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Rozita Omar M. A. Abdullah M. A. Hasan M. Rosfarizan M. Marziah 《Biotechnology and Bioprocess Engineering》2006,11(3):223-229
In this study, we have conducted kinetics and modelling studies ofCentella asiatica cell growth and substrate uptake, in an attempt to evaluate cell growth for a better understanding and control of the process.
In our bioreactor cultivation experiment, we observed a growth rate of 0.18/day, a value only 20% higher than was seen in
the shake flask cultivation trial. However, the observed maximum cell dry weight in the shake flask, 10.5 g/L, was 14% higher
than was achieved in the bioreactor. Ninety seven percentage confidence was achieved via the fitting of three unstructured
growth models; the Monod, Logistic, and Gompertz equations, to the cell growth data. The Monod equation adequately described
cell growth in both cultures. The specific growth rate, however, was not effectively predicted with the Logistic and Gompertz
equations, which resulted in deviations of up to 73 and 393%, respectively. These deviations in the Logistic and Gompertz
models may be attributable to the fact that these models were developed for substrate-independent growth and fungi growth,
respectively. 相似文献
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Three different morphological callus types, identified as type A, B and C, and tips of in vitro inflorescences were used as target tissues for genetic transformation. Five different DNA plasmids carrying a synthetic green fluorescent protein (gfp) gene driven by different promoters, CaMV 35S, HBT, and Ubi1 were tested for the genetic transformation of Dendrobium Sonia 17. 35S-sgfp-TYG-nos (p35S) with the CaMV 35S promoter showed the highest GFP transient expression rate, while the HBT and Ubi1 promoters showed a relatively lower expression rate in all of the target tissues tested. The highest number of GFP-expressing cells was observed on day 2 post-bombardment, and the number declined gradually over the course of the next 2 weeks. Type A and B callus were found to be the best potential target tissues for genetic transformation. 相似文献
3.
Rozita Omar M. A. Abdullah M. A. Hasan M. Marziah M. K. Siti Mazlina 《Biotechnology and Bioprocess Engineering》2005,10(3):192-197
The effects of macronutrients (NO3
−, NH4
+ and PO4
3−) on cell growth and triterpenoids production inCentella asiatica cell suspension cultures were analyzed using the Box-Behnken response surface model experimental design. In screening and
optimization experiments, PO4
3− as a single factor significantly influenced cell growth where increasing the phosphate level from 0.1 to 2.4 or 2.6 mM, elevated
cell growth from 3.9 to 14–16 g/L. The optimum values predicted from the response surface model are 5.05 mM NH4
+, 15.0 mM NO3
− and 2.6 mM PO4
3−, yielding 16.0 g/L cell dry weight with 99% fitness to the experimental data. While the NH4
+-NO3
− interaction influenced cell growth positively in the optimization experiment, NH4
+ and NO3
− as single factors; and interactions of NO3
−-PO4
3−, NH4
+-PO4
3− and NH4
+-NO3
− were all negative in the screening experiment. Cell growth and the final pH level were positively affected by PO4
3−, but negatively affected by NH4
+ and NH4
+-PO4
3− interactions. The different effects of factors and their interactions on cell growth and final pH are influenced by a broad
or narrow range of macronutrient concentrations. The productions of triterpenoids however were lower than 4 mg/g cell dry
weight. 相似文献
4.
Abdullah M.A. Ali A.M. Marziah M. Lajis N.H. Ariff A.B. 《Plant Cell, Tissue and Organ Culture》1998,54(3):173-182
Morinda elliptica (Rubiaceae) cell suspension cultures were established in shake flask system for the production of anthraquinones.
The optimized medium formulation for cell growth and anthraquinone production is proposed. Murashige and Skoog's basal medium
(MS) was found to be the best medium, used in combination with 0.5 mg l-1 NAA and 0.5 mg l-1 kinetin. At the range of sucrose
concentration tested (3–8% w/v), 8% was the best in enhancing both cell growth and anthraquinone production. A strategy to
formulate growth and production medium by manipulating culture age and inoculum age, the type of medium formulation used to
grow inoculum, incubation temperature and light intensity was established. By using 18 month old culture and 7 day old inoculum
at incubation temperature of 27 ± 3 °C, anthraquinone yield of 2.9 g l-1 and 4.5 g l-1, under illumination of 1200 lux and
in the dark was obtained, respectively.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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6.
Abdullah M.A. Ariff A.B. Marziah M. Ali A.M. Lajis N.H. 《Plant Cell, Tissue and Organ Culture》2000,60(3):205-212
Strategies to overcome foaming and wall-growth during the cultivation of Morinda elliptica (Rubiaceae) cell suspension cultures in a stirred-tank bioreactor are described. Of all the strategies applied, only bubble-free
aeration was successful in eliminating foaming by 100%. Despite the foaming effect of around 40% in G medium strategy with
0.012% (v/v) antifoam, the maximum dry cell weight attained (19.2 g l-1) and anthraquinone (AQ) content (4.0 mg g-1 DW) was nearly three times higher than that achieved in cultivation using 0.025% (v/v) antifoam. For continuous cell growth,
the effect of inoculum age should also be considered when anti-foam is to be added. P medium strategy, without antifoam addition,
not only promoted both growth (18 g l-1) and AQ production (9.8 mg g-1 DW), but also resulted in lower foaming and wall-growth (below 30% level), and higher foaming reduction (30–40%).
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
7.
Jualang Azlan G. Marziah M. Radzali M. Johari R. 《Plant Cell, Tissue and Organ Culture》2002,69(3):271-278
This report describes the technique used to induce the hairy roots in Physalis minima (Linn.). Different types of explants obtained from in vitro germinated seedlings were aseptically co-cultivated with A. rhizogenesstrain LBA9402 in different media. Root growth and production of physalins were investigated in various basal media grown under dark and light conditions, and compared to that of normal root cultures. Transformed hairy root cultures grew rapidly and reach stationary phase after 15 days on a B5 medium. HPLC analysis of extracts of hairy root cultures showed that the maximum content of physalin B and F was 1.82 and 4.15 mg g–1 DW, respectively, when grown under dark conditions. Normal root cultures produced higher physalin B (1.60–1.62 mg g–1 DW) and F (3.30–3.75 mg g–1 DW) under the same culture conditions. Physalin F synthesis in light-grown root cultures was reduced significantly. 相似文献
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