Densities, viscosities, refractive indices, and speeds of sound in methyl acetoacetate + methyl acetate + ethyl acetate, + n-butyl acetate, + methyl benzoate, and + ethyl benzoate at 298.15, 303.15, and 308.15 K

The effect of reconstituted milk inoculation with Streptococcus thermophilus TM11 and Streptococcus thermophilus SP 1.1 on soft cheese volatiles was investigated. The impact flavors of 2,3-butanedione, 2,3-pentanedione, ethyl acetate, methyl butyrate, ethyl butyrate, butyl acetate and butyric acid were only detected in the fermented cheeses. Levels of diketones were higher in the cheeses fermented by mixed cultures than single culture, while levels of esters except ethyl acetate and butyl acetate showed an opposite tendency. There was significant difference in the levels of 2-hexenal and 2-nonenal among the cheeses. Other compounds originated from lipid oxidation, Strecker degradation, biosynthesis and forages were not significantly influenced by milk inoculation with Streptococcus thermophilus.

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Study of Refractive Indices and Its Theories for Mixtures of N, N-Diethylethanamine and Acetates

Journal of Scientific Research ◽

10.3329/jsr.v12i3.43717 ◽

2020 ◽

Vol 12 (3) ◽

pp. 363-370

Author(s):

P. Tyagi ◽

K. Kumar ◽

M. Rani ◽

N. Sabharwal

Keyword(s):

Experimental Data ◽

Methyl Acetate ◽

Butyl Acetate ◽

Composition Range ◽

Polynomial Equation ◽

Carbon Chain ◽

Refractive Indices ◽

Carbon Chain Length ◽

Propyl Acetate ◽

Empirical Correlations

This paper reports the refractive indices ( ) of N,N-diethylethanamine + methyl acetate, ethyl acetate, propyl acetate, butyl acetate and pentyl acetate at 298.15 K and at different composition range. The various empirical correlations like Arago-Biot (AB), Gladstone-Dale (GD), Lorentz-Lorenz (L-L) Heller (H), Weiner (W), Newton (Nw) and Erying-John (E-J) were applied to experimental data for estimating theoretical value of refractive indices. For an equimolar mixture, the predicted deviation in refractive index values is consistent well with the experimental data. It has been found that the interactions between amine and different esters decrease when carbon chain length in ester increases. Also refractive indices are affected with change in temperature. To evaluate the standard deviation, RK polynomial equation was fitted to the measured refractive indices data.

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Insulinotropic action of α-d-glucose pentaacetate: functional aspects

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1997.273.6.e1090 ◽

1997 ◽

Vol 273 (6) ◽

pp. E1090-E1101

Author(s):

Willy J. Malaisse ◽

Carmen Sánchez-Soto ◽

M. Elena Larrieta ◽

Marcia Hiriart ◽

Hassan Jijakli ◽

...

Keyword(s):

Ethyl Acetate ◽

Insulin Release ◽

Methyl Acetate ◽

Cytochalasin B ◽

Secretory Response ◽

Coupling Mechanism ◽

Functional Aspects ◽

Acetate Methyl ◽

Glucose Pentaacetate ◽

Stimulate Insulin Release

The functional determinants of the insulinotropic action of α-d-glucose pentaacetate were investigated in rat pancreatic islets. The ester mimicked the effect of nutrient secretagogues by recruiting individual B cells into an active secretory state, stimulating proinsulin biosynthesis, inhibiting86Rb outflow, and augmenting45Ca efflux from prelabeled islets. The secretory response to the ester was suppressed in the absence of Ca2+ and potentiated by theophylline or cytochalasin B. The generation of acetate from the ester apparently played a small role in its insulinotropic action. Thus acetate, methyl acetate, ethyl acetate, α-d-galactose pentaacetate, and β-d-galactose pentaacetate all failed to stimulate insulin release. The secretory response to α-d-glucose pentaacetate was reproduced by β-d-glucose pentaacetate and, to a lesser extent, by β-l-glucose pentaacetate. It differed from that evoked by unesterifiedd-glucose by its resistance to 3- O-methyl-d-glucose,d-mannoheptulose, and 2-deoxy-d-glucose. It is concluded that the insulinotropic action of α-d-glucose pentaacetate, although linked to the generation of the hexose from its ester, entails a coupling mechanism that is not identical to that currently implied in the process of glucose-induced insulin release.

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