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1.
Oxytocin, a peptide animal hormone, was used as a growth regulator to test its effect on biomass accumulation and production of secondary plant constituent glycyrrhizin in the cell cultures of Abrus precatorius. Glycyrrhizin is an important phytoconstituent of liquorice which is widely used in the pharmaceutical and food industries. Cell suspension cultures of A. precatorius were developed from leaf explant of in vitro germinated plant in Murashige and Skoog medium supplemented with 30 g/l sucrose, 1 mg/l naphthalene acetic acid and 1 mg/l kinetin. The influence of oxytocin on biomass accumulation as well as on the production of glycyrrhizin was observed in the cell cultures of A. precatorius. Treatment of A. precatorius cell cultures with 100 μg/l oxytocin, improved glycyrrhizin production up to 34.27 mg/l on the dry cell weight basis third day after oxytocin treatment, which is over four times that of the control cultures, simultaneously nearly two fold increase in the biomass 2 days after the oxytocin treatment was recorded over the control cultures.  相似文献   

2.
Synchronization of estrous and fixed-time artificial insemination (FTAI) was conducted during the reproductive season of 2008 (March–April) in a local red deer breeding farm in Argentina. Multiparous suckling hinds (n = 38) were artificially inseminated following hormonal treatment (intravaginal sponge containing 100 mg of medroxiprogesterone acetate). At the time of sponge removal (day 12) 250 IU of eCG and 500 μg of PGF2α were given to each hind. The FTAI was performed at 48–55 h after device removal with cryopreserved semen imported from New Zealand. Rectal-transcervical AI method (similar to that in cattle) was performed and semen was deposited within the uterine body (n = 28) or the cervix (n = 10). Pregnancy was diagnosed by means of ultrasonography 44 days after FTAI. The overall pregnancy rate was 36.8% (14/38). Percentage of does that became pregnant with intrauterine seminal deposition was 42.9% (12/28) whereas pregnancy rate in the hinds with intracervical AI was 20% (2/10; P = 0.27).  相似文献   

3.
4.
The effect of abiotic and biotic elicitors (methyl jasmonate, chitosan, salicylic acid, Agrobacterium, and yeast extract) at various concentrations on total isoflavonoid accumulation was studied in the hairy root cultures of Pueraria candollei. All elicitors stimulated isoflavonoid production. Yeast extract (0.5 mg/ml) was the most efficient giving total isoflavonoids at 60 ± 1 mg/g dry wt, which was 4.5-fold higher than control hairy roots on day 3 of elicitation.  相似文献   

5.

Dibenzocyclooctadiene lignans are a specific group of secondary metabolites that occur solely in Schisandra chinensis. The aim of the presented work was to boost the accumulation of lignans in the agitated microshoot cultures of S. chinensis, using different elicitation schemes. The experiments included testing of various concentrations and supplementation times of cadmium chloride (CdCl2), chitosan (Ch), yeast extract (YeE), methyl jasmonate (MeJa), and permeabilizing agent—dimethylsulfoxide (DMSO). After 30 days, the microshoots were harvested and evaluated for growth parameters and lignan content by LC-DAD method. The analyses showed enhanced production of lignans in the elicited S. chinensis microshoots, whereas the respective media samples contained only trace amounts of the examined compounds (< 5 mg/l). Elicitation with CdCl2 caused up to 2-fold increase in the total lignan content (max. ca. 730 mg/100 g DW after the addition of 1000 μM CdCl2 on the tenth day). Experiments with chitosan resulted in up to 1.35-fold increase in lignan concentration (max. ca. 500 mg/100 g DW) after the supplementation with 50 mg/l on the first day and 200 mg/l on the tenth day. High improvement of lignan production was also recorded after YeE elicitation. After the elicitation with 5000 mg/l of YeE on the first day of the growth period, and with 1000 and 3000 mg/l on the 20th day, the lignan production increased to the same degree—about 1.8-fold. The supplementation with 1000 mg/l YeE on the 20th day of the growth cycle was chosen as the optimal elicitation scheme, for the microshoot cultures maintained in Plantform temporary immersion system—the total content of the estimated lignans was equal to 831.6 mg/100 g DW.

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6.

Plant cell suspension cultures of Thevetia peruviana has been explored for pharmaceutical compounds production. The aim of this study was to evaluate the agitation rate effect on growth and metabolism behavior of T. peruviana cells grown in a 7 L stirred tank reactor. Increases in agitation rates favored cell growth, secondary metabolites production and metabolic activity. The highest biomass concentration 11.92?±?0.25 g DW/L was reached at 550 rpm. The oxidase-reductase activity was stimulated at 550 and 800 rpm. Guaiacol peroxidase activity showed an increase for 300 and 550 rpm after day 7. High levels of extracellular Reactive Oxygen Species (ROS) were observed at day 7 for 550 and 800 rpm. Intracellular phenolic compounds (PC) showed an upward trend until day 7 with a maximum phenolic production of 57.78?±?4.70 mg EGA/100 g FW for 550 rpm. These results indicated that cells responded to ROS stress in a non-enzymatic manner during the first 7 days of culture, increasing PC production with antioxidant capacity. After 7 days, cells responded enzymatically. Intracellullar cardiac glycoside showed a relative increase of 1.7 and 2.1 times for 550 and 800 rpm, respectively. The maximum extracellular production of cardiac glycoside for 550 and 800 rpm was 770.34?±?42.84 mg EP/L. Taken together this study established reactor culture conditions for production of cardiac glycosides and PC, especially taxifolin.

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7.
The present study was designed to incubate luteal cells isolated from pseudopregnant cats and to investigate the effects of cholesterol and cAMP on luteal progesterone production. Corpora lutea were collected from the cats on days 10 and 15 of pseudopregnancy. Luteal cells were isolated from the ovaries by collagenase digestion. Steroidogenic luteal cells were stained for 3β-hydroxysteroid dehydrogenase (3β-HSD) activity. Cells (2 × 104) staining positive for 3β-HSD were cultured for up to 7 days. The cells were treated with 22(R)-hydroxycholesterol (22R-HC) and dibutyryl cyclic AMP (dbcAMP) on days 1, 3 and 7.Treatment of cells with 22R-HC resulted in a dose-dependent increase (p < 0.001) in progesterone production. When 22R-HC was used at a concentration of 10 μg/ml, it resulted in 2.7- and 5.1-fold increases in progesterone production on days 3 and 5, respectively. When the dose was doubled (20 μg/ml), treated cells produced four times more progesterone on days 3 and 7, and three times more on day 5. By day 7, progesterone production increased up to 9.1 times more than the control.Incubation of cells with both concentrations of dbcAMP (0.1 mM and 1 mM) resulted in significant stimulations of progesterone on days 5 and 7 (p < 0.001). However, on day 3, only higher doses of dbcAMP (1 mM) resulted in significant stimulation (p < 0.05). Progesterone production was increased up to 2- and 2.9-fold of the control when cells were treated with lower concentration of dbcAMP (0.1 mM) on days 5 and 7, respectively. Incubation of cells with 1 mM concentrations of dbcAMP induced a 3.2-fold increase on day 5 and a 5-fold increase on day 7.In conclusion, a successful incubation was performed for long-life culturing of luteal cells collected from pseudopregnant cats. The method works well and allows for optimal growth and development of cells in the culture. The present study also demonstrated that incubating cat luteal cells with 22R-HC and dbcAMP induces a significant increase in luteal progesterone synthesis.  相似文献   

8.
Hexanal produced by cells of a recombinant Yarrowia lipolytica yeast expressing the hydroperoxide lyase (HPL) from green bell pepper fruit was studied under oxido-reducing conditions using the reducing dithiotreitol and oxidizing potassium ferricyanide compounds. The combined effect of pH, linoleic acid 13-hydroperoxides concentration, temperature and oxido-reducing molecules on the hexanal production was studied. Significant positive effects for the hexanal production were found using high concentrations of hydroperoxides (100 mM, 30 g/L). Adding reducing molecules enhanced significantly hexanal production while the oxidizing molecules had an inhibitory effect. Combined effects of 13-hydroperoxides and dithiotreitol were optimised by a central composite design and a model was proposed. Finally, 6 mM (600 mg/L) of hexanal was obtained when 119 mM of 13-hydroperoxides (37 g/L) and 50 mM of dithiotreitol were introduced directly in the biocatalytic medium of the yeast Y. lipolytica.  相似文献   

9.
The morphological type of a microorganism generally influences its metabolite production. In the present study, we investigated the effects of the mycelial morphology of shiitake (Lentinula edodes) on the production of 2-mercaptohistidine trimethylbetaine (ergothioneine, ESH) during liquid fermentation. Analyses of the distribution of ESH in mycelial cells of different morphological types revealed that the ESH content of pellets obtained from the liquid fermentation media was much greater than the content in the free mycelia and clumps. The concentration of ESH in pellets on day 15 of liquid fermentation reached 0.79 mg/g dry weight (DW), which is approximately three times the concentration found in mycelia clumps (0.28 mg/g DW) and free mycelia (0.31 mg/g DW). Macroscopic image analysis of the development and morphological changes of the pellets during a liquid fermentation period of up to 25 days indicated that pellet growth showed a highly positive correlation with the increase in ESH concentration (r 2 = 0.9851). A reduced agitation rate of 50 rpm for the culture medium was suitable for pellet formation and size enlargement. The results obtained in this work would be helpful in guiding the intentional manipulation of the distribution and enrichment of ESH in L. edodes through changes in liquid fermentation conditions.  相似文献   

10.
Treatment of Linum album cell cultures with 10 μM salicylic acid (SA) for 3 days improved podophyllotoxin (PTOX) production up to 333 μg/g dry weight (DW): over three times that of the control cultures. qPCR analyses showed that in SA-treated cells, the expression of the genes coding for phenylalanine ammonia-lyase (PAL), cinnamoyl-CoA reductase (CCR) and cinnamyl-alcohol dehydrogenase (CAD), all involved in the first steps of PTOX biosynthesis, also increased reaching a peak 8–12 h after the treatment. Expression of the pinoresinol-lariciresinol reductase gene (PLR), which is involved in one of the last biosynthetic steps, was not affected by SA. The selective action of SA on these genes can be applied to control the biotechnological production of this anticancer agent.  相似文献   

11.
Plant cell cultures of Centella asiatica produce small quantities of centellosides: madecassosid > asiaticosid > madecassic acid > asiatic acid. To obtain a more efficient production system of these bioactive triterpenoid compounds, we developed a process where the substrate, α-amyrin, was converted into centellosides by cell suspensions of C. asiatica. When α-amyrin in acetone was added at 0.01 mg/ml−1 to the culture medium, together with the permeabilizing agent DMSO, after 7 days nearly 50% had penetrated the plant cells, of which almost 84% was transformed into centellosides. The system therefore efficiently converts α-amyrin into centellosides, thus opening a new possibility for the production of these compounds.  相似文献   

12.
13.
A fed-batch culture process followed by subsequent photoautotrophic induction was established for the high density culture of astaxanthin-rich Haematococcus pluvialis using a CO2-fed flat type photobioreactor under unsynchronized illumination. Fed-batch culture was performed with an exponential feeding strategy of the growth-limiting nutrients, nitrate and phosphate, concurrently with the stepwise supplementation of light depending on the cell concentration. During the growth phase, a biomass of 1.47 g/L was obtained at a biomass productivity of 0.33 g/L/day. Photoautotrophic induction of the well-grown vegetative cells was performed consecutively by increasing the light intensity to 400 μmol photon/m2/s, while keeping the other conditions in the CO2-fed flat type photobioreactor fixed, yielding an astaxanthin production of 190 mg/L at an astaxanthin productivity of 14 mg/L/day. The proposed sequential photoautotrophic process has high potential as simple and productive process for the production of valuable Haematococcus astaxanthin.  相似文献   

14.
The effect of ozone on the respiration of three species of adult stored-product Coleoptera was tested in an air-tight flask. Sitophilus oryzae (L.), Rhyzopertha dominica (F.) and Tribolium castaneum (Herbst) adults were exposed to atmosphere containing 0.1, 0.2 or 0.4 μg/ml initial ozone at 23–25 °C and 50% r.h. Carbon dioxide (CO2) production reflected the respiration rates of insects and was determined with a gas chromatograph (GC). The experiments showed that the effects of ozone on respiration had two distinct phases. Phase 1 involved a lower respiration rate of the adult stored-product Coleoptera under ozone atmosphere and reflected the need for insects to reduce ozone toxicity. After 1 h, CO2 production of S. oryzae was 3.19, 2.63, 2.27 and 1.99 μl/mg for the ozone concentration of 0, 0.1, 0.2 and 0.4 μg/ml, respectively. The results also showed that there were decreases in the rate of respiration in R. dominica and T. castaneum with an increase in ozone concentration. During phase 2, respiration of S. oryzae, R. dominica, and T. castaneum adults treated with ozone increased as the ozone degraded to oxygen. After 7 h, the effect of ozone on CO2 production, relative to the control, changed from a decrease to an increase. The findings in relation to control strategies were discussed.  相似文献   

15.
Cell immobilization has been proposed as a useful technique for mass production and efficient purification of secondary metabolites. In this study, we compared the bio-productivity of ligand-free and Ca-alginate-immobilized mulberry cells for rutin and γ-amino butyric acid (GABA). In the leaves of Subong mulberry plants (M. bombycis K.) grown in a greenhouse, GABA accumulated as the leaves aged; a more than a 20-fold increase of GABA was observed in leaves undergoing senescence than in younger leaves. In contrast, more rutin was detected in mature leaves than in young leaves and those undergoing senescence. The production of total proteins in ligand-free leaf callus cells dramatically increased until 6 days after incubation in liquid suspension media (from 6.5 mg/g callus at day 0–14.5 mg/g callus), and by day 15 dropped to levels similar to those seen in the 0-day control. In contrast, immobilized cells showed a slight increase and then an insignificant decrease in protein content during the 15-day incubation period. Interestingly, immobilized mulberry cells more efficiently produced and secreted rutin and GABA into the suspension media than ligand-free cells. KN, a cytokinin, enhanced this production while 2,4-dichlorophenoxyacetic acid(2,4-D), an auxin, alleviated the effect of KN. As a result, incubation of the immobilized Subong cells in a full-strength Murashige and Skoog (MS) liquid medium containing 1 mg/l of 2,4-D and 0.1 mg/l KN, among the hormone combinations in the medium we tested, produced the highest amounts of rutin (8.2 μg/g callus cells) and GABA (305 μg/g callus cells) and secreted the largest amounts into the suspension media.  相似文献   

16.
Extracellular pigment production by immobilised Monascus purpureus C322 has been studied in repeated-batch processes using different immobilising carriers such as Ca-alginate, polyurethane sponge, active carbon and pearlite. With Ca-alginate, pigment production was maximum (30.5 UA470 as process mean production, three batches) while the cell leakage was negligible (0.4 g l−1 free biomass) and the bead mechanical stability good; with this carrier, an extended repeated-batch fermentation (nine batches, 55 days) was carried out: the process pigment productivity was 3.87 UA470 day−1.  相似文献   

17.
The co-culture of the suspension cells of Taxus chinensis var. mairei and its endophytic fungi, Fusarium mairei, in a 20-L co-bioreactor was successfully established for paclitaxel production. The co-bioreactor consists of two-unit tanks (10 L each) with a repairable separate membrane in the center, culturing Taxus suspension cells in one tank and growing fungi in another. By optimizing the co-culture conditions, there was a desirable yield of paclitaxel in Taxus cell cultures. The Taxus cell cultures by co-culture produced 25.63 mg/L of paclitaxel within 15 days; it was equivalent to a productivity of 1.71 mg/L per day and 38-fold higher than that by uncoupled culture (0.68 mg/L within 15 days). The optimum conditions for co-culture in the co-bioreactor were: B5 medium, inoculating fungi when Taxus cells had grown for 5 days in the co-bioreactor, hydrophilic separate membrane in the center of the co-bioreactor, and air flow rate of 1:0.85 v/v/m in fungus cultures.  相似文献   

18.
Summary Permeabilized Coleus blumei cells were cultivated in an immobilized state to study the effect of dimethyl sulfoxide (DMSO) concentrations and growth regulators on cell growth and rosmarinic acid (RA) production characteristics. Luffa (the fibrous skeleton of mature fruit of Luffa cylindrica) was a good support matrix for cell immobilization because of its high void volume. Maximum cell loading capacity was 1.33 g dry cell weight (DCW)/g dry Luffa. The experiments were done in shake flasks with no free medium. The medium was supplied in a fed-batch mode to avoid the flotation of Luffa pieces. The sucrose in the medium was completely hydrolyzed to glucose and fructose without any sugar accumulation in the medium. The cell viability was slightly higher in the cells on top of the Luffa than those in the middle. Cell growth rate and rosmarinic acid (RA) production were approximately half that obtained in cell suspension cultures. Cell yield (g DCW/g glucose) was similar to that of cell suspension cultures. The absence of growth regulators did not promote an increase of RA production but did decrease the cell mass. The second step preconditioning with 0.5% DMSO did not improve the cell's adaptability to higher DMSO concentrations and the cell mass did not increase with 2.5% DMSO.  相似文献   

19.
The novel exopolysaccharide bioflocculant HBF-3 is produced by Halomonas sp. V3a′, which is a mutant strain of the deep-sea bacterium Halomonas sp. V3a. Response surface methodology (RSM) was employed to optimize the production medium for increasing HBF-3 production. Using a Plackett–Burman experimental design to aid in the first step of optimization, edible glucose, MgSO4·7H2O, and NH4Cl were found to be significant factors affecting HBF-3 production. To determine the optimal concentration of each significant variable, a central composite design was employed. Based on response surface and canonical analysis, the optimum concentrations of the critical components were obtained as follows: edible glucose, 16.14 g/l; MgSO4·7H2O, 2.73 g/l; and NH4Cl, 1.97 g/l. HBF-3 production obtained by using the optimized medium was 4.52 g/l, which was in close agreement with the predicted value of 4.55 g/l. By scaling up fermentation from flask to fermenter, HBF-3 production was further increased to 5.58 g/l.  相似文献   

20.
Aim of the present study was to evaluate in vitro toxicity and in vivo antibacterial, anti-inflammatory, antiulcer, and antioxidant activities of two organoselenium compounds, selenocystine (SeCys) and ebselen (Ebs). The study was conducted in experimentally induced ulcers in rodent model infected with Helicobacter pylori (H. pylori). In vitro toxicological studies on normal spleenic lymphocytes revealed that SeCys and Ebs were non-toxic to the cells even at 100 μM concentration. Antibacterial activity was observed at 500 μg/mL concentration of either of the compounds against H. pylori. In vivo studies after treatment with SeCys and Ebs (500 μg/kg/day) resulted in significant reduction in ROS production and inhibition of lipid peroxidation in gastric tissue. The antioxidant and anti-inflammatory activities of both the compounds were also confirmed by their ability to lower GSH reduction, to induce the expression of antioxidant genes such as GPx-4, and MnSOD and to suppress inflammatory genes namely COX-2, TNF-α and TGF-β. In addition, the immunomodulatory activity of both the compounds was evident by enhance of the CD4 levels and maintenance of the IgG, IL-6 and IL-10 levels. Persistent treatment (500 μg/kg, for 28 days) with both the compounds showed considerable (p < 0.05) ulcer healing property supporting its role in gastro protection. In conclusion, the results of our study suggest that both SeCys and Ebs possess broad spectrum of activities without any potential toxicity.  相似文献   

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