Influence of the combination of nutrient feed with dissolved oxygen control on taxol production in suspension cultures of Taxus chinensis (Pilg.) Rehd. was investigated in bioreactors. Addition of feeding medium with ...Influence of the combination of nutrient feed with dissolved oxygen control on taxol production in suspension cultures of Taxus chinensis (Pilg.) Rehd. was investigated in bioreactors. Addition of feeding medium with 20 g/L sucrose on day 16 enhanced both the biomass and taxol production in 5-L bioreactors. Further investigation of the fed-batch cultures in a 20-L bioreactor showed that cultivation under a low dissolved oxygen tension (DOT) of 20% for the entire culture resulted in the highest taxol content of 0.98 mg/g DW, while the taxol production was lower than that with 40% and 60% DOT. Moreover, taxol accumulation was remarkably improved by the cultivation of cells initially under DOT of 60% for 20 d followed by changing the DOT to 20% for another 12 d. By combining the use of these two strategies, a maximum taxol content of 18.7 mg/L was obtained in a 20-L bioreactor.展开更多
The potential allelopathic effects of the microalga,Phaeocystis globosa Scherffel,on three harmful bloom algae,Prorocentrum donghaiense Lu,Chattonella marina(Subrahmanyan) Hara et Chihara and Chattonella ovata Hara et...The potential allelopathic effects of the microalga,Phaeocystis globosa Scherffel,on three harmful bloom algae,Prorocentrum donghaiense Lu,Chattonella marina(Subrahmanyan) Hara et Chihara and Chattonella ovata Hara et Chihara were studied.The growth of C.marina and C.ovata was markedly reduced when the organisms were co-cultured with P.globosa or cultured in cell-free spent medium.Haemolytic extracts from P.globosa cells in the senescence phase had a similar inhibitory effect on the three harmful bloom algae.However,P.globosa had less influence on the brine shrimp,Artemia salina.These results indicate that P.globosa may have an allelopathic effect on microalgae,which would explain the superior competitive abilities of P.globosa.Because the addition of the haemolytic toxins from P.globosa had similar effects on algae as spent media,these compounds may be involved in the allelopathic action of P.globosa.展开更多
文摘Influence of the combination of nutrient feed with dissolved oxygen control on taxol production in suspension cultures of Taxus chinensis (Pilg.) Rehd. was investigated in bioreactors. Addition of feeding medium with 20 g/L sucrose on day 16 enhanced both the biomass and taxol production in 5-L bioreactors. Further investigation of the fed-batch cultures in a 20-L bioreactor showed that cultivation under a low dissolved oxygen tension (DOT) of 20% for the entire culture resulted in the highest taxol content of 0.98 mg/g DW, while the taxol production was lower than that with 40% and 60% DOT. Moreover, taxol accumulation was remarkably improved by the cultivation of cells initially under DOT of 60% for 20 d followed by changing the DOT to 20% for another 12 d. By combining the use of these two strategies, a maximum taxol content of 18.7 mg/L was obtained in a 20-L bioreactor.
基金Supported by the NSFC-Guangdong Province Association Foundation(No.U0733006)the National Natural Science Foundation of China(No.30970502)the State Key Laboratory of Marine Environmental Science(Xiamen University MEL0403)
文摘The potential allelopathic effects of the microalga,Phaeocystis globosa Scherffel,on three harmful bloom algae,Prorocentrum donghaiense Lu,Chattonella marina(Subrahmanyan) Hara et Chihara and Chattonella ovata Hara et Chihara were studied.The growth of C.marina and C.ovata was markedly reduced when the organisms were co-cultured with P.globosa or cultured in cell-free spent medium.Haemolytic extracts from P.globosa cells in the senescence phase had a similar inhibitory effect on the three harmful bloom algae.However,P.globosa had less influence on the brine shrimp,Artemia salina.These results indicate that P.globosa may have an allelopathic effect on microalgae,which would explain the superior competitive abilities of P.globosa.Because the addition of the haemolytic toxins from P.globosa had similar effects on algae as spent media,these compounds may be involved in the allelopathic action of P.globosa.
