433results about How to "Good genetic stability" patented technology

The invention discloses a bacillus licheniformis strain which is preserved as bacillus licheniformis WX-02 with the preserving number of NO: M208065 and the preserving date of April 24th, 2008 and the preserving unit of CCTCC. The invention also discloses an application of the bacillus licheniformis strain and a method for producing poly-gamma-glutamic acid by using the bacillus licheniformis strain. Poly-gamma-glutamic acid products are produced by processes of seed solution preparation and liquid submerged fermentation, and the strain has stable genetic performance of the strain, high production efficiency and low production cost. When the bacillus licheniformis strain of the invention and the fermentation method thereof are used for preparing 3000L of poly-gamma-glutamic acid, the yield of a fermentation tank can reach 35.05g/l.

The invention discloses a recombinant low-virulent vaccine strain of chicken infectious bursal disease viruses (IBDV) and application thereof. In the invention, a major protective antigen gene VP2 of an epidemic superhigh virulent strain is cloned, the nucleotide of the gene VP2 is modified by mutation and then used for replacing a corresponding segment of a Gt genome of a low-virulent strain of the IBDV, so that the infectious clone of a recombinant genome of the IBDV is constructed, and the recombinant low-virulent vaccine strain is saved and identified by using an IBDV reverse genetic operation system. The microbial collection number of the vaccine strain is CGMCC No.3749. The recombinant low-virulent vaccine strain of the invention has high replicability, genetic stability and safety. The immune effect of the low-virulent vaccine strain of the invention is as good as that of the medium-virulent vaccine strain, but is superior to that of the low-virulent vaccine strain. The biological safety of the low-virulent vaccine strain of the invention is superior to that of the medium-virulent vaccine strain. As the vaccine strain, the recombinant low-virulent vaccine strain of the invention has the characteristics of high efficiency and low toxicity, is a good candidate vaccine strain and can be used for controlling chicken infectious bursal disease.

A method for producing a grosvenor momordica tissue culture seedling by a single culture medium uses an MS solid medium during the producing process and is characterized in that the angustimycin of 0.1 to 0.5mg L<1> is added into a normal MS solid medium to produce the grosvenor momordica tissue culture seedling. As the medium singly prepared by the angustimycin can be simultaneously used on each technical tache of 'axillary bud explant starting', 'proliferation and expanding propagation' and 'proliferated seedling rooting', thereby greatly simplifying the producing operation procedures of the grosvenor momordica tissue culture seedling. In particular, the angustimycin can effectively control the generation of a callus during the culturing process of the grosvenor momordica tissue culture seedling in particular, which is beneficial to the genetic stability; thereby improving the quality of the tissue culture seedling.

The invention relates to a method for promoting paeonia suffruticosa seedling growth and application thereof. Specifically, the invention provides a paeonia suffruticosa seedling treatment fluid, which comprises: a paeonia suffruticosa seedling growth active agent (gibberellin and/or 6-benzyladenine) and a surfactant, and also can include an agronomically acceptable soluble calcium salt. The growth active agent can break epicotyl dormancy of paeonia suffruticosa seeds, improve the germination rate/germination potential of paeonia suffruticosa seeds, accelerate the paeonia suffruticosa seed growth process, and promote seedling emergency or flowering of paeonia suffruticosa seed seedlings/tissue culture seedlings. The surfactant can make active substances fully enter cells. And the soluble calcium salt is closely related to multiple physiological functions of cells.

The invention discloses bacillus amyloliquefaciens separated from fermented soya beans and used for producing a protease and belongs to the technical field of biological engineering. The bacillus amyloliquefaciens is separated from traditional fermented soya beans by adopting a separation and purification technique. The bacillus amyloliquefaciens which is identified and named according to the microbial taxonomy is collected in the China Center for Type Culture Collection (CCTCC) on December 10. 2014 with the collection number of CCTCC M 2014639. The bacillus amyloliquefaciens used for producing protease is easy to culture and is highly safe during production, the screened strain for liquid fermenting and culturing has the enzyme activity of 148-2,231U/mL, has good genetic stability; the metabolite is easy to separate and purify; a foundation is laid for the scientific pure culture in the traditional fermented soya bean industry.

The invention discloses a fibrinolytic-enzyme-producing Bacillus amyloliquefaciens strain separated from traditional fermented black beans, belonging to the technical field of bioengineering. The strain is separated and purified from traditional fermented black beans, is named Bacillus amyloliquefaciens by taxonomic identification, and is collected by China Center for Type Culture Collection on December 10th, 2014; and the collection number is CCTCC M2014638. The fibrinolytic-enzyme-producing Bacillus amyloliquefaciens strain is easy to culture, and has the advantages of high production safety and favorable hereditary stability. The enzyme activity of the strain liquid after fermentation and culture is up to 324.6-410.2 IU/mL. The metabolite fibrinolytic enzyme can be easily separated and purified. The separation of the strain lays foundation for implementing scientific axenic culture in traditional fermented black bean industry.

The invention provides a Dioscoreae Oppositae 'Qi' tissue culture seedling raising method, which comprises the steps of explant selection and disinfection, callus tissue induction, adventitious bud differentiation, rooting culture, seedling training, transplanting and the like. By taking the nodular stem segments of the potted Dioscoreae Oppositae 'Qi' as explants, after the explants are disinfected by alcohol with volume concentration of 70 percent and sodium hypochlorite with weigh percentage of 2 percent, the callus tissue induction, the adventitious bud differentiation and the rooting culture are conducted on MS+NAA+BA culture mediums, and rooted seedlings are transplanted in mixed mediums for culture, wherein the mixed mediums comprise vegetable garden soil, mountain sand and peat, with the mass ratio of 4:1:1. Compared with traditional Dioscoreae Oppositae 'Qi' seedling raising methods such as a direct root tuber planting method, a cutting breeding method and the like, the Dioscoreae Oppositae 'Qi' tissue culture seedling raising method has the advantages that the genetic stability of the seedlings is good, the breeding cycle is short, the breeding coefficient is high, the operation is simple and the factory production of the seedlings can be realized. By adopting the method, not only can the problems that the quantity of the used seminal roots for the production of the Dioscoreae Oppositae 'Qi' is large, the cost is high and the characters of strain is degenerated be solved, but also technical supports can be provided for the high quality and high yield and the industrialization of the Dioscoreae Oppositae 'Qi' through large-scale seedling breeding.

The invention discloses a tissue culture method of gynura divaricata. The method comprises the steps of: inductive culture: inoculating on MS start medium without any hormone to induce generation of axillary bud; multiplication culture: inoculating on the medium MS+6BA, 0.2 mg/L+sucrose 20 g/L+ of agar 6 g/L for multiplication; and rooting culture: rooting on MS+IBA 0.1 mg/L+sucrose 20 g/L+agar 6 g/L, or MS+IBA 0.3 mg/L+IAA 0.3 mg/L+sucrose 20 g/L+agar 6 g/L, wherein the culture temperature is 25+/-1 DEG C, the illumination intensity is 20,001x, and the illumination time is 16 h/d. The method disclosed by the invention can quickly and efficiently produce healthy and uniform high-quality gynura divaricata seedlings with pure characteristics at large scale.

The invention relates to a strain for producing L-lysine, which is classified and named as Escherichiacoli NT1003 delta Met delta Thr and is collected in China Center for Type Culture Collection (CCTCC) on May 30, 2013, and the collection number is CCTCC NO: M2013239. The invention further provides a mutation screening method of the strain and a method for producing the L-lysine by utilizing the strain. After continuous passage is performed on the Escherichiacoli NT1003 delta Met delta Thr strain for 7 times, the content of the L-lysine in a fermentation solution is about 60g/L and has no significant change, so that the genetic stability is good.

The present invention relates to a micropropagation method of purple-leaf birch, and relates to a micropropagation method. The invention settles the problems of long breeding cycle, long propagation efficiency, high cost and low survival rate. The method of the invention comprises the following steps: 1. sterilizing the explant; 2. cutting the explant to stem segment, and then executing induction cultivation for obtaining micro-branch; 3. cutting the micro-branch to stem segment and proliferating in the culture medium; and 4. executing invigoration culture to the proliferated micro-branch, sticking into a rooting substrate for executing rooting culture for finishing the micropropagation of purple-leaf birch. The micropropagation method of purple-leaf birch of the invention has the advantages of short propagation period, high efficiency and excellent genetic stability. The propagation efficiency is that the purple-leaf birch propagates for 30-40 times every 30-40 days. The method of the invention also has the advantages of simple operating technique, labor saving, time saving and low cost. The cost is saved by 30%-50% compared with the prior art. Furthermore the rooting rate and survival rate of seedling propagation equally can obtain 100%.

The invention discloses a propagation method of Chinese yam exsomatize, aiming at providing a propagation method of Chinese yam exsomatize with good genetic stability, less propagation usage space, and convenient storage and transportation. The technical scheme of the invention comprises the following steps of: (1) inducing the formation of Chinese yam protocorm; (2) propagating the Chinese yam protocorm; (3) differencing the Chinese yam protocorm; (4) rooting regeneration plant of the Chinese yam protocorm; and (5) hardening and transplanting the regeneration plant of the Chinese yam protocorm. The method is used for the propagation of the Chinese yam.

The invention aims to provide an apple tree valsa ceratosperma transformant and a preparation method thereof. The method comprises the following steps of: after mixing, co-culturing conidial suspensions of agrobacterium tumefaciens containing a binary vector and valsa ceratosperma, screening by using antibiotics to obtain the transformant. According to the method, the conidium of apple tree valsa ceratosperma is used as a receptor, agrobacterium tumefaciens is used as an amboceptor, the problems of difficulty in preparation of protoplast of the apple tree valsa ceratosperma and difficulty in genetic transformation of the valsa ceratosperma caused by low polyethylene glycol (PEG)-mediated transformation efficiency and the like are overcome; the transformation efficiency of the method can be up to 1/10<3> conidiums; simultaneously, the invention provides an apple tree valsa ceratosperma green fluorescent protein (GFP) labelled strain and a preparation method thereof; and the efficiency of the green fluorescent protein with strong expression in the transformant obtained by the method can be up to 96.7%.

The invention belongs to the technical field of forest creatures, and discloses a cultivation method for quickly obtaining lycium ruthenicum regeneration seedlings. The cultivation method comprises the following steps: disinfection of seeds, obtaining of germfree seedlings, induction of a callus, obtaining of adventitious buds and induction of roots. According to the cultivation method, the callus is directly obtained from the germfree seedlings of lycium ruthenicum, and the lycium ruthenicum regeneration seedlings are cultivated through a tissue culture method; compared with a conventional method for inducing the callus through leaves or stems of the seedlings, the cultivation method has the advantages that the tissue culture time is greatly shortened, and cultivation cost of the lycium ruthenicum is greatly reduced; meanwhile, the cultivation efficiency is effectively improved, and the transplanting survival rate of the regeneration seedlings reaches up to 98 percent. The lycium ruthenicum obtained through the cultivation method has the characteristics of being high in genetic stability, low in cost, short in seedling growing period, high in reproduction coefficient, and easy and convenient to operate.