The present study was conducted to investigate the effect of agitation rate on the increase in fresh weight of MD2 pineapple protocorm-like bodies (PLBs) and shoots cultured in liquid medium. PLBs were cultured in 250...The present study was conducted to investigate the effect of agitation rate on the increase in fresh weight of MD2 pineapple protocorm-like bodies (PLBs) and shoots cultured in liquid medium. PLBs were cultured in 250 ml Erlenmeyer flasks (7 g per flask) containing MS medium and plant growth regulators (1.5 mg/L 6-Benzylaminopurine, BAP and 0.2 mg/L 1-Naphthaleneacetic acid, NAA). The orbital shaker was set at speeds of 50, 80, 100, 120, and 150 rpm. After 40 days, the cultures shaken at 80 rpm showed the highest fresh weight and the highest number of shoots at 76 g and 41 shoots, respectively. A comparative study of agitation found that 80 rpm was the best speed which enhanced both PLB and shoot formation. The findings in the present study would be helpful in setting up large-scale in vitro mass propagation of MD2 pineapple.展开更多
A mixed culture of moderately thermophilic microorganisms was enriched from acid mine drainages(AMDs)samples collected from several sulphide mines in China,and the bioleaching of chalcopyrite was conducted both in sha...A mixed culture of moderately thermophilic microorganisms was enriched from acid mine drainages(AMDs)samples collected from several sulphide mines in China,and the bioleaching of chalcopyrite was conducted both in shake flask and bioreactor.The results show that in the shake flask,the mixture can tolerate 50 g/L chalcopyrite after being acclimated to gradually increased concentrations of chalcopyrite.The copper extraction increases obviously in bioleaching of chalcopyrite with moderately thermophilic microorganisms supplemented with 0.4 g/L yeast extract at 180 r/min,74% copper can be extracted in the pulp of 50 g/L chalcopyrite after 20 d.Compared with copper extractions of mesophilic culture,unacclimated culture and acclimated culture without addition of yeast extract,that of accliniated culture with addition of yeast extract is increased by 53%,44% and 16%,respectively.In a completely stirred tank reactor,the mass fraction of copper and total iron extraction reach up to 81% and 56%,respectively.The results also indicate that it is necessary to add a large amount of acid to the pulp to extract copper from chalcopyrite effectively.展开更多
A culture system was developed and successfully employed for the serum-free cultivation of Tn-5B1-4 (Tn5 ) insect cells. With our adaptation procedure, it was possible to obtain cells fully adapted to serum-free media...A culture system was developed and successfully employed for the serum-free cultivation of Tn-5B1-4 (Tn5 ) insect cells. With our adaptation procedure, it was possible to obtain cells fully adapted to serum-free media in stationary T-flasks and then enable these adapted cells to grow well in spinner flasks immediately. The spinner "ask with special stirring design proved tO provide favorable culture environment that made it desirable for use in the serum-free cultivation of Tn5 cells even at low seeding density.展开更多
Short Retraction NoticeThis article has been retracted to straighten the academic record. In making this decision the Editorial Board follows COPE's Retraction Guidelines. The aim is to promote the circulation of ...Short Retraction NoticeThis article has been retracted to straighten the academic record. In making this decision the Editorial Board follows COPE's Retraction Guidelines. The aim is to promote the circulation of scientific research by offering an ideal research publication platform with due consideration of internationally accepted standards on publication ethics. The Editorial Board would like to extend its sincere apologies for any inconvenience this retraction may have caused. The full retraction notice in PDF is preceding the original paper, which is marked "RETRACTED".展开更多
文摘The present study was conducted to investigate the effect of agitation rate on the increase in fresh weight of MD2 pineapple protocorm-like bodies (PLBs) and shoots cultured in liquid medium. PLBs were cultured in 250 ml Erlenmeyer flasks (7 g per flask) containing MS medium and plant growth regulators (1.5 mg/L 6-Benzylaminopurine, BAP and 0.2 mg/L 1-Naphthaleneacetic acid, NAA). The orbital shaker was set at speeds of 50, 80, 100, 120, and 150 rpm. After 40 days, the cultures shaken at 80 rpm showed the highest fresh weight and the highest number of shoots at 76 g and 41 shoots, respectively. A comparative study of agitation found that 80 rpm was the best speed which enhanced both PLB and shoot formation. The findings in the present study would be helpful in setting up large-scale in vitro mass propagation of MD2 pineapple.
基金Project(50621063, 40646029) supported by the National Natural Science Foundation of ChinaProject (2004CB619204) supported by the National Basic Research Program
文摘A mixed culture of moderately thermophilic microorganisms was enriched from acid mine drainages(AMDs)samples collected from several sulphide mines in China,and the bioleaching of chalcopyrite was conducted both in shake flask and bioreactor.The results show that in the shake flask,the mixture can tolerate 50 g/L chalcopyrite after being acclimated to gradually increased concentrations of chalcopyrite.The copper extraction increases obviously in bioleaching of chalcopyrite with moderately thermophilic microorganisms supplemented with 0.4 g/L yeast extract at 180 r/min,74% copper can be extracted in the pulp of 50 g/L chalcopyrite after 20 d.Compared with copper extractions of mesophilic culture,unacclimated culture and acclimated culture without addition of yeast extract,that of accliniated culture with addition of yeast extract is increased by 53%,44% and 16%,respectively.In a completely stirred tank reactor,the mass fraction of copper and total iron extraction reach up to 81% and 56%,respectively.The results also indicate that it is necessary to add a large amount of acid to the pulp to extract copper from chalcopyrite effectively.
文摘A culture system was developed and successfully employed for the serum-free cultivation of Tn-5B1-4 (Tn5 ) insect cells. With our adaptation procedure, it was possible to obtain cells fully adapted to serum-free media in stationary T-flasks and then enable these adapted cells to grow well in spinner flasks immediately. The spinner "ask with special stirring design proved tO provide favorable culture environment that made it desirable for use in the serum-free cultivation of Tn5 cells even at low seeding density.
文摘Short Retraction NoticeThis article has been retracted to straighten the academic record. In making this decision the Editorial Board follows COPE's Retraction Guidelines. The aim is to promote the circulation of scientific research by offering an ideal research publication platform with due consideration of internationally accepted standards on publication ethics. The Editorial Board would like to extend its sincere apologies for any inconvenience this retraction may have caused. The full retraction notice in PDF is preceding the original paper, which is marked "RETRACTED".
