ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb02579.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb02580.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Disc‐diffusion, agar‐dilution and microdilution methods were compared for testing the antibiotic sensitivity of anaerobic bacteria. Eight antibiotics and 31 test organisms were used. There was a poor correlation between MIC values obtained by the agar‐dilution and microdilution procedures. The test organisms showed an apparently increased sensitivity to the antibiotics when tested by the agar‐dilution, as compared with the microdilution, procedures. Columbia Blood Agar and Thioglycollate Haemin agar, were evaluated for the disc‐diffusion and agardilution procedures. There was a poor correlation between the MIC values and inhibition zone diameters for the two media, with lower MIC values and larger zones on Thioglycollate Ha

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb02581.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Disinfection capacity determinations using solutions prepared from effervescent tablets of sodium dichloroisocyanurate (NaDCC) and from solutions of sodium hypochlorite (NaOCI) indicated high activity against a range of organisms, which represent adequate safety margins for disinfection. NaDCC showed significantly higher activity than NaOCl solution against all bacterial species tested but activity againstCandida albicanswas similar. Results indicate that differences in activity between NaDCC and NaOC1 formulations are not entirely due to pH effects and that fundamental differences exist between properties and mode of action of the 2 hypochlorite systems.

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb02582.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

During the ponding of Sitka spruce in lake water there was a change from a diverse, aerobic flora (16 species) to a restricted, facultatively anaerobic flora (1 or 2 species). This change corresponded with a marked increase in the degradation of pectin and a concomitant increase in the permeability of the wood to preservatives. A strain ofEnterobacter cloacae(NCPPB 2909) isolated during ponding, synthesized an extracellular and intracellular polygalacturonase (PG) and an intracellular polygalacturonate trans‐eliminase (PGTE). Both PG and PGTE were growth–linked; extracellular PG was produced initially and then replaced by intracellular PG and PGTE. A change in the pH value of the medium did not alter the relative synthesis of enzyme. Reduced oxygen tension retarded growth but had no effect on enzyme activities. PG and PGTE ofE. cloacaewere shown to have specific ion requirements and when tap‐water was used in the preparation of a medium growth did not occur. The results are discussed in relation to an artificial system of sprinkling water, seeded with known species of bacteria, on to spruce wood in order to control the rate of pectin degradation and thus the permeability of the wood to preserva

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb02583.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Bacteria on plant surfaces were examined using epifluorescence, bright‐field microscopy and an impression technique. Staining bacteria directly on the plant surface with phenolic aniline blue was found to be the best method to use for the determination of bacterial density. The effect on the estimation of population density of pretreatment of the plant with agents such as methanol and eosin yellowish was investigated. The average sizes of the bacterial populations on two freshwater plants,Rorippa and Lemna, estimated after staining by this method, were 5 times 106and 9 times 106bacteria cm‐zrespectiv

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb02584.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

l‐Serine dehydratase (SD) was produced to the extent of only 0·04 international unit (iu) per mg dry weight byAeromonos punctataNRRL B‐928 when grown on a chemically defined medium. Addition of 2% (w/v)l‐serine to this medium increased SD ten‐fold or more, indicating a significant inductive effect.d‐Serine was toxic to the organism, making weights and enzyme titres uncertain, butdl‐serine induced a specific activity of SD at least equal to that from thelenantiomorph. With complex media containing beef extract, the toxic effect ofd‐serine was partially overcome, and sufficient growth was obtained to permit reliable analytical figures;d‐serine induced slightly better specific activities than thelisomer.dl‐Serine at 2% concentration induced a specific activity of 1·2 iu/mg, twice that ofl

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb02585.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Taurolin, a broad spectrum bactericidal agent, protected experimental animals from the lethal effects ofEscherichia coliandBacteroides fragilisendotoxin. Taurolin also prevented the pyrexic response of rabbits to TAB vaccine. Results suggest that Taurolin exerts its antiendotoxic effect by direct reaction with the endotoxin molecule.

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb02586.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

The methods used for concentrating animal viruses from drinking water were found to be unsuitable for the concentration of bacteriophages from natural waters. The factors affecting recovery were investigated and a concentration procedure devised which is amenable to larger scale and field use. This procedure involves: (1) passage of the water through a sand filter; (2) removal of dissolved organic material with an anion exchange resin; (3) addition of MgCl2to a final concentration of 5 times 10‐4m; (4) adjustment of the pH value to 3°8; (5) adsorption of the bacteriophages on to fibre glass and cellulose nitrate filters; (6) elution of bound phage with 3% (w/v) beef extract, and (7) concentration by ultrafiltration of the resulting eluates. Using this procedure a wide range of test bacteriophages was concentrated from 41 to 5 ml with recoveries ranging from 18–80%—concentration factors of 200–

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb02587.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

An aerobic mesophilicPseudomonassp. isolated from activated sludge degraded different cellulosic materials to varying‐degrees. The degradability was mostly influenced by the lignin content and the crystalline nature of the substrate. Filter paper and cotton fibres, containing little lignin, were degraded maximally. Lignin‐richPinusandLarixneedles were digested to a lesser extent. There was a difference between natural substrates and substrates that had undergone industrial treatment. At maximal protein production, the isolate converted 11–40% (w/w) of cellulosic substrates into proteins. Alkali treatment of the substrates had only little effect. Cellulose contained in pig‐waste was also degraded by the isolate. At first there was a period of protein production, but after long incubation, the efficiency of conversion of cellulose to protein de

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb02588.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY