65results about How to "Improve sugar-acid conversion rate" patented technology

The invention discloses an L-ammonium lactate tolerant bacterial strain and an application thereof in producing L-ammonium lactate through fermentation. According to the invention, low-energy nitrogen ions are injected in mutant original strains, and then the strains are screened by using a high-sugar tablet, a succinic acid tablet and an ammonium lactate tablet so as to obtain high-sugar-resistant and EMP approach reinforced strains which do not decompose and use a lactic acid. In a 3L fermentation tank, the strains are subjected to cultivation and acclimatization in a culture medium filled with critical-concentration ammonium lactate, and a bacteria liquid subjected to acclimatization of 72 hours is used as an original bacteria liquid of the next mutagenesis and acclimatization. The process is repeated until a target strain (Lactobacilluscasei) LC-An226 is screened. The strain has the characteristics of good ammonium lactate tolerance and high saccharic acid conversion rate. In a 5L fermentation tank, the output of L-ammonium lactate in the fermentation liquor reaches 206 g / L, and increased by 58.46% compared with the production of L-ammonium lactate by using original strains through fermentation, therefore, the strain has great social significance and economic values.

The invention relates to the field of microbial fermentation, and particularly discloses a method for producing D-lactic acid through fermentation. The method comprises the following step: inoculatinga fermentation culture medium with at least part of a carbon source provided by saccharification liquid against Lactobacillus plantarum with a preservation number of CGMCC No.16835. A production method of the saccharification liquid comprises the steps of mixing a slurry containing a starchy raw material and amylase for spray liquefaction, then conducting flash evaporation, cooling and heat preservation, and then mixing liquefaction liquid and a saccharifying enzyme for saccharification; the dosage of the saccharification liquid makes a content of carbon in the fermentation culture medium equal to 60-80 g / L; and conditions of lactic acid fermentation comprise a temperature of 37-45 DEG C, a pH value of 5.3-6.5, the time of 40-60 h, and the rotating speed of stirring of 50-150 rpm, and theinoculation quantity of the Lactobacillus plantarum makes Lactobacillus plantarum OD600 in a lactic acid fermentation system after inoculation is conducted range from 0.3 to 1. According to the method for producing the D-lactic acid through fermentation, the adopted raw materials have the characters of being wide in source and low in cost, by means of the provided method, production can be conducted in a wide pH value range and a wide temperature range, the workload of raw material pre-treatment is reduced, and the method for producing the D-lactic acid through fermentation has the charactersof being high in sugar utilization rate and conversion rate and short in production cycle.