Research of the mineral composition of freeze-dried plant powders

In this study, the blueberries (BLUB), raspberries (RASB), blackberries (BLCB), pomegranates pomace (POME) and beetroots (BEET) freeze-dried powders were used as the sources of phenolic compounds to enrich different types of chocolates, substituting a part of the sweetener. It was found that 1% addition of fruit or vegetable powders to chocolates increased the content of total phenolic compounds (flavan-3-ols, phenolic acids and anthocyanins) of enriched dark and milk chocolates compared to the control ones dependent on the powder used. Among the enriched chocolates, the chocolates with the addition of BLUB powder were characterized by the highest total polyphenol content. The highest percentage increase (approximately 80%) in the total polyphenol content was observed in MCH chocolate enriched with BLUB powder. Chocolates incorporated with BLUB, RASB, BLCB and POME powders presented a richer phenolic compound profile than control counterparts. The highest DPPH radical-scavenging capacity was exhibited by the DCH98S chocolate enriched with BEET powder. However, the DCH98ESt chocolates enriched with POME and BEET powders demonstrated the highest FRAP values. An electronic nose analysis confirmed the existence of differences between the profiles of volatile compounds of various types of chocolates enriched with fruit or vegetable powders. Thus, the enrichment of dark and milk chocolates with BLUB, RASB, BLCB, POME and BEET powders seemed to be an interesting approach to enhance bioactivity and to enrich the sensory features of various chocolate types.

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Gluten-free crispbread with freeze-dried blackberry: quality and mineral composition

CyTA - Journal of Food ◽

10.1080/19476337.2019.1660725 ◽

2019 ◽

Vol 17 (1) ◽

pp. 841-849 ◽

Cited By ~ 1

Author(s):

Renata Różyło ◽

Monika Wójcik ◽

Beata Biernacka ◽

Dariusz Dziki

Keyword(s):

Mineral Composition ◽

Gluten Free ◽

Freeze Dried

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Three-Dimensional Reconstruction Using Stereo Pairs from Serial Thick Sections

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100080249 ◽

1977 ◽

Vol 35 ◽

pp. 562-563

Author(s):

Robert Glaeser ◽

Thomas Bauer ◽

David Grano

Keyword(s):

Three Dimensional ◽

Dimensional Structure ◽

Serial Sections ◽

Thin Sections ◽

3 Dimensional ◽

Transmission Electron ◽

Freeze Dried ◽

Dimensional Reconstruction ◽

Stereo Imagery ◽

Whole Mounts

In transmission electron microscopy, the 3-dimensional structure of an object is usually obtained in one of two ways. For objects which can be included in one specimen, as for example with elements included in freeze- dried whole mounts and examined with a high voltage microscope, stereo pairs can be obtained which exhibit the 3-D structure of the element. For objects which can not be included in one specimen, the 3-D shape is obtained by reconstruction from serial sections. However, without stereo imagery, only detail which remains constant within the thickness of the section can be used in the reconstruction; consequently, the choice is between a low resolution reconstruction using a few thick sections and a better resolution reconstruction using many thin sections, generally a tedious chore. This paper describes an approach to 3-D reconstruction which uses stereo images of serial thick sections to reconstruct an object including detail which changes within the depth of an individual thick section.

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Scanning and Transmission Microscopy of Nematocyst Batteries in Epitheliomuscular Cells of Hydra

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066097 ◽

1971 ◽

Vol 29 ◽

pp. 410-411 ◽

Cited By ~ 1

Author(s):

Jane A. Westfall ◽

S. Yamataka ◽

Paul D. Enos

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Osmium Tetroxide ◽

External Surface ◽

Three Dimensional ◽

Surface Structures ◽

Transmission Microscopy ◽

Transmission Electron ◽

Freeze Dried ◽

Scanning Electron

Scanning electron microscopy (SEM) provides three dimensional details of external surface structures and supplements ultrastructural information provided by transmission electron microscopy (TEM). Animals composed of watery jellylike tissues such as hydras and other coelenterates have not been considered suitable for SEM studies because of the difficulty in preserving such organisms in a normal state. This study demonstrates 1) the successful use of SEM on such tissue, and 2) the unique arrangement of batteries of nematocysts within large epitheliomuscular cells on tentacles of Hydra littoralis.Whole specimens of Hydra were prepared for SEM (Figs. 1 and 2) by the fix, freeze-dry, coat technique of Small and Màrszalek. The specimens were fixed in osmium tetroxide and mercuric chloride, freeze-dried in vacuo on a prechilled 1 Kg brass block, and coated with gold-palladium. Tissues for TEM (Figs. 3 and 4) were fixed in glutaraldehyde followed by osmium tetroxide. Scanning micrographs were taken on a Cambridge Stereoscan Mark II A microscope at 10 KV and transmission micrographs were taken on an RCA EMU 3G microscope (Fig. 3) or on a Hitachi HU 11B microscope (Fig. 4).

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Characterization of microtubules by dark-field STEM and replication

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010008506x ◽

1991 ◽

Vol 49 ◽

pp. 152-153

Author(s):

S.B. Andrews ◽

R.D. Leapman ◽

P.E. Gallant ◽

T.S. Reese

Keyword(s):

Protein Interactions ◽

Low Dose ◽

Unit Length ◽

Dark Field ◽

Carbon Films ◽

Microtubule Associated Proteins ◽

Molecular Weights ◽

Freeze Dried ◽

Protein Motors ◽

Associated Proteins

As part of a study on protein interactions involved in microtubule (MT)-based transport, we used the VG HB501 field-emission STEM to obtain low-dose dark-field mass maps of isolated, taxol-stabilized MTs and correlated these micrographs with detailed stereo images from replicas of the same MTs. This approach promises to be useful for determining how protein motors interact with MTs. MTs prepared from bovine and squid brain tubulin were purified and free from microtubule-associated proteins (MAPs). These MTs (0.1-1 mg/ml tubulin) were adsorbed to 3-nm evaporated carbon films supported over Formvar nets on 600-m copper grids. Following adsorption, the grids were washed twice in buffer and then in either distilled water or in isotonic or hypotonic ammonium acetate, blotted, and plunge-frozen in ethane/propane cryogen (ca. -185 C). After cryotransfer into the STEM, specimens were freeze-dried and recooled to ca.-160 C for low-dose (<3000 e/nm2) dark-field mapping. The molecular weights per unit length of MT were determined relative to tobacco mosaic virus standards from elastic scattering intensities. Parallel grids were freeze-dried and rotary shadowed with Pt/C at 14°.

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The Effects of Drying Techniques on Clay-Rich Soil Texture

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052341 ◽

1974 ◽

Vol 32 ◽

pp. 466-467

Author(s):

T. G. Naymik

Keyword(s):

Critical Point ◽

Liquid Nitrogen ◽

Liquid Nitrogen Temperature ◽

Drying Methods ◽

Air Drying ◽

Freeze Dried ◽

Critical Point Drying ◽

Set Up ◽

The Relationship ◽

Quartz Grains

Three techniques were incorporated for drying clay-rich specimens: air-drying, freeze-drying and critical point drying. In air-drying, the specimens were set out for several days to dry or were placed in an oven (80°F) for several hours. The freeze-dried specimens were frozen by immersion in liquid nitrogen or in isopentane at near liquid nitrogen temperature and then were immediately placed in the freeze-dry vacuum chamber. The critical point specimens were molded in agar immediately after sampling. When the agar had set up the dehydration series, water-alcohol-amyl acetate-CO2 was carried out. The objectives were to compare the fabric plasmas (clays and precipitates), fabricskeletons (quartz grains) and the relationship between them for each drying technique. The three drying methods are not only applicable to the study of treated soils, but can be incorporated into all SEM clay soil studies.

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Oncornavirus assembly at the cell surface revealed in replicas of freeze-dried cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100082637 ◽

1978 ◽

Vol 36 (2) ◽

pp. 354-355

Author(s):

Anthony Demsey ◽

Christopher W. Stackpole

Keyword(s):

Cell Surface ◽

Surface Membrane ◽

Viral Origin ◽

Intact Cells ◽

Structural Formation ◽

Virus Core ◽

Freeze Dried ◽

Cacodylate Buffer ◽

Surface Replica ◽

Leukemia Viruses

The murine leukemia viruses are type-C oncornaviruses, and their release from the host cell involves a “budding” process in which the newly-forming, RNA-containing virus core becomes enveloped by modified cell surface membrane. Previous studies revealed that the released virions possess a dense array of 10 nm globular projections (“knobs”) on this envelope surface, and that these knobs contain a 70, 000 MW glycoprotein (gp70) of viral origin. Taking advantage of this distinctive structural formation, we have developed a procedure for freeze-drying and replication of intact cells which reveals surface detail superior to other surface replica techniques, and sufficient to detect even early stages of virus budding by localized aggregation of these knobs on the cell surface.Briefly, cells growing in monolayer are seeded onto round glass coverslips 10-12 mm in diameter. After a period of growth, cells are fixed in situ for one hour, usually with 1% OsO4 in 0. 1 M cacodylate buffer, and rinsed in distilled water.

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Conformation of eukaryotic ribosomal RNAs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100076561 ◽

1983 ◽

Vol 41 ◽

pp. 592-593

Author(s):

M. Boublik ◽

G. Thornton ◽

G. Oostergetel ◽

J.F. Hainfeld ◽

J.S. Wall

Keyword(s):

Molecular Weight ◽

Mass Measurement ◽

Carbon Film ◽

Structural Complexity ◽

Scanning Transmission Electron Microscope ◽

Electron Microscopic ◽

Pure Nitrogen ◽

Freeze Dried ◽

Scanning Transmission ◽

Partially Unfolded

Understanding the structural complexity of ribosomes and their role in protein synthesis requires knowledge of the conformation of their components - rRNAs and proteins. Application of dedicated scanning transmission electron microscope (STEM), electrical discharge of the support carbon film in an atmosphere of pure nitrogen, and determination of the molecular weight of individual rRNAs enabled us to obtain high resolution electron microscopic images of unstained freeze-dried rRNA molecules from BHK cells in a form suitable for evaluation of their 3-D structure. Preliminary values for the molecular weight of 28S RNA from the large and 18S RNA from the small ribosomal subunits as obtained by mass measurement were 1.84 x 106 and 0.97 x 106, respectively. Conformation of rRNAs consists, in general, of alternating segments of intramolecular hairpin stems and single stranded loops in a proportion which depends on their ionic environment, the Mg++ concentration in particular. Molecules of 28S RNA (Fig. 1) and 18S RNA (not shown) obtained by freeze-drying from a solution of 60 mM NH+4 acetate and 2 mM Mg++ acetate, pH 7, appear as partially unfolded coils with compact cores suggesting a high degree of ordered secondary structure.

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Scanning Electron Microscopy-cuticular Lesions on the Roundworm Ascaris Suum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006756x ◽

1970 ◽

Vol 28 ◽

pp. 114-115

Author(s):

P. A. Madden ◽

W. R. Anderson

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Freeze Drying ◽

Room Temperature ◽

Secondary Electron ◽

Distilled Water ◽

Freeze Dried ◽

Silver Paint ◽

To Come ◽

Scanning Electron

The intestinal roundworm of swine is pinkish in color and about the diameter of a lead pencil. Adult worms, taken from parasitized swine, frequently were observed with macroscopic lesions on their cuticule. Those possessing such lesions were rinsed in distilled water, and cylindrical segments of the affected areas were removed. Some of the segments were fixed in buffered formalin before freeze-drying; others were freeze-dried immediately. Initially, specimens were quenched in liquid freon followed by immersion in liquid nitrogen. They were then placed in ampuoles in a freezer at −45C and sublimated by vacuum until dry. After the specimens appeared dry, the freezer was allowed to come to room temperature slowly while the vacuum was maintained. The dried specimens were attached to metal pegs with conductive silver paint and placed in a vacuum evaporator on a rotating tilting stage. They were then coated by evaporating an alloy of 20% palladium and 80% gold to a thickness of approximately 300 A°. The specimens were examined by secondary electron emmission in a scanning electron microscope.

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Conformational Transitions in Escherichia coli Ribosomal RNAs as Visualized by Dedicated STEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102961 ◽

1988 ◽

Vol 46 ◽

pp. 176-177

Author(s):

J.S. Wall ◽

V. Maridiyan ◽

S. Tumminia ◽

J. Hairifeld ◽

M. Boublik

Keyword(s):

Ionic Strength ◽

Three Dimensional ◽

Conformational Transitions ◽

Dark Field ◽

Dimensional Structure ◽

Ribosomal Rnas ◽

Field Mode ◽

Freeze Dried ◽

High Resolution Images ◽

Low Ionic Strength

The high contrast in the dark-field mode of dedicated STEM, specimen deposition by the wet film technique and low radiation dose (1 e/Å2) at -160°C make it possible to obtain high resolution images of unstained freeze-dried macromolecules with minimal structural distortion. Since the image intensity is directly related to the local projected mass of the specimen it became feasible to determine the molecular mass and mass distribution within individual macromolecules and from these data to calculate the linear density (M/L) and the radii of gyration.2 This parameter (RQ), reflecting the three-dimensional structure of the macromolecular particles in solution, has been applied to monitor the conformational transitions in E. coli 16S and 23S ribosomal RNAs in solutions of various ionic strength.In spite of the differences in mass (550 kD and 1050 kD, respectively), both 16S and 23S RNA appear equally sensitive to changes in buffer conditions. In deionized water or conditions of extremely low ionic strength both appear as filamentous structures (Fig. la and 2a, respectively) possessing a major backbone with protruding branches which are more frequent and more complex in 23S RNA (Fig. 2a).

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