57results about How to "Achieve high density culture" patented technology

The invention discloses a device for in vitro high-density cultivation of erythrocyte. The device comprises a stirred tank bioreactor and a hollow fiber cell intercepting device, wherein the structure of the hollow fiber cell intercepting device includes a cylindrical sleeve formed by 4-10 hollow fiber tubes which are parallel to one another; an elastic valve, a piston and a vacuum pump are orderly arranged at the bottom of the cylindrical sleeve; and the upper part of the cylindrical sleeve is connected with the stirred tank bioreactor through a connecting pipe. A method for in vitro high-density cultivation of erythrocyte is also disclosed by the invention. The method comprises the following steps of (1) separating a mononuclear cell; (1) separating CD34+ hematopoietic stem cell; and (3) differentiating the hematopoietic stem cell into the erythrocyte. By using the device and the method, hematopoietic stem cells with different sources can be utilized to carry out in vitro differentiation, so as to form a lot of erythrocytes with complete functions. High-density cultivation of the erythrocytes can be achieved; and the density is improved by about 200 times in comparison with a common cell cultivation method.

The present invention discloses a high density culture method and applications of probiotics. According to the present invention, a porous material is added to a culture medium containing a growth promoting factor for promoting the growth and the breeding of probiotics, a volume ratio of the culture medium to the porous material is 1:0.001-1:1000, and probiotics are inoculated in the culture medium and culturing is performed so as to achieve the high density culture of the probiotics; the obtained probiotics can be used for preparing food, food additives, medicines, feeds or environmental protection treatment, and other products; and the obtained high-density probiotics have advantages of good heat resistance, good acid resistance , good drug resistance and other performances, and have wide application prospects in food, medicines, feeds, environmental protection, and other fields.

The invention discloses a method of yeast fermentation coproduction ergot sterol and glutathion, utilizing conspecific yeast bacterial fermentation to produce simultaneous two kinds of metabolite-ergot sterol and glutathion, the utilization bacterial of fermentation is Saccharomyces cerevisiae, candida utilis, candida tropicalis or engineering bacterial reconstructed by mutagenesis and gene engineering, the utilization yeast culture medium contain the carbon source such as glucose, cereal mash, sucrose molasses and so on, the nitrogen source such as maize milk, yeast powder, protease leather, carbonyldiamide, ammonia and so on, inorganic salt and the metallic ion that the yeast need. The invention utilizes fermentation coproduction ergot sterol and glutathion, simultaneously, accomplish high-density culture of the yeast cell, and make the biomass of yeast expression coproduction come up to the standard of the high level in individual fermentation ergot sterol and glutathion, full utilization culture medium substrate, increasing availability ratio of raw material, decreasing the cost of manufacture.

The invention relates to a method for producing polypeptide antibiotics enramycin by the fermentation method, which pertains to the fields of agricultural biotechnology, industrial biotechnology and the fermentation engineering. The method is as follows: (1) slant culture: a Streptomyces sp.NJWGY3665 bacterial strain is inoculated in a glucose nutrient culture medium to carry out the slant culture, the culture temperature is 28 to 37 DEG C and the culture time is 2 to 6 days; (2) seed culture: a spore which is cultured on a slant is produced into a single-spore suspension by using sterile water, which is also inoculated in a seed culture medium for culture, the temperature is 28 to 32 DEG C, the rotational speed is 200rpm and the culture lasts for 2 to 6 days; (3) fermentation culture: the seed liquid is inoculated in a fermentation culture medium for culture, the temperature is controlled at 28 to 37 DEG C, the pH is controlled at 6.0 to 9.0, the rotational speed is 180 to 220rpm, the fermentation lasts for 5 to 9 days, so as to obtain the Streptomyces sp., methanol or ethanol is used for the extraction and separation of mycelium through the method of centrifugal separation, then the resin method is adopted for carrying out refining, so as to obtain the peptide antibiotics enramycin.

The invention discloses a screening purification and scale breeding method for thermocyclops. The method is characterized in that copepods groups are captured from a river mouth on the border between salt water and fresh water or a breeding pond to serve as germplasm sources for screening; under the setting condition, the thermocyclops is directionally screened, and a thermocyclops population with a certain density is obtained by breeding; scale continuous breeding is carried out on the thermocyclops under the optimization breeding conditions that the temperature is 21.3 DEG C, the salinity is 12.46, and the light intensity is 65.6 Lux, two thirds of total thermocyclops individuals are caught every three days, and the fact that 90-100 thermocyclops individuals are bred in per liter water is formed through three weeks of breeding. The screening purification and scale breeding method for the thermocyclops has the advantages that purebred high density breeding can be carried out, the bred fleas biology living bodies are moderate in size, not only is full of nutrients and can be directly used as food sources, but also can be used as initial feeding of larvas such as economic fish, shrimps and crabs.

The invention discloses bacillus subtilis cultured by biochar and a preparation method and an application thereof. The preparation method takes biochar as an adsorption carrier, such as wood chips, animal bones, plant rhizomes and other biochar, takes any kind of bacillus subtilis strains as a starting strain, and successively comprises the following steps: (1) test tube expanding culture; (2) liquid shake flask culture; (3) seed tank expanding culture; (4) fermentation culture; and (5) drying. The bacterial density of the bacillus subtilis prepared by the method can reach 5*10<13>-1*10<15> cfu / mL. The biological adsorption and the liquid fermentation are in organic combination, the bacterial density of the liquid fermentation is improved, no any additional equipment is added, continuous culture and semi continuous culture are not used, and the high-density culture of the bacillus subtilis is achieved; and the cultured bacillus subtilis can be used as a live bacterial agent of a biofertilizer or used as a live bacterial agent of the biofertilizer with other strains.

The invention discloses a high-density culture method for a yeast, and belongs to the field of yeast fermentation. Through a two-stage feeding mode combining index feeding and dissolved oxygen feedback pulse fed-batch feeding, the yield of a by-product ethyl alcohol is effectively controlled to be at a low level, the utilization ratio of a molasses raw material is improved, meanwhile, the yeast can be ensured to be quickly proliferated to high concentration, the dry cell weight of yeast cells can reach to 123.6g.L<-1>, the yield of yeast mycelium is improved, 0.51g of dry strain can be obtained at most per gram of sugar, and the productivity of small and medium-sized enterprises is favorably improved on the basis of the original scale.

The invention relates to the technical field of biological fermentation, and discloses a method for producing Chinese caterpillar fungus mycelium powder through fermentation. The method comprises thespecific steps that by means of slant strain culture, shake flask seed culture, first-stage seed tank and second-stage seed tank culture and fermentation tank culture, a mature fermentation solution is placed in tanks according to 80%-90% v / v of the fermentation volume, then a fermentation medium is added into the tanks until the original fermentation volume is reached, culture continues to be carried out, and 6-8 tanks are continuously cultured in the same way. According to the method, the defects that when the Chinese caterpillar fungus mycelium powder is produced through liquid fermentation, the period is long, and the yield is low are overcome, and the method is practical to industrialization of Chinese caterpillar fungus mycelium.

The invention belongs to the technical field of biology, and particularly relates to a ST culture medium and application thereof. The ST culture medium does not contain serum, fully-suspended serum-free culture of ST cells can be realized by adopting the ST culture medium, and high-density culture can be realized without using a microcarrier. The serum is not needed in the process of suspended culture of the ST cells, and the culture medium does not contain animal-derived components, so that batch-to-batch difference and the safety problem caused by the animal-derived components like the serumare eliminated, production cost is lowered, and the downstream separation and purification step is simplified. In addition, components in the culture medium are determined, so that repeatability andstability from supply of the culture medium to cell culture to product production.

The invention discloses a production process for fermenting trichoderma spp by taking orange peels as raw materials, which belongs to the technical field of microorganisms. The production process comprises the following steps: (1) preprocessing: drying, grinding and sieving the orange peels; (2) mixing preprocessed orange peel powder with wheat bran and de-ionized water according to a certain ratio, and sterilizing by high-pressure steam; (3) inoculating trichoderma onto a sterilized material for solid-state fermentation; (4) drying a solid fermentation product to obtain a trichoderma preparation product. The trichoderma spp preparation produced by the process has capabilities of promoting plant growth and inducing plants to resist adversity and diseases, can be used for preventing and treating soil-borne diseases and promoting repair of plants in polluted soil, and provides a new way for resource utilization of the orange peels.

The invention relates to a synthesis method for 4-hydroxyisoleucine. The method comprises the following steps: firstly, constructing recombinant expression plasmids for expressing L-isoleucine-4-hydroxylase and L-glutamate oxidase simultaneously; adding two types of substrates including L-glutamic acid and L-isoleucine into a constructed catalytic reaction system; taking the substrates as precursors of a catalytic reaction and synthesizing the 4-hydroxyisoleucine. After the catalytic reaction is performed for 4h, the conversion rates of the L-glutamic acid and the L-isoleucine are 97.01 percent and 98.45 percent respectively. By replacing alpha-ketoglutaric acid with the L-glutamic acid and utilizing the L-glutamic acid as the precursor for synthesizing the 4-hydroxyisoleucine, the 4-hydroxyisoleucine can be efficiently produced, the production cost is low and industrial production is convenient to realize.

The invention discloses an efficient culture medium for chlorella. The efficient culture medium for the chlorella comprises the following components per liter: (1) major elements: 0.10-0.20g of sodiumnitrate, 0.01-0.04g of potassium dihydrogen phosphate, 0.02-0.08g of magnesium sulfate heptahydrate, 0.02-0.06g of urea, 0.01-0.04g of calcium chloride, 0.01-0.05g of sodium bicarbonate and 0.50-1.5gof sodium chloride; (2) microelements: 2.00-5.00mg of ferric citrate, 0.05-0.10mg of copper sulfate pentahydrate, 2.00-3.00mg of boric acid, 1.50-2.00 mg of tetrahydrate manganese chloride and 0.10-0.40 mg of sodium molybdate dihydrate; and the balance of seawater. The efficient culture medium for the chlorella can be directly added and applied, so that the chlorella can quickly absorb various nutrients in a liquid medium in a short time, thereby realizing high-density culture, and achieving faster growth rate and higher yield; at the same time, the cost of buying agar powder is saved, thereby reducing the production cost.

The invention provides a light organism reaction device which can be used for culturing cell suspension of microalgae and other photosynthetic organisms. The light organism reaction device comprises a turbulence type multilevel spherical reactor, a reactor constant-temperature sleeving, a circulation diversion pipe, a circulation diversion pipe constant-temperature sleeving, a settling tank, a gap inlet, a gas distributor, a feeding opening, a light source, a constant-temperature waterbath, a gas flowmeter and the like. The light organism reaction device is a semicontinuous circulation gas lifting type light organism reactor, the cell suspension rises in the reactor in a turbulent mode in the flashing environment, and constant temperature cultivation can be achieved. The light organism reaction device has the advantages of being moderate in cultivation, good in liquid mixing, high in gas-liquid mass transfer intensity, low in shear force, quick in growth, intensive in biological cell density, capable of being harvested continuously and the like, so that the light organism reaction device has a high economic value and a high industrial application prospect.

The invention provides a production method of an encephalitis B vaccine, which comprises the following steps: adding Vero seed cells to a 300-liter bioreactor, and carrying out perfusion culture together with a microcarrier; after the perfusion culture is carried out for 5-6 days, depositing the microcarrier and the cells, replacing a culture medium with a main medium, vaccinating encephalitis B viruses, and continuously carrying out the perfusion culture; and collecting a virus culture solution, filtering, inactivating and purifying the virus culture solution. By using the method, the density of the cells for production is improved; the production capacity is improved greatly; the large-scale and high-density culture is achieved; the difference between batches of products and the instability of a culture period are eliminated; the quality of the products is guaranteed to be stable and uniform; the product quality is improved; the difficult problems of the amplification culture process of the bioreactor are solved; the high-density and large-scale culture of mammalian cells by using the bioreactor is achieved.

The invention discloses a method for large-scale high-density suspension culture of a cell 293-high yielding adenovirus. The method comprises the steps of firstly, carrying out serum-free 293SFM culture, then, starting CD culture medium culture to produce a virus, combining a perfusion technology and a cutoff technology, and meanwhile, controlling temperature changes of cell culture and viral infection. According to the method, the enlarging of cell culture density is achieved, the volume of cell culture is reduced, subsequent labor intensity is lowered, the yield of the virus is increased, the cost is reduced, the cell death loss of a cutoff process is reduced, the quality is uniform and stable during culture, a production process is close in link and easy in control, and thus, stable quality of batches is guaranteed.

The invention discloses an animal cell hollow fiber culture system and a cell culture method thereof. The system comprises a hollow fiber cylinder, a liquid storage system, circulating systems (an inner circulating system and an outer circulating system) and a detection control system. The hollow fiber cylinder performs culture medium circulation through the inner circulating system; and the outercirculating system is used for cell inoculation and cell digestion, uniform distribution of cells among hollow fibers is achieved through circulation of a peristaltic pump in the outer circulating system, and the cell inoculation uniformity is improved. Conditions similar to in-vivo growth are established, and the culture effect is good. An alternate positive pressure circulating system (mode) isadopted to guarantee alternate replacement of nutrient components in hollow fiber inner and outer systems, and the problems that hollow fibers are blocked and the dead volume of a nutrient solution cannot be replaced are also avoided. Meanwhile, the system is of a closed design, is good in biological safety, can effectively control pH, dissolved oxygen and temperature in the culture process, andis suitable for animal cell culture in vaccine and antibody production.

The invention relates to a device and a method for culturing microalgae in a large scale, in particular to a cylinder-shaped thin film reactor device for fast culturing the microalgae. In the cylinder-shaped thin film reactor device, a main body is a vertical steel structure cylinder-shaped or polygonal cylinder bracket, the upper end and the lower end of the bracket are formed by a plurality of stainless steel metal straps arranged in a circular shape through welding, and the cylinder-shaped or polygonal cylinder bracket is arranged in a rectangular formation or a square formation. The lower end of the cylinder-shaped thin film reactor is opened, a pipe is arranged at the position of an opening, the pipe and a thin film are integrated to be a closed structure, the pipe is of a screw structure, the reactor is directly sleeved on the base of the cylinder-shaped bracket, and the upper end of the reactor is provided with an exhaust port, a feed port and an inlet port. A top cover of the reactor is installed and fixed at the upper end of the cylinder-shaped bracket so that direct impact of rainwater, and the like and attachment of dust can be avoided. The base of the cylinder-shaped bracket is provided with the opening, the opening is of the screw structure and can be connected with the pipe of the opening at the lower end of the thin film reactor, and raw material belts are filled in connection position of the opening and the pipe for closing.

The invention provides a lactic acid bacteria fermentation medium for feed and a preparation method thereof, belonging to the technical field of microorganisms, wherein the fermentation medium comprises whey protein hydrolysate obtained by acid hydrolysis of whey protein with inulin. The preparation method of fermentation medium comprises: preparing whey protein hydrolysate: carrying out acid hydrolysis on whey protein added with inulin; and mixing the resulting whey protein hydrolysate, yeast powder, glucose, buffer salt, Mg<2+> water-soluble compound, Fe<2+> water-soluble compound, and MnSO4. As that fermentation medium of the invention can prevent the damage of oxygen to the feed lactic acid bacteria, more ATP is provided for the feeding lactic acid bacteria, the growth requirement ofthe fermentation medium for the feed lactic acid bacteria is prolonged, the acid stress resistance and the propagation quantity of the feeding lactic acid bacteria are improved, and high-density culture is realized. The whey protein hydrolysate prepared by the preparation method of the invention comprises D Type amino acids and flavoring amino acids.

The invention provides a method for supplementing material in the fermentation process of transglutaminase, in particular to a method for supplementing dissolved oxygen in the fermentation process of transglutaminase, comprising the steps of fermenting Streptomyces hygroscopicus CCTCC M203062 for 8-16 hours; adding a mixed solution of 800 g / L of glucose and 800-1200 g / L of peptone having a carbon-nitrogen ratio of 1.0-1.5 to the fermentation system through flowing so as to control the specific growth rate to be 0.15 1 / h and 16-24 h; then adding the mixed solution through flowing to control the specific growth rate to be 0.10 1 / h. The method, on the one hand, avoids the nitrogen source being cross-linked by transglutaminase to affect the oxygen dissolution in the fermentation process, and on the other hand, increases the biomass of the bacteria through addition of nitrogen source by means of flowing. The method has obvious effect so that the biomass is increased by 125-140% and the enzyme activity is increased by 58-63%.

A marine algae culture device comprise a culture pool, an aeration system, an internal circulation system, an additional light source, a temperature control system and a dirt discharging port; the aeration system is positioned at the bottom of the culture pool and comprises a fan, an aerator and an aeration pipe; the internal circulation system comprises a water discharging pipe, a purification system and a water inlet pipe; the additional light source is positioned at the top of the culture pool; the temperature control system comprise a temperature control rod and a control box; the temperature control rod is positioned on the middle part of the culture pool; the temperature control rod is connected with the temperature control box; and the dirt discharging port is positioned at the bottom of the culture pool. The invention also provides a method for performing algae culture by applying the device. The method comprises the following steps: pretreating algae seedlings to obtain algaeseedlings 1; putting the obtained algae seedlings 1 into the culture pool to perform cultivation to obtain algae seedlings 2; and performing intermittent aeration and secondary cultivation on the obtained algae seedlings 2 to obtain mature algae. The light utilization rate is high, the temperature is controllable, influence by the external environment is avoided, high-density culture can be realized, and technical support is provided for large-scale cultivation of marine algae in China.

The invention discloses a method of yeast fermentation coproduction ergot sterol and glutathion, utilizing conspecific yeast bacterial fermentation to produce simultaneous two kinds of metabolite-ergot sterol and glutathion, the utilization bacterial of fermentation is Saccharomyces cerevisiae, candida utilis, candida tropicalis or engineering bacterial reconstructed by mutagenesis and gene engineering, the utilization yeast culture medium contain the carbon source such as glucose, cereal mash, sucrose molasses and so on, the nitrogen source such as maize milk, yeast powder, protease leather, carbonyldiamide, ammonia and so on, inorganic salt and the metallic ion that the yeast need. The invention utilizes fermentation coproduction ergot sterol and glutathion, simultaneously, accomplish high-density culture of the yeast cell, and make the biomass of yeast expression coproduction come up to the standard of the high level in individual fermentation ergot sterol and glutathion, full utilization culture medium substrate, increasing availability ratio of raw material, decreasing the cost of manufacture.

The invention relates to a rapid culture method of chrysophyceae. The culture method is heterotrophic culture; a culture medium contains a carbon source and a nitrogen source; the carbon source is glucose; the nitrogen source is a mixed carbon source composed of an organic nitrogen source and an inorganic nitrogen source; the organic nitrogen source is selected from one or more of liver extract powder, beef extract, yeast extract powder and peptone; the inorganic nitrogen source is ammonium nitrogen or urea. In a culture process, a material supplementation culture medium is supplemented into afermentation tank; the temperature of a culture system in the fermentation tank is controlled to be 20 to 30 DEG C, the pH (Potential of Hydrogen) is 5.0 to 8.0, the dissolved oxygen concentration is10 to 60 percent and the concentration of glucose is stabilized to be 0 to 2g / L; a nitrogen-containing material supplementation culture medium is supplemented from the beginning of the culture to a first moment, and a nitrogen-free material supplementation culture medium is supplemented from the first moment to a second moment or the ending of the culture; a basic culture medium contains vitaminB1, BH, B6 or B12 or the vitamin B1, BH, B6 or B12 is added into the fermentation tank in a culture process. According to the method provided by the invention, after the culture is carried out for 96to 170h, the highest biomass can reach 56g / L and the growth of the chrysophyceae is remarkably accelerated after the vitamin B1, BH, B6 or B12 is added.

The invention relates to a high-density and large-scale diatom carrier culture technique which comprises the steps that many kinds of seaweed meal serve as carriers; 0.001-50% of seaweed meal is added to seawater; an appropriate amount of nutritive salt is added; a diatom seed solution is inoculated; natural or artificial light is adopted; the diatom is cultured at a natural temperature of 30 DEGC for 2-30 days; and ventilation or agitation is performed appropriately in a culture process. Diatom is attached to the surface of seaweed, grows and propagates. After the culture, a seaweed and diatom mixture is separated and obtained by separation methods such as natural settling, filtering and centrifugation, contains more than thirty million diatom cells per gram in wet weight, and can serve as fresh and alive fish bait to be fed directly. The separated seawater can be used for the culture next time directly after the nutritive salt, the seaweed meal and the diatom seed solution are added. The culture technique is convenient and easy to implement, and is applicable to reactor culture and large-scale pond culture of benthic diatom; high-density fresh and alive diatom biomass can be obtained; and the alive diatom cells serve as feed to be fed, and can exert a function of improving a substrate environment.

The invention discloses a method for improving the fermentation yield of plasmids, which comprises the following steps: after fermenting for a certain time by using a primary fermentation culture medium, carrying out exponential fed-batch fermentation at a limited specific growth rate by using a fed-batch culture medium A so as to improve the yield of escherichia coli plasmids. According to the method for increasing the fermentation yield of the plasmids, by optimizing the material supplementing culture medium and the material supplementing method, high-quality and high-yield plasmid DNA can be obtained more quickly and more conveniently, high-density culture of escherichia coli is achieved, the plasmid yield is increased, and meanwhile the integrity of the plasmids can be kept.

The invention relates to the technical field of biotechnology and food processing, in particular to an apple-flavored beverage and a preparation method thereof. The method comprises the following steps: soaking apple peel pomace in a citric acid solution, preparing a culture medium, carrying out first-stage aspergillus niger fermentation, crushing aspergillus niger cells, performing homogenizing,and carrying out second-stage probiotic fermentation. In the prior art, apple peel pomace contains a large amount of cellulose, pectin and other macromolecular substances, is difficult to use, pollutes the environment if discarded, and is difficult to degrade by a single microorganism. The invention provides the preparation method of the apple-flavored beverage. The apple peel pomace is soaked ina citric acid solution, browning can be prevented, productive turnover is facilitated, aspergillus niger and probiotics are fermented in different stages, products in a first stage are utilized through two-stage fermentation, the finally prepared apple-flavored beverage has the advantages of being high in living cell number of the probiotics and the like, and waste utilization of the apple peel pomace is achieved.

The invention provides a positive displacement conveying tube type photobioreactor which is composed of a positive displacement transmission system, a photosynthetic reaction system and supporting accessories.The positive displacement transmission system is composed of a gear, a transmission shaft, a motor, a sealing plug, a chain, an inlet cone and an upper water tube, wherein the gear is driven to rotate by the motor, an alga solution in the upper water tube is conveyed into the photosynthetic reaction system in a sectioned and sealed mode through the sealing plug via chain transmission, and a power source is provided for circulation of the alga solution.The photosynthetic reaction system comprises photosynthetic reaction tube sections, a water distribution trough, a water trough, a connecting tube and a water outlet tube.Unit combination rotors are installed in the photosynthetic reaction tube sections, and a reaction site is provided for a photosynthetic reaction of microalgae.The supporting accessories include a motor rack, a gear supporting plate and a supporting frame, and support and fix the whole system.According to the positive displacement conveying tube type photobioreactor, microalgae cells are protected against harm of pump shearing force, and high-density culture of microalgae can be easily achieved; the number of the photosynthetic reaction tube sections connected to the water distribution trough can be adjusted according to flow, the flow speed and the culture scale, the structure is flexible, and adaptability is high.

The invention discloses a pipeline type photobioreactor for culturing microalgae in multiple nutrition modes. The pipeline type photobioreactor comprises a plurality of groups of reaction units and acirculating unit, wherein each reaction unit comprises front and rear rows of transparent pipelines; the circulating unit comprises a buffer tank and a circulating pump, wherein the buffer tank comprises a tank body, a cover body and a heating jacket, a heating device is also arranged in the heating jacket, and a pH sensor and a temperature sensor are arranged in the tank body; a discharge headerpipe is arranged at the bottom of the tank body, the discharge header pipe communicates with an inlet of the circulating pump, an outlet pipeline of the circulating pump is divided into feeding branches, and the feeding branches communicate with feeding ports of the reaction units; a material collecting pipeline is arranged on each feeding branch; a discharge hole of each reaction unit communicates with the circulating main pipe through a discharge pipeline; the circulating header pipe communicates with the buffer tank; a discharge branch pipe is also arranged on the discharge header pipe; a breather valve, an inoculation port, a carbon dioxide pipeline, a nutritive salt supplementing pipeline and a turbidity testing pipeline are arranged on the cover body; and the turbidity testing pipeline communicates with a turbidity detection device.

A pouring culture method of hematopoietic cells in stirring type bioreactor includes suspending the hematopoietic cells in culture medium, inoculating to stirring-type bioreactor, culturing continuously pouring the culture medium in the bioreactor, flowing the cultured liquid in a settling device, intercepting the living cells, and returning then back to the bioreactor. Its advantage is high amplification efficiency.