Long-chain dicarboxylic acid (DCA), a building block for synthesizing a variety of high value-added chemicals, has been widely used in agriculture, chemical, and pharmaceutical industries. The global demand for DCA is increasing in recent years. Compared with chemical synthesis which requires harsh conditions and complicated processes, fermentative production of DCA has many unparalleled advantages, such as low cost and mild reaction conditions. In this review, we summarized the chemical and microbial synthesis methods for DCA and the commercialization status of the fermentation process. Moreover, the advances of using molecular and metabolic engineering to create high-yielding strains for efficient production of DCA were highlighted. Furthermore, the challenges remaining in the microbial fermentation process were also discussed. Finally, the perspectives for developing high titer DCA producing strains by synthetic biology were proposed.
Fermentation ; Dicarboxylic Acids/metabolism* ; Metabolic Engineering ; Technology

Plastics are one of the most important polymers with huge global demand. However, the downsides of this polymer are that it is difficult to degrade, which causes huge pollution. The environmental-friendly bio-degradable plastics therefore could be an alternative and eventually fulfill the ever-growing demand from every aspect of the society. One of the building blocks of bio-degradable plastics is dicarboxylic acids, which have excellent biodegradability and numerous industrial applications. More importantly, dicarboxylic acid can be biologically synthesized. Herein, this review discusses the recent advance on the biosynthesis routes and metabolic engineering strategies of some of the typical dicarboxylic acids, in hope that it will help to provide inspiration to further efforts on the biosynthesis of dicarboxylic acids.
Biodegradable Plastics ; Dicarboxylic Acids ; Polymers/metabolism* ; Biodegradation, Environmental ; Metabolic Engineering

OBJECTIVE: This study aimed to clone and characterize the oxiranedicarboxylate hydrolase (ORCH) from Labrys sp. WH-1. METHODS: Purification by column chromatography, characterization of enzymatic properties, gene cloning by protein terminal sequencing and polymerase chain reaction (PCR), and sequence analysis by secondary structure prediction and multiple sequence alignment were performed. RESULTS: The ORCH from Labrys sp. WH-1 was purified 26-fold with a yield of 12.7%. It is a monomer with an isoelectric point (pI) of 8.57 and molecular mass of 30.2 kDa. It was stable up to 55 °C with temperature at which the activity of the enzyme decreased by 50% in 15 min (T₅₀¹⁵) of 61 °C and the half-life at 50 °C (t_{1/2, 50 °C}) of 51 min and was also stable from pH 4 to 10, with maximum activity at 55 °C and pH 8.5. It is a metal-independent enzyme and strongly inhibited by Cu²⁺, Ag⁺, and anionic surfactants. Its kinetic parameters (K_m, k_cat, and k_cat/K_m) were 18.7 mmol/L, 222.3 s^-1, and 11.9 mmol/(L·s), respectively. The ORCH gene, which contained an open reading frame (ORF) of 825 bp encoding 274 amino acid residues, was overexpressed in Escherichia coli and the enzyme activity was 33 times higher than that of the wild strain. CONCLUSIONS The catalytic efficiency and thermal stability of the ORCH from Labrys sp. WH-1 were the best among the reported ORCHs, and it provides an alternative catalyst for preparation of L(+)-2,3-dihydrobutanedioic acid.
Alphaproteobacteria/enzymology* ; Cloning, Molecular ; Dicarboxylic Acids/metabolism* ; Enzyme Stability ; Epoxide Hydrolases/metabolism*

BACKGROUND AND OBJECTIVES: Glutaraldehyde (GA) has been used as a representative method of tissue preservation in cardiovascular surgery. However, GA has showed limited durability including calcification, mechanical failure and toxicity. To overcome those unsolved problems, we analyzed the crosslinking differences of primary amines, GA and genipin in their mechanical and biochemical properties with a single or double crosslinking agent for clinical application. MATERIALS AND METHODS: Samples were divided into 3 groups; control, single crosslinking fixation and double crosslinking fixation after decellurarization using bovine pericardium. For analysis of the biochemical and mechanical properties of each crosslinking method, tensile strength, percentage strain, thermal stability, resistance to pronase, nynhydrin and cytotoxicity test were studied. RESULTS: Combined hexamethylene diamine and suberic acid in the carbodiimide hydrochloride/N-hydroxysucinimide solution (EDC/NHS) after decellurarization, tensile strength and strain percentage were not statistically significant compared to the single crosslinking treated groups (p>0.05). Tissue crosslinking stability was weak in single treatment of diphenylphosphoryl azide, suberic acid, low concentration of EDC, hexamethylene diamine and procyanidin groups, but thermal stability and resistance to the pronase and ninhydrin were markedly increased in concentrated EDC/NHS or after combined double treatment with low concentration of GA or genipin (p<0.001). CONCLUSION: Single or double crosslinking with low concentration of carbodiimide, diphenylphosphonyl azide, procyanidin, suberic acid and hexane diamine were not as effective in mechanical, biochemical, cytotoxic and crosslinking properties compared to GA or genipin fixation, but their mechanical and chemical properties were much improved when combined with low concentrations of GA or genipin in the double crosslinking process.
Amines ; Azides ; Biflavonoids ; Bioprosthesis ; Caprylates ; Catechin ; Dicarboxylic Acids ; Glutaral ; Iridoids ; Ninhydrin ; Pericardium ; Proanthocyanidins ; Pronase ; Sprains and Strains ; Tensile Strength ; Tissue Preservation

Intracellular pH (pHi) has an important influence on the metabolic activity of cells or cellular processes. The intracellular pH (pHi) of long-chain alpha,omega-dicarboxylic acid-producing Candida tropicalis was determined by fluorescence technique using a pH-sensitive fluorescent probe 5(6)-carboxyfluorescein diacetate. Optimal loading conditions of the fluorescent probe into the cells were experimentally determined. Effects of extracellular pH and carbon sources for growth on pHi in the cell grown in a flask were studied; the results indicated that extracellular pH has a slight influence on pHi, whereas carbon sources such as sucrose, glucose, acetic acid, and n-tridecane showed moderate influences. Further work on the relationship between the cell growth activity and pHi was carried out in a 5 L bioreactor. The time course of specific rates of the cell growth, glucose consumption, CO2 production, and pH gradients across cell plasma membrane were plotted, where the cell growth was improved by the higher pHi at 8 - 12 h. The measured pHi values were varied from 5.72 to 6.15 at medium pH 6.0 in which glucose and sodium acetate were used together as carbon source. The investigation of pHi can be helpful for understanding its effects on the kinetics of the metabolic steps involved in the synthesis rate of alpha,omega-dicarboxylic acid and alpha,omega-dicarboxylic acid transport across plasma membranes.
Candida tropicalis ; growth & development ; metabolism ; Culture Media ; Culture Techniques ; methods ; Dicarboxylic Acids ; metabolism ; Hydrogen-Ion Concentration ; Microscopy, Fluorescence

Kidney stone is a highly recurrent disease in the urinary tract system. Most kidney stones are calcium stones, usually consisting of either calcium oxalate or calcium phosphate. Supersaturation of soluble calcium, oxalate, phosphate, and citrate in the urine is the basis for calcium stone formation. Genetics, diet, low physical activity, and individual habits contribute to the formation of kidney stones. In this review, the associations of the risk of kidney stones with oxalate consumption and some individual habits, such as smoking, alcohol drinking, and opium consumption, are summarized.
Humans ; Calcium/urine* ; Oxalates ; Kidney Calculi/urine* ; Calcium Oxalate/urine* ; Habits

PURPOSE: Interest in the augmentation of hair growth for functional and aesthetic purpose has increased dramatically in recent years. Many hair growth products have been released, but most of these have not been proven scientifically. This study aims to measure the hair growth effect of azelaic acid and vitamin B6, which have been known as hair growth materials, in animal models. METHODS: Six weeks old C57BL/6 mice were used in this study and hair of mice were removed by topical treatment. The mice were divided into five experimental groups according to the testing material such as saline (negative control), propylene glycol(vehicle control), azelaic acid, vitamin B6 and azelaic acid plus vitamin B6 in combination. Hair growth was documented photographically and histologically, and then analysed by the high quality hair analysis program system. The quantity of endocrine factors, IGF-I and TGF-beta1 in the skin of mice was measured by PCR analysis. RESULTS: The topical treatment of azelaic acid and vitamin B6 in combination for 2 weeks to dorsal skin accelerated hair regrowth more than other groups. The azelaic acid and vitamin B6-combined treatment also promoted hair follicle elongation and thickness compared to the others. Histologic studies showed increased number of basal cells in azelaic acid and vitamin B6-combined treatment. Furthermore, the azelaic acid and vitamin B6-combined group significantly increased the expression of IGF-I but decreased the expression of TGF-beta1 in the skin of mice compared to other groups. CONCLUSION: These results suggest that azelaic acid and vitamin B6, when used together, have an additive effect and might be used as hair growth materials.
Alkenes ; Animals ; Dicarboxylic Acids ; Hair ; Hair Follicle ; Insulin-Like Growth Factor I ; Mice ; Polymerase Chain Reaction ; Skin ; Transforming Growth Factor beta1 ; Vitamin B 6 ; Vitamins

OBJECTIVETo study chemical constituents from Cynanchum auriculatum.

METHODThe chemical components were isolated and purified by silca gel, sephedex-LH-20 and ODS column chromatography. The chemical structures were elucidated on the basis of physicochemical properties and spectral data.

RESULTThirteen compounds were isolated and identified as: caudatin (1), metaplexigenin (2), cynauricuoside A (3), succinic acid (4), azelaic acid (5), wilforibiose (6), sucrose (7), 1-O-hexadecanolenin (8), beta-amyrin acetate (9), cynanchone A (10), acetylquinol (11), beta-sitosterol (12), daucosterol (13).

CONCLUSIONCompounds 4-9 were obtained from this plant for the first time.

Cynanchum ; chemistry ; Dicarboxylic Acids ; chemistry ; isolation & purification ; Oleanolic Acid ; analogs & derivatives ; chemistry ; isolation & purification ; Plant Tubers ; chemistry ; Plants, Medicinal ; chemistry ; Succinic Acid ; chemistry ; isolation & purification

The skin of Bufo bufo gargarizans, originated from Bufo bufo gargarizans Cantor (Bufonidae), is widely used in traditional Chinese medicine for the treatment of hepatoma, lung cancer and etc. The preparation of the aqueous components has significant therapeutic effect against the digestive tract cancer. The water-soluble chemical constituents in the skin of Bufo bufo gargarizans were then investigated to make clear the active compounds. Six compounds were isolated and purified by recrystallization and column chromatography on silica gel and ODS, their structures were elucidated as 4-amido-3-hydroxymethyl-cyclooctylamidezotetra-alpha-furanone (I), bufogargarizanine C (II), bufothionine (III), dehydrobufotenine hydrobromide (IV), suberic acid (V) and succinic acid (VI) on the basis of physicochemical properties and spectral data (UV, IR, 1H NMR, 13C NMR and MS). Of the above compounds, compounds I and II are new compounds and named bufogargarizanine B and C, respectively.
Animals ; Bridged Bicyclo Compounds, Heterocyclic ; chemistry ; isolation & purification ; Bufo bufo ; Caprylates ; chemistry ; isolation & purification ; Dicarboxylic Acids ; chemistry ; isolation & purification ; Medicine, Chinese Traditional ; Molecular Conformation ; Molecular Structure ; Skin ; chemistry

OBJECTIVETo study the chemical constituents in the root of Cichorium intybus.

METHODThe compounds were isolated and identified by column chromatography and NMR, IR, MS data.

RESULTTwelve compounds were isolated and identified.

CONCLUSION2,3,4,9-tetrahydro-1H-pyrido-(3,4-b)indole-3-carboxylic acid was isolated from the Cichorium genus for the first time, azelaic acid and daucosterol were isolated from the the plant for the first time.

Chicory ; chemistry ; Dicarboxylic Acids ; chemistry ; isolation & purification ; Indoles ; chemistry ; isolation & purification ; Plant Roots ; chemistry ; Plants, Medicinal ; chemistry ; Sitosterols ; chemistry ; isolation & purification