Abstract
Neem (Azadirachta indica) has been widely used as a traditional medicine and several bioactive compounds have been isolated from this species, but to date no potent allelopathic active substance has been reported. Therefore, we investigated possible allelopathic property and phytotoxic substances with allelopathic activity in neem. An aqueous methanol extract of neem leaves inhibited the growth of roots and shoots of cress, lettuce, alfalfa, timothy, crabgrass, ryegrass, barnyard grass and jungle rice. The extracts were then purified by several chromatographic runs while monitoring the inhibitory activity and two phytotoxic substances were isolated. The chemical structures of the two substances were determined by spectral data to correspond to novel compounds, nimbolide B (1) and nimbic acid B (2). Nimbolide B inhibited the growth of cress and barnyard grass at concentrations greater than 0.1‒3.0 μM. Nimbic acid B inhibited the growth of cress and barnyard grass at concentrations greater than 0.3-1.0 μM. These results suggest that nimbolide B and nimbic acid B may contribute to the allelopathic effects caused by neem leaves.
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Claims 15
Claim · model-written summary
Neem leaf extract inhibited root and shoot growth of cress.
- Taxon
- cresse0
- Treatment
- aqueous methanol extract of neem leavese0
- Interactor
- neem
.jpg?width=60)
Azadirachta indicae0other - Outcome
- growth of roots and shootse0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.jpg?width=500)
Verbatim
e0“An aqueous methanol extract of neem leaves inhibited the growth of roots and shoots of cress, lettuce, alfalfa, timothy, crabgrass, ryegrass, barnyard grass and jungle rice.”
Claim · model-written summary
Neem leaf extract inhibited root and shoot growth of lettuce.
- Taxon
- lettuce
Lactuca sativae0 - Treatment
- aqueous methanol extract of neem leavese0
- Interactor
- neemAzadirachta indicae0other
- Outcome
- growth of roots and shootse0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“An aqueous methanol extract of neem leaves inhibited the growth of roots and shoots of cress, lettuce, alfalfa, timothy, crabgrass, ryegrass, barnyard grass and jungle rice.”
Claim · model-written summary
Neem leaf extract inhibited root and shoot growth of alfalfa.
- Taxon
- alfalfa
Medicago sativae0 - Treatment
- aqueous methanol extract of neem leavese0
- Interactor
- neemAzadirachta indicae0other
- Outcome
- growth of roots and shootse0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“An aqueous methanol extract of neem leaves inhibited the growth of roots and shoots of cress, lettuce, alfalfa, timothy, crabgrass, ryegrass, barnyard grass and jungle rice.”
Claim · model-written summary
Neem leaf extract inhibited root and shoot growth of timothy.
- Taxon
- timothy
Phleum pratensee0 - Treatment
- aqueous methanol extract of neem leavese0
- Interactor
- neemAzadirachta indicae0other
- Outcome
- growth of roots and shootse0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“An aqueous methanol extract of neem leaves inhibited the growth of roots and shoots of cress, lettuce, alfalfa, timothy, crabgrass, ryegrass, barnyard grass and jungle rice.”
Claim · model-written summary
Neem leaf extract inhibited root and shoot growth of crabgrass.
- Taxon
- crabgrasse0
- Treatment
- aqueous methanol extract of neem leavese0
- Interactor
- neemAzadirachta indicae0other
- Outcome
- growth of roots and shootse0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“An aqueous methanol extract of neem leaves inhibited the growth of roots and shoots of cress, lettuce, alfalfa, timothy, crabgrass, ryegrass, barnyard grass and jungle rice.”
Claim · model-written summary
Neem leaf extract inhibited root and shoot growth of ryegrass.
- Treatment
- aqueous methanol extract of neem leavese0
- Interactor
- neemAzadirachta indicae0other
- Outcome
- growth of roots and shootse0
- Direction
- inhibitede0
LoliumNot reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“An aqueous methanol extract of neem leaves inhibited the growth of roots and shoots of cress, lettuce, alfalfa, timothy, crabgrass, ryegrass, barnyard grass and jungle rice.”
Claim · model-written summary
Neem leaf extract inhibited root and shoot growth of barnyard grass.
- Taxon
- barnyard grass
Echinochloa crus-gallie0 - Treatment
- aqueous methanol extract of neem leavese0
- Interactor
- neemAzadirachta indicae0other
- Outcome
- growth of roots and shootse0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“An aqueous methanol extract of neem leaves inhibited the growth of roots and shoots of cress, lettuce, alfalfa, timothy, crabgrass, ryegrass, barnyard grass and jungle rice.”
Claim · model-written summary
Neem leaf extract inhibited root and shoot growth of jungle rice.
- Taxon
- jungle rice
Echinochloa colonae0 - Treatment
- aqueous methanol extract of neem leavese0
- Interactor
- neemAzadirachta indicae0other
- Outcome
- growth of roots and shootse0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“An aqueous methanol extract of neem leaves inhibited the growth of roots and shoots of cress, lettuce, alfalfa, timothy, crabgrass, ryegrass, barnyard grass and jungle rice.”
Claim · model-written summary
Two phytotoxic substances were isolated from neem leaf extracts.
- Taxon
- Neem (Azadirachta indica)Azadirachta indicae1
- Outcome
- two phytotoxic substances were isolatede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The extracts were then purified by several chromatographic runs while monitoring the inhibitory activity and two phytotoxic substances were isolated.”
e1“Neem (Azadirachta indica)”
Claim · model-written summary
The isolated substances were identified as novel nimbolide B and nimbic acid B.
- Taxon
- Neem (Azadirachta indica)Azadirachta indicae1
- Outcome
- novel compounds, nimbolide B (1) and nimbic acid B (2)e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The chemical structures of the two substances were determined by spectral data to correspond to novel compounds, nimbolide B (1) and nimbic acid B (2).”
e1“Neem (Azadirachta indica)”
Claim · model-written summary
Nimbolide B inhibited cress growth above 0.1‒3.0 μM.
Not reportedComparator
Verbatim
e0“Nimbolide B inhibited the growth of cress and barnyard grass at concentrations greater than 0.1‒3.0 μM.”
Claim · model-written summary
Nimbolide B inhibited barnyard grass growth above 0.1‒3.0 μM.
- Taxon
- barnyard grassEchinochloa crus-gallie0
- Treatment
- Nimbolide Be0
- Outcome
- growthe0
- Direction
- inhibitede0
- Value
- 0.1‒3.0 μMe0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Nimbolide B inhibited the growth of cress and barnyard grass at concentrations greater than 0.1‒3.0 μM.”
Claim · model-written summary
Nimbic acid B inhibited cress growth above 0.3-1.0 μM.
Not reportedComparator
Verbatim
e0“Nimbic acid B inhibited the growth of cress and barnyard grass at concentrations greater than 0.3-1.0 μM.”
Claim · model-written summary
Nimbic acid B inhibited barnyard grass growth above 0.3-1.0 μM.
- Taxon
- barnyard grassEchinochloa crus-gallie0
- Treatment
- Nimbic acid Be0
- Outcome
- growthe0
- Direction
- inhibitede0
- Value
- 0.3-1.0 μMe0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Nimbic acid B inhibited the growth of cress and barnyard grass at concentrations greater than 0.3-1.0 μM.”
Claim · model-written summary
The authors suggest nimbolide B and nimbic acid B may contribute to neem leaf allelopathy.
- Taxon
- neemAzadirachta indicae0
- Compound
- nimbolide B and nimbic acid Be0
- Outcome
- allelopathic effectse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“These results suggest that nimbolide B and nimbic acid B may contribute to the allelopathic effects caused by neem leaves.”
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See all 271 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.