• Korean Chemical Engineering Research
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• v.57 no.2
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• pp.219-224
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• 2019

In this study, the adsorption characteristics of cephalomannine on commercial adsorbent Sylopute were investigated using different parameters such as adsorption temperature, time, and initial cephalomannine concentration for the efficient separation of Taxus chinensis-derived cephalomannine by adsorption process. The Temkin isotherm model showed good fit to the equilibrium adsorption data. The adsorption capacity decreased with increasing temperature and the adsorption of cephalomannine onto Sylopute was physical in nature. Adsorption kinetic data fitted well with pseudo-second-order kinetic mode. According to the intraparticle diffusion model, film diffusion and intraparticle diffusion did not play a key role in the entire adsorption process. The process of cephalomannine adsorption onto Sylopute was exothermic and spontaneous. In addition, the isosteric heat of adsorption was constant even with variation in surface loading indicating homogeneous surface coverage.

• Korean Journal of Pharmacognosy
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• v.26 no.2
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• pp.116-121
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• 1995

To seek for a stable supply source of taxol as an anticancer agent urgently needed for the treatment of ovarian cancer, the concentrations of taxol and cephalomannine in bark and needles of 37 yew (Taxus cuspidata S. et Z.) trees grown in 6 locations of Cheju Island were analyzed by using HPLC. A considerable variation in the content was observed in plant part and the location. The average taxol content in the needles ($220.3{\;}{\pm}{\;}56{\;}{\mu}g$ per g dry wt) was ca. 4 times hgher than that in the bark, whereas the content of cephalomannine in the needles $(353{\;}{\pm}{\;}141{\;}{\mu}g)$ was ca. 5 times higher than that in the bark. Particularly, even within Cheju Island, needles from trees grown near the coast including Sogwipo area contained much higher taxol contents than needles from trees grown at mountain locations, indicating that taxane level is affected by environmental effects. Taxol in the needles was confirmed by electrospray mass spectrometry. These results suggest that the needles of yew trees growing in Cheju Island may provide a renewable source for taxol.

• Applied Chemistry for Engineering
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• v.8 no.2
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• pp.286-291
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• 1997

Taxol which is recognized as a powerful anticancer reagent was extracted from yew extract and separated by NP-HPLC (Normal-PhaseHigh Performance Liquid Chromatography). The experiments were performed in the isocratic mode with $5{\mu}l$ to $100{\mu}l$ injection volume and 1ml/min mobile phase flow rate. The major mobile phase was hexane and small amounts of ethanol, methanol, 1-propanol and isopropanol were added to change the retention behavior. Prior to a real sample, the artificial mixture of taxol, cephalomannine and 10-deacetyltaxol was tested. They are hard to be separated because of similar chemical structures. The experimental results showed that the proper composition of mobile phase for separating the three components was found 96% hexane and 4% ethanol(vol.%) or 96% hexane, 2% 1-propanol and 2% methanol(vol.%). Compared to the run time of 80 minutes for the binary system, the mixture was separated within 50 minutes with the less amount of mobile phase for the ternary system. Finally, $1{\mu}g$ of taxol was separated from yew tree extracts under the optimum operating conditions.

• KSBB Journal
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• v.11 no.3
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• pp.323-328
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• 1996

Effects of three kinds of precursors as well as exogenous taxanes on the production of taxol and its derivatives were investigated in Taxus cuspidata and Taxus brevifolia cell suspension cultures. When geraniol was added as a precursor of geranylgeranyl pyrophosphate to enhance diterpenoid metabolism, production of some taxanes including taxol was enhanced. The time of addition and amount of feeding were found to be important factors. Feeding of camphor and menthol resulted in negative effects on taxol production. Influences of exogenous taxanes on taxane production by cell cultures were found to be very complicated. When taxol, baccatin III, cephalomannine were exogenously added into the culture, production of baccatin III, 7-epi-10-deacetyltaxol, 10-deacetyltaxol was increased respectively.

• Journal of Microbiology and Biotechnology
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• v.27 no.8
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• pp.1379-1385
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• 2017

The content of taxol in the bark of yews is very low, and this is not affordable from the environmental point of view. Thus, it is a necessity to look for alternative sources of taxol production to solve its supply. Currently, a large portion of the taxol in the market comes from chemical semi-synthesis, but the semi-synthetic precursors such as baccatin III and 10-deacetyl-baccatin III are extracted from needles and twigs of yew trees. Taxol-producing fungi as a renewable resource is a very promising way to increase the scale of taxol production. Our group has obtained a taxol-producing endophytic fungus, Aspergillus niger subsp. taxi HD86-9, to examine if A. niger can produce the taxanes. Six compounds from the fermentation broth of strain HD86-9 were isolated and identified by $^1H$ NMR, $^{13}C$ NMR, and ESI-MS. The results showed that the six compounds included four taxane diterpenoids (taxol, cephalomannine, baccatin III, and 10-deacetyl-baccatin III) and two non-taxane compounds (${\beta}-sitosterol$ and flavonoid isovitexin). The study verified that the taxanes can be produced by the A. niger, which is very important to taxol production via chemical semi-synthesis. Additionally, the finding is potentially very significant to solve the taxol semi-synthetic precursors extracted from needles and twigs of yew trees, and the precursor production can be easily increased through the culture condition optimization, genetic breeding, and metabolic engineering of the A. niger.

• KSBB Journal
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• v.9 no.2
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• pp.186-190
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• 1994

The content of taxol and related compounds in various tissues of native yews( T. cuspidata var. latifolia) grown in 5 locations of Ullung Island were analyzed. A considerable range of vanation in the content was observed in the needle and bark collected from different trees located at the same area as well as at five different areas. Taxol content was much higher in the needle(0.017% on the dry weight basis) than those in the bark, whereas the content of 10-deacetyl baccatin III(10-DAB III) was slightly higher in the bark(0.073%), regardless of the location of the trees collected. Particuayly, the needle collected from the Hyunpo area, which located in North-west part of Ullung Island, contained the highest level of taxol(0.024%) exceeding the reported level in dried barks of Pacific yew and also somewhat higher level of its Precusor, 10-DAB III(0.049%). These results suggested that the needle of the yew at the Ullung Island could be suitable materials as a renewable source for the mass production of taxol.

• KSBB Journal
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• v.15 no.5
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• pp.537-540
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• 2000

In developing a HPLC purification process, it was hoped that a single chromatographic system would be sufficient to abtain pure paclitaxel in high yield. However, no such system was found, due in part to the complex taxoid profile of crude paclitaxel and to the rigorous nature of the product specification. A two step HPLC purification was adopted using reverse-phase separation on C(sub)18 as a first step, and normal-phase separation on silica as the final polishing step. Impurity profiles were established and maintained for paclitaxel, which identified and quantified each impurity observed in purified paclitaxel from these two steps, all impurities at or above 0.1% were identified. Results provide information for improving the quality control of paclitaxel production.