Sk Innovation Co., Ltd.

Sk Energy Co., Ltd.

Jae Yeon Park

Ki Sung Lee

Tae Young Lee

Joong Min Park

Woo Chan Park

In Ho Cho

Min Su Koo

Outi Koivistoinen

Seung Yeop Lee

Sin Young Kang

Sang Min Lee

Dong Hyun Kim

Jae Wook Ryu

Laura Ruohonen

Marja Ilmen

Young Bin Seo

Merja Oja

Joon Sik Lee

Paula Jouhten

Eun Hee Park

Andrew Conley

Kari Koivuranta

Young Hwan Chu

Disclosed are a recombinant acid-resistant yeast having lactic acid-producing ability and suppressed glycerol production and a method of preparing lactic acid using the same. More particularly, disclosed are a recombinant acid-resistant yeast into which a gene involved in lactic acid production is introduced and in which a gene involved in glycerol production is deleted or attenuated, and a method of preparing lactic acid using the same. When producing lactic acid using the recombinant acid-resistant yeast, the production of lactic acid is maintained while the production of glycerol is reduced, so crosslinking by glycerol can be suppressed in the oligomerization reaction for conversion to lactide, and thus the conversion yield of lactic acid to lactide can be increased.

Recombinant acid-resistant yeast with suppressed glycerol production and method of producing lactic acid using the same

The present invention relates to: acid-resistant yeast to which lactic acid productivity is imparted, and in which the conversion of pyruvate into acetaldehyde is inhibited and, consequently, the ethanol production pathway is inhibited; and a method for producing lactic acid by using same.

Recombinant acid-resistant yeast in which alcohol production is inhibited and method for producing lactic acid by using same

Disclosed are a recombinant acid-resistant yeast having improved lactic-acid-producing ability and a method of preparing lactic acid using the same. When producing lactic acid using the recombinant acid-resistant yeast according to the present invention, not only lactic-acid fermentation can be performed with lactic-acid-producing ability similar to that of bacterial fermentation using a remarkably smaller amount of a neutralizing agent than in the case of conventional bacterial fermentation, but also the production of ethanol and glycerol which are byproducts can be reduced. Thus, fermentation costs can be greatly reduced and the cost of subsequent purification processes can be reduced.

Recombinant acid-resistant yeast having improved lactic-acid-producing ability

The present invention relates to a synthetic promoter capable of controlling the expression of a target gene at various locations in the genome of an acid-resistant strain, and more particularly to a synthetic promoter including a core promoter derived from an acid-resistant strain and an upstream activating sequence (UAS) element serving as an enhancer. When the present invention is applied to a variety of genetic and metabolic engineering techniques for acid-resistant yeast, various metabolic networks can be configured as desired while controlling the expression level of the target gene, so a method of producing various metabolites using acid-resistant yeast is provided, and the cost of producing the metabolites can be greatly reduced depending on the properties of the acid-resistant yeast.

Synthetic promoter based on gene from acid-resistant yeast

Disclosed is a method of producing lactic acid using a recombinant acid-resistant yeast with inhibited lactate metabolism and alcohol production. More specifically, disclosed are a recombinant acid-resistant yeast in which lactate consumption reaction is reduced and which is imparted with lactic-acid-producing ability to thereby exhibit improved lactic-acid-producing ability and reduced ethanol production, and a method of producing lactic acid using the same.

Recombinant acid-resistant yeast with inhibited lactate metabolism and alcohol production and method of producing lactic acid using the same

The present invention relates to a novel promoter for regulating ADH gene expression in an organic acid-resistant yeast, and a method of producing an organic acid by expressing an organic acid production-related gene using the same. When an organic acid production-related target gene is expressed in the organic acid-resistant yeast using the novel promoter according to the present invention, there is an advantage in that the yeast can produce the organic acid with high efficiency while having resistance to the organic acid without inhibiting the growth ability of the yeast.

Promoter derived from organic acid-resistant yeast and method for expression of target gene by using same

The present invention relates to an acid-resistant yeast endowed with a lactic acid production ability and having a suppressed ethanol production pathway, and a method for producing lactic acid using same. According to the present invention, by effectively suppressing the production of ethanol in an acid-resistant yeast, and by expressing an LDH enzyme with strong expression and high efficiency, it is possible to produce lactic acid with high yield even at low pH without degrading growth.

Acid-resistant yeast with suppressed ethanol production pathway and method for producing lactic acid using same

Provided are a recombinant yeast producing 3-hydroxypropionic acid (3-HP) and a method for producing 3-HP using the same, more particularly, a recombinant yeast producing 3-HP, comprising an exogenous AADH gene; an endogenous or exogenous ACC gene; an exogenous MCR gene; and an exogenous HPDH gene, and producing 3-HP through [Pyruvate Acetaldehyde&#x2192;Acetyl-CoA Malonyl-CoA Malonate semialdehyde 3-HP] biosynthesis pathway, and a method for producing 3-HP using the same.

Recombinant yeast producing 3-hydroxypropionic acid and method for producing 3-hydroxypropionic acid using the same

The present invention provides a fed-batch culture method comprising a step of fed-batch-feeding a carbon source base and a base in such a manner that the pH level can be maintained at a level suitable for the growth of microorganisms for fermentation of a carbon source. The present invention also provides a method for preparing organic acids using the fed-batch culture method. The present invention fed-batch-feeds a neutralizing agent such as ammonium bicarbonate, ammonium carbonate or alkali metal-containing weak base, and a carbon source substrate in preparing organic acids by microorganism fermentation. Thus, a pH level suitable for the survival of microorganisms for carbon source fermentation can be maintained, and the speed of injecting the carbon source base which is the source material can be appropriately adjusted. The present invention may improve productivity, yield rate and concentration of organic acids and may automatically inject a base and a carbon source substrate according to a variation in the pH level, thus improving reliability and convenience of a fermentation process operation.

Method for preparing organic acid by fed-batch-feeding carbon source substrate and base

Ball valve

Ejector

Water quality analyzer

Disclosed is a method of preparing alkyl butyrate, which comprises: (a) producing a fermented liquid containing butyrate salt through a fermentation process using butyric acid-producing strains; (b) obtaining an extracted liquid containing butyric acid from a continuous extracting apparatus using an extraction solvent, after converting the butyrate salt into butyric acid by adding an inorganic acid except for carbonic acid or carbon dioxide into the fermented liquid, wherein the continuous extracting apparatus includes a plurality of extraction plates which are installed inside an extraction column and perform a reciprocating motion vertically, and the broth and the extraction solvent are supplied to upper and lower portions of the column, respectively; and (c) reacting the extracted liquid and alcohol having a carbon number of 4 or less or a mixture thereof in an esterification reactor to convert a resultant product into alkyl butyrate. According to the present invention, butyric acid existing in microbic culture fluid can be efficiently extracted, and furthermore, competitively priced alkyl butyrate can be prepared without an additional process of separating the extracted solvent while minimizing energy consumption.

Growing community of inventors

Daejeon, South Korea

Jae Yeon Park