Factor analysis is used to study the organic compounds that have high degree of correlation with biomass in algal blooming. Based on this correlation, they are named characteristic organic compounds. The compounds fou...Factor analysis is used to study the organic compounds that have high degree of correlation with biomass in algal blooming. Based on this correlation, they are named characteristic organic compounds. The compounds found are sequalene (SQU), cedrol (CED), 2, 5-cyclohexadiene-1, 4-dione, 2, 6-bis(1, 1-dimthylethyl ) (PBQ), phenol, 2, 6-bis (1, 1-dimethylethy-4-methyl) (BHT), 3-t-butyl-4- hydroxyanisole ( BHA ), 1, 2-benzenedicarboxylie acid, bis-( 2-methyl propyl ) ester (DIBP), dibutyl phthalate (DNBP), respectively. Monitoring the variations of concentration of these characteristic organic compounds in seawater may provide scientific basis for studying and forecasting red tides.展开更多
The stability of the coordination compounds of the first transition series metal ions(Mn(Ⅱ),Co(Ⅱ),Ni(Ⅱ),Cu(Ⅱ)and Zn(Ⅱ))with 2-mercaptopyridine-1- oxide is reported.A coordination compound CoL_2 is synthesized and...The stability of the coordination compounds of the first transition series metal ions(Mn(Ⅱ),Co(Ⅱ),Ni(Ⅱ),Cu(Ⅱ)and Zn(Ⅱ))with 2-mercaptopyridine-1- oxide is reported.A coordination compound CoL_2 is synthesized and characterized for the first time.展开更多
Based on our structural model and a tight-binding Hamiltonian the eIectronic structure has been calculated by use of a recursion method (RM) for two models of the tetragonal DO22 and the cubic Ll2 crystal structures i...Based on our structural model and a tight-binding Hamiltonian the eIectronic structure has been calculated by use of a recursion method (RM) for two models of the tetragonal DO22 and the cubic Ll2 crystal structures in Al3Ti+Cr for contrast, from which bonding characteristics have been discussed. The results for the interaction energy (IE) show that Cr prefers to replacing Al site. Cr partly replacing Al can change the IE between the atoms and make the constriction of lattice constant c and the elongation of lattice constant a for the DO22 and thereby may induce the change of crystal structure from DO22 to L12. The results for bond order integral (BOI) and IE between the atoms also show that the strong (110) directional Cr-Ti bondings are existed.Thus, Al3Ti-base intermetallic compounds with addition of the Cr atom still remain brittle.展开更多
Sweet orange has become increasingly popular worldwide due to its unique flavor and nutritional value.In this study,four characteristic aroma compounds of sweet orange(α-pinene,octanal,ethyl butyrate,linalool)were se...Sweet orange has become increasingly popular worldwide due to its unique flavor and nutritional value.In this study,four characteristic aroma compounds of sweet orange(α-pinene,octanal,ethyl butyrate,linalool)were selected,and their interactions were evaluated at the macroscopic level through sensory experiments with pairwise combinations.Subsequently,the S-curve method combined with molecular simulation technology was used to systematically analyze the differences in synergistic effects between three broad-spectrum olfactory receptors(OR1A1,OR2W1,OR52D1)and the four characteristic aroma compounds of sweet orange.Sensory experiments showed that at least one masking effect existed in the pairwise combinations,and differences in aroma types led to different olfactory adaptation rates,with the synergistic effect betweenα-pinene and ethyl butyrate being particularly significant.Molecular docking revealed that hydrogen bonds in the active center of OR2W1(SER109/ASN155)and the multiple hydrogen bond network of OR1A1(THR239/SER/ARG122)were key binding modes,while OR52D1 had the weakest binding ability due to fewer and shorter hydrogen bonds.The rigid structure ofα-pinene caused steric hindrance,affecting the synergistic effect.Molecular dynamics further revealed that the high RMSD value of OR52D1 reflected its conformational flexibility,while OR2W1 enhanced binding stability through a“hydrophobic network”.This study confirms that olfactory perception is the result of hydrogen bonds,hydrophobic interactions,and dynamic equilibrium of molecular conformations,providing a theoretical basis for the synergistic mechanism of complex aroma systems.展开更多
To simultaneously improve the extraction yield and preserve the characteristic aroma of black pepper essential oil(EO),this study investigated the synergistic role of pre-freezing and pulverization,as well as the effe...To simultaneously improve the extraction yield and preserve the characteristic aroma of black pepper essential oil(EO),this study investigated the synergistic role of pre-freezing and pulverization,as well as the effects of enzymatic hydrolysis on extraction yield and volatile composition.Twenty-three terpenoid compounds were identified as the characteristic volatile aroma compounds of black pepper EO through GC-MS-O coupled with aroma extract dilution analysis(AEDA),among which 3-carene,caryophyllene oxide,and cyclofenchene showed notably high flavor dilution(FD)factors of 243,729,and 729,respectively.A highly practical protocol of using pre-freezing at20◦C for 6 h followed by universal pulverization for 18 s(F-P-18s)was proposed to enhance both the yield and quality of black pepper EO.This method increased the EO yield from 2.35 mL/100 g to 2.74 mL/100 g.Physically,pre-freezing enhanced the brittleness of the black peppercorns,promoting more efficient cell rupture and facilitating a thorough release of intracellular EO.Subsequent enzymatic hydrolysis of the F-P-18s sample using Viscozyme L(VL)and Alcalase 2.4 L(AL)further increased the EO yield by 8.0%(from 2.74 mL/100 g to 2.96 mL/100 g),resulting in the highest total volatile compounds of 253.40±1.12 mg/mL.展开更多
基金This work is supported by the National Natural Science Foundation of China (29977029).
文摘Factor analysis is used to study the organic compounds that have high degree of correlation with biomass in algal blooming. Based on this correlation, they are named characteristic organic compounds. The compounds found are sequalene (SQU), cedrol (CED), 2, 5-cyclohexadiene-1, 4-dione, 2, 6-bis(1, 1-dimthylethyl ) (PBQ), phenol, 2, 6-bis (1, 1-dimethylethy-4-methyl) (BHT), 3-t-butyl-4- hydroxyanisole ( BHA ), 1, 2-benzenedicarboxylie acid, bis-( 2-methyl propyl ) ester (DIBP), dibutyl phthalate (DNBP), respectively. Monitoring the variations of concentration of these characteristic organic compounds in seawater may provide scientific basis for studying and forecasting red tides.
文摘The stability of the coordination compounds of the first transition series metal ions(Mn(Ⅱ),Co(Ⅱ),Ni(Ⅱ),Cu(Ⅱ)and Zn(Ⅱ))with 2-mercaptopyridine-1- oxide is reported.A coordination compound CoL_2 is synthesized and characterized for the first time.
文摘Based on our structural model and a tight-binding Hamiltonian the eIectronic structure has been calculated by use of a recursion method (RM) for two models of the tetragonal DO22 and the cubic Ll2 crystal structures in Al3Ti+Cr for contrast, from which bonding characteristics have been discussed. The results for the interaction energy (IE) show that Cr prefers to replacing Al site. Cr partly replacing Al can change the IE between the atoms and make the constriction of lattice constant c and the elongation of lattice constant a for the DO22 and thereby may induce the change of crystal structure from DO22 to L12. The results for bond order integral (BOI) and IE between the atoms also show that the strong (110) directional Cr-Ti bondings are existed.Thus, Al3Ti-base intermetallic compounds with addition of the Cr atom still remain brittle.
基金funded by the Key Projects of the National Natural Science Foundation of China(32330080)Collaborative Innovation Fund of Shanghai Institute of Technology(XTCX 2023-15).
文摘Sweet orange has become increasingly popular worldwide due to its unique flavor and nutritional value.In this study,four characteristic aroma compounds of sweet orange(α-pinene,octanal,ethyl butyrate,linalool)were selected,and their interactions were evaluated at the macroscopic level through sensory experiments with pairwise combinations.Subsequently,the S-curve method combined with molecular simulation technology was used to systematically analyze the differences in synergistic effects between three broad-spectrum olfactory receptors(OR1A1,OR2W1,OR52D1)and the four characteristic aroma compounds of sweet orange.Sensory experiments showed that at least one masking effect existed in the pairwise combinations,and differences in aroma types led to different olfactory adaptation rates,with the synergistic effect betweenα-pinene and ethyl butyrate being particularly significant.Molecular docking revealed that hydrogen bonds in the active center of OR2W1(SER109/ASN155)and the multiple hydrogen bond network of OR1A1(THR239/SER/ARG122)were key binding modes,while OR52D1 had the weakest binding ability due to fewer and shorter hydrogen bonds.The rigid structure ofα-pinene caused steric hindrance,affecting the synergistic effect.Molecular dynamics further revealed that the high RMSD value of OR52D1 reflected its conformational flexibility,while OR2W1 enhanced binding stability through a“hydrophobic network”.This study confirms that olfactory perception is the result of hydrogen bonds,hydrophobic interactions,and dynamic equilibrium of molecular conformations,providing a theoretical basis for the synergistic mechanism of complex aroma systems.
基金funded by the National Key R&D Program of China(2023YFD2100500)“Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province”.
文摘To simultaneously improve the extraction yield and preserve the characteristic aroma of black pepper essential oil(EO),this study investigated the synergistic role of pre-freezing and pulverization,as well as the effects of enzymatic hydrolysis on extraction yield and volatile composition.Twenty-three terpenoid compounds were identified as the characteristic volatile aroma compounds of black pepper EO through GC-MS-O coupled with aroma extract dilution analysis(AEDA),among which 3-carene,caryophyllene oxide,and cyclofenchene showed notably high flavor dilution(FD)factors of 243,729,and 729,respectively.A highly practical protocol of using pre-freezing at20◦C for 6 h followed by universal pulverization for 18 s(F-P-18s)was proposed to enhance both the yield and quality of black pepper EO.This method increased the EO yield from 2.35 mL/100 g to 2.74 mL/100 g.Physically,pre-freezing enhanced the brittleness of the black peppercorns,promoting more efficient cell rupture and facilitating a thorough release of intracellular EO.Subsequent enzymatic hydrolysis of the F-P-18s sample using Viscozyme L(VL)and Alcalase 2.4 L(AL)further increased the EO yield by 8.0%(from 2.74 mL/100 g to 2.96 mL/100 g),resulting in the highest total volatile compounds of 253.40±1.12 mg/mL.
