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1.
Taxol production during the cultivation on a modified liquid and potato dextrose broth medium was indicated for the first time to occur in Phyllosticta spinarum, an endophytic fungus isolated from the needles of Cupressus sp. The presence of taxol in the fungal culture filtrate was confirmed by chromatographic and spectroscopic methods of analysis. The amount of taxol produced by this fungus was quantified by high performance liquid chromatography. The maximum amount of taxol production was obtained in this fungus when grown on M1D medium (235 μg/L) followed by PDB medium (125 μg/L). The results indicate that P. spinarum is an excellent candidate for taxol production . The production rate was 4.7 × 103‐fold higher than that found in the culture broth of an earlier reported fungus, Taxomyces andreanae. The fungal taxol extracted also showed a strong cytotoxic activity in the in vitro culture of human cancer cells tested in an apoptotic assay.  相似文献   

2.
Phyllosticta tabernaemontanae, a leaf spot fungus isolated from the diseased leaves of Wrightia tinctoria, showed the production of taxol, an anticancer drug, on modified liquid medium (MID) and potato dextrose broth (PDB) medium in culture for the first time. The presence of taxol was confirmed by spectroscopic and chromatographic methods of analysis. The amount of taxol produced by this fungus was quantified using high performance liquid chromatography (HPLC). The maximum amount of taxol production was recorded in the fungus grown on MID medium (461 μg/L) followed by PDB medium (150 μg/L). The production rate was increased to 9.2 × 103 fold than that found in the culture broth of earlier reported fungus, Taxomyces andreanae. The results designate that P. tabernaemontanae is an excellent candidate for taxol production. The fungal taxol extracted also showed a strong cytotoxic activity in the in vitro culture of tested human cancer cells by apoptotic assay.  相似文献   

3.
The fungus Colletotrichum capsici was isolated from the diseased fruits of Chilli plant, Capsicum annuum. The isolated test fungus was identified by its morphological and molecular characteristic features. For the first time, the fungus was screened for the production of taxol on modified liquid medium. The presence of taxol was confirmed by the spectroscopic and chromatographic methods of analyses. The amount of taxol produced by this fungus was quantified by HPLC. The maximum amount of fungal taxol production was recorded as 687 μg/L. The production rate was 13 740‐fold higher than that, previously reported for the fungus Taxomyces andreanae. The extracted fungal taxol showed a strong cytotoxic activity in an in vitro culture of human cancer cells indicating that the increase in taxol concentration induces increased cell death. A PCR‐based screening for taxadiene synthase (ts), a unique gene in the formation of the taxane skeleton, confirmed the molecular blueprint for taxol biosynthesis. The results show that the fungus C. capsici is an excellent candidate for an alternate source of taxol supply and can serve as a potential species for genetic engineering to enhance the production of taxol to a higher level.  相似文献   

4.
Taxol is a highly functionalized anticancer drug widely used in hospitals and clinics. The leaf spot fungus, Phyllosticta dioscoreae was isolated from diseased leaves of Hibiscus rosa-sinensis and screened for extracellular production of taxol in M1D (Modified liquid medium) and PDB (Potato dextrose broth) medium for the first time. The fungus was identified by its morphological and conidial features in the culture growth. The presence of taxol in the fungal culture filtrate was confirmed by different spectroscopic and chromatographic analyses. The amount of taxol produced was quantified by HPLC. The maximum amount of taxol produced was found to be 298 μg/L in M1D medium. Production rate was 5.96 × 103 times faster than that found in culture broth of earlier reported fungus, Taxomyces andreanae. The extracted fungal taxol also showed strong cytotoxic activity in vitro in the cultures of human cancer cells tested by apoptotic assay. The results indicate that P. dioscoreae is an excellent source of taxol production, which suggests that the fungus has potential to undergo genetic engineering in order to improve its production level.  相似文献   

5.
Variations of pigment content in the microscopic conchocelis stage of four Alaskan Porphyra species were investigated in response to environmental variables. Conchocelis filaments were cultured under varying conditions of irradiance and nutrient concentrations for up to 60 d at 11°C and 30 psu salinity. Results indicate that conchocelis filaments contain relatively high concentrations of phycobilins under optimal culture conditions. Phycobilin pigment production was significantly affected by irradiance, nutrient concentration, and culture duration. For Porphyra abbottiae V. Krishnam., Porphyra sp., and Porphyra torta V. Krishnam., maximal phycoerythrin (63.2–95.1 mg · g dwt?1) and phycocyanin (28.8–64.8 mg · g dwt?1) content generally occurred at 10 μmol photons · m?2 · s?1, f/4–f/2 nutrient concentration after 10–20 d of culture. Whereas for Porphyra hiberna S. C. Lindstrom et K. M. Cole, the highest phycoerythrin (73.3 mg · g dwt?1) and phycocyanin (70.2 mg · g dwt?1) content occurred at 10 μmol photons · m?2 · s?1, f nutrient concentration after 60 d in culture. Under similar conditions, the different species showed significant differences in pigment content. P. abbottiae had higher phycoerythrin content than the other three species, and P. hiberna had the highest phycocyanin content. P. torta had the lowest phycobilin content.  相似文献   

6.
Taxol is an important anticancer drug widely used in the clinic. An endophytic fungus Bartalinia robillardoides (strain AMB-9) was isolated from Aegle marmelos, a medicinal plant and screened for taxol production. The fungus was identified based on the morphology of the fungal culture and the characteristics of the spores. This fungus was grown in MID liquid medium and analyzed chromatographically and spectrometrically, for the presence of Taxol. The amount of taxol produced by this endophytic fungus was quantified by HPLC. It produced 187.6 μg/L of taxol which suggests that the fungus can serve as a potential material for genetic engineering to improve the production of Taxol. This fungal taxol isolated from the organic extract of this fungal culture, has strong cytotoxic activity towards BT 220, H116, Int 407, HL 251 and HLK 210 human cancer cells in vitro, tested by Apoptotic assay.  相似文献   

7.
The optimization of taxol production by Fusarium redolens by one factor at a time (OFAT) approach led to production of 70 μg/L of taxol. With sucrose and NH4NO3 as the carbon and nitrogen sources and medium volume (V m ) to flask volume (V f ) ratio of 0.2, a greater taxol production was attained. NH4NO3, MgSO4?7H2O and NaOAc at 6.25, 0.63, and 1.25 g/L, were the significant factors for attaining the highest taxol production. The optimization of culture variables led to the production of taxol from 66 to 198 μg/L, which is three fold higher than that in the unoptimized medium. Current study results suggested the success of Response Surface Methodology in enhancing the production of fungal taxol.  相似文献   

8.
1. Beaver Lake, a large epishelf lake in eastern Antarctica was sampled on two occasions during the austral summer of 2000. Two sites, one 1 km offshore and another 6 km offshore were sampled at intervals to depths of 40 and 110 m, respectively. 2. The lake is an end member of ultra‐oligotrophic lake systems with a very low carbon pool. Dissolved organic carbon concentrations ranged between 95 and 652 μg L–1. Nutrient levels were generally low with soluble reactive phosphorus ranging from undetectable to 8.4 μg L–1, ammonium ranged between 1.8 and 5.0 μg L–1, nitrate from undetectable to 161 μg L–1 and nitrite 1.1–5.3 μg L–1. 3. Chlorophyll a concentrations (0.39–4.38 μg L–1) showed an unusual distribution with the highest levels close to the lake bottom at the offshore site (110 m) where the phototrophic nanoflagellates (PNAN) displayed strong autofluorescence. 4. Bacterial concentrations were low, with a maximum of 7.60 × 107 L–1, as were the concentrations of heterotrophic nanoflagellates that exploit them. 5. Primary production ranged between 19.7 and 25.49 μg C L–1 day–1 and bacterial production from 0.32 to 1.15 μg C L–1 day–1. 6. In common with other continental Antarctic lakes, the system was dominated by a microbial plankton. However, a dwarf variety of the calanoid copepod, Boeckella poppei, occurred below 25 m at concentrations of 3–5 L–1. 7. The data suggest that primary production and bacterial production were not limited by nutrient availability, but by other factors, e.g. in the case of bacterial production by organic carbon concentrations and primary production by low temperatures.  相似文献   

9.
A new microbial cyclic dipeptide (diketopiperazine), cyclo(d ‐Tyr‐d ‐Phe) was isolated for the first time from the ethyl acetate extract of fermented modified nutrient broth of Bacillus sp. N strain associated with rhabditid Entomopathogenic nematode. Antibacterial activity of the compound was determined by minimum inhibitory concentration and agar disc diffusion method against medically important bacteria and the compound recorded significant antibacterial against test bacteria. Highest activity was recorded against Staphylococcus epidermis (1 µg/ml) followed by Proteus mirabilis (2 µg/ml). The activity of cyclo(d ‐Tyr‐d ‐Phe) against S. epidermis is better than chloramphenicol, the standard antibiotics. Cyclo(d ‐Tyr‐d ‐Phe) recorded significant antitumor activity against A549 cells (IC50 value: 10 μM) and this compound recorded no cytotoxicity against factor signaling normal fibroblast cells up to 100 μM. Cyclo(d ‐Tyr‐d ‐Phe) induced significant morphological changes and DNA fragmentation associated with apoptosis in A549 cells. Acridine orange/ethidium bromide stained cells indicated apoptosis induction by cyclo(d ‐Tyr‐d ‐Phe). Flow cytometry analysis showed that the cyclo(d ‐Tyr‐d ‐Phe) did not induce cell cycle arrest. Effector molecule of apoptosis such as caspase‐3 was found activated in treated cells, suggesting apoptosis as the main mode of cell death. Antioxidant activity was evaluated by free radical scavenging and reducing power activity, and the compound recorded significant antioxidant activity. The free radical scavenging activity of cyclo(d ‐Tyr‐d ‐Phe) is almost equal to that of butylated hydroxyanisole, the standard antioxidant agent. We also compared the biological activity of natural cyclo(d ‐Tyr‐d ‐Phe) with synthetic cyclo(d ‐Tyr‐d ‐Phe) and cyclo(l ‐Tyr‐l ‐Phe). Natural and synthetic cyclo(d ‐Tyr‐d ‐Phe) recorded similar pattern of activity. Although synthetic cyclo(l ‐Tyr‐l ‐Phe) recorded lower activity. But in the case of reducing power activity, synthetic cyclo(l ‐Tyr‐l ‐Phe) recorded significant activity than natural and synthetic cyclo(d ‐Tyr‐d ‐Phe). The results of the present study reveals that cyclo(d ‐Tyr‐d ‐Phe) is more bioactive than cyclo(l ‐Tyr‐l ‐Phe). To the best of our knowledge, this is the first time that cyclo(d ‐Tyr‐d ‐Phe) has been isolated from microbial natural source and also the antibacterial, anticancer, and antioxidant activity of cyclo(d ‐Tyr‐d ‐Phe) is also reported for the first time. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   

10.
11.
Taxus globosa is the only species of the Taxus genus that grows in Mexico. In this study, callus cultures from leaves and young shoots of T. globosa were established in Gamborg’s B5 medium supplemented with 2,4-dichlorophenoxiacetic acid (2 mg/L), kinetin (0.5 mg/L) and gibberellic acid (0.25 mg/L). Callus growth and taxane production were evaluated using two culture media: Woody Plant Medium and Gamborg’s B5 supplemented with picloram (2 mg/L), kinetin (0.1 mg/L) and gibberellic acid (0.5 mg/L). The effect of the inoculum size (50, 100 and 150 g FW/L) and culture media (Woody Plant Medium and Gamborg’s B5) with and without the presence of methyl jasmonate (100 μM) on T. globosa cell suspensions was assessed. Taxane analysis revealed that the calli in Gamborg’s B5 produced taxol (50 μg/g DW), baccatin III, 10-deacetyl baccatin III and 10-deacetyl taxol. Woody Plant Medium also induced the production of taxol, although to a lesser extent. The optimum inoculum size was 50 g FW/L. In cell suspension cultures, both media had a significant effect on taxane production when supplemented with methyl jasmonate. In Woody Plant Medium, at day 14, a total concentration of 197.999 μg/L of taxol, 160.622 μg/L of baccatin III, 633.724 μg/L of 10-deacetyl baccatin III and 229.611 μg/L 10-deacetyl taxol were obtained, with total excretion of baccatin III and 10-deacetyl taxol to the culture medium. In Gamborg’s B5, cephalomanine was obtained at a concentration of 91.428 μg/L without elicitation, and all taxanes were excreted to the medium to a variable extent.  相似文献   

12.
Taxol production in suspension cultures of Taxus baccata   总被引:18,自引:0,他引:18  
The response of Taxus baccata (PC2) to basic manipulations of culture conditions is described. Suspension cultures of Taxus baccata (PC2) were maintained at 25°C on a modified B5 medium with two-week transfers. Under these conditions, no taxol® is formed. However, if the cells are left in the same medium for 7 or more additional days, taxol is produced and released (ca. 90%) into the extracellular medium. Levels as high as 13 mg 1–1 extracellular taxol were achieved in shake flask cultures and taxol was the primary taxane formed representing between 50 and 80% of total taxane in the medium. The cells are sensitive to changes in culture conditions and cultures cycle through periods of high (13 mg 1–1) and low (<0.1 mg 1–1) levels of taxol production during extended culture. Picloram was the most effective of the auxins tested with respect to cell growth but it suppressed taxol production. Addition of fructose to moderately-productive cultures (ca. 4 mg 1–1) improved taxol production, but cultures in a high producing state did not respond. Glucose suppressed taxane production. Two isoprenoids (geraniol and pinene) had a modest effect on taxol production when added to cultures at 10 mg 1–1.®|Taxol is a registered trademark of Bristol Meyer Squibb for paclitaxel  相似文献   

13.
14.
Aspergillus niger hyphae were found to grow with unliquefied potato starch under aerobic conditions, but did not grow under anaerobic conditions. The raw culture ofA. niger catalyzed saccharification of potato starch to glucose, producing approximately 12 g glucose/L/day/ The extracellular enzyme activity was decreased in proportion to incubation time, and approximately 64% of initial activity was maintained after 3 days. At 50°C,A. niger hyphae growth stopped, while the extracellular enzyme activity peaked. On the basis of theA. niger growth property and enzyme activity, we designed a serial bioreactor system composed of four different reactors. Fungal hyphae were cultivated in reactor I at 30°C, uniquefied starch was saccharified to glycose by a fungal hyphae culture in reactors II and III at 50°C, and glucose was fermented to ethanol bySaccharomyces cerevisiae in reactor IV. The total glucose produced by fungal hyphae in reactor I and saccharification in reactor II was about 42 g/L/day. Ethanol production in reactor IV was approximately 22 g/L/day, which corresponds to about 79% of the theoretical maximum produced from 55 g starch/L/day.  相似文献   

15.
16.
Abstract Six-day-old larvae of the catarina scallop, Argopecten ventricosus (=circularis), were infected with different concentrations of Vibrio alginolyticus to determine virulence and to describe vibriosis in this species. The development of vibriosis was compared to the effect of the supernatant of a 24-h V. alginolyticus culture. An experimental larvae culture system (ELCS) yielded a maximum survival of 80% from the 6th to the 19th day (control and low concentrations of V. alginolyticus). No effect was shown with concentrations of V. alginolyticus below 0.5 × 105 CFU ml−1. At concentrations higher than 5.0 × 105 CFU ml−1, swimming depletion, empty stomachs, lipidic granules in the digestive system, velum degradation, and massive mortality were observed. The supernatant of V. alginolyticus culture showed similar effects to the highest concentrations of V. alginolyticus cells. Received: 13 November 1996; Accepted 28 March 1997  相似文献   

17.
The influence of inoculum size on aflatoxin B1 (AFB1), zearalenone (ZEN) and deoxynivalenol (DON) production was examined on irradiated corn kernels. Spore concentrations were determined in serial dilutions and adjusted to 10,102,103,105 and 106 spores/ml. Aflatoxin B1 production was dependent on the inoculum size. The high levels of aflatoxin B1 produced byA. parasiticus (21 and 30 mg/kg) were obtained with 102 and 103 spores/ml after 35 and 20 days incubation. There was no spore concentration influence on zearalenone and deoxynivalenol production after 10, 20 and 35 days incubation. At 28°C and 0.97 water activity (aw), the mean levels of zearalenone production were 382, 267 and 520 μg/kg and the mean levels on deoxynivalenol production were 697,465 and 782 μg/kg.  相似文献   

18.
Selenium, as an essential trace element, interferes through selenoproteins in many physiological processes of plants and mammals. Its antiviral activity has recently attracted much attention because selenium improves the antiviral capacity of animal cells against a few viruses relevant to human diseases. In this study, the red elemental selenium was purified from the fermentative culture of Herbaspirillum camelliae WT00C and then used to culture epithelioma papulosum cyprinid (EPC) cells or feed crucian carp and zebrafish. Finally, its antiviral effects were investigated at the cell level and living fishes after spring viraemia of carp virus infection. At the cell level, 5, 10 and 20 μg ml–1 red elemental selenium significantly induced the expression of interferon (IFN) and ISG15 genes in EPC cells. The viral TCID50 (50% tissue culture infective dose) values in the EPC cells incubated with 5, 10 and 20 μg ml–1 red elemental selenium were significantly less than those of the control. More expression of IFN and ISG15 genes and less TCID50 values indicate that red elemental selenium indeed improves the antiviral capability of EPC cells. In the crucian carp fed with the food containing 5 and 10 μg g–1 red elemental selenium, IFN expressions showed 13- and 39-fold increases at the 16th day of post-injection, and its expression was dependent on selenium concentrations. Meanwhile, no fish death occurred in all the experimental groups. In the zebrafish fed with the red worm containing 5 μg g–1 red elemental selenium, IFN and Mx expressions and survival rate were significantly higher than those of the control. The results of this study show that red elemental selenium indeed improves the antiviral activity of fish. The antiviral effects of selenium mainly come from its immune regulation through its incorporation into selenoproteins. The optimum level of selenium contributes to improving fish immunity, whereas excess selenium causes excessive immune and inflammatory responses.  相似文献   

19.
In the present research, the effect of indole‐3‐butyric acid (IBA) on the growth, and the production of some primary and secondary metabolites was studied in Nostoc linckia. In this respect, algae cultures were supplied with 0, 0.01, 0.1, 1, 10, and 100 μM IBA for 14 days. IBA at concentrations of 10 and 100 μM induced algal growth expressed as fresh weight in N. linckia. Treatment with IBA at all concentrations stimulated heterocyst formation. In addition, low concentrations of IBA (0.01, 0.1, and 1 μM) had a stimulatory effect on chlorophyll a and carotenoids accumulation. In contrast, higher concentrations of IBA induced the accumulation of phycocyanin, allophycocyanin, and phycoerythrin in the treated algae. In this case, IBA at the concentration of 10 μM was more effective. A significant decrease in protein content was observed in the algae treated by 0.01 μM IBA. All concentrations of IBA caused a decrease in sugar content, but lower concentrations were more effective. IBA application in all of the concentrations except 100 μM increased oligosaccharide‐linked mycosporine‐like amino acids (OS‐MAAs) content. Lower concentrations had a more significant effect on increasing OS‐MAAs content. However the concentrations of 10 and 100 μM IBA decreased scytonemin content. These results indicated the stimulatory impact of IBA on weight, heterocyst formation, and photosynthetic pigments in N. linckia.  相似文献   

20.
High concentrations of metals occur in some plant species (termed hyperaccumulators), such as the Ni hyperaccumulator Streptanthus polygaloides. We determined the tolerance of S. polygaloides to, and its accumulation abilities for, six metals (Ni, Zn, Cu, Co, Mn, and Pb). Potting mix concentrations used for all metals ranged from 0 to 1200 μg/g dry weight. For Ni, a treatment of 1600 μg/g was included. For Mn, treatments of 1600, 2000, and 2500 μg/g also were used, and for Pb these concentrations plus 3500 μg/g were included. Germination, plant number per pot, and size at days 30 and 39, number of plants at the end of the experiment (day 49), flower production, and metal concentration in the aboveground biomass were documented. Lead and Ni showed no consistent effects on plant performance, but yielded increased tissue metal concentrations. Streptanthus polygaloides was more sensitive to Co, Cu, and Zn, as ≥ 400 mg/g significantly suppressed plant growth, survival, and flower production. Tissue metal concentrations also were increased to maxima of 1500 μg Co/g, 120 μg Cu/g, and 6000 μg Zn/g. Manganese affected S. polygaloides less markedly, as ≥ 800 mg/kg decreased growth, survival, and flower production. Maximum tissue Mn concentration was 2900 μg/g. We concluded that S. polygaloides would be an appropriate phytoextractor for soils contaminated with Ni or low levels of Co but would not be useful for Cu, Zn, Mn, and Pb.  相似文献   

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