The recovery of caproic acid from the aqueous stream is of practical relevance due to its market value and the stringent environmental standards. The profound success of reactive extraction has been noted in the recov...The recovery of caproic acid from the aqueous stream is of practical relevance due to its market value and the stringent environmental standards. The profound success of reactive extraction has been noted in the recovery of carboxylic acids from dilute solutions. In present paper, equilibrium of caproic acid with aliquat-336, a quaternary amine compound, in xylene and Methyl Isobutyl Ketone (MIBK) has been studied. Equilibrium parameters such as distribution coefficients, loading ratio, degree of extraction and equilibrium complexation constants have been presented. The data obtained is useful in understanding the equilibrium characteristics and efficient design of the recovery process of caproic acid by reactive extraction.展开更多
Caproic acid is a significant flavor compound of strong-flavor Baijiu,which is primarily produced by microorganisms inhabiting pit mud.The adaptive evolution mechanisms during the long-term brewing process for decades...Caproic acid is a significant flavor compound of strong-flavor Baijiu,which is primarily produced by microorganisms inhabiting pit mud.The adaptive evolution mechanisms during the long-term brewing process for decades even centuries of three caproic acid-producing bacterial genera,Caproicibacter,Caproicibacterium,and Caproiciproducens(CAP),which were challenging to cultivate from the pit mud,were examined in this study utilizing metagenomics and comparative genomics.The results indicated that CAPs progressively acclimated to the pit mud environment and took over as the dominant microorganisms in the community with continuous brewing.CAPs in the aged pit mud contained more genes linked to the synthesis of short-chain fatty acids,a greater capacity to metabolize small molecules,and a decreased capacity to metabolize starch macromolecules.More ethanol and lactic acid metabolism-related gene types were evolved by CAPs in the aged pit mud,and their capacity to metabolize these substances was greater.In order to assist them adjust to the high alcohol and high acid environment,CAPs in the aged pit mud possessed additional defense mechanisms and genes linked to environmental adaptability.The adaptive evolutionary mechanism of caproic acid-producing bacteria during long-term fermentation was examined in this study.This analysis served as a foundation for additional regulation of the metabolic activity of these bacteria and offered theoretical support for preserving and enhancing pit mud quality.展开更多
浓香型白酒的主体香味物质是己酸乙酯,己酸菌是重要的功能菌种。该研究从优质窖泥中分离获得了高产己酸菌株,命名为JZZ,该菌是革兰氏阳性杆菌,经形态学和16S r DNA序列鉴定,属于克氏梭菌(Clostridium kluyveri)。通过培养条件考察,该己...浓香型白酒的主体香味物质是己酸乙酯,己酸菌是重要的功能菌种。该研究从优质窖泥中分离获得了高产己酸菌株,命名为JZZ,该菌是革兰氏阳性杆菌,经形态学和16S r DNA序列鉴定,属于克氏梭菌(Clostridium kluyveri)。通过培养条件考察,该己酸菌最适培养条件为接种量5%,装样量90%,培养温度37℃,p H值为6.5。在最适培养条件下,菌株JZZ的己酸产量均可达到4.36 mg/m L。展开更多
文摘The recovery of caproic acid from the aqueous stream is of practical relevance due to its market value and the stringent environmental standards. The profound success of reactive extraction has been noted in the recovery of carboxylic acids from dilute solutions. In present paper, equilibrium of caproic acid with aliquat-336, a quaternary amine compound, in xylene and Methyl Isobutyl Ketone (MIBK) has been studied. Equilibrium parameters such as distribution coefficients, loading ratio, degree of extraction and equilibrium complexation constants have been presented. The data obtained is useful in understanding the equilibrium characteristics and efficient design of the recovery process of caproic acid by reactive extraction.
基金supported by the National Natural Science Foundation of China[grant number 32370142]Sichuan Science and Technology Program[grant number 2025ZNSFSC0199]China Postdoctoral Science Foundation[grant numbers 2024T170375 and 2023M741512].
文摘Caproic acid is a significant flavor compound of strong-flavor Baijiu,which is primarily produced by microorganisms inhabiting pit mud.The adaptive evolution mechanisms during the long-term brewing process for decades even centuries of three caproic acid-producing bacterial genera,Caproicibacter,Caproicibacterium,and Caproiciproducens(CAP),which were challenging to cultivate from the pit mud,were examined in this study utilizing metagenomics and comparative genomics.The results indicated that CAPs progressively acclimated to the pit mud environment and took over as the dominant microorganisms in the community with continuous brewing.CAPs in the aged pit mud contained more genes linked to the synthesis of short-chain fatty acids,a greater capacity to metabolize small molecules,and a decreased capacity to metabolize starch macromolecules.More ethanol and lactic acid metabolism-related gene types were evolved by CAPs in the aged pit mud,and their capacity to metabolize these substances was greater.In order to assist them adjust to the high alcohol and high acid environment,CAPs in the aged pit mud possessed additional defense mechanisms and genes linked to environmental adaptability.The adaptive evolutionary mechanism of caproic acid-producing bacteria during long-term fermentation was examined in this study.This analysis served as a foundation for additional regulation of the metabolic activity of these bacteria and offered theoretical support for preserving and enhancing pit mud quality.
