TALANTA
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2024
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IF 5.6
Xiao Jia,Jingnan Ren,Zhifeng Zhang,Nawei Zhang,Qi An,Mingzhe Li,Siyi Pan,Gang Fan,Jinchu Yang,Yingjie Feng,Zongcan Yang,Yongming Xu
ABSTRACT The non-thermal and thermal effects on aroma of sea buckthorn juice have rarely been investigated. In this study, 57 odor compounds were identified in fresh sea buckthorn juice (FSBJ), high pressure processing sea buckthorn juice (HSBJ), and pasteurized sea buckthorn juice (PSBJ), including 29 esters, 8 aldehydes, 1 ketone, 5 alcohols, 5 acids, 6 terpenoids, and 3 others. Ethyl 2-methylbutanoate, ethyl 3-methylbutanoate, ethyl hexanoate, and ethyl 2-hydroxy-3-methylbutanoate with flavor dilution factors ranging from 729 to 59049 contributed to the fruity odors of FSBJ and HSBJ. Besides, the formation of off-odor compounds including hexanal, nonanal, furfural, 3-methylbutanoic acid, and dimethyl disulfide with odor activity values ≥ 1, imparts fatty, roasted, sweaty, and cooked odor in PSBJ. The variations of vitamin C and reducing sugar are significantly associated with changes in odor-active compounds during pasteurized processing. These findings provide new insights that high pressure processing minimizes the adverse effects of pasteurization.
研究领域:
食品科学
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农业化学
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食品加工
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2016
·
IF 4.758
Jun Lv,Chen Chen,Chao Qian,Wanyi Chen,Yang Xiang,Juan Zhang
A colorimetric sensing method has been proposed for the detection of β-lactamase (β-Lac) activity and the screening of the inhibitors in this work. The method is based on the aggregation of AuNPs induced by 2-amino-3-mercapto-3-methylbutanoic acid (AMMBA) through the formation of Au-S bond and electrostatic interaction . Since AMMBA can form through β-Lac catalyzed hydrolysis and Cu(II)-mediated redox with penicillin as enzyme substrate, β-Lac activity is related to the extent of AuNPs aggregation. The enzyme activity can be determined at levels as low as 0.556 U/mL and over a linear detection range as wide as from 0 U/mL to 30 U/mL. Furthermore, the inhibitory effects of clavulanic acid and sulbactam on the activity of β-Lac have also been tested and given IC 50 values of 0.92 μM and 0.06 μM, respectively. The proposed method can be not only used for the detection of β-Lac activity but also the screening of the inhibitor.
研究领域:
生物化学
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医学诊断
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分析化学
✓ 已验证
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2025
·
IF 6.2
Yihan Chen,Wanqing Wei,Jianhao Xu,Wei Song,Jian Wen,Guipeng Hu,Xiaomin Li,Cong Gao,Jing Wu
3-Hydroxy-3-methylbutyrate (HMB), an important dietary supplement, can enhance the quality of life for sedentary and elderly people. However, the catalytic efficiency of the pathway enzymes limited the biosynthesis of HMB. Here, we identified an efficient 4-hydroxyphenylpyruvate dioxygenase (4-HPPD) from Bacteroides barnesiae (BbHPPD) that converted l-Leucine (l-Leu) to HMB together with an efficient L-amino acid deaminase (L-AAD) in lab-preserved Proteus mirabilis (PmL-AADQ92A). The regioselective hydroxylation mechanism of the decarboxylated intermediate of 4-methyl-2-oxopentanoic acid (α-KIC) catalyzed by BbHPPD was elucidated for the first time. Structure-guided semirational design of BbHPPD generated a mutant M4. Compared to the wild type, the titer of mutant M4 increased by 254% when using α-KIC as a substrate. Finally, the engineered Escherichia coli 06 strain achieved the HMB titer of 11.6 g/L, a molar conversion of 65%, and a space-time yield of 0.64 g/(L·h) (the highest to date) in 18 h. This study lays the foundation for industrial-scale biosynthesis of HMB.
研究领域:
生物化学
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合成生物学
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代谢工程
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2018
·
IF 3.412
Jia Huang,Yuping Liu,Wenxi Yang,Yingqiao Liu,Yu Zhang,Mingquan Huang,Baoguo Sun
Beijing douzhi (BD) is a traditional snack in Beijing, China, and it has been listed as a part of Beijing’s intangible cultural heritage. The potent odorants that contribute to the characteristic aroma of BD were investigated by analyzing the isolates from solvent-assisted flavor evaporation (SAFE) and simultaneous distillation–extraction. Using aroma extract dilution analysis based on gas chromatography–mass spectrometry and gas chromatography-olfactometry, 31 aroma-active compounds with flavor dilution (FD) factors ranging from 1 to 2187 were identified by comparison of their odor characteristics, MS data, and retention indices with those of reference compounds. To further determine their contribution to the aroma of BD, the odorants isolated using SAFE with FD factors ≥9 were quantified, and their odor activity values (OAVs; ratio of concentration to the respective odor threshold in water) were calculated. Eleven compounds were found to have OAVs ≥ 1, which indicated they were the potent odorants that contributed substantially to the characteristic aroma of BD. Among the 11 odorants, (E,Z)-2,6-nonadienal, eugenol, methional, p-cresol, 1-octen-3-one, and 3-methylbutanoic acid were not previously identified in BD.
研究领域:
食品科学
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分析化学
·
香料化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2020
·
IF 4.972
Juan Wang,Changjiang Yuan,Xiulin Gao,Yongliang Kang,Mingquan Huang,Jihong Wu,Yuping Liu,Jinglin Zhang,Hehe Li,Yuyu Zhang
Huangjiu (yellow rice wine) from Shanxi province, with a dominant Zao-aroma (fermented grain aroma), is particularly popular in northern China. The key aroma compounds in Huangjiu from Shanxi province were characterized by sensory-directed flavor analysis. A total of 106 compounds separated with solvent-assisted flavor evaporation (SAFE) distillation were identified by gas chromatography-olfactometry (GC-O) coupled with aroma extract dilution analysis (AEDA) and odor specific magnitude estimation (Osme). Forty-seven of them were further quantitated and 21 odorants had odor activity values (OAVs) ≥ 1. The aroma profiles of three recombination models had >95.84% similarities to their corresponding samples. And then, the omission/addition tests further confirmed that β -phenylethanol, 3-methylbutanoic acid, ethyl lactate, sotolon, 2-acetyl-1-pyrroline, vanillin, ethyl cinnamate, ethyl 3-phenylpropionate, 3-methylbutanal, and methional were the key odorants for Huangjiu from Shanxi province. Meanwhile, it was firstly confirmed that ethyl cinnamate and ethyl 3-phenylpropionate played the key roles in the overall aroma of Huangjiu.
研究领域:
食品科学
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化学感官科学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2018
·
IF 3.52
Jia Zheng,Dong Zhao,Zhifu Peng,Kangzhuo Yang,Qiang Zhang,Yongkui Zhang
Changes of volatile compounds and sensory properties in the fermentation process of Wuliangye baobaoqu starter (WBS) were determined by sensory analysis, gas chromatography-olfactometry (GC/O) and GC quantitative analyses. The sensory properties of WBS changed from the sour, fruity, bready notes at the temperature-rise phase (3-day and 7-day) to the nutty and moldy notes at the temperature-fall phase (18-day, 21-day and 27-day). Acetic acid, methional, ethyl acetate, phenylethyl alcohol, ethyl 2-phenylacetate, 4-vinylguaiacol were potential aroma active compounds based on their Osme values. Results of GC quantitative analyses showed that the acids had the highest concentration. The concentration of ( E )-2-hexenal, ethyl acetate, isoamyl alcohol, phenylethyl alcohol, 2- n -pentylfuran, acetic acid and lactic acid increased with the fermentation time, presented the highest level in the temperature-rise phase and decreased after this period. The concentration of ( E,E )-2,4-hexadienal, 2,6-dimethylpyrazine, trimethylpyrazine, tetramethylpyrazine presented the highest level at the temperature-fall phase. Ethyl 3-methylbutanoate, ( E , E )-2,4-hexadienal, ( E , E )-2,4-nonadienal, acetic acid and butanoic acid had high odor active values. Results of principal component analysis showed that acetic acid, hexanal, ( E )-2-hexenal, lactic acid, isoamyl alcohol, 1-hexanol and 1-octen-3-ol were critical volatile chemicals to distinguish different WBS samples.
研究领域:
食品科学
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分析化学
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感官科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子