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Acetate ester compounds find widespread use in various applications such as surface coatings, ink formulations, pharmaceuticals, and adhesives. It is essential to investigate the phase transition behavior of amyl acetate, amyl acetoacetate, and isoamyl acetoacetate in high-pressure supercritical CO2 (SC-CO2). The vapor-liquid equilibria (VLE) of the SC-CO2 + amyl acetate, SC-CO2 + amyl acetoacetate, and SC-CO2 + isoamyl acetoacetate systems were examined at different temperatures (313.2 ≤ T ≤ 393.2 K) and pressures (1.67 ≤ P ≤ 20.76 MPa). The solubility curve of these systems shows Type-I phase behavior, and the critical points of these binary mixtures were observed between the critical properties of the pure components involved in the systems. The solubility of amyl acetate, amyl acetoacetate, and isoamyl acetoacetate in the SC-CO2 + amyl acetate, SC-CO2 + amyl acetoacetate, and SC-CO2 + isoamyl acetoacetate systems increases with increasing temperature at constant pressure. The two-parameter model of Peng-Robinson equation of state along with a mixing rule, accurately correlated the phase transition behavior and critical mixtures curves for all three systems. The binary interaction parameters (BIPs) were adjusted, and the minimum root mean square deviation percentage was identified for all three systems. The calculated error% was found to be within reasonable limits, with values of 4.95 %, 3.93 %, and 4.18 % for SC-CO2 + amyl acetate, SC-CO2 + amyl acetoacetate, and SC-CO2 + isoamyl acetoacetate systems, respectively. Furthermore, the interaction parameters for the SC-CO2 + amyl acetoacetate mixture was found to be temperature-dependent, and the tested linear regression correlation coefficient for the BIPs parameters of (kij) and (ηij) are 0.98533 and 0.99083, respectively. This is the first research study on the phase behavior of acetate ester compounds in SC-CO2 solvents, and the results have a significant impact on industries at different operating conditions.

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Acetate ester compounds find widespread use in various applications such as surface coatings, ink formulations, pharmaceuticals, and adhesives. It is essential to investigate the phase transition behavior of amyl acetate, amyl acetoacetate, and isoamyl acetoacetate in high-pressure supercritical CO 2 (SC-CO 2). The vapor-liquid equilibria (VLE) of the SC-CO 2 + amyl acetate, SC-CO 2 + amyl acetoacetate, and SC-CO 2 + isoamyl acetoacetate systems were examined at different temperatures (313.2 ≤ T ≤ 393.2 K) and pressures (1.67 ≤ P ≤ 20.76 MPa). The solubility curve of these systems shows Type-I phase behavior, and the critical points of these binary mixtures were observed between the critical properties of the pure components involved in the systems. The solubility of amyl acetate, amyl acetoacetate, and isoamyl acetoacetate in the SC-CO 2 + amyl acetate, SC-CO 2 + amyl acetoacetate, and SC-CO 2 + isoamyl acetoacetate systems increases with increasing temperature at constant pressure. The two-parameter model of Peng-Robinson equation of state along with a mixing rule, accurately correlated the phase transition behavior and critical mixtures curves for all three systems. The binary interaction parameters (BIPs) were adjusted, and the minimum root mean square deviation percentage was identified for all three systems. The calculated error% was found to be within reasonable limits, with values of 4.95 %, 3.93 %, and 4.18 % for SC-CO 2 + amyl acetate, SC-CO 2 + amyl acetoacetate, and SC-CO 2 + isoamyl acetoacetate systems, respectively. Furthermore, the interaction parameters for the SC-CO 2 + amyl acetoacetate mixture was found to be temperature-dependent, and the tested linear regression correlation coefficient for the BIPs parameters of (k ij) and (η ij) are 0.98533 and 0.99083, respectively. This is the first research study on the phase behavior of acetate ester compounds in SC-CO 2 solvents, and the results have a significant impact on industries at different operating conditions. [Display omitted] • Investigated the phase behavior of acetate esters in SC-CO 2 at various temperatures. • Each system's solubility increased with increasing temperature at constant pressure. • The Peng-Robinson model accurately predicted the phase equilibrium curve. • Validated the Type-I phase behavior and critical mixture points of all systems. • The new findings of the systems can benefit the industrial separation processes. [ABSTRACT FROM AUTHOR]

Short-chain esters, particularly isobutyl acetate and isoamyl acetate, hold significant industrial value due to their wide-ranging applications in flavors, fragrances, solvents, and biofuels. In this study, we demonstrated the biosynthesis of acetate esters using Yarrowia lipolytica as a host by feeding alcohols to the yeast culture. Initially, we screened for optimal alcohol acyltransferases for ester biosynthesis in Y. lipolytica. Strains of Y. lipolytica expressing atf1 from Saccharomyces cerevisiae, produced 251 or 613 mg/L of isobutyl acetate or of isoamyl acetate, respectively. We found that introducing additional copies of ATF1 enhanced ester production. Furthermore, by increasing the supply of acetyl-CoA and refining the culture conditions, we achieved high production of isoamyl acetate, reaching titers of 3404 mg/L. We expanded our study to include the synthesis of a range of acetate esters, facilitated by enriching the culture medium with various alcohols. This study underscores the versatility and potential of Y. lipolytica in the industrial production of acetate esters., (© 2024 American Institute of Chemical Engineers.)

This study determined the impact of temperature on fermentation and sensory characteristics of imo‐shochu, prepared at a laboratory scale by fermentation and distillation of moromi (a mixture of rice‐koji, sweet potato and water). In accordance with the typical temperature regime used by shochu makers, the maximum temperature of moromi during fermentation was controlled at 25, 32, or 38°C. After distillation, the characteristics of the imo‐shochu were determined by sensory evaluation and gas chromatography–mass spectrometry. In the moromi fermented at 25°C, the yeast population after fermentation was two‐fold larger, but CO2 productivity was 40% lower than when fermented at higher temperatures. Conversely, the concentration of acetic acid and amino acids were highest in the moromi fermented at 38°C. Shochu fermented at 25°C was rated as the fruitiest by sensory evaluation. It contained more esters (phenethyl acetate and ethyl caproate) and more higher alcohols and fatty acids. Shochu fermented at 38°C had the most acidic odour. This was consistent with the higher acetic acid levels in the moromi. Shochu fermented at 32°C had the sweetest and richest taste. Accordingly, fermentation temperature was found to be a critical factor for fermentative quality and flavour characteristics of imo‐shochu. © 2021 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Background Green organic solvents such as lactate esters have broad industrial applications and favorable environmental profiles. Thus, manufacturing and use of these biodegradable solvents from renewable feedstocks help benefit the environment. However, to date, the direct microbial biosynthesis of lactate esters from fermentable sugars has not yet been demonstrated. Results In this study, we present a microbial conversion platform for direct biosynthesis of lactate esters from fermentable sugars. First, we designed a pyruvate-to-lactate ester module, consisting of a lactate dehydrogenase (ldhA) to convert pyruvate to lactate, a propionate CoA-transferase (pct) to convert lactate to lactyl-CoA, and an alcohol acyltransferase (AAT) to condense lactyl-CoA and alcohol(s) to make lactate ester(s). By generating a library of five pyruvate-to-lactate ester modules with divergent AATs, we screened for the best module(s) capable of producing a wide range of linear, branched, and aromatic lactate esters with an external alcohol supply. By co-introducing a pyruvate-to-lactate ester module and an alcohol (i.e., ethanol, isobutanol) module into a modular Escherichia coli (chassis) cell, we demonstrated for the first time the microbial biosynthesis of ethyl and isobutyl lactate esters directly from glucose. In an attempt to enhance ethyl lactate production as a proof-of-study, we re-modularized the pathway into (1) the upstream module to generate the ethanol and lactate precursors and (2) the downstream module to generate lactyl-CoA and condense it with ethanol to produce the target ethyl lactate. By manipulating the metabolic fluxes of the upstream and downstream modules through plasmid copy numbers, promoters, ribosome binding sites, and environmental perturbation, we were able to probe and alleviate the metabolic bottlenecks by improving ethyl lactate production by 4.96-fold. We found that AAT is the most rate-limiting step in biosynthesis of lactate esters likely due to its low activity and specificity toward the non-natural substrate lactyl-CoA and alcohols. Conclusions We have successfully established the biosynthesis pathway of lactate esters from fermentable sugars and demonstrated for the first time the direct fermentative production of lactate esters from glucose using an E. coli modular cell. This study defines a cornerstone for the microbial production of lactate esters as green solvents from renewable resources with novel industrial applications.

Flavor production by esters or by higher alcohols play a key role in the sensorial quality of fermented alcoholic beverages. In Saccharomyces cerevisiae cells, the syntheses of esters and higher alcohols are considerably influenced by intracellular CoA levels catalyzed by pantothenate kinase. In this work, we examined the effects of cofactor CoA and acetyl-CoA synthesis on the metabolism of esters and higher alcohols. Strains 12α−BAP2 and 12α+ATF1 where generated by deleting and overexpressing BAP2 (encoded branched-chain amino acid permease) and ATF1 (encoded alcohol acetyl transferases), respectively, in the parent 12α strains. Then, 12α−BAP2+CAB1 and 12α−BAP2+CAB3 strains were obtained by overexpressing CAB1 (encoded pantothenate kinase Cab1) and CAB3 (encoded pantothenate kinase Cab3) in the 12α−BAP2 strain, and 12α−BAP2+CAB1+ATF1 and 12α−BAP2+CAB3+ATF1 were generated by overexpressing ATF1 in the pantothenate kinase overexpression strains. The acetate ester level in 12α−BAP2 was slightly changed relative to that in the control strain 12α, whereas the acetate ester levels in 12α−BAP2+CAB1, 12α−BAP2+CAB3, 12α−BAP2+CAB1+ATF1, and 12α−BAP2+CAB3+ATF1 were distinctly increased (44–118% for ethyl acetate and 18–57% for isoamyl acetate). The levels of n-propanol, methyl-1-butanol, isopentanol, isobutanol, and phenethylol levels were changed and varied among the six engineered strains. The levels of acetate esters and higher alcohols can be modulated by changing the CoA and acetyl-CoA levels. The method proposed in this work supplies a practical means of breeding yeast strains by modulating acetate ester and higher alcohol production. [ABSTRACT FROM AUTHOR]

Graphical abstract Five diiron ethanedithiolate complexes [Fe 2 (CO) 5 (L){μ-SCH 2 CH(CH 2 O 2 CCH 3)S}] (L = P(2-C 4 H 3 O) 3 , 2 ; P(2-C 4 H 3 S) 3 , 3 ; P(4-C 6 H 4 F) 3 , 4 ; P(4-C 6 H 4 Cl) 3 , 5 ; Ph 2 PC 6 H 11 , 6) containing acetate ester and phosphine ligands were prepared by CO substitution. The complexes 2 – 6 have been characterized by elemental analysis, IR and NMR spectra, as well as by X-ray crystallography. Moreover, the electrochemical properties were also studied. Abstract A series of acetate ester containing diiron ethanedithiolate complexes have been synthesized and structurally characterized. CO substitution of complex [Fe 2 (CO) 6 {μ-SCH 2 CH(CH 2 O 2 CCH 3)S}] (1) with the phosphine ligands tris(2-furyl)phosphine, tris(2-thienyl)phosphine, tris(4-fluorophenyl)phosphine, tris(4-chlorophenyl)phosphine, or cyclohexyldiphenylphosphine in the presence of the decarbonylating agent Me 3 NO·2H 2 O gave the phosphine-substituted diiron derivatives [Fe 2 (CO) 5 (L){μ-SCH 2 CH(CH 2 O 2 CCH 3)S}] (L = P(2-C 4 H 3 O) 3 , 2 ; P(2-C 4 H 3 S) 3 , 3 ; P(4-C 6 H 4 F) 3 , 4 ; P(4-C 6 H 4 Cl) 3 , 5 ; Ph 2 PC 6 H 11 , 6) in 86–95% yields. The complexes 2 – 6 have been characterized by elemental analysis, spectroscopy, and X-ray diffraction analysis. Additionally, the electrochemical properties were investigated by cyclic voltammetry. [ABSTRACT FROM AUTHOR]

Five diiron ethanedithiolate complexes bearing acetate ester have been prepared and characterized. Esterification of complex [{ μ -SCH 2 CH(CH 2 OH)S}Fe 2 (CO) 6 ] ( 1 ) with acetic acid in the presence of N , N ′-dicyclohexylcarbodiimide and 4-dimethylaminopyridine gave the acetate ester [{ μ -SCH 2 CH(CH 2 O 2 CCH 3 )S}Fe 2 (CO) 6 ] ( 2 ) in 94% yield. Further treatment of complex 2 with a monophosphine ligand triphenylphosphine, tricyclohexylphosphine, tris(2-methoxyphenyl)phosphine or tris(4-tolyl)phosphine in the presence of Me 3 NO·2H 2 O resulted in the formation of the corresponding monophosphine-substituted diiron derivatives [{ μ -SCH 2 CH(CH 2 O 2 CCH 3 )S}Fe 2 (CO) 5 L] (L = PPh 3 , 3 ; PCy 3 , 4 ; P(C 6 H 4 OCH 3 -2) 3 , 5 ; P(C 6 H 4 CH 3 -4) 3 , 6 ) (Cy = cyclohexyl) in 69–87% yields. The complexes 2 – 6 were characterized by elemental analysis and spectroscopy, together with X-ray crystallography. Furthermore, the electrochemical properties were investigated by cyclic voltammetry. [ABSTRACT FROM AUTHOR]

Acetate esters and higher alcohols significantly determine the flavor profiles of Chinese Baijiu (Chinese liquor). The aminotransferase encoded by BAT2 and alcohol acetyltransferases encoded by ATF1, ATF2, and Lg-ATF1 are involved in the production of branched-chain alcohols and synthesis of acetate esters, respectively. In this study, the effects of ATF1, ATF2, and Lg-ATF1 overexpressions with BAT2 deletion were explored in Chinese Baijiu yeast. The differences among these effects were also investigated. Results showed that the productions of acetate esters by mutant overexpressing ATF1 with BAT2 deletion and that overexpressing ATF2 with BAT2 deletion were 1353.45 and 73.40 mg/L, respectively, which were 43.16- and 2.34-fold higher than that by the original strain. Compared with mutant overexpressing ATF2 with BAT2 deletion, mutant overexpressing ATF1 with BAT2 deletion exhibited 48.17% decreased higher alcohol productivity. The production of higher alcohols in mutant overexpressing ATF2 with BAT2 deletion was similar to that in the BAT2 deletion mutant. Furthermore, no significant difference was observed between the BAT2 deletion mutant and the mutant overexpressing Lg-ATF1 with BAT2 deletion in terms of acetate ester and higher alcohol production. The mutants that have varying capacities for acetate ester and higher alcohol production can be potentially developed and applied. [ABSTRACT FROM AUTHOR]

Acetate esters and higher alcohols greatly influence the quality and flavor profiles of Chinese Baijiu (Chinese liquor). Various mutants have been constructed to investigate the interactions of ATF1 overexpression, IAH1 deletion, and BAT2 deletion on the production of acetate esters and higher alcohols. The results showed that the overexpression of ATF1 under the control of the PGK1 promoter with BAT2 and IAH1 double-gene deletion led to a higher production of acetate esters and a lower production of higher alcohols than the overexpression of ATF1 with IAH1 deletion or overexpression of ATF1 with BAT2 deletion. Moreover, deletion of IAH1 in ATF1 overexpression strains effectively increased the production of isobutyl acetate and isoamyl acetate by reducing the hydrolysis of acetate esters. The decline in the production of higher alcohol by the ATF1 overexpression strains with BAT2 deletion is due to the interaction of ATF1 overexpression and BAT2 deletion. Mutants with varying abilities of producing acetate esters and higher alcohols were developed by genetic engineering. These strains have great potential for industrial application. [ABSTRACT FROM AUTHOR]

Esters and higher alcohols produced by yeast during the fermentation of wort have the greatest impact on the smell and taste of beer. Alcohol acetyltransferase, which is mainly encoded by the ATF1 gene, is one of the most important enzymes for acetate ester synthesis. Cytosolic branched-chain amino acid aminotransferase, on the other hand, which is encoded by the BAT2 gene, plays an important role in the production of branched-chain alcohols. The objective of this study is to construct engineered brewer's yeast strains that produce more acetate esters and less higher alcohols. Industrial brewer's yeast strain S5 was used as the parental strain to construct ATF1 overexpression and BAT2 deletion mutants. The engineered strains S5-2 and S5-4, which feature partial BAT2 allelic genes replaced by the constructed ATF1 overexpression cassette, were obtained. The ester production of the engineered strains was observed to increase significantly compared with that of the parental cells. The concentrations of ethyl acetate produced by the engineered strains S5-2 and S5-4 increased to 78.88 and 117.40 mg L, respectively, or about 7.7-fold and 11.5-fold higher than that produced by parental S5 cells. The isoamyl acetate produced by S5-2 and S5-4 also increased to 5.14 and 9.25 mg L, respectively; by contrast, no isoamyl acetate was detected in the fermentation sample of the parental strain S5. Moreover, S5-2 and S5-4, respectively, produced about 65 and 51 % of higher alcohols produced by the parental strain. The increase in acetate ester content and decrease in higher alcohol concentration shown by the engineered brewer's yeast strains at the end of fermentation process indicate that the new strains are useful in future developments in the wheat beer industry. [ABSTRACT FROM AUTHOR]

Alcohol acetyltransferase ( AATase), which is mainly encoded by ATF 1, is one of the most important enzymes for acetate ester synthesis. On the other hand, isoamyl acetate is degraded into a higher alcohol under the catalysis of IAH 1-encoded esterase. In this study, Chinese Saccharomyces cerevisiae was used as the parent strain to construct an ATF 1 overexpression and IAH1 disruption mutant. The results show that after 5 days of pre-fermentation, the concentrations of ethyl acetate, isoamyl acetate and isobutyl acetate in the yellow rice wines fermented with EY1 ( pUC-PIAK) increased to 468.94 mg L−1 (which is approximately 22-fold higher than that of the parent cell RY1), 99.86 and 7.69 mg L−1 respectively. Meanwhile, isoamyl alcohol production was reduced to 56.37 mg L−1 (which is approximately 50% of that produced by the parent strain RY1). Therefore, ATF1 overexpression and IAH1 disruption can significantly increase acetate esters contents and reduce isoamyl alcohol content in Chinese yellow rice wine, thereby paving the way for breeding an excellent yeast strain for high-quality Chinese yellow rice wine production. [ABSTRACT FROM AUTHOR]

Flavour is an important key factor of apple ( Malus × domestica Borkh.) fruit quality, and its improvement is an important but complex breeding goal. Acetate esters are quantitatively the most important volatile compounds in apple fruit, and only a few of them dominate the typical aroma of a cultivar. Alcohol acyl-transferase (AAT) is a key enzyme involved in the last step of ester biosynthesis. The aim of this study was to target single nucleotide polymorphisms (SNPs) in an AAT candidate gene genetically associated with ester quantitative trait loci (QTL), to enable functional marker development for marker-assisted apple breeding programs. The AAT gene inventory of apple was characterized by in-silico mining of the assembled Golden Delicious genome, and 17 putative AAT genes in total were defined. MdAAT1 located on chromosome 2 was selected as the main candidate gene associated with QTL for different acetate esters, and its allelic diversity was assessed by direct amplicon sequencing in a collection of 102 apple cultivars characterized for ester volatile profiles. Sequencing a 468 bp nucleotide sequence of the MdAAT1 coding region resulted in the detection of four SNPs. In total, 18 different SNP haplotypes/heterozygous patterns were generated from the four SNPs identified within the apple collection. Association analyses resulted in highly significant associations of both individual SNPs and distinct haplotypes with the content of four acetate esters, including hexyl acetate, butyl acetate and 2-methyl-butyl acetate. About a third (31) of the 102 apple cultivars possessed the specific MdAAT1 haplotype H1 (C-A-C-A) and were characterized by strongly decreased ester concentrations. The contrasting H8 haplotype (T-G-T-G) was found in 28 varieties but was associated with normal to elevated ester concentrations. The observed association suggests a putative causal functional relationship between MdAAT1 and production of key apple esters. [ABSTRACT FROM AUTHOR]

Partition coefficients of hydrophilic organic solvents (C1-C5 acetate esters and alcohols) in distilled water, olive oil, human blood, and various rat tissues (blood, liver, kidney, brain, muscle, and fat) were determined. Water/air partition coefficients were measured by a new vial equilibration technique, which needs no direct measurement of the concentration in either the liquid phase or the gas phase, but only the gas chromatographic peak areas from both phases. Once the water/air partition coefficients had been measured, the blood/air, oil/air, and tissue/air partition coefficients could be measured by the previously developed vial equilibration method, which uses gas chromatographic peak areas from the gas phases in the sample (which contains test material) and the reference (which contains no test material) vessels. The alcohols tested were 32 (methanol) to 128 (n-pentanol) times more hydrophilic than the corresponding esters compared with oil/water partition coefficients. In general, water/air partition coefficients decreased and oil/air partition coefficients increased in proportion to the number of carbon atoms. Blood/air coefficients of alcohols were almost parallel to water/air partition coefficients, whereas no such relation was found with acetate esters. n-Isomers of both acetate esters and alcohols were found to be more soluble in water, blood, oil, and tissues than the corresponding iso-isomers. [ABSTRACT FROM AUTHOR]

Background: Enhancing the industrial yeast strains ethyl acetate yield through a precise and seamless genetic manipulation strategy without any extraneous DNA sequences is an essential requisite and significant demand., Objectives: For increasing the ethyl acetate yield of industrial brewer's yeast strain, all the ATF1 alleles were overexpressed through "self-cloning" integration strategy., Material and Methods: Escherichia coli strain DH5α was utilized for plasmid construction. ATF1 alleles were overexpressed through a precise and seamless insertion of the PGK1 promoter in industrial brewer's yeast strain S6. In addition, growth rates, ATF1 mRNA levels, AATase activity, the fermentation performance of the engineered strains, and gas chromatography (GC) analysis was conducted., Results: The two engineered strains (S6-P-12 and S6-P-30) overexpressed all ATF1 alleles but unaffected normal growth. The ATF1 mRNA levels of the S6-P-12 and S6-P-30 were all 4-fold higher than that of S6. The AATase (Alcohol acetyl transferases, encoded by ATF1 gene) activity of the two engineered strains was all 3-fold higher than that of the parent strain. In the beer fermentation at 10 ℃, the concentrations of ethyl acetate produced by the engineered strains S6-P-12 and S6-P-30 was increased to 23.98 and 24.00 mg L -1 , respectively, about 20.44% and 20.54% higher than that of S6., Conclusions: These results verify that the ethyl acetate yield could be enhanced by the overexpressed of ATF1 in the polyploid industrial brewer's yeast strains via "self-cloning" integration strategy. The present study provides a reference for target gene modification in the diploid or polyploid industrial yeast strains.

Ethylene glycol monomethyl ether (EGME) and its acetate ester (EGMEA) are highly flammable, colorless, moderately volatile liquids with very good solubility properties. They are used in paints, lacquers, stains, inks and surface coatings, silk-screen printing, photographic and photo lithographic processes, for example, in the semiconductor industry, textile and leather finishing, production of food-contact plastics, and as an anti-icing additive in hydraulic fluids and jet fuel. EGME and EGMEA are efficiently absorbed by inhalation as well as via dermal penetration. Dermal absorption may contribute substantially to the total uptake following skin contact with liquids or vapors containing EGME or EGMEA. EGMEA is rapidly converted to EGME in the bodyand the two substances are equally toxic in animals. Therefore, the two substances should be considered as equally hazardous to man. Effects on peripheral blood, testes, and sperm have been reported at occupational exposure levels ranging between 0.4 and 10 ppm EGME in air, and with additional, possibly substantial, dermal exposure. Severe malformations and disturbed hematopoiesis have been linked with exposure to EGME and EGMEA at unknown, probably high, levels. Embryonic deaths in monkeys and impaired spermatogenesis in rabbits have been reported after daily oral doses of 12 and 25 mg ,per kg body weight, respectively. In several studies, increased frequency of spontaneous abortions, disturbed menstrual cycle, and subfertility have been demonstrated in women working in the semiconductor industry. The contribution of EGME in relation to other exposure factors in the semiconductor industry is unclear. [ABSTRACT FROM AUTHOR]