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1.
Electrolyzed reduced water (ERW) has attracted much attention because of its therapeutic effects. In the present study, a new culture medium, which we designated Water medium, was developed to elucidate the effects of ERW on the lifespan of Caenorhabditis elegans. Wild-type C. elegans had a significantly shorter lifespan in Water medium than in conventional S medium. However, worms cultured in ERW-Water medium exhibited a significantly extended lifespan (from 11% to 41%) compared with worms cultured in ultrapure water-Water medium. There was no difference between the lifespans of worms cultured in ERW-S medium and ultrapure water-S medium. Nematodes cultured in ultrapure water-Water medium showed significantly higher levels of reactive oxygen species than those cultured in ultrapure water-S medium. Moreover, ERW-Water medium significantly reduced the ROS accumulation induced in the worms by paraquat, suggesting that ERW-Water medium extends the longevity of nematodes at least partly by scavenging ROS.  相似文献   

2.
The fatty acid composition of membranes of L-forms ofStreptococcus faecalis andProteus mirabilis cultured at different osmolalities and in different osmotic stabilizers was examined.S. faecalis L-forms cultured with sucrose in the medium showed a decrease in the unsaturated fatty acid C181 and an increase in the C18 fatty acid and C19 cyclopropane fatty acid. Fatty acid composition ofS. faecalis L-forms cultured in medium containing 1.8% NaCl was similar to the fatty acid composition of L-forms cultured in brain-heart infusion broth (BHI) without osmotic stabilizer and was between the composition of fatty acids of L-forms in BHI with sucrose and that in BHI without 0.5 M sucrose. InProteus mirabilis L-forms, there were differences between L-forms cultured with and without sucrose, but these differences were not comparable to the changes observed inS. faecalis L-forms.P. mirabilis L-forms cultured with and without NaCl in the medium had similar fatty acid compositions.  相似文献   

3.
The purpose of this research was Eucalyptus saligna in vitro regeneration and transformation with P5CSF129A gene, which encodes Δ1-pyrroline-5-carboxylate synthetase (P5CS), the key enzyme in proline biosynthesis. After selection of the most responsive genotype, shoot organogenesis was induced on leaf explants cultured on a callus induction medium (CI) followed by subculture on a shoot induction medium (SI). Shoots were subsequently cultured on an elongation medium (BE), then transferred to a rooting medium and finally transplanted to pots and acclimatized in a greenhouse. For genetic transformation, a binary vector carrying P5CSF129A and uidA genes, both under control of the 35SCaMV promoter, was used. Leaves were co-cultured with Agrobacterium tumefaciens in the dark on CI medium for 5 d. The explants were transferred to the selective callogenesis inducing medium (SCI) containing kanamycin and cefotaxime. Calli developed shoots that were cultured on an elongation medium for 14 d and finally multiplied. The presence of the transgene in the plant genome was demonstrated by PCR and confirmed by Southern blot analysis. Proline content in the leaves was four times higher in transformed than in untransformed plants while the proline content in the roots was similar in both types of plants.  相似文献   

4.
An efficient micropropagation protocol was established for Cryptocoryne wendtii and Cryptocoryne becketti using shoot tips explants. Multiple shoots were induced from shoot tip explants of both species cultured on agar-gelled as well as liquid MS medium supplemented with 0.5 mg/L BA and 0.2 mg/L IBA (proliferation medium). The multiple shoots of both the species formed on agar-gelled as well as liquid medium were vigorously growing with well-developed roots and leaves after 4 weeks of culture. Highest number of multiple shoots was obtained from shoot tip explants of both the species cultured in liquid proliferation medium after 4 weeks of culture. The shoot tip explants of C. wendtii and C. becketti, that were cultured in liquid proliferation medium (2 weeks) followed by culturing on agar-gelled proliferation medium (2 weeks) also produced the multiple shoots. Shoot tips cultured on agar-gelled medium produced the least number of multiple shoots after 4 weeks of culture. Histological study did not show any abnormalities in the leaves of in vitro plantlets of both the species, cultured in agar-gelled and liquid proliferation medium. The leaves of the in vitro plantlets formed normal mesophyll cells and vascular bundles. More than 95% of the acclimatized plantlets grew vigorously without any morphological abnormalities.  相似文献   

5.
Expression of capsule-associated genes of Cryptococcus neoformans   总被引:2,自引:0,他引:2  
Cryptococcus neoformans produces an extracellular polysaccharide capsule that is related to its virulence. The production of capsular components was reported to be accelerated when cultured on media with lower amount of glucose. In this study, relationship between capsule synthesis and expression of capsule-associated genes (CAP genes) was investigated by quantitative real-time PCR analysis. Normally encapsulated strains and a stable acapsular strain were cultured in 1% polypepton medium with 0.1% or 15% glucose. The results of assessment of the capsule size showed that the capsule of yeast cells cultured in the medium with low amount of glucose was thicker than that with high amount of glucose. The CAP gene expressions of normally encapsulated strains were higher in the medium with 0.1% glucose than in the medium with 15% glucose. Furthermore, CAP10, CAP59 and CAP60 genes were expressed very low in a stable acapsular strain, and CAP64 gene was not expressed. Results of assessment of capsule size and CAP gene expressions by quantitative real-time PCR analysis indicated that CAP gene expressions might be related to the production of capsule, and that glucose concentration in culture media might be related to the expression of CAP genes.  相似文献   

6.
We compared serum and protein-free cultures ofa ras-amplified recombinant BHK-21 cell line(ras-rBHK-IgG), which hyperproduces a lungcancer specific recombinant human monoclonal antibody. Ras-rBHK-IgG cells were shown to grow well, evenin protein-free medium and to be morphologicallysimilar to cells cultured in serum containing medium. However, the growth rate of ras-rBHK-IgG cellswas considerably slower in protein-free medium, whichresults in a longer maintenance period compared with cells cultured in serum containing medium. In addition, it was found that antibody production in protein-free culture had a ten times higher maximum than cells cultured in serum containing medium. On theother hand, in high density culture, using the hollowfiber bioreactor system, ras-rBHK-IgG cellscould be maintained for a month in protein-freeculture in contrast with serum culture, which onlylasted for half a month. However, the markedincrease of antibody production was not observed. A total amount of about 15 mg of the recombinantantibody, obtained in protein-free culture, was abouttwo times of that obtained in serum culture, and wasshown to be reactive to lung cancer cells in tissue. From these properties in protein-free medium, it isconcluded that protein-free culture of ras-rBHK-IgG cells is suitable for middle scaleproduction of recombinant human monoclonal antibody.  相似文献   

7.
Hairy roots were obtained following inoculation of the stems of Lobelia inflata L. with Agrobacterium rhizogenes strain ATCC 15834. These hairy roots contained agropine and mannopine. In addition, lobeline was detected by HPLC and confirmed by mass spectrometry. Various media were tested for the growth of hairy roots as well as for the content of lobeline in hairy roots. The growth rate of hairy roots cultured in Nitsch and Nitsch's medium was approximately one third of those cultured in other media. The lobeline content of hairy roots (18–54 g/g dry weight) cultured in these media was the same order of magnitude compared with that of roots of L. inflata (24 g/g dry weight) cultivated in pots. The hairy roots cultured in Nitsch and Nitsch's medium were morphologically different from those cultured in other media.Abbreviations MS medium Murashige and Skoog's medium - 1/2 MS medium one-half strength of the standard Murashige and Skoog's medium - B5 medium Gamborg's B5 medium - NN medium Nitsch and Nitsch's medium - FW fresh weight - DW dry weight  相似文献   

8.
Growth of coffee (Coffea arabusta) plantlets cultured in vitroas affected by sugar, types of supporting material and number of air exchanges of the vessel was investigated. Single node cuttings of in vitro coffee plantlets were cultured on half strength MS medium with or without 20 g l−1 sucrose. Two types of supporting material, agar and Florialite, and two levels of air exchange expressed by number of air exchanges per vessel, 0.2 and 2.3 h−1, were studied. At the end of a 40-day culture period, fresh weight, shoot length, root length and leaf area of plantlets when cultured on Florialite soaked in sugar-free medium and under the higher number of air exchanges were greater than those in sugar containing medium. Callus was observed at the shoot base of plantlets grown on agar medium containing sucrose. Photosynthetic ability of coffee plantlets in vitro was also significantly increased when grown on sugar-free medium with the high number of air exchanges and Florialite as a supporting material. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

9.
Summary Bicarbonate in the culture medium is essential for DNA synthesis of primary cultured rat hepatocytes stimulated by epidermal growth factor (EGF). When primary cultured hepatocytes in supplemented Leibovitz L15 medium were placed in a 100% air incubator, no increase in DNA synthesis was observed even after stimulation by EGF. However, when these cells were cultured with NaHCO3 and EGF and placed in a 5% CO2:95% air incubator, a stimulus of DNA synthesis more than 10-fold greater than in cultures in air only was seen, and many mitotic figures could be identified. Furthermore, NaHCO3 added to supplemented DMEM/F12 medium enhanced the DNA synthesis of primary cultured rat hepatocytes in this medium. The ideal pH of the medium for DNA synthesis of cultured hepatocytes was in the range of 7.6 to 8.0. A dose response of NaHCO3 in several media showed that DNA synthesis of the cells increased as the concentration of NaHCO3 increased and that 25 to 30 mM NaHCO3 in the medium was optimal for the replication of DNA by primary cultured rat hepatocytes. The investigations described in this study were supported in part by grants CA-07175, CA-22484, and CA-45700 from the National Cancer Institute, Bethesda, MD.  相似文献   

10.
赵能  原晓龙  华梅  李苏雨  王娟  王毅 《广西植物》2017,37(2):242-247
地衣是一种传统的民族药物,能产生多种具有活性的物质。该研究对地衣型真菌(Xanthoria elegans,Myelochroa indica,Ramalina peruviana,Cladonia macilenta,Nephromopsis pallescens,Cladonia coccifera)进行液体培养,2个月后,培养液用乙酸乙酯萃取后获得初提物。该研究采用抑菌圈法评价地衣型真菌初提物对7种致病细菌(Bacillus subtilis,Bacillus cereus,Vibrio parahaemolyticus,Straphylococcus haemolyticus,Pseudomonas aeruginosa,Staphylococcus aureus,Micrococcus luteus)的抗菌活性,并测定最低抑菌浓度(MIC)。结果表明:6种地衣型真菌的初提物均具有一定的抗菌活性,且不同培养基对地衣型真菌产生抗菌物质有显著影响。其中,R.peruviana在MY液体培养基中所产生的次级代谢产物对金黄色葡萄球菌、藤黄微球菌、溶血性葡萄球菌、铜尿假单胞菌具有抑制效果,但在YMG培养基中所得初提物对供试7种致病细菌不具有抑菌效果。X.elegans在YMG培养基中所得初提物对枯草芽孢杆菌具有明显抗菌活性,其抑菌圈直径可达17.77 mm。该研究证实不同地衣型真菌液体培养初提物具有抗菌活性,不同的培养基也直接影响地衣型真菌抗菌效果。该研究结果为地衣型真菌的进一步研究及民族药的开发利用奠定了基础。  相似文献   

11.
Sweet potato (Ipomoea batatas (L.) Lam.) breeding has been hampered by self-and cross-incompatibilities that are frequently encountered among the plants in the section Batatas. Ovule culture techniques were developed to assist in overcoming some of these incompatibilities. Ovules that contain embryos at the late globular to heart shaped stage of development were cultured on MS medium containing full strength or one-half strength salts with 3%, 8% or 12% sucrose. Ovules were cultured either intact or after slicing. Ovules of I. triloba and I. trifida were successfully cultured as early as 3 and 4 days after pollination while sweet potato ovules were successfully cultured 5 and 6 days after pollination. The percentage of ovules with developing embryos on the media tested ranged from 27.8% to 50.2%. The highest percentage of embryos developed when the ovules were sliced and cultured on medium containing one-half MS salts and 8% sucrose. Three plants were recovered from cultured ovules of incompatible interspecific crosses.Abbreviations DAP days after pollination - MS medium Murashige and Skoog (1962) medium  相似文献   

12.
Rat pheochromocytoma PC12 cells die when cultured in serum-free medium. Neurotrophic factors can rescue PC12 cells from cell death, and induce neuronal differentiation. To further investigation the relationship among cell death, survival, and differentiation, the bcl-2 cDNA, which is known to prevent apoptosis in various types of cells, was transfected into PC12 cells. Six monoclonal bcl-2-transfected cell lines were isolated and confirmed to express mRNA and protein product of bcl-2. The wild-type and bcl-2-transfected PC12 cells were kept to adhere to collagen-coated dishes at the inintiation of serum-free experiments to avoid cellular damage due to detachment of the cells by triturtion. Even under the conditions, the control PC12 cells mostly died within 24 h, when cultured in serum-free medium whereas those expressing Bcl-2 survived even for 7 days in serum-free medium. Moreover, outgrowth of long processes in thebcl-2-transfected cells was only observed under the condition to keep the cells attached to the dishes in serum-free medium without any additive neurotrophic or growth factors. Neurofilament medium protein, which is a neuron-specific cytoskeletal component, was also expressed in the differentited cells, suggesting that the long processes in bcl-2-transfected PC12 cells are neurites. However, neuronal differentiation of PC12 cells expressing Bcl-2 was not observed when cultured in serum-containing medium. Accordingly, survival of PC12 cells expressing Bcl-2 under the condition which cells usually die may be accompanied with neuronal differentiation. 1994 John Wiley & Sons, Inc.  相似文献   

13.
Summary Hairy root cultures of Lithospermum erythrorhizon were established by transformation of in vitro grown shoots with Agrobacterium rhizogenes 15834. Hairy roots cultured on Murashige and Skoog solid medium did not produce any red pigments. However, the hairy roots cultured in Root Culture solid or liquid media produced a large amount of red pigments, which were released to the medium. The addition of adsorbents to the culture medium stimulated shikonin production by ca. 3-fold. Using this method an air-lift fermenter system was established, equipped with a XAD-2 column, which continuously produced ca. 5 mg/day of shikonin during a period of more than 220 days.  相似文献   

14.
Summary Shoot apex, nodal, and leaf explants of Stevia rebaudiana Bertoni can regenerate shoots when cultured on Murashige and Skoog (MS) medium supplemented with 6-benzyladenine (BA; 8.87 μM) and indole-3-acetic acid (5.71 μM). Rooting of the in vitro-derived shoots could be achieved following subculture onto auxin-containing medium. A survival rate of 70% was recorded at the hardening phase on the substrate cocopeat. The presence of the sweet diterpene glycosides, viz. stevioside and rebaudioside, was confirmed in the in vitro-derived tissues of Stevia using HPTLC techniques. Callus cultured on agar-solidified MS medium supplemented with BA (8.87 μM) and indole-3-butyric acid (9.80 μM) showed the highest sweetener content.  相似文献   

15.
Embryo dormancy of Taxus baccata var. fastigiata is eliminated when cultured continuously in nutritive liquid medium. An equivalent percentage of germination is obtained when the embryos are transferred to agar medium after 8 days of liquid culture. There is no morphological development of the embryo during the period in the liquid medium. But we have ascertained that water-soluble germination inhibitors present in the embryo are leached out into the medium, permitting germination. Germination is totally absent when the embryos are cultured continuously in distilled water, alone or with minerals; incidental in sucrose solution; and maximal when the medium contains sucrose and Ca2+ or K+ ions. The extent of germination on agar medium depends upon the composition of the liquid medium in which the embryos are cultured for the initial 8 days. But this preliminary culture in the liquid medium does not always remove the endogenous inhibitors, irrespective of its composition. This can be achieved only in the presence of sucrose; and this process can be made more effective by the addition of Ca2+ ions.  相似文献   

16.
Summary A procedure for culturing detached panicles of sorghum, Sorghum bicolor (L.) Moench, was developed to achieve flowering, fertilization, and subsequent seed development and maturation in vitro. Sixteen sorghum genotypes (five high and eleven low in tannin) were tested for their ability to develop normally in culture. Panicles collected one to two days before the initiation of anthesis were cultured in flasks containing liquid medium. Contamination and medium darkening were the major obstacles encountered. Up to 55% of the panicles cultured reached physiological maturity in vitro. The frequency of seed set ranged from 30 to 97% depending upon genotype and medium. Seed and glume color were normal. Seed produced in vitro resembled those grown in vivo and germinated well, but were smaller than normal (100 kernel weight reached 50 to 70% of the control). Grain polyphenols were synthesized in the cultured panicles. Seed of high tannin genotypes produced in vitro were lower in total phenols and tannins and higher in flavan-4-ols and the 3-deoxyanthocyanidin pigments than control seed. This technique can be used for harvesting late-maturing stocks and for various sorghum studies.  相似文献   

17.
The red alga Digenea simplex was cultured with various culture media to clarify the nutritional conditions to produce kainic acid (KA ). Unlike the domoic acid‐producing red alga Chondria armata , D. simplex was insensitive to excessive manganese, and grew best (mean growth rate approximately 800% for 25 days) in modified PES medium (mPES ; seawater + nitrate, phosphate, iron, trace metals, vitamins, and 2‐[4‐(2‐hydroxyethyl)‐1‐piperazinyl]‐ ethanesulfonic acid) prepared with autoclaved seawater. Liquid chromatography‐mass spectrometry analysis of the algal extracts revealed that the KA content of the explants cultured with mPES or N·P·Fe medium (seawater + nitrate, phosphate, and iron) was somewhat higher than that of wild specimens (1748–2378 μg g?1 vs 1562 μg g?1). The 1H‐nuclear magnetic resonance spectrum of the KA extracted and purified from pooled explants was indistinguishable from the previously reported KA spectrum. When D. simplex was cultured for 6 weeks with medium in which NaNO 3 of mPES was replaced by Na15NO 3, the ratio of 214KA to total measured KA (totalKA = 213KA + 214KA ) in the cultured explants (0.1 at the beginning of culture) gradually increased to 2.5, indicating that D. simplex produces KA in proportion to its growth under the condition in which sufficient nitrogen source is available.  相似文献   

18.
Summary Hairy root culture of Hyoscyamus albus was established by transformation with Agrobacterium rhizogenes strain A4. The growth and production of five tropane alkaloids were investigated under various culture conditions. Among the four basal culture media tested, Woody Plant medium was the best for growth of the hairy roots, but a high amount of tropane alkaloids was obtained with Gamborg's B5 medium. Sucrose concentration in B5 medium had little effect on the growth, while 3% sucrose was suitable for the alkaloid production. Addition of KNO3 to Woody Plant medium affected the growth, whereas the alkaloid content was not markedly improved. Supplement of some metal ions to B5 medium stimulated the alkaloid production. In particular, Cu2+ remarkably enhanced both the growth and the alkaloid yield. The hairy roots cultured under 16 h/day light survived for more than 32 days compared with those cultured in the dark.Abbreviations EDTA ethylenediaminetetraacetic acid - HPLC high performance liquid chromatography - MeOH methanol - MS medium Murashige and Skoog medium - WP medium McCown's Woody Plant medium - B5 medium Gamborg B5 medium - wt weight  相似文献   

19.
Summary Cultured pig aortic smooth muscle cells maintain a viable, quiescent state in a chemically defined medium that contains 10−6 M insulin, 5μg/ml transferrin, and 0.2 mM ascorbate. DNA synthesis and DNA content were determined by measuring tritiated thymidine incorporation and DNA-binding to the fluorescent probe 4′,6-diamidino-2-phenylindole, respectively. The majority of the population of cells in defined medium cultures were diploid. Tritiated thymidine uptake in cells in defined medium was one-tenth that observed in cells in fetal bovine serum-containing medium. The study of cellular cyclic AMP level in response to extracellular adenosine stimulation in dividing cells and quiescent cells showed that cells in defined medium had a lower extent of response to adenosine compared to cells cultured in serum-containing medium. Both the cell growth index and the response to adenosine of cells cultured in defined medium were reversible after replacing the medium with 10% fetal bovine serum-containing medium, which suggests that the cells in defined medium were healthy and were capable of modulating cellular metabolism depending on culture conditions. This work was supported in part by National Institutes of Health grants HL31854, HL38130, and RR07048.  相似文献   

20.
The influence of varied concentrations of sucrose and ammonical (NH4+) nitrogen on in vitro induction and expression of anthocyanin pigments from Rosa hybrida cv. ‘Pusa Ajay’ was investigated. Of two explants (petal and leaf discs) selected and cultured under two different conditions (light and dark), leaf discs were found to be most suitable for callus initiation. Profuse and early callus induction was observed when leaf discs of rose were cultured under total dark conditions on solid Murashige and Skoog (MS) medium supplemented with 4.0 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D). Early pigment initiation, enhancement and maximum anthocyanin production from calluses were recorded when leaf discs were cultured on Euphorbia millii (EM) medium supplemented with 7% sucrose compared with calluses cultured at 4% sucrose concentration under 16/8 h (light/dark) photoperiod regime. Reducing the concentration of NH4+ nitrogen in the solid MS medium led to slight improvement in anthocyanin production in rose leaf calluses.  相似文献   

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