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In order to develop tobacco flavors with good aroma release stability, a phase transfer catalytic method was used to synthesize carvacrol-β-D-glucoside. The pyrolysis of the synthesized carvacrol-β-D-glucoside was analyzed. It was also added to cigarettes to investigate its pyrolysis release behavior in the particulate phase of mainstream cigarette smoke and its application effect on flavoring. The results showed that: 1) Carvacrol-β-D-glucoside could be obtained by the phase transfer catalytic method, and its structure was confirmed by ¹H NMR, 13C NMR, FTIR, and HRMS. 2) At different heating temperatures, the main cleavage product of carvacrol-β-D-glucoside was carvacrol. 3) By adding carvacrol-β-D-glucoside to cigarettes in different flavoring ways, different flavoring effects could be achieved. The aroma release of cigarettes with carvacrol-β-D-glucoside in cut tobacco was more uniform and stable, and the flavoring effect was better than that of cigarettes with adding carvacrol directly. 4) Cigarettes with added carvacrol-β-D-glucoside could release carvacrol to the particulate phase of mainstream smoke during smoking, and the release of carvacrol increased with the increase of flavoring amount, while the transfer rate of carvacrol to the particulate phase of mainstream smoke was relatively stable. [ABSTRACT FROM AUTHOR]

To study the genes regulating the synthesis of sugar esters in tobacco, transcriptome sequencing analysis was performed on tobacco glandular hair cells and bundle sheath cells, and RT-qPCR was used for verification. The results showed that 11 962 differentially expressed genes were obtained, of which 5145 were up-regulated and 6817 were down-regulated. GO annotation of differentially expressed genes showed that the up-regulated genes mainly included biological processes (2265), molecular functions (1169), and cellular components (363), with a total of 3793 GO terms. Based on the assignment of KEGG pathway, the sequence was mapped to 122 metabolic pathways. Glycolysis/gluconeogenesis, starch and sucrose metabolism, phenylpropanoid biosynthesis related to glycoester synthesis were highly enriched, and acyl sugar pathway in glandular hairs was significantly up-regulated. By comparing with the tobacco reference genome, 12 up-regulated acyltransferase genes were identified in glandular hair cells. RT-qPCR results showed that the expression of 11 genes was higher than that of the control. The expression of gene 63826, gene 16194 and gene 37511 increased by 195.79 times, 166.23 times and 132.65 times, respectively. The above 11 genes may be involved in regulating the synthesis of sugar esters in glandular hair cells, providing a basis for further verification of gene function. [ABSTRACT FROM AUTHOR]

The extraction conditions of headspace solid phase microextraction (HS-SPME) of volatile flavor compounds from gluten-free potato steamed bread were optimized by response surface methodology based on the selection of extraction fibers. Meanwhile, composition of volatile components during the gluten free steamed bread processing was analyzed by HS-SPME and gas chromatography-mass spectrometry (GC-MS). Results showed that the extraction fiber of DVB/CAR/PDMS was suitable for the extraction of volatile flavor compounds from gluten-free potato steamed bread. The optimal SPME parameters were sample weight 2.42 g, extraction time 60 min, and extraction temperature 50 °C, the peak number and peak area/weight under the optimal conditions were 38 and 7. 75 x 107, respectively. In the process of making gluten-free potato steamed bread, a total of 69 volatile flavor compounds were detected, and the number increased significantly with the fermentation time increasing, especially the content of alcohols, acids and esters. Moreover, pyrazines content increased significantly during steaming process. [ABSTRACT FROM AUTHOR]

With chickpea as material, two Bacillus subtilisnatto strains (F-2-4 and S-15) isolated from different sources were selected and were inoculated into chickpea to prepare chickpea natto products by single-inoculation and co-inoculation, then nattokinase activity of chickpea natto was determined. Results showed that nattokinase activity was improved significantly by co-inoculation. When the inoculative volume ratio of F-2-4 and S-15 was 1:1, and inoculation amount was 4%, the nattokinase activity of chickpea natto reached the maximum 6 287.16 UI/g. [ABSTRACT FROM AUTHOR]