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1.
The process of galanthamine and related alkaloids production by Leucojum aestivum shoot culture in a temporary immersion system was studied. It was established that temporary immersion approach is prospective for development of a biosynthetic process for obtaining valuable Amaryllidaceae alkaloids. Both immersion frequency and temperature had significant effect on biomass accumulation and the yields of galanthamine and related alkaloids. The maximal yield of galanthamine was achieved at the cultivation of L. aestivum shoot culture in temporary immersion RITA® system at immersion frequency 15 min flooding and 8 h stand-by periods, at 26 °C. Data on the relationships in the biological system “Nutrient medium–L. aestivum shoot culture–galanthamine” are presented as well.  相似文献   

2.
A temporary immersion bioreactor system was found to be suitable for mass shoot proliferation of Rhodiola crenulata. The shoot multiplication ratio and hyperhydration rate reached 46.8 and 35.4%, respectively, at a temporary immersion cycle of 3-min immersion every 300 min. Forced ventilation was employed in the temporary immersion bioreactor culture in order to decrease the hyperhydration rate, improve shoot quality and enhance the multiplication ratio. The highest multiplication ratio of 55.7 was obtained under a temporary immersion cycle of 3-min immersion every 180 min with the forced ventilation at an air flow rate of 40 l/h, and the hyperhydration rate was reduced to 26.1%. Forced ventilation also improved the subsequent elongation and rooting rate of these proliferated shoots, and the shoot cultures from the temporary immersion bioreactor formed complete plantlets when subcultured onto a rooting medium containing 5 μmol/l indole-3-acetic acid.  相似文献   

3.
The present study was carried out to investigate the effect of He?CNe laser irradiations on wheat (Triticum aestivum L.) variety PBW-373 seeds on uptake and internal distribution of zinc ion in wheat plants for different irradiation time in soil culture. The transport of zinc from root system to shoot and grain was studied by incorporating radioactive zinc as zinc chloride (Zn*Cl2) with the nutrient solution to the plants. The 65Zn activity absorbed by the matured plants and distributed in different parts (root, shoot and grain) was measured with a calibrated NaI (Tl) gamma ray spectrometer. The results led the conclusion that translocation of zinc from shoot to grain in mature plants in treated soaked seeds showed a better result in comparison to dry treated and control seeds. The utilization of zinc from roots to shoots was higher in the plants grown from dry seeds in all given treatments and from shoot to grain was best in soaked seeds at 2?min irradiation period.  相似文献   

4.
Repeated batch cultivation (empty-and-fill protocol) using obligate anaerobe Clostridium diolis was attempted in the present study to improve the production of 1,3-propanediol (1,3-PD). In repeated batch operation, 20?% (v/v) culture broth was removed from the bioreactor and supplemented with an equal volume of fresh nutrient medium when the residual glycerol concentration in the bioreactor decreased below 15?g/L. Four cycles of culture broth withdrawal and subsequent replacement resulted in achieving a 1,3-PD concentration of 67.8?g/L with a productivity of 1.04?g/L/h at the end of 65?h. This represented a 1,3-PD concentration and productivity enhancement by 2.6-fold and 1.5-fold, respectively, as compared to batch 1,3-PD fermentation. This is the first report on the use of repeated batch mode of bioreactor operation for enhanced 1,3-PD production.  相似文献   

5.
In order to maximize microalgae biomass production and reduce its overall costs, it is important to optimize inoculum conditions based on its physical and physiological characteristics. Chlorella sorokiniana cultures inoculated with inoculum at three different physiological stages (lag, exponential, and stationary) diluted to the same optical density were cultivated for 12?days under three different CO2 concentrations (0.038, 5, or 10?% CO2 v/v) and growth pattern and biomass production was observed. Samples inoculated with lag phase inoculum supplied with 5?% CO2 achieved the maximum biomass production, whereas samples supplied with 0.038?% CO2 never reached exponential growth. The better growth of samples inoculated with lag phase inoculum was attributed to its increased number of cells compared to the other two inocula.  相似文献   

6.
Batch suspension cultures ofCatharanthus roseus G. Don were grown in a 5 L LKB Ultraferm fermenter, converted to operate as an airlift bioreactor, to test the suitability of such a system for the mass culture of plant cells. Results show that the airlift system has considerable merits as a culture vessel for such a purpose, including: conversion rates of carbohydrate substrate to cell mass equivalent to > 50% under optimum conditions. (Operating under these conditions, growth rates of approximately 0.4 d-1 are typical). In the absence of the mechanical shear normally associated with mechanically driven bioreactors, the gently agitated environment of the airlift vessel proves to be an ideal system for the growth of fragile plant cells. Use of a nozzle sparger reduces the possibility of a high mass transfer coefficient, except at very high gassing rates, thereby eliminating any interference with the growth rate caused by high rates of gaseous exchange.  相似文献   

7.
The present work explores brewery wastewater as a novel substrate for fumaric acid production employing the filamentous fungal strain Rhizopus oryzae 1526 through submerged fermentation. The effects of different parameters such as substrate total solid concentrations, fermentation pH, incubation temperature, flask shaking speed, and inoculum size on the fungal morphologies were investigated. Different morphological forms (mycelium clumps, suspended mycelium, and solid/hairy pellets) of R. oryzae 1526 were obtained at different applied fermentation pH, incubation temperature, flask shaking speed, and inoculum size. Among all the obtained morphologies, pellet morphology was found to be the most favorable for enhanced production of fumaric acid for different studied parameters. Scanning electron microscopic investigation was done to reveal the detailed morphologies of the pellets formed under all optimized conditions. With all the optimized growth conditions (pH 6, 25 °C, 200 rpm, 5 % (v/v) inoculum size, 25 g/L total solid concentration, and pellet diameter of 0.465?±?0.04 mm), the highest concentration of fumaric acid achieved was 31.3?±?2.77 g/L. The results demonstrated that brewery wastewater could be used as a good substrate for the fungal strain R. oryzae 1526 in submerged fermentation for the production of fumaric acid.  相似文献   

8.
Polyhydroxybutyrate or PHB is a biodegradable and biocompatible thermoplastic with many interesting applications in medicine, food packaging, and tissue engineering materials. The present study deals with the enhanced production of PHB by Azohydromonas australica using sucrose and the estimation of fundamental kinetic parameters of PHB fermentation process. The preliminary culture growth inhibition studies were followed by statistical optimization of medium recipe using response surface methodology to increase the PHB production. Later on batch cultivation in a 7-L bioreactor was attempted using optimum concentration of medium components (process variables) obtained from statistical design to identify the batch growth and product kinetics parameters of PHB fermentation. A. australica exhibited a maximum biomass and PHB concentration of 8.71 and 6.24?g/L, respectively in bioreactor with an overall PHB production rate of 0.75?g/h. Bioreactor cultivation studies demonstrated that the specific biomass and PHB yield on sucrose was 0.37 and 0.29?g/g, respectively. The kinetic parameters obtained in the present investigation would be used in the development of a batch kinetic mathematical model for PHB production which will serve as launching pad for further process optimization studies, e.g., design of several bioreactor cultivation strategies to further enhance the biopolymer production.  相似文献   

9.
Contribution of exogenous polyamines (PAs) and polyamine-inhibitors on plantlet regeneration patterns of banana (cv. Nanjanagudu Rasabale-AAB) was studied and the performance of regenerated shoots in temporary immersion system was evaluated. The rhizome explants (without shoot bud) of in vitro shoots produced a mixture of embryogenic and nonembryogenic calli on modified MS medium. The analyses of endogenous pools of polyamines showed higher levels of PAs in embryogenic than in nonembryogenic calli. Supplementation of various levels of (10-50 microM) spermine (Spm), spermidine (Spd), and putrescine (Put) to cultures with secondary embryogenesis showed that about 50% of embryogenic calli rapidly produced secondary embryos only in the presence 40 microM Spm but not in other treatments. The crucial role of Spm was further confirmed by the use of 0.1 mM each of alpha-DL-Difluromethylornithine and alpha-DL-Difluromethylarginine along with Spm where the presence of inhibitors concomitantly inhibited the secondary embryogenesis. The shoots obtained from the embryogenic cultures were checked for their performance on solid medium (SM) and partial immersion system (PIS). The rate of shoot multiplication was higher in PIS than in SM throughout 6 weeks culture period. Uniformity in elongation of all the shoot buds was observed in PIS but not in SM. Evaluation for the acclimatization, survival under greenhouse conditions revealed the better performance of PIS-derived plants than those from SM.  相似文献   

10.
The production of antimicrobial metabolites by Paenibacillus polymyxa RNC-D was assessed. Two process variables, glucose and inoculum concentrations, were evaluated at different levels (5?C40 g L?1, and at ?? r = 2.5?C5.0 %, respectively), and their effects on biomass formation, minimal inhibitory concentration (MIC) against Escherichia coli, and surface tension reduction (STR) were studied. When the fermentation process was carried out under non-optimised conditions, the biomass, MIC, and STR achieved the following values: 0.6 g L?1, 1 g L?1, and 18.4 mN m?1, respectively. The optimum glucose (16 g L?1) and inoculum volume ratio (?? r = 5.0 %) were defined in order to maximise the biomass formation, with a low value of MIC and high STR of extract. The experiments carried out under optimal conditions showed the following values for the dependent variables: biomass concentration 2.05 g L?1, MIC 31.2 ??g mL?1, and STR 10.7 mN m?1, which represented improvement of 241.7 %, 96.9 %, and 41.9 % for the responses of biomass, MIC, and STR, respectively. This is the first recorded study on the optimisation of culture conditions for the production of antimicrobial metabolites of P. polymyxa RNC-D, and constitutes an important step in the development of strategies to modulate the production of antimicrobial molecules by this microorganism at elevated levels.  相似文献   

11.
Using a combination of conventional sequential techniques, the batch growth conditions for the production of cell-envelope-associated proteinases have for the first time been studied and optimised in Lactobacillus delbrueckii subsp. lactis 313 (ATCC 7830; LDL 313). Concentrations of inoculum (0.1?<?X?<?10?% vol/vol), agitation speed (0?<?S?<?200?rpm), varying incubation temperature (30?<?T?<?50?°C), starting pH (4.5?<?pH?<?7) and carbon/nitrogen ratio of production medium (0.2?<?r?<?5) had an individual effect on proteinase yield (p?<?0.01). Optimal conditions for proteinase production included an initial pH of 6.0, 45?°C incubation temperature, 2?% (v/v) inoculum size of OD560?=?1, 150?rpm agitation speed, and growth medium carbon/nitrogen ratio of 1.0. Maximum proteinase activity obtained for whole cells was 0.99 U/ml after 8?h of incubation. The variables studied are very relevant due to their significance in improving the productivity of proteinase synthesis from LDL 313, under process and, likely, economic optimum conditions.  相似文献   

12.
The effects of a new axial impeller (HTPG4) on oxygen volumetric transfer coefficient, K L a, and xylanase production by Penicillium canescens 10-10c were studied and compared for dual-impeller systems, one with one DT4 impeller below and one HTPG4 above (DT4-HTPG4) and one with two DT4 (DT4-DT4) impellers, in a 5-L bioreactor. The volumetric coefficient of oxygen transfer was measured in culture medium using a gassing-out method at different gassing rates and agitation speeds. We observed that the DT4-HTPG4 combination provided better K L a performance than the DT4-DT4 combination. The two combinations were also tested for their influence on xylanase production by a filamentous microorganism; P. canescens 10-10c. These experiments demonstrated that the DT4-HTPG4 combination impeller enhanced enzyme production up to 23% compared with the DT4-DT4 combination at an aeration rate of 1 vvm and an agitation speed of 600 rpm. The main cause for this difference is thought to be a higher shear stress generated by the DT4-DT4 combination, which damages the mycelium of P. canescens and decreases xylanase production.  相似文献   

13.
The bacterial reduction of Cr(VI) from industrial wastewater was evaluated using a 2.0-m3 bioreactor. Liquid pineapple waste was used as a nutrient for the biofilm community formed inside the bioreactor. The use of rubber wood sawdust as packing material was able to immobilize more than 106?CFU?mL?1 of Acinetobacter haemolyticus cells after 3?days of contact time. Complete reduction of 15?C240?mg?L?1 of Cr(VI) was achieved even after 3?months of bioreactor operation. Cr(VI) was not detected in the final effluent fraction indicating complete removal of Cr from solution from the flocculation/coagulation step and the unlikely re-oxidation of Cr(III) into Cr(VI). Impatiens balsamina L. and Gomphrena globosa L. showed better growth in the presence of soil?Csludge mixture compared to Coleus scutellarioides (L.) Benth. Significant amounts of Cr accumulated at different sections of the plants indicate its potential application in Cr phytoremediation effort. The bacterial-based system was also determined not to be detrimental to human health based on the low levels of Cr detected in the hair and nail samples of the plant operators. Thus, it can be said that bacterial-based Cr(VI) treatment system is a feasible alternative to the conventional system especially for lower Cr(VI) concentrations, where sludge generated can be used as growth supplement for ornamental plant as well as not detrimental to the health of the workers.  相似文献   

14.
In this study, different cultivation systems such as roller bottles (RB), 5-L stirred-tank bioreactor (STR), and disposable bioreactors were used to cultivate hybridoma for lab-scale production of Salmonella Enteritidis O-antigen-specific monoclonal antibody (MAb). Hybridoma cell line was cultivated in either serum-containing or serum-free medium (SFM) culture conditions. In STR, MAb production scaled up to 4 L, and production capabilities of the cells were also evaluated in different featured production systems. Moreover, the growth parameters of the cells in all production systems such as glucose consumption, lactate and ammonia production, and also MAb productivities were determined. Collected supernatants from the reactors were concentrated by a cross-flow filtration system. In conclusion, cells were not adapted to SFM in RB and STR. Therefore, less MAb titer in both STR and RB systems with SFM was observed compared to the cultures containing fetal bovine serum-supplemented medium. A higher MAb titer was gained in the membrane-aerated system compared to those in STR and RB. Although the highest MAb titer was obtained in the static membrane bioreactor system, the highest productivity was obtained in STR operated in semicontinuous mode with overlay aeration.  相似文献   

15.
In this study, pumice stone (PS), which is a vastly available material in Turkey, was evaluated as an alternative immobilization material in comparison to other commercially available immobilization materials such as glass beads and polyurethane foam. All immobilized bioreactors resulted in much better 1,3-propanediol production from waste glycerol in comparison to the suspended cell culture bioreactor. It was also demonstrated that the locally available PS material is as good as the commercially available immobilization material. The maximum volumetric productivity (8.5?g?L?1?h?1) was obtained by the PS material, which is 220?% higher than the suspended cell system. Furthermore, the immobilized bioreactor system was much more robust against cell washout even at very low hydraulic retention time values.  相似文献   

16.
An efficient heat shock strategy has been developed to improve laccase production in submerged Trametes versicolor cultures. The optimized heat shock strategy consists of subjecting T. versicolor mycelial pellets to three heat shock treatments at 45?°C for 45?min, starting at culture day?0, with a 24-h interval between treatments. Laccase production increased by more than 1.6-fold relative to the control in both flasks and a 5-L bioreactor because the expression of the laccase gene was enhanced by heat shock induction. The present work demonstrates that heat shock induction is a promising method because it both improves fungal laccase production and has a good potential in industrial application.  相似文献   

17.
Galanthamine‐type alkaloids produced by plants of the Amaryllidaceae family are potent acetylcholinesterase inhibitors. One of them, galanthamine, has been marketed as a hydrobromide salt for the treatment of Alzheimer's disease. In the present work, gas chromatography with electron impact mass spectrometry (GC‐EIMS) fragmentation of 12 reference compounds isolated from various amaryllidaceous plants and identified by spectroscopic methods (1D and 2D nuclear magnetic resonance, circular dichroism, high‐resolution MS (HRMS) and EIMS) was studied by tandem mass spectrometry (GC‐MS/MS) and accurate mass measurements (GC‐HRMS). The studied compounds showed good peak shape and efficient GC separation with a GC‐MS fragmentation pattern similar to that obtained by direct insertion probe. With the exception of galanthamine‐N‐oxide and N‐formylnorgalanthamine, the galanthamine‐type compounds showed abundant [M]+. and [M‐H]+ ions. A typical fragmentation pattern was also observed, depending on the substituents of the skeleton. Based on the fragmentation pathways of reference compounds, three other galanthamine‐type alkaloids, including 3‐O‐(2′‐butenoyl)sanguinine, which possesses a previously unelucidated structure, were identified in Leucojum aestivum ssp. pulchelum, a species endemic to the Balearic islands. GC‐MS can be successfully applied to Amaryllidaceae plant samples in the routine screening for potentially new or known bioactive molecules, chemotaxonomy, biodiversity and identification of impurities in pharmaceutical substances. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

18.
The extracellular lipase of Yarrowia lipolytica presents numerous potentialities for biotechnological applications. This work describes the development and storage of powders obtained from supernatants containing Y. lipolytica lipase by freeze-drying as downstream process that is important in obtaining a stable lipase powder with high enzymatic activity. Lipase was produced by Y. lipolytica U6 mutant strain in 20-L bioreactor. Non-concentrated cell-free culture supernatant samples were supplemented with different concentrations (0.5?C1?%) of maltodextrin and glycerol as additives to freeze-drying. Effects of additives, temperature, pH, and storage time on lipase powders were determined. After addition of additives, freeze-drying yield increased 3.5-fold compared to supernatant without additive. Maltodextrin with 0.5?% concentration gave the best protection of lipase during dehydration treatment and its freeze-drying yield (77?%) is better than other formulations. Lipase powders were stored at 4 and 25?°C for 46?weeks without loss of lipase activity. A common impediment to the production of commercial enzyme is their low-stability aqueous solutions. The present study shows that freeze-dried lipase powders of Y. lipolytica have good stability for storage and various applications.  相似文献   

19.
The present paper studies the biotechnological production of xylitol using sugarcane bagasse hydrolysate in a repeated batch fermentation system with immobilized cells of Candida guilliermondii FTI20037. Immobilized cell system is considered as an attractive alternative to reuse the well-grown and adapted yeast cells in a new fresh fermentation media, without the need of the inoculum stage. In this work, seven repeated batches were performed in a fluidized bed bioreactor using immobilized cells in calcium alginate beads. According to the obtained results it was observed that the immobilized cells of C. guilliermondii can be reused for six successive batches maintaining an average xylitol yield (Y p/s) of 0.7 g/L and a volumetric productivity (Q p) of 0.42 g/L?h at the end of 432 h of fermentation. On the other hand, in the seventh batch (504 h), a decrease of 44 % in the final concentration of xylitol was observed. This reduction can be explained by the possible diffusion and accumulation of insoluble substances, found in the hemicellulosic hydrolysate, in the interior of the immobilization support resulting in substrate mass transfer limitations.  相似文献   

20.
Callus, suspension and bioreactor cultures of Verbena officinalis were established, and optimized for biomass growth and production of phenylpropanoid glycosides, phenolic acids, flavonoids and iridoids. All types of cultures were maintained on/in the Murashige and Skoog (MS) media with 1 mg/L BAP and 1 mg/L NAA. The inoculum sizes were optimized in callus and suspension cultures. Moreover, the growth of the culture in two different types of bioreactors—a balloon bioreactor (BB) and a stirred-tank bioreactor (STB) was tested. In methanolic extracts from biomass of all types of in vitro cultures the presence of the same metabolites—verbascoside, isoverbascoside, and six phenolic acids: protocatechuic, chlorogenic, vanillic, caffeic, ferulic and rosmarinic acids was confirmed and quantified by the HPLC-DAD method. In the extracts from lyophilized culture media, no metabolites were found. The main metabolites in biomass extracts were verbascoside and isoverbascoside. Their maximum amounts in g/100 g DW (dry weight) in the tested types of cultures were as follow: 7.25 and 0.61 (callus), 7.06 and 0.48 (suspension), 7.69 and 0.31 (BB), 9.18 and 0.34 (STB). The amounts of phenolic acids were many times lower, max. total content reached of 26.90, 50.72, 19.88, and 36.78 mg/100 g DW, respectively. The highest content of verbascoside and also a high content of isoverbascoside obtained in STB (stirred-tank bioreactor) were 5.3 and 7.8 times higher than in extracts from overground parts of the parent plant. In the extracts from parent plant two iridoids—verbenalin and hastatoside, were also abundant. All investigated biomass extracts and the extracts from parent plant showed the antiproliferative, antioxidant and antibacterial activities. The strongest activities were documented for the cultures maintained in STB. We propose extracts from in vitro cultured biomass of vervain, especially from STB, as a rich source of bioactive metabolites with antiproliferative, antioxidant and antibacterial properties.  相似文献   

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