Photoautotrophic cultures

Keywords. Plant cell culture, Pak-bung hairy roots, Photoautotrophic culture, Light irradiation 1 Introduction. 186... 

The photoautotrophic cultures were carried out at 25 °C using 250-cm3 flat, oblong glass flasks containing 50 cm3 of MS liquid medium. The hairy roots... 

Photomixotrophic and photoautotrophic cultures of pak-bung hairy roots were performed at various incident light intensities. 

In the case of photoautotrophic cultures of pak-bung hairy roots at light intensities of 1=0-31 W nr2, as shown in Fig. 16, as expected, no growth of the hairy roots was observed in the dark. X values increased with increasing I... 

Figure 20 shows the relationship between the values of root length, L, and initial elongation rate of growing points, kGI, in the photoautotrophic cultures of pak-bung hairy roots. The kGI values increased with increasing L values and appa-... 

In photoautotrophic culture of microalgae, CO2 is a sole carbon source for the growth. CO2 supplied to the suspension culture of microalgae is first dissolved to the medium and utilized by the cells. In usual culture operation of microalgae, gas mixture containing CO2 is continuously supplied to the medium. As CO2 supply rate is more than CO2 consumption rate by the cells, most of supplied CO2 escapes to the atmosphere. 

In photoautotrophic cultures of microalgae, the ratio of CO2 fixed by the cells was improved by means of regulating gas supply rate corresponding to the pH value of the medium. 

Dceda, H., Culture vessel for photoautotrophic culture, Japan Patent, Kokai 60-237984(1985)... 

Yoneyama K, Nakajima Y, Maejima N et al. Simple and rapid screening method for Photosystem II inhibitory herbicides using photoautotrophically cultured plant cells with chlorophyll fluorescence monitoring. Biosci Biotech Biochem 1993 57(8) 1389-1390. 

Cultures of S. obliquus can easily be grown photoautotrophically in two-tier flasks in an inorganic medium. A stepwise replacement of H20 by 2H20 leads to deuterated cultures, and a replacement of C02 (the sole carbon source) by 13C02 and/or the replacement of... 

Schwenger-Erger, C., J. Thiemann, W. Barz, U. Johanningmeier, and D. Naber (1993). Metribuzin resistance in photoautotrophic Chenopodium rubrum cell cultures. FEBS Lett., 329 43-46. 

To derive a cell line of photoautotrophic hairy roots, successive cultures of the photomixotrophic hairy roots were performed under the conditions of plain air (0.03% C02) and C02-enriched air (3.0% C02), and the initial concentration of sucrose, CSI, as a carbon source was lowered in a stepwise manner, that is, CSI= 10 (1st stage for 0-14 days), 5.0 (2nd stage for 14-28 days), 2.5 (3rd stage for 28-42 days), and 0 kg nr3 (4th stage for 42-56 days). 

On the other hand, in the cultures under 3.0% C02 atmosphere, the values of Cqjj and Ar in the hairy roots increased at every culture stage accompanying the decrease in the initial sucrose concentration in the medium as shown in Fig. 3B. At the end of the 2nd and 3rd stages, the sugars (sucrose, glucose, and fructose) were completely consumed in the medium (data not shown). It was thus considered that the hairy roots were acclimating to the photoautotrophic condition... 

Thus far, most photoautotrophic plant cells have been induced in cultures of calli or suspension cells [21,35-38]. Concerning plant hairy roots, Flores et al. [34] obtained the cell lines of photoautotrophic hairy roots of A. oppositifolia and D. innoxia through acclimation cultures with changes in sugar concentration in the medium and C02 tension in gas phase. However, detailed examinations have not been made to clarify the effects of culture conditions on the growth and photosynthetic activity of those photoautotrophic hairy roots. 

Fig. 17. Time profiles of the number of viable growing points at various incident light intensities in photoautotrophic hairy root cultures...

Cultivations are usually carried out in submerged cultures in bioreactors. Fungi can be cultivated on solid wastes such as straw. In those countries which have enough land and1 sun, and in regions where naturally alkaline lakes are present, SCP from photoautotrophically grown algae could be economically feasible. 

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