Evaluation of four Candida utilis strains for biomass, acetic acid and ethyl acetate production from ethanol

Abstract Ethyl-acetate is important for the flavor and aroma of the alcoholic beverages, therefore, there have been extensive efforts toward increasing its production by engineering yeast strains. In this study, we reported a new approach to breed non-genetic modified producing yeast strain with higher ethyl-acetate production for beer brewing. First, we demonstrated the positive effect of higher acetic acid concentration on inducing the expression of ACS. Then, we applied adaptive laboratory evolution method to evolve strain with higher expression level of ACS. As a result, we obtained several strains with increased ACS expression level as well as ethyl-acetate production. In 3 L scale fermentation, the optimal strain EA60 synthesized more ethyl-acetate than M14 at the same time point. At the end of fermentation, the ethyl-acetate production in EA60 was 21.4% higher than M14, while the other flavor components except for acetic acid were changed in a moderate degree, indicating this strain had a bright prospect in industrial application. Moreover, this study also indicated that ACS1 played a more important role in increasing the acetic acid tolerance of yeast, while ACS2 contributed to the synthesis of cytosol acetyl-CoA, thereby facilitating the production of ethyl-acetate during fermentation.

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Screening lager yeast with higher ethyl-acetate production by adaptive laboratory evolution in high concentration of acetic acid

World Journal of Microbiology and Biotechnology ◽

10.1007/s11274-021-03082-7 ◽

2021 ◽

Vol 37 (7) ◽

Author(s):

Xin Xu ◽

Chengtuo Niu ◽

Chunfeng Liu ◽

Jinjing Wang ◽

Feiyun Zheng ◽

...

Keyword(s):

Acetic Acid ◽

Ethyl Acetate ◽

High Concentration ◽

Acetate Production ◽

Adaptive Laboratory Evolution ◽

Lager Yeast ◽

Laboratory Evolution

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Interlaboratory comparison of results of erythrocyte protoporphyrin analysis.

Clinical Chemistry ◽

10.1093/clinchem/24.12.2135 ◽

1978 ◽

Vol 24 (12) ◽

pp. 2135-2138 ◽

Cited By ~ 5

Author(s):

K W Jackson

Keyword(s):

Acetic Acid ◽

Hydrochloric Acid ◽

Ethyl Acetate ◽

Disease Control ◽

Whole Blood ◽

Interlaboratory Comparison ◽

Direct Reading ◽

Blood Samples ◽

Erythrocyte Protoporphyrin ◽

Whole Blood Samples

Abstract Each of 65 laboratories analyzed 10 whole-blood samples for erythrocyte protoporphyrin by one or more of several analytical procedures. These procedures were of two types: (a) extraction of protoporphyrin from the erythrocytes into ethyl acetate/acetic acid, re-extraction into hydrochloric acid, and fluorometric measurement; or (b) direct reading in a portable fluorometer (hematofluorometer), with no pretreatment of the blood sample. Interlaboratory correlation was generally poor, especially between laboratories using extraction procedures. Hematofluorometric results intercorrelated better, but they had a low bias as compared to the extraction approach. Nationwide standardization of the test is required to assure satisfactory interlaboratory performance and to identify laboratories whose results are sufficiently accurate to be used for interpretations according to guidelines set forth by the Center for Disease Control for erythrocyte protoporphyrin testing.

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HSCCC Separation of Three Main Compounds from the Crude Extract of Dracocephalum Tanguticum by Using Dimethyl Sulfoxide as Cosolvent

Journal of Chromatographic Science ◽

10.1093/chromsci/bmaa094 ◽

2020 ◽

Author(s):

Xue Yang ◽

Yongling Liu ◽

Tao Chen ◽

Nana Wang ◽

Hongmei Li ◽

...

Keyword(s):

Acetic Acid ◽

Ethyl Acetate ◽

Dimethyl Sulfoxide ◽

Efficient Method ◽

Crude Extract ◽

High Speed ◽

Glacial Acetic Acid ◽

Butyl Alcohol ◽

Preparative Hplc ◽

Counter Current

Abstract Separation of natural compounds directly from the crude extract is a challenging work for traditional column chromatography. In the present study, an efficient method for separation of three main compounds from the crude extract of Dracocephalum tanguticum has been successfully established by high-speed counter-current chromatography (HSCCC). The crude extract was directly introduced into HSCCC by using dimethyl sulfoxide as cosolvent. Ethyl acetate/n-butyl alcohol/0.3% glacial acetic acid (4: 1: 5, v/v) system was used and three target compounds with purity higher than 80% were obtained. Preparative HPLC was used for further purification and three target compounds with purity higher than 98% were obtained. The compounds were identified as chlorogenic acid, pedaliin and pedaliin-6″-acetate.

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Improving Ethyl Acetate Production in Baijiu Manufacture by Wickerhamomyces anomalus and Saccharomyces cerevisiae Mixed Culture Fermentations

BioMed Research International ◽

10.1155/2019/1470543 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 4

Author(s):

Guangsen Fan ◽

Chao Teng ◽

Dai Xu ◽

Zhilei Fu ◽

Pengxiao Liu ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Ethyl Acetate ◽

Mixed Culture ◽

Nutrient Competition ◽

Acetate Production ◽

Mixed Fermentation ◽

Wickerhamomyces Anomalus ◽

Flavor Perception ◽

Positive Effect

Ethyl acetate content has strong influence on the style and quality of Baijiu. Therefore, this study investigated the effect of Saccharomyces cerevisiae Y3401 on the production of ethyl acetate by Wickerhamomyces anomalus Y3604. Analysis of cell growth showed that Y3401 influences Y3604 by nutrient competition and inhibition by metabolites, while the effect of Y3604 on Y3401 was mainly competition for nutrients. Mixed fermentation with two yeasts was found to produce more ethyl acetate than a single fermentation. The highest yield of ethyl acetate was 2.99 g/L when the inoculation ratio of Y3401:Y3604 was 1:2. Synergistic fermentation of both yeasts improved ethyl acetate production and increased the content of other flavor compounds in liquid and simulated solid-state fermentation for Baijiu. Saccharomyces cerevisiae had a positive effect on ethyl acetate production in mixed culture and provides opportunities to alter the aroma and flavor perception of Baijiu.

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