4 results about "Nitrosoguanidines" patented technology

A Penicillium cyclopium strain capable of degrading crop straw fibers efficiently and application thereof are provided. The provided induces mutagenesis of a Penicillium cyclopium strain MP-03 (2554-2) (CGMCC No. 41542) using a nitrosoguanidine method and obtains a mutant strain ΔMP-03 (455-1) (CGMCC No. 41541) with enhanced ability to degrade corn straw. By optimizing a nitrogen-to-carbon ratio of culture medium, culture time, temperature, and a pH range for high enzymatic activity, the mutant strain 455-1 significantly enhances the degradation of corn straw, and endoglucanase and exoglucanase activities in corn straw compared with the non-mutant strain 2554-2. The provided optimizes the conditions for scale-up culture of the mutant strain 455-1, and develops the organic-coupled cultivation technology that integrates a fermentation suspension of the mutant strain 455-1, corn straw and organic fertilizer, which improves the growth, root development and photosynthetic efficiency of greenhouse vegetable, and resistance to the soil-borne oomycete diseases.

The invention belongs to the field of bioengineering, and relates to a method for screening high-yield butanol strains through cyclic compound mutation and application of the high-yield butanol strains, in order to increase the gene diversity of starting strains, the method comprises the following steps: equivalently mixing a plurality of clostridium acetobutylicum strains as the starting strains; taking compound mutagenesis of nitrosoguanidine-acridine orange-nitrosoguanidine-lithium chloride as a cycle, repeating for three cycles, and continuously domesticating the mutagenic flora by gradually increasing the butanol concentration of the culture medium, so as to obtain the mutant flora with high butanol tolerance. And carrying out single colony separation on the mutant flora with high butanol tolerance, measuring the butanol content through fermentation, and screening to obtain the high-yield butanol strain.

This invention discloses a strain of *Bacillus coagulans* that facilitates cell recovery and its application in lactic acid fermentation, belonging to the fields of microbiology and fermentation engineering technology. This invention isolates a batch of thermoresistant bacteria from spoiled milk. After small-scale cell culture, a flocculant is added to observe sedimentation. The strain with the fastest sedimentation rate is selected, and *Bacillus coagulans* is identified among them. Further screening yields a strain, XQ20249, with rapid cell sedimentation and high optical purity of L-lactic acid produced during fermentation. Further mutagenesis using nitrosoguanidine and screening yields mutant strains with even faster cell sedimentation. Among them, mutant strain LL08 shows a significant increase in flocculation and exhibits faster growth and lactic acid fermentation rates than other mutant strains under lactic acid fermentation conditions. When strain LL08 is used for lactic acid fermentation, the cells can be collected by sedimentation after fermentation for secondary fermentation, significantly reducing the amount of organic nitrogen source used.

The invention relates to the technical field of tetramethylpyrazine strain breeding, in particular to a tetramethylpyrazine strain high-throughput breeding device. Comprising a breeding box; a door plate is rotatably mounted on the breeding box, a handle is fixedly connected to the side wall of the door plate, a magnetic strip is embedded in the upper portion of the breeding box, a control panel is mounted on the side wall of the breeding box, ultraviolet lamps which are symmetrically distributed are mounted on the side wall in the breeding box, and a mounting frame is mounted at the bottom in the breeding box. And a mounting groove is formed in the mounting frame. The adding amount of nitrosoguanidine is accurately controlled through the quantitative assembly, the concentration and dosage of a mutagenic agent fed into each adding tank are consistent, the problem that the adding amount of nitrosoguanidine in traditional chemical mutagenesis is difficult to control in a standardized mode is solved, the difference of mutagenesis effects of strains in different batches is effectively avoided, the stability of the positive mutation rate of the strains is guaranteed, and the yield of the strains is increased. And the reliability of chemical mutagenesis is improved.