21

Ginkgo biloba

Ginkgoaceae

2-hydroxy-6-(10-hydroxypentadec-11-enyl)benzoic acid

The IC₅₀ values of the compound for seedling growth inhibition for garden cress roots and shoots were 9.1 and 12 M, respectively, and that for timothy roots and shoots was 17 and 23 M, respectively. The activity of the compound was 10- to 52-fold that of nonanoic acid (a natural ester used for herbicide preparation) on those test species.

Kato-Noguchi et al. [129]

22

Cucumis sativus

Cucurbitaceae

9-hydroxy-4,7-megastigmadien-9-one (1); (6S,7E,9S)-6,9,10-trihydroxy-4,7-megastigmadien-3-one (2); (2S)-2,3-dihydro-2a-(4-hydroxy-3-methoxyphenyl)-7- methoxy-5-(1,2,3-trihydroxypropyl)benzofuran-3b-methanol (sisymbrifolin, 3)

The IC₅₀ values for root and shoot growth inhibition of cress and barnyard grass were 2.4 - 29.3 µM for compound 1 and 8.1 - 52.2 µM for compound 2.

The IC₅₀ values of compound 3 for root and shoot growth inhibition of cress and barnyard grass were 16.5 34.2 µM and 22.1 - 67.3 µM, respectively.

Kato-Noguchi et al. [130] , (Kato-Noguchi et al. [131]

23

Rhinacanthus nasutus

Acanthaceae

4-hydroxy-3-methoxybenzoic acid (vanillic acid)

The IC₅₀ values of vanillic acid for growth inhibition of cress and lettuce were about 470 - 800 μM and that for timothy and Italian ryegrass were 0.17 - 8.2 μM, respectively.

Piyatida et al. [132]

24

Tinospora tuberculata

Menispermaceae

4-[(1E)-3-Hydroxyprop-1-en-1-yl]-2,6-dimethoxyphenyl b-D-glucopyranoside (syringing)

The IC₅₀ values of syringing for root and shoot growth inhibition of garden cress and lettuce ranged from 78.2 to 412 μM, and that of timothy and barnyard grass ranged from 9.8 to 73.2 µM, respectively.

Kato-Noguchi et al. [133]

25

Piper sarmentosum

Piperaceae

3-phenylpropionic acid

The IC₅₀ values of 3-phenylpropionic acid for cress and lettuce were 1.2 - 9.3 μM and that of timothy and Italian ryegrass were 4.7 - 51.8 μM, respectively.

Piyatida et al. [134]

26

Onopordum acanthium

Asteraceae

Elemanolide 11(13)-dehydromelitensin b-hydroxyisobutyrate

Inhibited the coleoptile growth of wheat.

Watanabe et al. [135]