Taxol Content Research Articles

Variation in content of taxol and related taxanes in Eastern Himalayan populations of Taxus wallichiana.

Extraction and analysis of paclitaxel and other taxanes in bark, needle leaves and stem segments of male and female plants of Taxus wallichiana, representing several populations, indicate that significant variation in taxane content exists within the population. Bark accumulated maximum amount of paclitaxel in almost all plants. Populations located at higher altitude tended to accumulate more paclitaxel than lower altitude plants. Seasons in which samples were collected and plant age have also been shown to affect paclitaxel accumulation. No effects of plant sex on paclitaxel content of the plants analyzed were observed. Significant differences in baccatin-III and 10-deacetylbaccatin III content were found to exist in the trees analyzed in this study.

Taxol content in the bark of Himalayan Yew in relation to tree age and sex

Taxol content in the bark of Taxus baccata trees growing in a homogenous (uniform) environment at Jageshwar, District Almora in Central Himalaya has been quantified. The average taxol concentration in the bark of sampled trees was 0.0558±0.008% (of dry wt.) and was about 64% higher for male plants (averaged across tree age) in comparison to female trees. Maximum taxol content was recorded in the bark samples collected from trees of >110 yrs age. ANOVA indicates a significant difference in the taxol content of bark from trees of different ages, however, differences were not significant between sexes. Taxol was quantified by HPLC using a standard curve prepared with authentic taxol; the identification of bark taxol was confirmed by UV and mass spectrometry. The total taxol content of the bark of Taxus trees across an age series was found to range between 0.064 to 8.032 g/tree, and a tree of about 100 yrs age can yield 5.74 kg dry bark.

Effect of the season of explant collection on the diterpenoid taxol content in Taxus baccata L. callus tissue.

Effect of the season of explant collection on the diterpenoid taxol content in Taxus baccata L. callus tissue.

RECOVERY OF TAXOL FROM THE EXTRACT OF TAXUS CUSPIDATE CALLUS CULTURES WITH AL2O3 CHROMATOGRAPHY

In this study, we reported a chromatographic protocol using C18 silica gel phase and basic Al2O3 phase to research the creating and recovery of taxol from the extract of Taxus cuspidate callus cultures. With the cleaning up by basic Al2O3 chromatography, the content of taxol determined in our experiment was increased greatly. The main source of increasing taxol concentration was the isomerization of 7-epi-taxol to taxol; taxol could also be decomposed to baccatin III and 10-deacetylbaccatin III in the Al2O3 column. At the optimized conditions, the total recovery of taxol from the extract was more than 160%.

The Effect of Plant Age on Taxane Content of Cultivated Taxus

ABSTRACT The relative content of taxol and taxanes in rooted cuttings (˜ 1 year old), liner (3–4 years old), and landscape-size (7–8 years old) Taxus plants was investigated. Leaves contained a higher concentration of paclitaxel and taxanes than other plant tissues. The concentration of taxanes in the stems was relatively small and resulted in dilution of the taxanes in the whole plant biomass of liner and landscape-size plants. The small size of rooted cuttings (average dry weight = 0.94 g/plant) and liners (average dry weight = 39 g/plant) meant separation of leaves from stems and roots would not be practical. For the rooted cuttings, no substantial reduction in the paclitaxel/taxanes concentration resulted from extracting the whole plants versus leaves.

Adsorption characteristics and separation of taxol from yew tree by NP-HPLC

Abstract Taxol (Paclitaxel) is a powerful anticancer produced by the pacific yew. Taxol shows promise for the treatment of a variety of human cancers, including leukemia and certain ovarian, breast and lung tumors. Industries and governmental research institutes have actively studied to produce highly pure taxol on a commercial scale. In this work, the separation of taxol from yew tree was studied with solvent extraction and normal phase liquid chromatography (NP-HPLC). The content of taxol in the tree was found to be 0.064 mg/g of dry powder. The solvent used in extraction was methanol and the extract was concentrated by the partition of water and methylene chloride. Impurities were removed in the pretreatment step with open column, where silica packings (10–40 μm, YMC) were packed. In this step, the first mobile phase was methylene chloride/acetone, 97/3 vol.% and the second mobile phase methylene chloride/acetone, 75/25 vol.%. The sample was further separated by varying the composition of solvent, flow rate, and injection amount in analytical chromatography. Also experiments were performed to obtain the correlation equation between the optimum resolution and the mobile phase composition. The experimental resolution of cephalomannine/taxol was 1.81 and that of taxol/10-deaccetyltaxol was 5.43. The values calculated from the correlation equation were 2.32 and 6.32, respectively, and in good agreement with the experimental values. In the column (3.9×300 mm) with larger particle sizes (Lichrospher Si 60, 15 μm), the mobile phase composition was hexane/2-propanol/MeOH, 90/4/6 vol.% in isocratic mode. At 1.5 ml/min of mobile phase flow rate, 2.58 μg of taxol was collected in the experimental conditions. The purified taxol was used to determine the adsorption isotherm of taxol. From the experimental results, the adsorption isotherm was obtained as the following Langmuir type. C S = 59.5C M 1+2.0C M To obtain the adsorption isotherm, only two injections of small and large amount of taxol were required and the Langmuir adsorption parameters were calculated from the assumption of the monolayer coverage on the solid surface. Analytical experimental conditions were extended to preparative liquid chromatography. In preparative column (22×250 mm) packed by the same packing with the same mobile phase composition, at 16 ml/min 2.41 mg of taxol was purified in the single run.

Single step Al2O3 chromatography for improved separation and recovery of Taxol

An improved method that uses a single alkaline Al2O3 chromatography step was developed both for separating Taxol from the extracts of Taxus cuspidate callus cultures, and meanwhile converting other taxanes to Taxol catalyzed by the Al2O3 adsorbent. Under the optimized operating conditions, a Taxol recovery of 170% was obtained. The final Taxol content was 29% starting from less than 1% in the initial extracts.

PREPARATIVE CHROMATOGRAPHIC SEPARATION OF TAXOL FROM YEW TREES

Taxol shows promise for the treatment of a variety of human cancers, including leukemia and certain ovarian, breast, and lung tumors. In this work, the separation of taxol from Korean Yew tree was studied with solvent extraction and liquid chromatography. The content of taxol in the tree was analyzed to be 0.064 mg/g of dry powder. Methanol was used to extract taxol and the resulting extract was concentrated by the partition of water and methylene chloride. In the pretreatment step with open tubular chromatography, the first mobile phase was methylene chloride/acetone, 97/3 vol. % and the second mobile phase methylene chloride/acetone, 75/25 vol. %. The sample containing taxol was further purified by varying the composition of solvent, flow rate, and injection amount in analytical chromatography. In a semi-preparative column (3.9×300 mm) with larger particle sizes the mobile phase composition was hexane/2-propanol/methanol, 90/4/6 vol.% in isocratic mode. Based on the mobile phase composition with 16 mL/min of mobile phase flow rate in a preparative column (22×250 mm), 2.41 mg of purified taxol was obtained in a single run.

Taxol content in the storage samples of the needles of Himalayan Taxus baccata and their extracts.

Taxol content in the storage samples of the needles of Himalayan Taxus baccata and their extracts.

Efficient selection of cells with high taxol content from heterogeneous Taxus cell suspensions by magnetic or fluorescent antibodies : Michio Kawamura1,3∗, Takeo Shigeoka1, Makoto Tahara2,4, Masamichi Takami2, Hiroaki Ohashi2,5, Motomu Akita1,6, Yoshinori Kobayashi1, Tetsuo Sakamoto2, ( Tsukuba Research Laboratories, Kyowa Hakko Kogyo Co. Ltd., 2 Miyukigaoka, Tsukuba, Ibaraki 305-0841 1; Life Science Research Center, Nippon Steel Corporation, 1618 Ida, Nakahara-ku,

Efficient selection of cells with high taxol content from heterogeneous Taxus cell suspensions by magnetic or fluorescent antibodies : Michio Kawamura1,3∗, Takeo Shigeoka1, Makoto Tahara2,4, Masamichi Takami2, Hiroaki Ohashi2,5, Motomu Akita1,6, Yoshinori Kobayashi1, Tetsuo Sakamoto2, ( Tsukuba Research Laboratories, Kyowa Hakko Kogyo Co. Ltd., 2 Miyukigaoka, Tsukuba, Ibaraki 305-0841 1; Life Science Research Center, Nippon Steel Corporation, 1618 Ida, Nakahara-ku,

Enhanced production of taxol in suspension cultures of Taxus chinensis by controlling inoculum size

Inoculum size (1.5Ð6.0 g dry weight/l) signiÞcantly affected cell growth and accumulation of intracellular and extracellular taxol in Taxus chinensis. A shorter cultivation time and a higher biomass productivity were achieved using inoculum size of 6.0 g DW/l. Both the intracellular content and total production of taxol were increased almost 30% with an increase of inoculum size from 1.5 to 3.0 g DW/l, while an even higher inoculum size decreased taxol formation. The extracellular taxol concentration was relatively higher (0.091 mg/l) at low inoculum sizes of 1.5 and 2.0 g DW/l; and in various cases it was less than 25% of the total amount of taxol produced.

Proliferative activity of callus cultures of Taxus baccata L. in relation to anticancer diterpenoid taxol biosynthesis

Stable growing callus cultures were recovered from stem segments of Taxus baccata. Callus developed from the peridermal cells. The content of taxol in callus tissues varied in the range of [0.0003–0.001% on dry weight basis] and was higher in fast growing calli compared to slow growing calli.

Effects of plant growth regulators applied to the roots of hydroponically grown Taxus × media plants on the production of taxol and related taxanes

Taxus × media cultivars/varieties ( n = 14) (purchased from Heasley's Nurseries, Butler, Pennsylvania) were screened for taxol, cephalomannine, and 10-deacetyltaxol content in their needles and roots. Overall, the mature roots of cv. Hicksii and var. Number 8 had the highest levels of taxol (424 and 427 mg/kg dry weight, respectively), while in the needles, the highest amounts were found in cv. Fieldii and var. Number 8 (231 and 249 mg/kg dry weight, respectively). Treating hydroponically grown cv. Hicksii plants with 100 μM gibberellic acid (GA) or 1000 μM chlorocholine chloride (CCC) decreased root growth by approximately 38, and 22%, respectively, while treating with 100 μM CCC increased root growth by 22%, compared to control plants. However, none of the treatments resulted in a greater than 9% increase in shoot growth compared to control plants, when evaluated over a 24 week period. Overall, the 100 μM CCC treatment promoted the highest root mass, root-to-shoot ratio, growth index, root volume, average root diameter, and total root length. The roots of plants treated with 1000 μM CCC and 10 μM ANC exhibited the highest amount of taxol, 332 ± 32 and 334 ± 34 mg/kg on a dry weight basis, respectively, compared to control plants (195 ± 32 mg/kg). However, none of the treatments had dramatic effects on the amount of taxol, cephalomannine, or 10-deacetyltaxol in needle and bark samples. In order to evaluate the overall effect of these treatments, the concentration of taxol, cephalomannine, and 10-deacetyltaxol found in the roots need to be expressed as a function of concentration and total root mass, because the different treatments significantly affected only root growth. Accordingly, the highest amounts were found in the roots of the plants treated with 100 μM CCC (430 μg per plant, compared to 308 μg per control plant). This increase merely represents the increased root growth observed with the 100 μM CCC treatment. CCC seems to have enhanced the process of secondary growth in the roots, as shown in scanning electron micrographs. Since the roots of plants treated with 100 and 1000 μM CCC contained higher concentrations of taxol, it appears that the process of secondary growth was responsible for the increase in taxol content.

Determination of taxol in Taxus species grown in Hungary by high-performance liquid chromatography-diode array detection effect of vegetative period

The influence of a vegetative period on the taxol content in the needles of Taxus brevifolia grown in Hungary was determined using porous graphitized carbon column and a HPLC-diode array detection system. The relative standard deviation of the retention time of taxol peak was 1.24%, the peak symmetry 1.06–1.07 indicating the reliability of the HPLC systems. It was found that the accuracy of the peak purity test can be enhanced by carrying out the test at various wavelengths. It was established that the taxol content is considerably higher in the winter months and taqxol is purer in the same period. Taxol content also depends on the production site and taxol exctracted from the foliage contains more taxoteres than taxol extracted from bark.

Taxol content of various Taxus species in Hungary

The anticancer drug taxol was separated and quantitatively determined in bark and foliage of different Taxus species by high-performance liquid chromatography to prove the presence of taxol in Hungarian Taxus species. The measurements were carried out with photodiode array detection using a porous graphitized carbon column, and a water:dioxan 54:46 v/v eluent. Taxol was established as being present in measurable amounts in each Hungarian Taxus species. According to the results bark was richer in taxol than foliage. It could also be observed that the older the bark or foliage, the more taxol it contained. The validation process proved that the method is reliable and can be used for the separation and quantitative determination of taxol in both the bark and foliage of Taxus species grown in Hungary.

Pharmacokinetic study of taxol-loaded poly(lactic-co-glycolic acid) microspheres containing isopropyl myristate after targeted delivery to the lung in mice.

This study describes the pharmacokinetic behaviours of taxol after intravenous administration of taxol-loaded poly(lactic-co-glycolic acid) microspheres containing isopropyl myristate (namely, Taxol-IPM-PLGA-MS) and taxol saline solution to mice. Taxol-IPM-PLGA-MS were prepared using a solvent evaporation technique. The drug content and trapping efficiency of taxol in the microspheres were 5.09% (w/w) and 98%, respectively; the average diameter of the microspheres was 30.1 microns. Scanning electron microscopy showed that Taxol-IPM-PLGA-MS were spherical with a smooth surface. After administration of the drug saline solution (3 mg taxol/kg), taxol disappeared rapidly from plasma within 4-6 h and distributed extensively in various tissues. The tissue levels and AUCfinite of taxol in the lung were obviously higher than those in plasma but relatively lower than those in kidneys, bile, and liver. The biodistribution of taxol after administration of Taxol-IPM-PLGA-MS (3 mg taxol/kg), on the other hand, was altered significantly from the control (taxol solution) group. No taxol was detected in plasma or bile within 3 weeks, and only very low level of taxol was detected in the kidneys or liver within 48 h. However, taxol concentrations in the lung were increased significantly with the microsphere group; the peak concentration of taxol and AUCfinite in the lung was three times and 500 times higher than those with the taxol solution group, respectively. It was also noticed that the taxol levels in the lung were maintained at relatively high levels (> 10 micrograms/ml) for 3 weeks. Thus, the present study demonstrated the effective targeted delivery of taxol to the lung of mice using Taxol-IPM-PLGA-MS.

Taxol content in the seeds of Taxus SPP.

The concentrations of taxol and related compounds in the mature dried seeds of several Taxus species were determined by HPLC. In addition, the taxol level of the seeds of T. cuspidata at different stages of maturation was studied. The variation in the taxane content was dependent on individual trees within species as well as among species. The average contents of taxol and its precursor, 10-deacetyl baccatin III (10-DAB III) in the mature seeds of different species were 67.3 ± 50 and 96.2 ± 83 μg g −1 dry wt, respectively. In mature seed parts of T. cuspidata var. latifolia obtained from tree U5, the embryo weight was ca 0.2% of that of the dry weight of the whole seed and contained the highest level of taxol (894 μg g −1) when compared with that obtained for the endosperm (23 μg g −1) and testa (376 μg g −1). However, the taxol content per seed was highest in the testa (20.5 μg) followed by the endosperm (0.75 μg) and embryo (0.18 μg). The taxol content of the fresh seed reached a maximum of 332 μg g −1 and 20 μg seed −1 at the middle stage of seed maturation and then decreased with further maturation. The taxol identification in the seed was confirmed by electrospray mass spectrometry.

Stepwise gradient thin-layer chromatography and densitometric determination of taxol in extracts from various species ofTaxus

Extracts fromTaxus species needles (T. media, T. baccata, T. cuspidata) were separated on thin layers of silica Si 60 by two-stage development (first stage: 60 % heptane solution of a mixture of 5% methanol and 95% chloroform; second stage: 70% heptane solution of the same solution of methanol in chloroform). The peak of taxol was satisfactorily separated from the neighbouring peaks to permit its densitometric determination. Content of taxol for various samples of Taxus species is compared.

Effect of Drying Taxus Needles on their Taxol Content: The Impact of Drying Intact Clippings

Evaluation of various methods of drying yew (Taxus) biomass was accomplished. The effect of the separation of the needles from clippings on the taxol content of Taxus plants was noted. Drying clippings intact preserves their taxol content.

Taxol and Related Compounds in Korean Native Yews (Taxus cuspidata)

The concentrations of taxol and related compounds in the bark and needles of Taxus cuspidata grown on Mt. Jiri, Mt. Sobaek, and Cheju Island, and T. cuspidata var. latifolia on Ullung Island in Korea were determined by high performance liquid chromatography (HPLC). The taxane content significantly varied with the location and plant part. The taxol content in the bark of native yews from Mt. Jiri and Mt. Sobaek was high when compared to that reported for Pacific yew (T. brevifolia), whereas bark from trees on Cheju and Ullung islands contained a much lower level. Surprisingly, the needles from Cheju and Ullung islands contained a much higher level of taxol (0.022% and 0.0173%, respectively) than those of intermountain locations (0.0058% to 0.0085%), on the basis of dry weight. The bark and needles of T. cuspidata var. latifolia on Ullung Island also contained relatively high concentrations of 10-deacetylbaccatin III, 0.0497% and 0.0545%, respectively, and indicated that environmental factors may affect the quantity. Taxol in the needles was confirmed by electrospray mass spectrometry. These results suggest that foliage from yew trees growing in their natural habitats on Cheju and Ullung islands may provide a renewable source for taxol.