IMMUNOCHEMICAL STUDY OF A BACTERIAL ENDOTOXIN: SHIGELLA FLEXNERI TYPE Z

The endotoxins of the Gram-negative bacteria have similar biological and chemical properties. The toxic antigen of Shigella flexneri Type Z was selected as a representative endotoxin, and it was confirmed that the antigen consists of a polysaccharide conjugated with phospholipid and protein. By the technique of zone electrophoresis, the polysaccharide of the purified endotoxin was shown to be conjugated with each of three different proteins, and each conjugate proved toxic and antigenic for the rabbit. Two of the protein conjugates were digested by trypsin and the released polysaccharide appeared to conjugate with the remaining trypsin-resistant protein. Immunological analysis revealed that the purified toxic antigen is heterogeneous and that the polysaccharide and protein components possessed serological activity. The trypsin-treated toxin had a single electrophoretic zone and its precipitation in gel suggested immunological purity. Proteolytic treatment of the endotoxin did not destroy its toxicity or antigenicity for the rabbit.

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Effect of Gutting on Microbial Loads, Sensory Properties, and Volatile and Biogenic Amine Contents of European Hake (Merluccius merluccius var. mediterraneus) Stored in Ice

Journal of Food Protection ◽

10.4315/0362-028x-72.8.1671 ◽

2009 ◽

Vol 72 (8) ◽

pp. 1671-1676 ◽

Cited By ~ 16

Author(s):

SONIA BAIXAS-NOGUERAS ◽

SARA BOVER-CID ◽

M. TERESA VECIANA-NOGUÉS ◽

M. CARMEN VIDAL-CAROU

Keyword(s):

Shelf Life ◽

Quality Indicators ◽

Biogenic Amine ◽

Chemical Properties ◽

Ice Storage ◽

Gram Negative Bacteria ◽

Merluccius Merluccius ◽

Gram Negative ◽

European Hake ◽

And Chemical Properties

The effect of gutting on sensory, microbiological, and chemical properties of European hake (Merluccius merluccius var. mediterraneus) stored in ice was studied. Gutting of hake noticeably affected the development of gram-negative bacteria: counts of Enterobacteriaceae, Shewanella putrefaciens, and Pseudomonas throughout ice storage were higher in gutted than in ungutted samples. These differences in microbial loads were also reflected in the lower sensory scores of both raw and cooked hake, in the quicker trimethylamine accumulation, and in the higher contents of putrescine, cadaverine, tyramine, and histamine found in gutted hake. All of the fish quality indicators studied showed that gutting made hake more susceptible to spoilage during ice storage and decreased its shelf life by 4 days.

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Facile Synthesis of Natural Anise-Based Nanoemulsions and Their Antimicrobial Activity

Polymers ◽

10.3390/polym13122009 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2009

Author(s):

Ola A. Abu Ali ◽

Mehrez E. El-Naggar ◽

Mohamed S. Abdel-Aziz ◽

Dalia I. Saleh ◽

Mohamed. A. Abu-Saied ◽

...

Keyword(s):

Antimicrobial Agents ◽

Reducing Sugars ◽

Total Phenolics ◽

Antioxidant Activities ◽

Chemical Properties ◽

Geranyl Acetate ◽

Gram Negative Bacteria ◽

Facile Synthesis ◽

Gram Positive Bacteria ◽

And Chemical Properties

Anise oil was prepared in its nanoemulsion form to facilitate the penetration of microbial walls, causing microbe mortality. The penetration occurred easily owing to the reduction in its size (nm). Nanoemulsions with different concentrations of anise oil were prepared using lecithin as an emulsifying agent with the aid of an ultra-sonification process. Their morphological and chemical properties were then characterized. The promising constituents were l-Menthone (11.22%), Gurjunene (6.78%), Geranyl acetate (4.03%), Elemene (3.93%), Geranyl tiglate (3.53%), geraniol (3.48%), linalool (0.17%) as well as camphene (0.12%). Different concentrations of prepared anise oil in micro and nanoemulsions were tested as antimicrobial agents against Gram-positive bacteria (Staphylococcus aureus), Gram-negative bacteria (Escherichia coli), yeast (Candida albicans) and fungi (Asperigillus niger). The findings illustrated that the anise oil-based nanoemulsion exhibited better results. Different biochemical and biological evaluations of anise oil nanoemulsions were conducted, including determining killing times, antioxidant activities (using three different methods), and total phenolics. A trial to estimate the mode of action of anise oil-based nanoemulsion as an antimicrobial agent against S. aureus and C. albicans was performed via studying the release of reducing sugars and protein and conducting scanning electron microscopy.

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Preparation characterization and biological activity of some new tetra - azo compounds

10.32792/thi/sc/vol.1.is.2.05 ◽

2008 ◽

pp. 35-44

Keyword(s):

Ph Value ◽

Chemical Properties ◽

Azo Compounds ◽

Gram Negative Bacteria ◽

Gram Positive Bacteria ◽

Phenol Derivatives ◽

Visible Spectra ◽

Physical And Chemical ◽

And Chemical Properties

In this paper , preparation and characterization of some tetra azo compounds .Azo coupling of 3`,3,4`,4- tetra amino biphenyl with phenol and some phenol derivatives in alkaline solution gave azo dyes. I.R and U.V. visible spectra were recorded to identify the three azo compounds prepared . Some physical and chemical properties such as molar absorption coefficient in different pH value and maximum absorption λ maxwere investigated. The biological effect of these dye against two gram positive Bacteria (S.aureuse) and other two gram negative Bacteria (P.aeruginosa) is presented .

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Copper: Synthesis Techniques in Nanoscale and Powerful Application as an Antimicrobial Agent

Journal of Nanomaterials ◽

10.1155/2015/415238 ◽

2015 ◽

Vol 2015 ◽

pp. 1-10 ◽

Cited By ~ 19

Author(s):

B. A. Camacho-Flores ◽

O. Martínez-Álvarez ◽

M. C. Arenas-Arrocena ◽

R. Garcia-Contreras ◽

L. Argueta-Figueroa ◽

...

Keyword(s):

Chemical Properties ◽

Inhibitory Effect ◽

Inorganic Nanoparticles ◽

Metal Particles ◽

Gram Negative Bacteria ◽

Physical And Chemical Properties ◽

Optimal Parameters ◽

Composites Materials ◽

Physical And Chemical ◽

And Chemical Properties

Nanosized metal particles show specific physical and chemical properties that allow the creation of new composites materials, which are important for multiple applications in biology and medicine such as infections control. Metal nanoparticles, mainly copper, exhibit excellent inhibitory effect on Gram-positive and Gram-negative bacteria; therefore the exploration about the efficient, economical, and friendly environmental technics to synthesize inorganic nanoparticles is imperative. In this work a brief overview of the several methods is made including the comparison of the methods, mainly between sonochemical, microwave, and chemical routes. It allows determining the optimal parameters and technical conditions to synthesize copper nanoparticles with physical and chemical properties suitable for the oral bacterial inhibition.

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Statistical criteria of stellar population types

Symposium - International Astronomical Union ◽

10.1017/s0074180900053304 ◽

1966 ◽

Vol 24 ◽

pp. 101-110

Author(s):

W. Iwanowska

Keyword(s):

Stellar Population ◽

Chemical Properties ◽

Spectrophotometric Study ◽

Physical And Chemical Properties ◽

Population Type ◽

The Galaxy ◽

Distribution Parameters ◽

Physical And Chemical ◽

Statistical Criteria ◽

And Chemical Properties

In connection with the spectrophotometric study of population-type characteristics of various kinds of stars, a statistical analysis of kinematical and distribution parameters of the same stars is performed at the Toruń Observatory. This has a twofold purpose: first, to provide a practical guide in selecting stars for observing programmes, second, to contribute to the understanding of relations existing between the physical and chemical properties of stars and their kinematics and distribution in the Galaxy.

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The microstructure of a TiB2/Ti-47 Al composite material

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100155347 ◽

1989 ◽

Vol 47 ◽

pp. 674-675

Author(s):

O. Popoola ◽

A.H. Heuer ◽

P. Pirouz

Keyword(s):

Composite Material ◽

Ion Beam ◽

Chemical Properties ◽

Intermetallic Alloys ◽

Transmission Electron ◽

Diamond Polishing ◽

Al Composite ◽

The Matrix ◽

Argon Ion ◽

And Chemical Properties

The addition of fibres or particles (TiB2, SiC etc.) into TiAl intermetallic alloys could increase their toughness without compromising their good high temperature mechanical and chemical properties. This paper briefly discribes the microstructure developed by a TiAl/TiB2 composite material fabricated with the XD™ process and forged at 960°C.The specimens for transmission electron microscopy (TEM) were prepared in the usual way (i.e. diamond polishing and argon ion beam thinning) and examined on a JEOL 4000EX for microstucture and on a Philips 400T equipped with a SiLi detector for microanalyses.The matrix was predominantly γ (TiAl with L10 structure) and α2(TisAl with DO 19 structure) phases with various morphologies shown in figure 1.

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Ultrastructure of periplasmic bodies in gram-negative bacteria

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100160753 ◽

1990 ◽

Vol 48 (3) ◽

pp. 640-641

Author(s):

Xie Nianming ◽

Ding Shaoqing ◽

Wang Luping ◽

Yuan Zenglin ◽

Zhan Guolai ◽

...

Keyword(s):

Electron Microscope ◽

Campylobacter Jejuni ◽

Proteus Mirabilis ◽

Shigella Flexneri ◽

Morphological Description ◽

Gram Negative Bacteria ◽

Periplasmic Space ◽

Clostridium Tetani ◽

Gram Negative ◽

Brucella Canis

Perhaps the data about periplasmic enzymes are obtained through biochemical methods but lack of morphological description. We have proved the existence of periplasmic bodies by electron microscope and described their ultrastructures. We hope this report may draw the attention of biochemists and mrophologists to collaborate on researches in periplasmic enzymes or periplasmic bodies with each other.One or more independent bodies may be seen in the periplasmic space between outer and inner membranes of Gram-negative bacteria, which we called periplasmic bodies. The periplasmic bodies have been found in seven species of bacteria at least, including the Pseudomonas aeroginosa. Shigella flexneri, Echerichia coli. Yersinia pestis, Campylobacter jejuni, Proteus mirabilis, Clostridium tetani. Vibrio cholerae and Brucella canis.

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Tailoring microstructures of materials through biomimetics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148332 ◽

1993 ◽

Vol 51 ◽

pp. 500-501

Author(s):

Mehmet Sarikaya ◽

Ilhan A. Aksay

Keyword(s):

Chemical Properties ◽

Design And Synthesis ◽

Structure Sensitive ◽

Macro Scale ◽

Methods Of Synthesis ◽

Successive Level ◽

Engineering Materials ◽

Physical And Chemical ◽

And Chemical Properties ◽

Synthesis Of Materials

Biomimetics involves investigation of structure, function, and methods of synthesis of biological composite materials. The goal is to apply this information to the design and synthesis of materials for engineering applications.Properties of engineering materials are structure sensitive through the whole spectrum of dimensions from nanometer to macro scale. The goal in designing and processing of technological materials, therefore, is to control microstructural evolution at each of these dimensions so as to achieve predictable physical and chemical properties. Control at each successive level of dimension, however, is a major challenge as is the retention of integrity between successive levels. Engineering materials are rarely fabricated to achieve more than a few of the desired properties and the synthesis techniques usually involve high temperature or low pressure conditions that are energy inefficient and environmentally damaging.In contrast to human-made materials, organisms synthesize composites whose intricate structures are more controlled at each scale and hierarchical order.

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