Applied Microbiology and Biotechnology, Feb 1, 1992
Sanguinaria canadensis L. plants were harvested from a local forest and calli were initiated from... more Sanguinaria canadensis L. plants were harvested from a local forest and calli were initiated from leaf explants. The production of benzophenanthridine alkaloids (i.e. sanguinarine, sanguilutine, sanguirubine, chelerythrine, chelilutine and chelirubine) by S. canadensis cell grown in modified B5 and IM2 media was compared to the alkaloid content of rhizomes. Sanguinarine accounted for approximately 80% of the total alkaloid content of cultured cells (1.3%, g g-1) while sanguinarine and sanguirubine accounted for 70% of rhizome alkaloids (9.0%, g g-1). Sanguinarine, chelirubine and chelerythrine were the only known alkaloids detected in cultured S. canadensis cells. Maximum alkaloid production of cultures performed using B5 medium, containing half the original nitrate concentration, was observed following extracellular nitrate and sugar depletion. The scale-up of this culture was successfully performed in a 2-1 immobilization bioreactor. The consumption of sugar and nitrate as well as the oxygen (OTR) and carbon dioxide (CTR) transfer rates of the immobilized cell culture were monitored for 15 days. The maximum sugar and nitrate consumption rates were 1.8 g l-1 per day and 2.3 mM per day respectively. The maximum OTR and CTR of the immobilized cell culture were 0.8 mmol O2 l-1 h-1 and 0.95 mmol CO2 l-1 h-1 respectively. The sanguinarine yield of this culture reached 1.0% based on biomass dry weight (g g-1 dw) by day 15.
When TNT (N-source) was treated with anaerobic sludge it biotransformed into triaminotoluene (TAT... more When TNT (N-source) was treated with anaerobic sludge it biotransformed into triaminotoluene (TAT) in high yield (80%). Results of experiments using 13C-labeling indicate that denitrated or deaminated products such as p-cresol and toluene were not formed. Whereas 14C-labeling showed negligible mineralization (<0.1% 14CO2) despite the complete disappearance of TNT. On the other hand, when TNT (175 µM) was treated with the fungus Phanerochaete chrysosporium it disappeared completely in less than two weeks, but mineralization (liberated 14CO2) did not exceed 1%. Several intermediates, marked with the initial formation of the two monohydroxylamino-dinitrotoluene (HADNT) followed by their transformation to monoamino-dinitrotoluenes (ADNT), diamines (DANT), acetylated TNT products, and azo and hydrazo derivatives were detected. In contrast, high concentrations (ca 20,000 ppm) of RDX and HMX were effectively degraded (ca 70%) in soil slurries using municipal anaerobic sludge. RDX and HMX disappearance was accompanied by the elimination of toxicity associated with RDX and HMX as determined by the Microtox test. Keywords Bioremediation; explosives; intermediates; mineralization; P. chrysosporium; Rhodococcus; sludge
When TNT (N-source) was treated with anaerobic sludge it biotransformed into triaminotoluene (TAT... more When TNT (N-source) was treated with anaerobic sludge it biotransformed into triaminotoluene (TAT) in high yield (80%). Results of experiments using 13C-labeling indicate that denitrated or deaminated products such as p-cresol and toluene were not formed. Whereas 14C-labeling showed negligible mineralization (<0.1% 14CO2) despite the complete disappearance of TNT. On the other hand, when TNT (175 µM) was treated with the fungus Phanerochaete chrysosporium it disappeared completely in less than two weeks, but mineralization (liberated 14CO2) did not exceed 1%. Several intermediates, marked with the initial formation of the two monohydroxylamino-dinitrotoluene (HADNT) followed by their transformation to monoamino-dinitrotoluenes (ADNT), diamines (DANT), acetylated TNT products, and azo and hydrazo derivatives were detected. In contrast, high concentrations (ca 20,000 ppm) of RDX and HMX were effectively degraded (ca 70%) in soil slurries using municipal anaerobic sludge. RDX and HMX disappearance was accompanied by the elimination of toxicity associated with RDX and HMX as determined by the Microtox test. Keywords Bioremediation; explosives; intermediates; mineralization; P. chrysosporium; Rhodococcus; sludge
... FOOD CHEM. 14, 460 (1966). Kahn, JH, Shipley, P. A., LaRoe, E. G., Conner, H. A,, J. Food Mar... more ... FOOD CHEM. 14, 460 (1966). Kahn, JH, Shipley, P. A., LaRoe, E. G., Conner, H. A,, J. Food Martin, MF, Vayreda, XM, An. Bromatol. (Madrid) 19, 39 Sci. 34, 587 (1969). (1 967). ... Browning Reaction in Model Systems Under Various Conditions Karl Eichnerl and Marcus Karel* ...
... METHODS Jianzhong Yang, Marie-Josée Lorrain, Denis Rho, and Peter CK Lau ... 14. Scarff M, A... more ... METHODS Jianzhong Yang, Marie-Josée Lorrain, Denis Rho, and Peter CK Lau ... 14. Scarff M, Arnold S, Harvey L, and McNeil B. Near-infrared spectroscopy for bio-process monitoring and control: Current status and future trends. Crit Rev Biotechnol 26, 17-39 (2006). 15. ...
Calli were obtained from Ginkgo biloba embryos grown on Murashige and Skoog (MS) medium. The G. b... more Calli were obtained from Ginkgo biloba embryos grown on Murashige and Skoog (MS) medium. The G. biloba cells could grow on either MS or Gamborg B5 mineral salt medium supplemented with sucrose (3% and 2%, respectively) and naphthaleneacetic acid (NAA) and kinetin (K) in concentrations ranging from 0.1 to 2.0 mg·L(-1). Best growth and maintenance of callus cultures were achieved using MS medium supplemented with 2 mg·L(-1) NAA and 1 mg·L(-1) K (N2K1MS). Light was required to maintain healthy growth of the callus tissue.In both MS and B5 based media, sucrose was hydrolyzed extracellularly before being taken up by Ginkgo cell suspension cultures. Specific growth rates of 0.13 d(-1) and 0.08 d(-1) were obtained in MS medium supplemented with 1 mg·L(-1) NAA, 0.1 mg·L(-1) K and 30 g·L(-1) sucrose (N1K0.1MS) and B5 medium supplemented with the same growth regulator regime and 20 g·L(-1) sucrose (N1K0.1B5) respectively. Complete phosphate and ammonium uptake was observed in 11 days when cultured in MS medium and 10 days and 4 days respectively when cultured in B5 medium. During the culture, G. biloba cells consumed only 64% and 29% of the nitrate content of N1K0.1MS and N1K0.1B5 media respectively. Maximum dry biomass concentrations were 13.4 g·L(-1) and 7.9 g·L(-1), and yields on carbohydrate were 0.39 and 0.45 in N1K0.1MS and N1K0.1B5 media respectively. The better performance of MS cultures came from the higher sucrose and nitrogen salts concentrations of this medium.
Applied Microbiology and Biotechnology, Feb 1, 1992
Sanguinaria canadensis L. plants were harvested from a local forest and calli were initiated from... more Sanguinaria canadensis L. plants were harvested from a local forest and calli were initiated from leaf explants. The production of benzophenanthridine alkaloids (i.e. sanguinarine, sanguilutine, sanguirubine, chelerythrine, chelilutine and chelirubine) by S. canadensis cell grown in modified B5 and IM2 media was compared to the alkaloid content of rhizomes. Sanguinarine accounted for approximately 80% of the total alkaloid content of cultured cells (1.3%, g g-1) while sanguinarine and sanguirubine accounted for 70% of rhizome alkaloids (9.0%, g g-1). Sanguinarine, chelirubine and chelerythrine were the only known alkaloids detected in cultured S. canadensis cells. Maximum alkaloid production of cultures performed using B5 medium, containing half the original nitrate concentration, was observed following extracellular nitrate and sugar depletion. The scale-up of this culture was successfully performed in a 2-1 immobilization bioreactor. The consumption of sugar and nitrate as well as the oxygen (OTR) and carbon dioxide (CTR) transfer rates of the immobilized cell culture were monitored for 15 days. The maximum sugar and nitrate consumption rates were 1.8 g l-1 per day and 2.3 mM per day respectively. The maximum OTR and CTR of the immobilized cell culture were 0.8 mmol O2 l-1 h-1 and 0.95 mmol CO2 l-1 h-1 respectively. The sanguinarine yield of this culture reached 1.0% based on biomass dry weight (g g-1 dw) by day 15.
When TNT (N-source) was treated with anaerobic sludge it biotransformed into triaminotoluene (TAT... more When TNT (N-source) was treated with anaerobic sludge it biotransformed into triaminotoluene (TAT) in high yield (80%). Results of experiments using 13C-labeling indicate that denitrated or deaminated products such as p-cresol and toluene were not formed. Whereas 14C-labeling showed negligible mineralization (<0.1% 14CO2) despite the complete disappearance of TNT. On the other hand, when TNT (175 µM) was treated with the fungus Phanerochaete chrysosporium it disappeared completely in less than two weeks, but mineralization (liberated 14CO2) did not exceed 1%. Several intermediates, marked with the initial formation of the two monohydroxylamino-dinitrotoluene (HADNT) followed by their transformation to monoamino-dinitrotoluenes (ADNT), diamines (DANT), acetylated TNT products, and azo and hydrazo derivatives were detected. In contrast, high concentrations (ca 20,000 ppm) of RDX and HMX were effectively degraded (ca 70%) in soil slurries using municipal anaerobic sludge. RDX and HMX disappearance was accompanied by the elimination of toxicity associated with RDX and HMX as determined by the Microtox test. Keywords Bioremediation; explosives; intermediates; mineralization; P. chrysosporium; Rhodococcus; sludge
When TNT (N-source) was treated with anaerobic sludge it biotransformed into triaminotoluene (TAT... more When TNT (N-source) was treated with anaerobic sludge it biotransformed into triaminotoluene (TAT) in high yield (80%). Results of experiments using 13C-labeling indicate that denitrated or deaminated products such as p-cresol and toluene were not formed. Whereas 14C-labeling showed negligible mineralization (<0.1% 14CO2) despite the complete disappearance of TNT. On the other hand, when TNT (175 µM) was treated with the fungus Phanerochaete chrysosporium it disappeared completely in less than two weeks, but mineralization (liberated 14CO2) did not exceed 1%. Several intermediates, marked with the initial formation of the two monohydroxylamino-dinitrotoluene (HADNT) followed by their transformation to monoamino-dinitrotoluenes (ADNT), diamines (DANT), acetylated TNT products, and azo and hydrazo derivatives were detected. In contrast, high concentrations (ca 20,000 ppm) of RDX and HMX were effectively degraded (ca 70%) in soil slurries using municipal anaerobic sludge. RDX and HMX disappearance was accompanied by the elimination of toxicity associated with RDX and HMX as determined by the Microtox test. Keywords Bioremediation; explosives; intermediates; mineralization; P. chrysosporium; Rhodococcus; sludge
... FOOD CHEM. 14, 460 (1966). Kahn, JH, Shipley, P. A., LaRoe, E. G., Conner, H. A,, J. Food Mar... more ... FOOD CHEM. 14, 460 (1966). Kahn, JH, Shipley, P. A., LaRoe, E. G., Conner, H. A,, J. Food Martin, MF, Vayreda, XM, An. Bromatol. (Madrid) 19, 39 Sci. 34, 587 (1969). (1 967). ... Browning Reaction in Model Systems Under Various Conditions Karl Eichnerl and Marcus Karel* ...
... METHODS Jianzhong Yang, Marie-Josée Lorrain, Denis Rho, and Peter CK Lau ... 14. Scarff M, A... more ... METHODS Jianzhong Yang, Marie-Josée Lorrain, Denis Rho, and Peter CK Lau ... 14. Scarff M, Arnold S, Harvey L, and McNeil B. Near-infrared spectroscopy for bio-process monitoring and control: Current status and future trends. Crit Rev Biotechnol 26, 17-39 (2006). 15. ...
Calli were obtained from Ginkgo biloba embryos grown on Murashige and Skoog (MS) medium. The G. b... more Calli were obtained from Ginkgo biloba embryos grown on Murashige and Skoog (MS) medium. The G. biloba cells could grow on either MS or Gamborg B5 mineral salt medium supplemented with sucrose (3% and 2%, respectively) and naphthaleneacetic acid (NAA) and kinetin (K) in concentrations ranging from 0.1 to 2.0 mg·L(-1). Best growth and maintenance of callus cultures were achieved using MS medium supplemented with 2 mg·L(-1) NAA and 1 mg·L(-1) K (N2K1MS). Light was required to maintain healthy growth of the callus tissue.In both MS and B5 based media, sucrose was hydrolyzed extracellularly before being taken up by Ginkgo cell suspension cultures. Specific growth rates of 0.13 d(-1) and 0.08 d(-1) were obtained in MS medium supplemented with 1 mg·L(-1) NAA, 0.1 mg·L(-1) K and 30 g·L(-1) sucrose (N1K0.1MS) and B5 medium supplemented with the same growth regulator regime and 20 g·L(-1) sucrose (N1K0.1B5) respectively. Complete phosphate and ammonium uptake was observed in 11 days when cultured in MS medium and 10 days and 4 days respectively when cultured in B5 medium. During the culture, G. biloba cells consumed only 64% and 29% of the nitrate content of N1K0.1MS and N1K0.1B5 media respectively. Maximum dry biomass concentrations were 13.4 g·L(-1) and 7.9 g·L(-1), and yields on carbohydrate were 0.39 and 0.45 in N1K0.1MS and N1K0.1B5 media respectively. The better performance of MS cultures came from the higher sucrose and nitrogen salts concentrations of this medium.
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