16 results about "Sphingomonas elodea" patented technology

The invention belongs to the technical field of molecular biology, and particularly relates to sphingomonas paucimobilis recombinant engineering bacteria as well as a construction method and application thereof. The engineering strain is obtained by knocking out a metabolic bypass gene from sphingomonas paucimobilis, and the metabolic bypass gene is composed of a crtI gene or a phaC gene. The production amount of gellan gum can be increased by the delta phaC knockout strain and reaches 8.9 g / L. In addition, overexpression of energy metabolism related genes pgi or clpB or ycaJ is carried out, and the yield of a strain with the overexpressed pgi gene is increased to the maximum and reaches 9.5 g / L. Therefore, the pgi gene is overexpressed on the basis of the delta phaC knockout strain, the yield of gellan gum is further increased to 10.0 g / L, and the production efficiency is improved.

A composition comprising a pesticide; gellan gum; and a carrier fluid is provided, wherein the gellan gum is present in an amount of 0.001 to 2% by weight, and wherein the carrier fluid comprises water and is present in an amount of 65 to 95% by weight.

This application provides a solid culture medium for the isolation and purification of thermophilic acidophilic bacteria, its preparation method, and its application. The solid culture medium is prepared by mixing a nutrient composition, a coagulant, and deionized water. The coagulant accounts for 9% to 50% of the solid culture medium by mass. The coagulant is a high-acyl gellan gum, containing 3 to 4 acyl groups. The concentration of the high-acyl gellan gum is 5 g / L to 30 g / L. This solid culture medium is made using high-acyl gellan gum. By adjusting the mass percentage of the high-acyl gellan gum, especially by limiting its concentration, the solid culture medium can remain stable for a long time under high temperature and high acid conditions, maintaining good gelation properties. This provides a stable high-temperature and high-acid growth environment for thermophilic acidophilic bacteria, thus facilitating the successful isolation and purification of these bacteria. Furthermore, high-acyl gellan gum is widely available and inexpensive, further reducing culture costs.

The application provides a fermenting beverage of Sparassis and a preparation method thereof, which is prepared by fermenting Sparassis extraction liquid with microcapsules. The microcapsules have an asymmetric structure, one side of which is a dense hydrophobic layer composed of Brazil palm wax, shea kernel oil and microcrystalline cellulose, and the inside of which is embedded with glucose, sodium bicarbonate and glucose oxidase, and the other side of which is a loose hydrophilic layer composed of inulin and a composite gel of gellan gum, and the inside of which is loaded with composite lactobacillus. The microcapsules can protect lactobacillus from the stress of inhibiting components and high viscosity polysaccharides in the extraction liquid in the early stage of fermentation, guarantee the rapid proliferation of the bacterial body, trigger the gas production reaction through the metabolic products, and realize self-driven fermentation. The application effectively breaks the mass transfer barrier, relieves the environmental stress, thereby maintaining the high activity of the bacterial body, and comprehensively improves the fermentation efficiency.

The application provides an optimized CRISPRi / dCas12a gene regulation system of Sphingomonas scs, a recombinant engineering strain and method and application, and specifically belongs to the technical field of genetic engineering. The application provides an optimized CRISPRi / dCas12a gene regulation system of Sphingomonas scs, which comprises a recombinant plasmid carrying a replicon capable of stable replication in Sphingomonas scs, a PJDP promoter driving dcas12a gene transcription, dCas12a a gene, a resistance gene and a crRNA expression cassette. The optimized gene regulation system is a high-efficiency CRISPRi system suitable for S. paucimobilis Based on the optimized gene regulation system, the PHB synthesis pathway can be accurately regulated, the production of gellan gum is improved without affecting the normal growth of the strain, and gellan gum with higher transparency is directly produced.

The invention discloses application of gellan gum to preparation of a preparation for preventing and treating plant bacterial wilt. According to the method, the gellan gum is added into the tomatoes by dissolving and irrigating the roots, the gellan gum can stably resist invasion of ralstonia solanacearum to the roots, the actual prevention and control effect is practically improved, the biocontrol rate of the gellan gum with the concentration of 50 mg / kg is 65.4%, the biocontrol rate of the gellan gum with the concentration of 100 mg / kg is 61.5%, and the method has an obvious prevention and control effect on the ralstonia solanacearum of the tomatoes.

The invention belongs to the technical field of microorganisms, and relates to sphingomonas paucimobilis and application thereof in fermentation production of colorless gellan gum. The sphingomonas paucimobilisQLD24B-15 is named as sphingomonas paucimobilisQLD24B-15, and the preservation number of the sphingomonas paucimobilisQLD24B-15 is CCTCC (China Center for Type Culture Collection) NO: M2025288. The sphingomonas paucimobilis provided by the invention does not generate pigments in the fermentation process, a fermentation product is prevented from being colored, the yield of gellan gum obtained by fermentation is relatively high, and industrialization of fermentation production of colorless gellan gum is facilitated.

The present invention relates to a process for making a pet food composition comprising a red seaweed as a natural gelling agent with enhanced palatability. The compositions of the invention can be devoid of commonly used, chemically treated gelling agents such as carrageenan, alginate, agar, gellan gum.

The invention relates to a gellan gum lyase derived from Sphingomonas elodea, the amino acid sequence of the gellan gum lyase is as shown in SEQ ID NO: 2, and the nucleotide sequence for coding the gellan gum lyase is as shown in SEQ ID NO: 1. On one hand, the gellan gum lyase provided by the invention has degradation activity of gellan gum and can be applied to degradation of gellan gum and preparation of small-molecular gellan gum, the molecular weight distribution width of gellan gum is increased, and a new idea is provided for construction of low-molecular-weight gellan gum production strains; on the other hand, by knocking out the gellan gum lyase gene, a mutant of the Elossphingomonas capable of producing the gellan gum at high yield can be obtained, and a technical support is provided for industrial production of the gellan gum.

The present invention relates to a process for preparing a pet food composition comprising red seaweed as a natural gelling agent with enhanced palatability. The compositions of the invention may be free of commonly used chemically treated gelling agents such as carrageenan, alginate, agar, and gellan gum.

The application belongs to the technical field of bioengineering, and particularly relates to a sphingan oligosaccharide and a preparation method and application thereof. The application provides a sphingan oligosaccharide, the main chain structure of which is beta-L-Rhap-(1→3)-beta-D-Glcp-(1→4)-beta-D-GlcpA, and the sphingan oligosaccharide is obtained by degrading sphingan (Welan gum, gellan gum and diutan gum) by sphingan degrading enzyme SpnR and then purified by liquid chromatography. The sphingan oligosaccharide prepared by the preparation method has mild reaction conditions and is simple to separate. The sphingan oligosaccharide prepared by the application has good plant growth promoting ability and intestinal probiotic effect, and can be used in the fields of agriculture, food, health products and the like, and the application of the sphingan and the sphingan oligosaccharide is expanded.

The present invention belongs to the technical field of microbial culture, and discloses a method and application of facultative anaerobic microbial culture based on a microplate. Method: 1) Gellan gum is mixed with a culture medium, melted, and a suspension culture medium is obtained; the expanded cultured facultative anaerobic microorganisms are diluted with the suspension culture medium to obtain an indicator bacteria suspension; 2) A phosphate solution containing glucose is added to the outermost circle wells of the microplate, an indicator bacteria suspension is added to the inner wells, a glucose oxidase solution is added to the outermost circle wells, the plate is sealed, and the plate is statically cultured. The present invention solves the problem of reading errors caused by edge effects and bacterial sedimentation in traditional microplate culture, significantly improves data reliability, and reduces costs and operational complexity. The method of the present invention is used to detect the activity of antibacterial substances in facultative anaerobic bacteria.

The application discloses a solidified yoghourt containing crystal ball particles and a preparation method thereof, which is mainly prepared from raw milk, crystal ball particles, white granulated sugar, active lactic acid bacteria, Kluyveromyces lactis rennet, calf abomasum enzyme, moringa leaf extract, milk mineral salt, casein micelles and gellan gum, and the addition proportion of each raw material and the addition timing in the preparation process are adjusted, so that the crystal ball particles in the prepared solidified yoghourt can be stably and uniformly suspended and distributed, the change range of the crystal ball position is 0 mm, the maximum difference in the crystal ball data in different positions of the yoghourt can also be stably 1-2, the cohesion can reach more than 13 g, the taste is good, the flavor is good, and better experience can be brought to consumers.

The invention relates to a sphingomonas paucimobilis two-component regulation and control system GelA for regulating and controlling gellan gum synthesis and application of the sphingomonas paucimobilis two-component regulation and control system GelA, and belongs to the technical field of genetic engineering. According to the invention, recombinant plasmids are constructed, strains are knocked out, and backfill strains of the strains are knocked out, so that the effect of a two-component regulation system gelA in regulation of the yield and molecular weight of gellan gum is analyzed; meanwhile, an overexpression strain is further constructed, the yield and molecular weight of gellan gum produced through fermentation of the overexpression strain and an original strain ATCC 31461 are measured, it is found that compared with the original strain, the yield of the gellan gum produced through the overexpression strain is improved by 13.22%, the molecular weight is improved by 44.38%, and the overexpression strain can improve the yield of the gellan gum and improve the yield of the gellan gum. The gellan gum with relatively high molecular weight can be produced, and the method has a very good application prospect.

The present application relates to the field of food technology, and discloses a kind of embedding particles and its preparation method and application.The embedding particles of the present application include from inside to outside: bacterial solution inner core, first colloidal layer, gas layer and solidified second colloidal layer;The colloidal substance in the first colloidal layer includes agar, xanthan gum and gellan gum with mass ratio of (0.5-2):(0.05-1):(1-5);The colloidal substance in the second colloidal layer includes gelatin, sodium alginate and konjac gum with mass ratio of (1-5):(0.05-0.5):(0.5-3);The gas in the gas layer includes nitrogen and carbon dioxide;The diameter of the bacterial solution inner core is 2.0-2.5mm, and the thickness of the first colloidal layer, the gas layer and the second colloidal layer after being solidified by calcium ions is 0.4-0.7mm, 0.3-0.5mm and 0.35-0.65mm respectively.The embedding particles of the present application have novel taste and can protect live bacteria.

The invention relates to an engineering bacterium for producing ultralow molecular weight gellan gum. GelM genes of a gellan gum biosynthetic gene cluster in a genome of the engineering bacterium are knocked out or silenced. The molecular weight of the gellan gum produced by the gelM gene deletion type S.elodea-delta gelM mutant strain constructed according to the invention is about 1 / 9 of the molecular weight of the gellan gum produced by a wild type strain, and the molecular weight of the gellan gum produced by the gelM gene deletion type and gelR gene overexpression strain is about 1 / 132 of the molecular weight of the gellan gum produced by the wild type strain. Compared with a traditional low-molecular-weight gellan gum obtaining mode, the engineering bacterium provided by the invention can be directly fermented and cultured to generate the ultralow-molecular-weight gellan gum, the extraction process of the gellan gum is simplified, and the production cost of the low-molecular-weight gellan gum is greatly reduced.