44results about How to "Reduce the chance of mutation" patented technology

The invention discloses a method for producing enramycin by using microbial fermentation. The method comprises the following steps of: preparing spore liquor of streptomyces fungicidicus SDSL1205 CGMCC No. 3933, and preserving the spore liquor under the environment of liquid nitrogen; inoculating the frozen and preserved spore liquor into a seed culture medium to culture seeds so as to obtain seed liquor; inoculating the seed liquor into a fermentation medium for fermenting and culturing according to the inoculum size of between 4 and 6 weight percent; and further processing fermented fermentation liquor to obtain enramycin crystals. The method has the advantages of omitting complicated seed making process, reducing microbiological contamination rate, along with simpleness and practicability, easy control of inoculum size, stable fermentation result and high repeatability. Compared with the conventional process, the method improves the fermentation result to some extent; and the maximum yield of the enramycin is over 8,500 mu g / ml (HPLC).

The invention discloses a method for producing avilamycin by fermenting. The method includes steps of preparing streptomycesolivaceoviridis with inclined surface with spores, connecting spores on the inclined surface to a seed bottle to culture to obtain seed solution, preserving the seed solution in hydraulic hydrogen; inoculating the frozen seed solution to a seed culture medium to culture to obtain the seed solution; inoculating the seed solution to a fermenting culture medium to be subjected to fermenting culture by the inoculation quantity of 5wt%; and further treating the fermented liquid obtained after fermentation to obtain crystals of avilamycin. The method is easy to carry out, completed seed making process is omitted, degeneration is reduced, contamination risk is lowered, inoculation quantity is easy to control, repeatability is good, fermenting results are good, and production cost is low. Further, the fermenting effect is higher than that of the prior art, and the outputof avilamycin can be over 6500 microgram / microliter.

The invention relates to a method for culturing and freezing amniotic mesenchymal stem cells. The culturing method includes amniotic membrane tissue separation, amniotic mesenchymal stem cell separation, P0 generation amniotic mesenchymal stem cell culture and expansion culture. The culture method of amniotic mesenchymal stem cells of the present invention, in the separation stage of amniotic mesenchymal stem cells, adopts a special mixed enzyme digestive solution system (final concentration of each component in the digestive solution: 1.5-2U / mL neutral protease, 0.5mg / mL deoxyribonuclease I and 1mg / mL collagenase IV) for digestion, can more effectively separate amniotic mesenchymal stem cells from amniotic tissue, and then significantly improve the yield of P0 generation cells. The present invention adopts one-step digestion Compared with the traditional two-step digestion method, the operation is more convenient, and the cultured amniotic mesenchymal stem cells have good activity, high yield, high purity, and good repeatability.

The invention discloses a full-ecological vertical cultivation method for dendrobium officinale. The cultivation method comprises the following steps of: selecting planting materials; selecting arenga engleri ropes for binding arenga engleri sheets; selecting the dendrobium officinale; selecting spring water; a planting process: moving pines arranged in matrixes into pits in a leveled greenhouse at intervals of 1.5 m, filling and leveling up the pits with soil, wrapping two-year-old dendrobium officinale domestication seedlings in a bottom-up manner from the bottoms of the pines, and fixing the seedlings on the pines; exposing stems, planting a second circle of the dendrobium officinale domestication seedlings at vertical intervals of 20 cm in a bottom-up manner, and then planting the rest seedlings in the same manner. The full-ecological vertical cultivation method has the beneficial effects that a full-ecological vertical cultivation mode is adopted, the original wild growth strength of the dendrobium officinale is fully released, under the artificial large-area cultivation conditions by modern facilities, the dendrobium officinale can grow mostly close to the wild state, organic production is realized in the whole process and the organic standards are wholly met; in addition, the stability of variety inheritance of the dendrobium officinale can be ensured and the probability of mutation is reduced so as to guarantee pure and good-quality varieties; furthermore, the greenhouse space can be fully utilized for realizing vertical space high-density cultivation and increasing the yield per mu.

The invention discloses a tissue culture and rapid propagation process of Chinese Pistache. The tissue culture and rapid propagation process of Chinese Pistache includes the steps of A, collecting ripe seeds of Chinese Pistache, and removing episperm by sulfuric acid digestion; sterilizing; inoculating the seeds to MS (Murashige and Skoog) minimal medium in which no hormone is added; B, cutting aseptic seedlings into stem segments with buds, removing part of leaves, inoculating to rooting medium or inoculating to enrichment medium prior to transferring to the rooting medium; and C, exercisingand transplanting the tissue culture seedlings. The tissue culture and rapid propagation process of Chinese Pistache has the advantages that the tissue culture method is modified, a medium formula isoptimized, and aseptic seedlings can be obtained easily and can be propagated rapidly and grow healthy and vigorous; mass high-quality test-tube seedlings can be obtained rapidly from the Chinese Pistache which is difficult or slow to propagate under natural conditions and can be applied to culture and production, and variation rate of offspring of the Chinese Pistache obtained by the process is low.

The invention provides a tissue cultivation method of vetiveria zizanioides transplants. The method comprises steps that: sterilizated vetiveria zizanioides explants are placed in induction and proliferation culture media; inducting and proliferation cultivating are carried out concurrently until explants are differentiated and young buds are germinated; times of subcultures are carried out untila required number of seedlings are obtained; the seedlings are transplanted into cultivation media to be cultivated until 3 to 5 roots appear; the seedlings are then transplanted into cultivation bags; routine managements of watering and fertilizing are carried out, and vetiveria zizanioides transplants can be obtained after 40 days of growth. With the method provided by the present invention, usage amounts of drugs can be reduced. Through the concurrent inducting and proliferation cultivating, appearances of variants can be efficiently controlled, tissue cultivating processes can be simplified, propagation periods can be shortened, production cost can be reduced, and merits of vetiveria zizanioides varieties can be kept fast and stably. With the method provided by the present invention, problems in methods with common propagation systems, such as complex parent resources, unstable seedling qualities and slow seedling propagations, can be solved.

A provided dendrobium aphyllum tissue-culture quick propagation method comprises: germination of cracked mature seeds obtained by inbred of dendrobium aphyllum, forming and differentiation of protocorms, rooting culture, culture of complete plants, transplanting and surviving. Compared with conventional propagation methods such as high-position bud cutting or strain segregating, the method provided by the invention employs tissue culture technology for propagation of dendrobium aphyllum, and the tissue culture of dendrobium aphyllum is performed by employing protocorms, so that the propagation speed is fast, a large number of seedlings are obtained and grow well, and thus a large number of dendrobium aphyllum seedlings with same properties are cultured in a short period, the transplanting survival rate is high, the market demand is satisfied, and the method has various advantages such as low cost, short period, high yield and the like.

The invention discloses ginsenoside mixtures and application of the ginsenoside mixtures serving as bidirectional telomere modifiers. The ginsenoside mixture B is composed of ginsenoside Rb1, ginsenoside Rd and ginsenoside Rb3, and the mass ratio of the ginsenoside Rb1, the ginsenoside Rd to the ginsenoside Rb3 is 1-3: 2-3: 1-2. The ginsenoside mixture A is composed of ginsenoside Rg1, ginsenoside Re and ginsenoside Rh2, and the mass ratio of the ginsenoside Rg1, the ginsenoside Re to the ginsenoside Rh2 is 2-3: 1-3: 1-3. The ginsenoside mixture A serves as the telomere prolonging agent, the ginsenoside mixture B serves as the telomere shortening agent, and the ginsenoside mixture A and the ginsenoside mixture B are used jointly so that the plant telomere length can be effectively maintained and the plant life regulation and control can be studied. The ginsenoside mixtures and the application of the ginsenoside mixtures serving as the bidirectional telomere modifiers have important significance for development of novel telomere modifiers and study of the plant life regulation and control.

The invention provides a rapid reproduction method of schlumbergera seedlings. The method comprises the following steps: inoculating a selected, disinfected and sterilized schlumbergera explant onto a culture medium for induction and carrying out synchronous induction and proliferation culture until the explant sprouts and differentiates out a bud; sub-culturing until being proliferated to 3-4 folds, and then transferring to a rooting medium for rooting culture until 3-5 fine roots are grown at the base of a plant; conventionally hardening and then transplanting to a mixed substrate of humus soil, red soil and pearlite; and watering and fertilizing conventionally for growing to obtain the schlumbergera seedlings. In the method, key links in the whole production technical flow of the schlumbergera seedlings are optimized and integrated, the culture medium for induction is blended and bud induction and proliferation culture are carried out synchronously, thus simplifying tissue culture procedure and shortening breeding cycle; and only by adopting two types of the culture media, the bud can be directly formed without callus formation, thus reducing probability of variation occurred on an adventitious bud, effectively controlling generation of a variant strain, being capable of fixing and maintaining fine variety of the schlumbergera seedlings rapidly, improving seedling quality and solving the problems of complicated parental source and unstable quality of the seedlings produced by the conventional breeding system.