) samples”
Claim · model-written summary
Shredding and light exposure reduced iceberg lettuce flavonoids by 36%.
- Taxon
- lettuce
Lactuca sativae0 - Material
- iceberge0
- Treatment
- Shredding of lettuce leaf followed by exposure to lighte0
- Outcome
- flavonoid moietye0
- Direction
- lossese0
- Value
- 36%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Shredding of lettuce leaf followed by exposure to light produced significant losses of the flavonoid moiety in the green oak leaf (94%), red oak leaf (43%), iceberg (36%), green batavia (25%), lollo biondo (24%), and lollo rosso (6%) samples”
Claim · model-written summary
Shredding and light exposure reduced green batavia lettuce flavonoids by 25%.
- Taxon
- lettuce
Lactuca sativae0 - Material
- green bataviae0
- Treatment
- Shredding of lettuce leaf followed by exposure to lighte0
- Outcome
- flavonoid moietye0
- Direction
- lossese0
- Value
- 25%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Shredding of lettuce leaf followed by exposure to light produced significant losses of the flavonoid moiety in the green oak leaf (94%), red oak leaf (43%), iceberg (36%), green batavia (25%), lollo biondo (24%), and lollo rosso (6%) samples”
Claim · model-written summary
Shredding and light exposure reduced lollo biondo lettuce flavonoids by 24%.
- Taxon
- lettuce
Lactuca sativae0 - Material
- lollo biondoe0
- Treatment
- Shredding of lettuce leaf followed by exposure to lighte0
- Outcome
- flavonoid moietye0
- Direction
- lossese0
- Value
- 24%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Shredding of lettuce leaf followed by exposure to light produced significant losses of the flavonoid moiety in the green oak leaf (94%), red oak leaf (43%), iceberg (36%), green batavia (25%), lollo biondo (24%), and lollo rosso (6%) samples”
Claim · model-written summary
Shredding and light exposure reduced lollo rosso lettuce flavonoids by 6%.
- Taxon
- lettuce
Lactuca sativae0 - Material
- lollo rossoe0
- Treatment
- Shredding of lettuce leaf followed by exposure to lighte0
- Outcome
- flavonoid moietye0
- Direction
- lossese0
- Value
- 6%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Shredding of lettuce leaf followed by exposure to light produced significant losses of the flavonoid moiety in the green oak leaf (94%), red oak leaf (43%), iceberg (36%), green batavia (25%), lollo biondo (24%), and lollo rosso (6%) samples”
Claim · model-written summary
Cos and green salad bowl lettuce did not show overall flavonoid loss after shredding and light exposure.
- Taxon
- Lettuce
Lactuca sativat0 - Material
- cos and green salad bowle0
- Outcome
- overall losse0
- Direction
- did not showe0
Not reportedTreatmentComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“cos and green salad bowl samples did not show an overall loss”
t0“Lettuce”
Claim · model-written summary
Shredding reduced escarole endive flavonoids by 32%.
- Taxon
- endive
Cichorium endiviae0 - Material
- escarolee0
- Treatment
- Shredding of endivee0
- Outcome
- flavonoid moietye0
- Direction
- losse0
- Value
- 32%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.jpg?width=500)
Verbatim
e0“Shredding of endive also produced loss of the flavonoid moiety in escarole (32%), fine frisee (13%), and coarse frisee (8%)”
Claim · model-written summary
Shredding reduced fine frisee endive flavonoids by 13%.
- Taxon
- endive
Cichorium endiviae0 - Material
- fine friseee0
- Treatment
- Shredding of endivee0
- Outcome
- flavonoid moietye0
- Direction
- losse0
- Value
- 13%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.jpg?width=500)
Verbatim
e0“Shredding of endive also produced loss of the flavonoid moiety in escarole (32%), fine frisee (13%), and coarse frisee (8%)”
Claim · model-written summary
Shredding reduced coarse frisee endive flavonoids by 8%.
- Taxon
- endive
Cichorium endiviae0 - Material
- coarse friseee0
- Treatment
- Shredding of endivee0
- Outcome
- flavonoid moietye0
- Direction
- losse0
- Value
- 8%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.jpg?width=500)
Verbatim
e0“Shredding of endive also produced loss of the flavonoid moiety in escarole (32%), fine frisee (13%), and coarse frisee (8%)”
Claim · model-written summary
Lettuce quercetin and cyanidin glucosides showed significant demalonation.
- Taxon
- lettuce
Lactuca sativae0 - Outcome
- demalonatione0
- Qualifier
- quercetin and cyanidin glucosidese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Significant demalonation was observed for both the quercetin and cyanidin glucosides in lettuce”
Claim · model-written summary
The kaempferol analogue degraded in endive tissue.
- Taxon
- endive
Cichorium endiviae0 - Organ / stage
- endive tissuee0
- Outcome
- degradation of the kaempferol analoguee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.jpg?width=500)
Verbatim
e0“a similar degradation of the kaempferol analogue was found in endive tissue”
Claim · model-written summary
Dark storage of whole lettuce and endive heads at 1 degrees C and 98% humidity for 7 days caused 7–46% total flavonol glycoside loss.
- Taxon
- lettuce and endive
Lactuca sativa
Cichorium endiviae0 - Organ / stage
- whole headse0
- Treatment
- Storage of whole heads of both lettuce and endive in the dark at 1 degrees C and 98% humidity for 7 dayse0
- Outcome
- total flavonol glycosidese0
- Direction
- lossese0
- Value
- 7-46%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

.jpg?width=500)
Verbatim
e0“Storage of whole heads of both lettuce and endive in the dark at 1 degrees C and 98% humidity for 7 days resulted in losses of total flavonol glycosides in the range of 7-46%”
The same questions in other papers
storage · molecular: metabolites · Cichorium endivia (endive)Positive and negative results
1 in the opposite direction
- positive
storage · molecular: metabolites · Lactuca sativa (garden lettuce)Positive and negative results
3 papers in the same direction as this paper · 5 in the opposite direction
- positive
- positive
- positive
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See all 9 papers →light · quality: phytochemicals · Lactuca sativa (garden lettuce)Positive and negative results
7 papers in the same direction as this paper · 43 in the opposite direction
- positive
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See all 51 papers →light · molecular: metabolites · Lactuca sativa (garden lettuce)Positive and negative results
9 papers in the same direction as this paper · 42 in the opposite direction
- positive
- positive
- positive
48 papers more in this group
See all 52 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.