阅读说明：本技术 一种l-赖氨酸硫酸盐及其副产物的制备方法 (Preparation method of L-lysine sulfate and by-product thereof ) 是由 王成福 唐瑞 于 2019-09-02 设计创作，主要内容包括：本发明公开一种L-赖氨酸硫酸盐及其副产物的制备方法,属于赖氨酸生产工艺技术领域,包括下述步骤：培养基灭菌；发酵,在无菌状态下接入赖氨酸生产菌,发酵过程控制温度为35-40℃、pH值为6.8-7.0和DO值为20-30％,发酵时间为48-60小时；提取和纯化,发酵结束后将赖氨酸和底物混合物放到等电提取车间,用硫酸调发酵液pH值至5-6,经处理的发酵液通过陶瓷膜设备过滤,除去菌体和粘性物质以及渣质,滤后清夜经过三效浓缩,得到浓度20波美的浓缩液,用喷浆造粒床进行造粒干燥,得成品。本发明克服了环保上的难题,减少了生产环节,工艺路线短,原辅料消耗小,成本低,且生产的赖氨酸含量高。(The invention discloses a preparation method of L-lysine sulfate and a byproduct thereof, belonging to the technical field of lysine production process and comprising the following steps: sterilizing a culture medium; fermenting, inoculating lysine producing bacteria under sterile condition, controlling temperature at 35-40 deg.C, pH at 6.8-7.0 and DO at 20-30% during fermentation process, and fermenting for 48-60 hr; extracting and purifying, after fermentation, putting the mixture of lysine and a substrate in an isoelectric extraction workshop, adjusting the pH value of a fermentation solution to 5-6 by using sulfuric acid, filtering the treated fermentation solution by using ceramic membrane equipment to remove thalli, sticky substances and residues, performing triple-effect concentration on the filtered clear solution to obtain a concentrated solution with the concentration of 20 Baume, and performing granulation and drying by using a spray granulation bed to obtain a finished product. The invention overcomes the difficult problem of environmental protection, reduces the production links, has short process route, low consumption of raw and auxiliary materials and low cost, and has high content of produced lysine.)

1. A method for preparing L-lysine sulfate and by-products thereof is characterized by comprising the following steps:

(1) and (3) sterilizing a culture medium: continuously heating the culture medium by using steam so as to kill microorganisms;

(2) fermentation: inoculating lysine producing bacteria under aseptic condition, controlling temperature at 35-40 deg.C, pH at 6.8-7.0 and DO at 20-30% during fermentation, and fermenting for 48-60 hr to maximally accumulate lysine in the metabolic process;

(3) extraction and purification: after fermentation, putting the mixture of lysine and substrate in an isoelectric extraction workshop, adjusting the pH value of fermentation liquid to 5-6 by using sulfuric acid, filtering the treated fermentation liquid by ceramic membrane equipment to remove thalli, sticky substances and residues, performing triple-effect concentration on the filtered clear liquid to obtain a concentrated solution with the concentration of 20 Baume, and performing granulation drying by using a spray granulation bed to obtain a finished product.

2. The method for preparing L-lysine sulfate and its by-products according to claim 1, wherein: the temperature of the steam in the step (1) is 120-130 ℃.

3. The method for preparing L-lysine sulfate and its by-products according to claim 1, wherein: the lysine producing strain is Corynebacterium glutamicum.

4. The method of claim 3 for preparing L-lysine sulfate and its by-products, comprising: the inoculation amount of the lysine producing bacteria is 15-18% of the weight of the culture medium.

5. The method for preparing L-lysine sulfate and its by-products according to claim 1, wherein: the aperture of the ceramic membrane is 50 nm.

Technical Field

The invention relates to the technical field of lysine production processes, and particularly relates to a preparation method of L-lysine sulfate and a by-product thereof.

Background

Lysine (Lysine) has the chemical name 2, 6-diaminohexanoic acid. Lysine is a basic essential amino acid. The cereal is called the first limiting amino acid because of its very low lysine content and its easy destruction and lack during processing.

Lysine is one of the essential amino acids in humans and mammals, and is not synthesized by the body itself and must be supplemented from food. Lysine is mainly present in animal foods and legumes, and lysine content in cereals is very low. Lysine has positive nutritional significance in promoting growth and development of human body, enhancing immunity of organism, resisting virus, promoting fat oxidation, relieving anxiety, promoting absorption of certain nutrients, and can act synergistically with certain nutrients to better exert physiological functions of various nutrients.

The direct fermentation method is a widely used lysine production method. The commonly used raw materials are cheap sugar raw materials such as waste molasses, starch hydrolysate and the like after sugar production of sugarcane or beet. In addition, acetic acid, ethanol, etc. are also optional raw materials. The main microorganisms for producing lysine by direct fermentation method include mutant strains of Corynebacterium glutamicum, Brevibacterium flavum and Brevibacterium lactofermentum. The method is developed in the later 50 th of the 20 th century, and since 70 s, some mutant strains with multiple genetic markers are bred due to the development of breeding technology, so that the process is mature day by day, and the yield of lysine is increased manyfold. The maximum yield of acid in industrial production is improved to 120g per liter of fermentation, and the extraction rate reaches about 80-90%.

Lysine, one of the feed additive materials, plays an extremely important role in feed formulation and nutrient supply. At present, 98 lysine hydrochloride and 70 lysine sulfate are taken as main components in lysine products in markets at home and abroad. 98 lysine hydrochloride, which is produced by ion exchange, has great environmental pollution and high production cost.

Disclosure of Invention

The invention provides a preparation method of L-lysine sulfate and a byproduct thereof, which solves the problems of great environmental pollution and high production cost of the existing direct fermentation production process.

In order to solve the technical problems, the invention is realized by the following technical scheme:

a method for preparing L-lysine sulfate and by-products thereof comprises the following steps:

(1) and (3) sterilizing a culture medium: continuously heating the culture medium by using steam to cause microorganism death;

(2) fermentation: inoculating lysine producing bacteria under aseptic condition, controlling temperature at 35-40 deg.C, pH at 6.8-7.0 and DO at 20-30% during fermentation, and fermenting for 48-60 hr to maximally accumulate lysine in the metabolic process;

(3) extraction and purification: after fermentation, putting the mixture of lysine and substrate in an isoelectric extraction workshop, adjusting the pH value of fermentation liquid to 5-6 by using sulfuric acid, filtering the treated fermentation liquid by ceramic membrane equipment to remove bacteria, viscous substances and residues, performing triple-effect concentration on the filtered clear liquid to obtain concentrated liquid with the concentration of 20 Baume, and performing granulation drying by using a spray granulation bed to obtain a finished product.

Wherein, the temperature of the steam in the step (1) is preferably 120-130 ℃.

Among them, preferably, the lysine-producing bacterium is Corynebacterium glutamicum.

Wherein, the inoculation amount of the lysine-producing bacteria is preferably 15-18% of the weight of the culture medium.

Wherein, preferably: the aperture of the ceramic membrane is 50 nm.

Compared with the prior art, the technical scheme of the invention has the following obvious effects:

in the extraction and purification process, after the pH value is adjusted by sulfuric acid, a ceramic membrane device is adopted for filtering to remove thalli, sticky substances and residues, and the filtered clear solution is subjected to triple-effect concentration.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.