2 results about "Pasteuria" patented technology

The invention discloses a composite microbial inoculant for repairing concrete cracks and a preparation method and application thereof.The composite microbial inoculant is prepared by mixing a sporosarcina pasteurii concentrated solution and an alkali-resistant pseudomonas concentrated solution under the sterile condition, the viable count ratio of the sporosarcina pasteurii concentrated solution to the alkali-resistant pseudomonas concentrated solution is 1: 1-3: 1, and the OD600 value in the mixed concentrated bacterial solution is not lower than 2.0; the total viable bacterium concentration is not less than 109 CFU / mL. During application, the surface of a pre-treated concrete crack is coated with the nutrient salt and a nutrient salt solution with a specific composition. The sporosarcina pasteurii provides urease to quickly hydrolyze urea, creates an alkaline environment and provides CO3 < 2->; the extracellular polymeric substance secreted by the alkali-resistant pseudomonas is used as an additional nucleation site for inducing calcium carbonate deposition, and the crystal is regulated and controlled to grow into a harder calcite type. The complex microbial inoculant can significantly improve the mineralization efficiency, the bonding strength of a film layer and the impermeability, and solves the technical problem that the repair effect of a single strain is limited.

This invention discloses an acid-tolerant Pichia pastoris and its application in succinic acid fermentation, belonging to the field of microbial breeding and fermentation engineering. Firstly, using Pichia pastoris GS115 as the starting strain, this invention constructs an engineered succinic acid-producing strain, GS115-SH, through metabolic engineering. To address the problem of inhibited growth and low succinic acid synthesis efficiency in this strain under acidic conditions, an acidic gradient stress environment from pH 3.8 to pH 3.0 was constructed by progressively lowering the pH of the culture medium using hydrochloric acid. Through continuous subculturing, the bacterial community adapted and solidified under low pH conditions, ultimately resulting in an acid-tolerant acclimatized strain. This strain achieved stable growth at pH 3.0 using glucose as the sole carbon source, with succinic acid production approximately 1.9 times higher than the starting strain; it also exhibited significant acid-producing capacity even without the addition of neutralizing agents such as CaCO3 or NaOH. This invention effectively reduces the amount of neutralizing agent used and simplifies the post-processing procedure, showing promising prospects for industrial application.