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Silica fiber with highly ordered mesoporous structure and continuously long fibrous property was synthesized on a large-scale for the first time. It can be applied to the rapid (less than 3 min) and effective enrichment of endogenous peptides with a novel lab-in-syringe approach.

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.

Ethyl acetate has attracted much attention as an important chemical raw material and a flavor component of alcoholic beverages. In this study, the biosynthetic pathway for the production of ethyl acetate in Chinese liquor yeast was unblocked. In addition to engineering Saccharomyces cerevisiae to increased intracellular CoA and acetyl-CoA levels, we also increased the combining efficiency of acetyl-CoA to ethanol. The genes encoding phosphopantothenate-cysteine ligase, acetyl-CoA synthetase, and alcohol acetyltransferase were overexpressed by inserting the strong promoter PGK1p and the terminator PGK1t, respectively, and then combine them. Our results finally showed that the ethyl acetate levels of all engineering strains were improved. The final engineering strain CLy12a-ATF1-ACS2-CAB2 had a significant increase in ethyl acetate yield, reaching 610.26 (± 14.28) mg/L, and the yield of higher alcohols was significantly decreased. It is proved that the modification of ethyl acetate metabolic pathway is extremely important for the production of ethyl acetate from Saccharomyces cerevisiae.

The effect of light and water on aromatic rice remain largely unclear. A pot experiment was conducted to investigate the influences of light-water treatments (CK: natural light and well-watered conditions, WS: natural light and water-stressed conditions, LL: low light and well-watered conditions, LL-WS: low light and water-stressed treatment) on yield and 2-acetyl-1-pyrroline (2AP) formation in aromatic rice. Compared with CK, the light-water treatments decreased grain yield (10.32–39.19%) due to reductions in the filled grain percentage and total dry weight, in the regulation of biomass distribution, and in the attributes of gas exchange and antioxidant response parameters. The 2AP content in grains increased in the LL treatment (5.08–16.32%) but decreased in the WS treatment compared with that in CK. The changes in 2AP were associated with changes in 2AP formation-related traits and element content. Low light and water stress led to yield declines in aromatic rice, but low light alleviated the decrease in 2AP content caused by water stress.

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Tangzhiqing formula, a Chinese herbal formula, is used for the treatment of type II diabetes and prediabetes. Although its effectiveness has been certified by clinical use, its absorbed chemical constituents are not comprehensively represented. Thence, in order to reveal potential bioactive components and metabolism of Tangzhiqing formula, an ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry method was developed. A total of 86 absorbed components, including 38 prototype compounds and 48 metabolites, were identified in rat plasma, urine, and feces after oral administration of Tangzhiqing formula. This was the first systematic study on the chemical constituents and metabolic profiling of Tangzhiqing formula. The results indicated that alkaloids and flavonoids were main absorbed components, and glucuronidation and sulfation were the major metabolites. Moreover we concluded that alkaloids and flavonoids first underwent demethylation and hydrolysis reactions before biotransformed to phase II metabolites. This study provided valuable data for safety estimation of Tangzhiqing formula, which will be advantageous for clinical application.

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