10 results about "Antibiotic free" patented technology

The present application belongs to the field of synthetic biology and functional food technology, and provides a swallowing safety-oriented xanthan gum directional biosynthesis method. In view of the problem that existing xanthan gum is difficult to reduce the risk of swallowing residue and aspiration by relying on viscosity regulation alone, a multi-dimensional evaluation system combining interfacial tribology and extensional rheology is established to determine the side chain modification parameters suitable for swallowing disorder food. By chromosome scarless reconstruction of xanthan gum synthesis gene cluster, the gumF 、 gumG gene is knocked out and the gumL promoter is replaced, an engineering strain without antibiotic resistance gene residue and with genetic stability is constructed, and directional synthesis of xanthan gum with specific side chain structure is realized. The obtained structure customized xanthan gum has a lower mucosal interfacial friction coefficient and a more optimal extensional rheological property, and can synergistically realize interfacial lubrication and bolus cohesion, significantly reducing the wall residue in the pharynx, and keeping the consistency stable in complex food matrix. The present application can provide a safe, stable and industrialized functional xanthan gum raw material for swallowing disorder food.

The application discloses application of eugenol in preparation of a bacteriostatic agent for enhancing symbiotic nitrogen fixation efficiency of legume-rhizobium, and relates to the field of agricultural microorganisms. ‑1 The application is safe and non-inhibiting to seed germination of Medicago polymorpha and target rhizobium LL2 in a concentration range of 500-1000 muL / L ‑1 of eugenol, can significantly reshape rhizosphere microbial community structure by selectively inhibiting competitive microorganisms such as bacillus and streptomyces in soil, and is environment-friendly and free of antibiotic residue risk, thereby providing a green and efficient new approach for improving symbiotic nitrogen fixation efficiency of legume-rhizobium.

The application discloses a traditional Chinese medicine feed additive for preventing and treating Simmental respiratory disease syndrome and a preparation method and application thereof, and belongs to the technical field of livestock feed additives. The additive is prepared from traditional Chinese medicine raw materials, such as ephedra, honeysuckle, forsythia, radix scrophulariae, radix houttuyniae, radix isatidis, platycodon, bitter apricot kernel, radix glycyrrhizae, radix astragali, rhizoma atractylodis, mint, loquat leaf and radix codonopsis, through decocting, extracting, low-temperature extracting after mint, concentrating and spray drying. The application adopts a three-step prevention and treatment strategy of 'dispelling lung-evil, clearing heat and resolving toxin and supporting healthy body', can effectively prevent and adjuvantly treat Simmental respiratory disease syndrome caused by mixed infection of multiple pathogens, significantly reduces the morbidity of calf BRDC, enhances the immune function of the body, promotes growth and weight gain, has the characteristics of no antibiotic residue, no drug resistance, good palatability and the like, and meets the requirements of green and healthy breeding.

The application relates to a traditional Chinese medicine and additive compound preparation for treating gizzarditis of laying hens and application, and relates to the technical field of veterinary drugs. The compound preparation is prepared by mixing a traditional Chinese medicine extract and a functional feed additive. The raw material composition of the traditional Chinese medicine extract comprises torrefied malt, torrefied medicated leaven, radix codonopsis, rhizoma atractylodis macrocephalae, rhizoma coptidis, andrographis, dried tangerine or orange peel, white arillus, and liquorice. The additive comprises neutral protease, a mould inhibitor and probiotics. The mould inhibitor is selected from aspergillus flavus B1 degrading enzyme, corn strobukenone degrading enzyme, fumonisin degrading enzyme and vomitoxin degrading enzyme. The probiotics are selected from lactobacillus plantarum, bacillus subtilis and fructo-oligosaccharide. The application is based on the traditional Chinese veterinary theory of food digestion and spleen health, dampness expelling and qi regulation, heat clearing and toxin resolving and mucosa repairing. In combination with the effects of the additive on digestion, mould expelling and intestinal micro-ecological regulation, the application has a remarkable treatment effect on gizzarditis of laying hens, can improve the feed intake and weight gain, reduce the gizzard index, promote the repair of gastric mucosa, and has no antibiotic residue and no toxic side effect.

Antibiotic-free systems for maintaining plasmids in host cells and methods of using same. The plasmids can comprise one or more plasmid-maintenance genes and a gene of interest configured to express in the host cell. The one or more plasmid-maintenance genes can comprise one or more of a prophage repressor gene, a sucrose phosphorylase gene, and an alcohol / aldehyde dehydrogenase gene. The methods can comprise growing the host cell with the plasmid comprised within the host cell, wherein the plasmid can be maintained during growth in the host cell without the use of antibiotics. In systems with a plasmid comprising a sucrose phosphorylase gene, the methods can comprise growing the host cell in the presence of sucrose as a sole carbon source. In systems with a plasmid comprising an alcohol / aldehyde dehydrogenase gene, the methods can comprise growing the host cell in the presence of glucose as a sole carbon source.

This invention proposes a compound plant composition for inhibiting intestinal inflammatory response in pigs, its preparation method, and its application, relating to the field of veterinary technology. The compound plant composition contains the following active ingredients in parts by weight: 50-70 parts carvacrol, 10-20 parts thymol, 30-50 parts cinnamaldehyde, 5-10 parts baicalein, 5-10 parts apigenin, and 3-8 parts chlorogenic acid. The preparation method involves mixing the active ingredients in proportion, adding water and Tween-80, and stirring until homogeneous. This invention can significantly reduce the levels of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α in the serum and small intestinal tissue of pigs infected with enterotoxigenic Escherichia coli, and increase the level of the anti-inflammatory cytokine IL-10. It also exerts its anti-inflammatory effect by inhibiting the activation of the TLR4-MyD88-NF-κB signaling pathway. This invention uses a compound of natural plant extracts, eliminating the risk of antibiotic resistance and veterinary drug residues, and is simple to prepare.

This invention provides a recombinant plasmid for expressing the Bacillus subtilis resistance marker gene without antibiotic resistance, its construction method, and its application. This invention utilizes Bacillus subtilis SCK6 supercompetent cells to directly construct a Bsggt recombinant expression plasmid that does not contain the Ori replication origin site of Escherichia coli or the ampicillin resistance gene. This results in a smaller free plasmid expression system, providing a stable expression tool for heterologous proteins in production applications. The use of Cas9n-AID base editing technology in this invention simplifies the strain screening process. The constructed resistance marker-free expression plasmid is smaller than traditional shuttle plasmids, and no inducing agent is needed during expression. Because the expression plasmid is free of antibiotic resistance markers, the growth rate is significantly increased during culture due to the absence of antibiotic pressure. High expression without antibiotic introduction is more suitable for food safety-grade production applications.