Green hairy roots

The inocula for these experiments were prepared by preculturing green hairy roots in MS liquid medium for 14 days at incident light intensity, I, of 11.1 W m 2 under the same conditions as mentioned above. 

Moreover, these enzyme activities declined along with the decreased Chi content when the green hairy roots were grown in the dark (data not shown). It... 

Table 2. Chi contents of green hairy roots derived from various plants... 

Histological examination was conducted to elucidate cellular changes in photoautotrophic and photomixotrophic green hairy roots stimulated by light. The Chi pigment [39] was found in the cortical cells of photoautotrophic hairy roots observed under a fluorescence microscope as compared with those of the photomixo troph. The heterotrophic hairy roots did not display the Chi pigment (data not shown). 

Production of cardenolides in green hairy root cultures of Digitalis lanata... 

Enhanced production of cardenolides was found in green hairy root cultures of D. lanata, though leaves and stems are the parts which accumulate cardenolides. In this chapter, production of cardenolides in the green hairy root cultures of D. lanata is described [116, 117]. In addition, correlation of chloroplast in the hairy roots with cardenolide production is presented [101]. 

The green hairy roots cultured in the light for 3 weeks were used for the fluorescent microscopy and transmission electron microscopy (TEM). For the fluorescent microscopy, frozen sections (15 pm in thickness) were prepared using microtome cryostat (HM 500 OM, Microme, Heidelberg, Germany) and sealed with 50% glycerol on glass slides. Localization of chloroplasts was observed by fluorescent microscopy (VANOX AH-3, Olympus). 

Fig. (58) shows the cross section and the longitudinal sections of the green hairy roots observed under the optic microscope and fluorescent microscope. It was noticed that though the green hairy roots were... 

Fig. (58). Cross (left) and longitudinal (right) sections of green hairy roots...

Chlorophylls in the green hairy roots were extracted with N,N -dimethylformamide and determined spectrophotometrically by the method of Porra et al. [125]. Rates of photosynthetic evolution of oxygen from green hairy roots were measured with a gas-phase oxygen-electrode system at an irradiance of 1000 pmol quanta/m /s, at a saturating concentration of CO2 (approximately 5%) and at 25 °C [126]. 

The chlorophyll content and rates of photosynthetic oxygen evolution of green hairy roots are presented in Table 19. The chlorophyll content per fresh weight basis was total 70 pg/g, which was lower than the value generally known for leaves. 

The plastids in green hairy roots had thylakoid membrane systems as shown above. Flores et al. [124] measured CO2 fixation as... 

Correlation between the cardenolide and chlorophyll contents in the green hairy root of D. lanata... 

It is well established that the digoxigenin glycosides accumulate far more in the mesophyll than in the epidermis and vascular bundles in D. lanata plants [128]. Therefore, the existence of chloroplasts or chloroplast-like plastids may play an important role in the accumulation of digoxigenin glycosides because the green hairy roots were... 

It is very interesting how these plastids in the green hairy roots differentiate in view of the multiformity of plastids. Therefore, further study is required to clarify this matter and to understand the physiological role of these plastids especially the effects on secondary metabolite production. 

Fig. (60). Cardenolide and chlorophyll contents in green hairy roots otD. lanata...

Chlorophylls and photosynthetic activity in the green hairy roots... 

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