Leaf-closing factor

The phenomenon of nyctinasty or plant sleep has been recorded since the ancient time of Alexander the Great.83 For example, the pinnate leaves of a large tamarind tree (Tamarindus indica) fold together at night as if the tree sleeps.83 In 1995 Yamamura and coworkers isolated 3.1 mg of phyllanthrinolactone (41, Figure 2.27) from 19.2 kg of the fresh nyctinastic plant Phyllanthus urinaria as its leaf-closing factor.84 It is bioactive only for that plant in the daytime at a very low concentration of 1 x 1(T7M. 

Isol. from Lespedeza cuneata. Leaf-closing factor (as K salt). 

Fig. 8.4 Time-course change in the concentration of leaf-opening and leaf-closing factors in Phyllanthus urinaria.

Nakamura, Y, Miyatake, R., Matsubara, A., Kiyota, H. Ueda, M. (2006a). Enantio-difFerential approach to identify the target cell for glucosyl jasmonate-type leaf-closing factor, by using fluorescence-labeled probe compounds. Tetrahedron, 62, 8805-8813. 

Nakamura, Y, Kiyota, H., Kumagai, T. Ueda, M. (2006b). Direct observation of the target cell for jasmonate-type leaf-closing factor genus-specific binding of leaf-movement factors to the plant motor cell. Tetrahedron Letters, 47,2893-2897. 

Ueda, M., Niwa, M. Yamamura, S. (1995a). Triconelline, a leaf-closing factor of the nyctinastic pXacA, Aeschynomene indica. Phytochemistry, 39, 817-819. 

The leaf-closing substance 79 has been isolated from a nyctinastic plant," and compound 80 is a new lignan glycoside isolated in tiny proportions from the roots of Saussurea lappa Xyloside 81 is a new glycoside isolated from the mycelia of Hericium erinaceum which contains compounds that stimulate nerve growth factor synthesis. Two derivatives were made by chemical transformations. 

The time-course changes in the content of leaf-closing and leaf-opening factors in the plant Phyllanthus urinaria are highlighted in Fig. 8.4 (Ueda et al., 1999a). HPLC was... 

In all of the five pairs of leaf-closing and leaf-opening factors 1-10 from the five nyc-tinastic plants discovered so far, one of each pair of factors is a glycoside, and in all cases, the concentrations of these glycoside-type leaf-movement factors change during the day in a manner similar to that described for L. cuneata. 

Stomatal closure was associated with a genetic factor in onion wherein the stomata of sensitive plants did not close. The effect of ozone and PAN on stomatal opening depends on many interacting factors those representing water stress appear to be the most important. Dean related stomatal density to the difference in sensitivity between two tobacco cultivars. Evans and Ting found that maximal sensitivity of bean primary leaves was not associated with changes in stomatal number or leaf resistance. Ozone exposure caused a decrease in relative water content, but no change in resistance. Bean leaf sensitivity seemed more a function of internal activities. 

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