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Table 1 Comparison of cell growth, sporulation and δ-endotoxin production by Bacillus thuringiensis MPK13 in batch and fed-batch cultivations

From: Effect of different fermentation strategies on Bacillus thuringiensis cultivation and its toxicity towards the bagworm, Metisa plana Walker (Lepidoptera: Psychidae)

Fermentation modeMax cell count (× 1011 CFU/ml)Max spore count (× 1011 spore/ml)Increase in cell count (%)aDecrease in spore count (%)bδ-endotoxinMax percentage of sporulation (%)Max cell productivity (× 108 CFU/l/h)Max spore productivity (× 108 spore/l/h)
Batch13.9 (48 h)5.2 (48 h)00Yes (36 h)37 (48 h)72.424.5
Fed-batch Feed during:
 1) Lag phase (2 h)14.7 (48 h)3.7 (48 h)5.828.8Yes (48 h)25 (48 h)73.419.3
 2) Log phase (6 h)15.8 (40 h)3.9 (48 h)13.725.0Yes (48 h)25 (48 h)98.820.3
 3) Stationary phase (24 h)16.1 (48 h)3.1 (48 h)15.840.0No21.5 (24 h)83.916.1
Intermittent fed-batch17.2 (48 h)2.6 (48 h)23.750.0No15.2 (36 h)89.613.5
  1. aThe increase (%) was calculated based on batch fermentation
  2. bThe decrease (%) was calculated in comparison with batch cultivation data