Table I.
Comparison of cytoplasmic acidification, K+ efflux, and appearance of benzophenanthridine alkaloids in suspension cultures of Californian poppy
| Treatment | Acidification of Cytoplasm/Nucleus | K+ Loss Initial Rate | Alkaloid Production per 24 h |
|---|---|---|---|
| maximum pH shift | μm min−1 g−1 dry wt | %, normalizeda | |
| Control | 0 | 0 | 15 (6) |
| Yeast elicitor (30–100 kD) | |||
| 1 μg/mL | 0.55 (5) | 0.02 (5) | 100 (6) |
| 3 μg/mL | 0.60 (4) | 3.1 (5) | 114 (5) |
| Valinomycin 1 μm | <0.1 (3) | 2.4 (5) | 19 (4) |
| Valinomycin 5 μm | 0.40 (2) | 3.2 (2) | 40 (2) |
| Valinomycin 10 μm | 1.05 (3) | 4.5 (4) | 93 (3) |
| Butyric acid (2 mm, 10 min) | 0.35 (4) | 0.0 (3) | 62 (5) |
| Pivalic acid (2 mm, 10 min) | 0.40 (2) | n.d.b | 70 (3) |
Effectors were added to the growth medium of 4- or 5-d cultures (external pH = 3.8–4.0). Each figure is averaged from three determinations with the same batch of cell suspensions. The sd values were as follows: alkaloid content, 6% to 9%, cytoplasmic pH, 0.03 unit; and K+ loss, 10% to 12%. Independent experiments with different batches of cell suspensions (numbers in parentheses) yielded similar results.
The highest variability was found with the alkaloid production of different batches, the extremes of which were as follows: initial content, 70 to 120 μg/g; increase per 24 h (control), 30 to 54 μg/g; increase per 24 h (1 μg elicitor/mL), 210 to 360 μg/g. To keep the data on alkaloid contents comparable, figures are normalized to the alkaloid production evoked by 1 μg/mL crude elicitor, which is set to 100%.
n.d., Not determined.