Impacts of preparation conditions on the structure and emulsifying properties of casein-alginate conjugates produced by transacylation reaction

A few years ago results on cryoprotection of L-valine were reported, where the values of the critical fluence De i.e, the electron exposure which decreases the intensity of the diffraction reflections by a factor e, amounted to the order of 2000 + 1000 e/nm2. In the meantime a discrepancy arose, since several groups published De values between 100 e/nm2 and 1200 e/nm2 /1 - 4/. This disagreement and particularly the wide spread of the results induced us to investigate more thoroughly the behaviour of organic crystals at very low temperatures during electron irradiation.For this purpose large L-valine crystals with homogenuous thickness were deposited on holey carbon films, thin carbon films or Au-coated holey carbon films. These specimens were cooled down to nearly liquid helium temperature in an electron microscope with a superconducting lens system and irradiated with 200 keU-electrons. The progress of radiation damage under different preparation conditions has been observed with series of electron diffraction patterns and direct images of extinction contours.

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The 3-Dimensional Molecular Structure of the Actin Filament Revisited

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100119223 ◽

1985 ◽

Vol 43 ◽

pp. 480-481

Author(s):

U. Aebi ◽

R. Millonig ◽

H. Salvo

Keyword(s):

Actin Filament ◽

Supramolecular Assembly ◽

Specimen Preparation ◽

X Ray Diffraction ◽

Single Filament ◽

X Ray ◽

3 Dimensional ◽

Filament Diameter ◽

Preparation Conditions ◽

Apparent Diameter

To date, most 3-D reconstructions of undecorated actin filaments have been obtained from actin filament paracrystal data (for refs, see 1,2). However, due to the fact that (a) the paracrystals may be several filament layers thick, and (b) adjacent filaments may sustantially interdigitate, these reconstructions may be subject to significant artifacts. None of these reconstructions has permitted unambiguous tracing or orientation of the actin subunits within the filament. Furthermore, measured values for the maximal filament diameter both determined by EM and by X-ray diffraction analysis, vary between 6 and 10 nm. Obviously, the apparent diameter of the actin filament revealed in the EM will critically depend on specimen preparation, since it is a rather flexible supramolecular assembly which can easily be bent or distorted. To resolve some of these ambiguities, we have explored specimen preparation conditions which may preserve single filaments sufficiently straight and helically ordered to be suitable for single filament 3-D reconstructions, possibly revealing molecular detail.

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Short-range order effects in amorphous FexSi1-x/Si multilayers induced by preparation conditions

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:1998242 ◽

1998 ◽

Vol 08 (PR2) ◽

pp. Pr2-175-Pr2-178 ◽

Cited By ~ 1

Author(s):

G. T. Pérez ◽

F. H. Salas ◽

R. Morales ◽

L. M. Álvarez-Prado ◽

J. M. Alameda

Keyword(s):

Short Range ◽

Short Range Order ◽

Range Order ◽

Order Effects ◽

Preparation Conditions

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Functional and Antioxidant Properties of Angelwing Clam (Phplas orientalis) Hydrolysate Produced using Alcalase

Scientific Research Journal ◽

10.24191/srj.v11i1.9399 ◽

2014 ◽

Vol 11 (1) ◽

pp. 29

Author(s):

Nonnah Ismail ◽

Juliana Mahmod ◽

Awatif Khairul Fatihin Mustafa Kamal

Keyword(s):

Antioxidant Properties ◽

Enzyme Concentration ◽

Degree Of Hydrolysis ◽

Emulsifying Properties ◽

Hydrolysis Time ◽

Chelating Activity ◽

Metal Chelating ◽

Metal Chelating Activity ◽

Intermediate Concentration ◽

As Solubility

In this study, Hydrolysate from angelwing clam (Pholas orientalis) was produced at 0, 1, 2 and 3 hrs and E/S ratio of0.5 and 3%using alcalase where the pH and temperature were kept constant at pH 8.5 and 60°C, respectively. The hydrolysates were analysed for antioxidant and functional properties such as solubility, emulsifying properties and water and oil holding capacity. Degree of hydrolysis (DH), yield, functional and antioxidant properties were influenced by the hydrolysis time and E/S ratio. Higher enzyme concentration (E/S 3%) and longer hydrolysis time increased the DH. Yield was higher at E/S 3% but reduced with hydrolysis time. Longer hydrolysis time produced more soluble hydrolysate and higher metal chelating activity but lower in emulsifying properties and DPPH activity. Higher enzyme concentration resulted in increase only in solubility and metal chelating activity. This study revealed that enzymatic hydrolysis using alcalase should be performed at shorter hydrolysis time using intermediate concentration of enzyme (E/S between 0.5 to 3%) in order to produce angelwing clam hydrolysate with collectively good functional and antioxidant properties.

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