Embodiments of the present invention are directed to processes for the production of (R)-3-hydroxybutyl (R)-3-hydroxybyrate. Poly (R)-3-hydroxybyrate is transesterified with an alcohol, to form a first ester portion and a second ester portion. The first ester portion is reduced to the diol to form a diol portion and the diol portion is reacted with the second ester portion to produce (R)-3-hydroxybutyl (R)-3-hydroxybyrate.

Embodiments of the present invention are directed to processes for the production of (R)-3-hydroxybutyl (R)-3-hydroxybyrate. Poly (R)-3-hydroxybyrate is transesterified with an alcohol, to form a first ester portion and a second ester portion. The first ester portion is reduced to the diol to form a diol portion and the diol portion is reacted with the second ester portion to produce (R)-3-hydroxybutyl (R)-3-hydroxybyrate.

Methods of microbial screening for identifying alcohol acyltransferases for ester biosynthesis and submodules for ester pathways to produce butyryl-coenzyme A derived esters are disclosed. The method includes the introduction preselected plasmids into a respective host strain to form engineered microbes, in situ fermentation thereof followed by a colorimetric assay for quantification of production of the target ester. In situ fermentation includes inoculating each well of a microplate that have a culture media for producing target esters with one of the engineered microbes, adding an overlay of a solvent to each, and incubating the same. The colorimetric assay includes transfer of a quantity of the overlay from each well to respective clean wells of a new microplate, treatment of each well to form an iron-hydroxamic acid complex aqueous phase, centrifugation of the microplate, and measurement of the absorbance at 520 nm and comparison to a standard curve for the target ester.

Methods of microbial screening for identifying alcohol acyltransferases for ester biosynthesis and submodules for ester pathways to produce butyryl-coenzyme A derived esters are disclosed. The method includes the introduction preselected plasmids into a respective host strain to form engineered microbes, in situ fermentation thereof followed by a colorimetric assay for quantification of production of the target ester. In situ fermentation includes inoculating each well of a microplate that have a culture media for producing target esters with one of the engineered microbes, adding an overlay of a solvent to each, and incubating the same. The colorimetric assay includes transfer of a quantity of the overlay from each well to respective clean wells of a new microplate, treatment of each well to form an iron-hydroxamic acid complex aqueous phase, centrifugation of the microplate, and measurement of the absorbance at 520 nm and comparison to a standard curve for the target ester.

A process can be used for enzymatic preparation of sorbitan carboxylates. Sorbitan carboxylates are obtainable by this process.

The present invention provides a carbonyl reductase having the activity of reducing a carbonyl group-containing compound to convert the compound into an optically active compound, and a production method of an optically active compound using the enzyme. Specifically, a carbonyl reductase having one or more mutations in which the 54th aspartic acid, the 157th methionine, the 170th alanine, the 211th isoleucine, the 214th methionine, and the 249th methionine are each substituted by other specific amino acid in the amino acid sequence shown in SEQ ID NO: 1 or a homologue of the amino acid sequence, and a production method of an optically active compound using the same are provided.

The present invention is related to a novel enzymatic process for production of retinoids via a multi-step process, which process includes the use of heterologous enzymes having activity in a carotene-producing host cell, particularly wherein such process results in high percentage of retinoids, in trans-isoform.

The present invention is related to a novel enzymatic process for production of retinoids via a multi-step process, which process includes the use of heterologous enzymes having activity in a carotene-producing host cell, particularly wherein such process results in high percentage of retinoids, in trans-isoform.

Provided herein are methods for generating cellular biomass in continuous aerobic fermentation systems. The biomass yield, and the concentration of polyhydroxyalkanoate within the biomass, are each directed to advantageous levels by operating the continuous fermentation system under particular nutrient limitation conditions. Also provided are biomass produced using the provided methods, and animal feed compositions including the provided biomass.

The present disclosure discloses Stenotrophomonas pavanii capable of degrading polyethylene terephthalate, belonging to the technical field of microorganisms. The present disclosure provides a S. pavanii strain JWG-G1 capable of degrading polyethylene terephthalate (PET). After a seed solution of the S. pavanii is inoculated into an inorganic salt liquid medium containing 2 g/L polyethylene terephthalate at an inoculum size of 10% (v/v) and cultured for 5 d, polyethylene terephthalate (PET) particles can be partially degraded into monohydroxyethyl terephthalate and terephthalic acid that can be directly recycled. In addition, ester bond functional groups on the surface of the polyethylene terephthalate plastic particles can be reduced, and a weight loss rate of the polyethylene terephthalate plastic particles can reach 9.4%. Therefore, the S. pavanii JWG-G1 of the present disclosure has very high application prospects in the degradation of polyethylene terephthalate.