scholarly journals THE EFFECT OF WETTING AGENTS ON THE GROWTH OF TUBERCLE BACILLI

1948 ◽  
Vol 88 (1) ◽  
pp. 81-88 ◽  
Author(s):  
René J. Dubos ◽  
Gardner Middlebrook
Keyword(s):  
Aqueous Media ◽  
Tween 80 ◽  
Unesterified Fatty Acid ◽  
Sorbitan Monooleate ◽  
Bacterial Surface ◽  
Water Dispersible ◽  
Morphological Aspects ◽  
Surface Active Agents ◽  
Surface Active ◽  
Wetting Agents

Tween 80 and Triton A20 are two water-dispersible, non-ionic, surface-active agents which favor dispersed growth of tubercle bacilli in aqueous media probably by wetting the bacterial surface. Tween 80 is a polyoxyethylene ester of sorbitan monooleate and is liable to enzymatic hydrolysis by lipases. Triton A20 in an arylalkyl polyether of phenol which appears resistant to the known enzymes of animal tissues. Tween 80 loses its ability to disperse cultures of tubercle bacilli in media containing serum; Triton A20 does not. Tween 80 increases the yield of growth, probably by supplying oleic acid to the bacilli; Triton A20 does not. In concentrations sufficient to cause dispersed browth, Tween 80 (purified by removal of unesterified fatty acid) and Triton A20 are completely innocuous for virulent tubercle bacilli. However, Triton A20 exhibits a marked toxic effect on the avirulent variants of mammalian strains; Tween 80 does not. The two wetting agents also differ in their effects on the morphological aspects of the bacterial cultures. Whereas Triton A20 prevents the formation of large amorphous bacillary clumps, it is less effective in preventing the orientation of the virulent bacilli resulting in the formation of long bacillary strands. Tween 80 on the contrary prevents also the formation of these cords of bacilli and exerts therefore a more effective dispersing effect on cultures of virulent tubercle bacilli.

Effect of surface active agents on the production of biopesticides using wastewater sludge as a raw material

2001 ◽  
Vol 44 (10) ◽  
pp. 253-259 ◽  
Author(s):  
A.S. Vidyarthi ◽  
R.D. Tyagi ◽  
J.R. Valéro
Keyword(s):  
Bacillus Thuringiensis ◽  
Shake Flask ◽  
Spruce Budworm ◽  
Tween 80 ◽  
Wastewater Sludge ◽  
Raw Material ◽  
Viable Cells ◽  
Surface Active Agents ◽  
Surface Active ◽  
Effect Of Surface

Effect of surface active agents on the production of Bacillus thuringiensis based biopesticides using secondary wastewater sludge as a raw material was studied. The experiments were conducted in a shake flask and nine different commercial surface active agents were used at a concentration of 0.2% (v/v). The sludge samples after addition of surface active agents were sterilised at 121°C for 30 min. The progress of biopesticide production was monitored by measuring viable cells and viable spores counts. The entomotoxicity was determined through bioassay against 3rd instar larvae of spruce budworm. ATPLUS 522, Tween 80 and Tween 85 increased the entomotoxicity potential in comparison to the control. The highest increase of 24% in entomotoxicity was observed when sludge was fortified with Tween 80.

scholarly journals SUSTAINED HYPERLIPEMIA INDUCED IN RABBITS BY MEANS OF INTRAVENOUSLY INJECTED SURFACE-ACTIVE AGENTS

1951 ◽  
Vol 93 (4) ◽  
pp. 373-383 ◽  
Author(s):  
Aaron Kellner ◽  
James W. Correll ◽  
Anthony T. Ladd
Keyword(s):  
Intravenous Injection ◽  
Total Lipid ◽  
Lipid Content ◽  
Total Lipid Content ◽  
Tween 80 ◽  
Normal Diet ◽  
Blood Cholesterol ◽  
Surface Active Agents ◽  
Surface Active

The intravenous injection of the surface-active agents Tween 80 and Triton A20 into rabbits fed a normal diet resulted in marked and sustained elevations of the cholesterol, phospholipid, and total lipid content of their blood. The increase in phospholipid in general paralleled that of the blood cholesterol. The implications of the findings are briefly discussed.

Impacts of Surface-Active Agents on the Crystal Structure of Nano Manganese Oxide

2013 ◽  
Vol 798-799 ◽  
pp. 125-129
Author(s):  
Fu Yun Li ◽  
Jing Wang ◽  
Ying Yang Qin ◽  
Li Zhen Yang
Keyword(s):  
Crystal Structure ◽  
Manganese Oxide ◽  
Hydrothermal Method ◽  
Manganese Oxides ◽  
Surface Active Agent ◽  
Active Agent ◽  
Tween 80 ◽  
Surface Active Agents ◽  
Surface Active ◽  
Addition Amount

The nano manganese oxides were prepared with the hydrothermal method by adding surface-active agent. The influence of the type and addition amount of surface-active agent on the preparation of nano manganese oxides was studied. The products were characterized with XRD. Experimental results show that MnOOH is obtained at 180°C with the addition of N,N,N-trimethyl-1-dodecanaminium bromide, and Mn3O4is obtained at 180 °C with OP Emulsifier or Tween-80 added. Different addition amount of surface-active agent would have diverse effects on the purity of products.

scholarly journals VIRULENCE AND MORPHOLOGICAL CHARACTERISTICS OF MAMMALIAN TUBERCLE BACILLI

1947 ◽  
Vol 86 (2) ◽  
pp. 175-184 ◽  
Author(s):  
Gardner Middlebrook ◽  
René J. Dubos ◽  
Cynthia Pierce
Keyword(s):  
Oleic Acid ◽  
Morphological Characteristics ◽  
Tween 80 ◽  
Water Dispersible ◽  
Varying Thickness ◽  
Solid Media ◽  
Solid Agar ◽  
Surface Active ◽  
Morphological Differences

Experimental infection of the mouse can be used for the determination of virulence of cultures of mammalian tubercle bacilli. The relative virulence of such cultures for the mouse is approximately the same as for the guinea pig. Cultures of virulent and avirulent variants of mammalian tubercle bacilli grown in the depth of Tween 80-albumin liquid medium, on the surface of solid agar modifications of this medium, and on the surface of a liquid modification of this medium exhibit consistent morphological differences. All virulent cultures tend to form microscopically demonstrable serpentine cords of varying thickness and length consisting of highly acid-fast bacilli oriented in parallel along the long axis of the cord. The formation of cords appears to be an important factor in conditioning the ability of cultures to spread on the surface of liquid and solid media. It can be inhibited by the addition to the medium of the surface-active water-dispersible oleic acid ester, Tween 80. Avirulent variant bacilli grow in a more or less non-oriented fashion. They have never been observed to form cords under any condition of growth and are much less acid-fast than the virulent cultures when grown in Tween-albumin medium. Two strains of mammalian tubercle bacilli which are intermediate in degree of virulence between the fully virulent and the avirulent variants also exhibit intermediate morphological characteristics.

scholarly journals THE INFLUENCE OF INTRAVENOUSLY ADMINISTERED SURFACE-ACTIVE AGENTS ON THE DEVELOPMENT OF EXPERIMENTAL ATHEROSCLEROSIS IN RABBITS

1951 ◽  
Vol 93 (4) ◽  
pp. 385-398 ◽  
Author(s):  
Aaron Kellner ◽  
James W. Correll ◽  
Anthony T. Ladd
Keyword(s):  
Blood Lipids ◽  
Great Increase ◽  
Tween 80 ◽  
Experimental Atherosclerosis ◽  
Blood Cholesterol ◽  
Intravenous Injections ◽  
Surface Active Agents ◽  
Surface Active ◽  
Relationship Of ◽  
The Relationship

A study was made of the relationship of blood lipids to the development of experimental atherosclerosis. Rabbits fed a diet containing cholesterol were found to develop hyperlipemia characterized by a great increase in blood cholesterol and a much lesser increase in blood phospholipids; after several weeks they manifested conspicuous atherosclerosis of the aorta, as has often been observed by others. Comparable rabbits fed the same diets containing added cholesterol were given in addition repeated intravenous injections of the surface-active agents Tween 80 and Triton A20; these animals developed hyperlipemia which was characterized by a great increase in blood cholesterol and an equivalent or even greater increase in phospholipids, and they had much less atherosclerosis than did the control rabbits fed cholesterol alone. In further experiments it was observed that repeated intravenous injections of Tween 80 did not result in resorption of previously induced atherosclerosis in rabbits. The findings are discussed in relation to the pathogenesis of natural and experimental atherosclerosis.

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