摘要:

The effects of organic and inorganic nitrogen sources on lignocellulose degradation and production of acid precipitable polymeric lignin (APPL) by threeStreptomycesstrains (11A, 21B and 31C) were examined using sugar cane bagasse lignocellulose as substrate. All threeStreptomycesstrains caused lignocellulose weight losses ranging from 1·0 to 7·5%. The threeStreptomycesstrains depleted between 2·7 and 13·6% of the carbohydrate component and 2·6 to 18·0% of the lignin component of the lignocellulose, releasing between 2·0 and 17·3 mg APPL over a 1 week incubation period. On the other hand, inorganic nitrogen sources tended to inhibit lignocellulose degradation byStreptomycesstrains 11A and 31C while there was no significant effect on the ability of strain 21B to degrade lignocellulose. Generally, there was a noticeable enhancement in both lignin degradation and APPL production when the nitrogen source was organic rather than when the nitrogen source was in

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1988.tb01256.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Goats milk was examined for total viable bacteria and staphylococci (Baird‐Parker medium, Schleifer&Kramer's (SK) medium, SK medium with a reduced sodium azide content (SKR) and SK and SKR with 5% added sheep blood).Staphylococcus aureus, Staph. epidermidisandStaph. simulanswere the predominant species isolated overall. SK medium proved inhibitory with respect to the isolation ofStaph. capraeandStaph. chromogenes.This was reduced by plating on the modified SK media. Representative strains of each species isolated were examined for production of enterotoxins A‐E. Enterotoxin C alone was produced by 35% of theStaph. aureusstrains tested. None of the other staphylococcal species examined produced any of the known enterotox

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1988.tb01257.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

The effect of relative humidity (r.h.) (0%, 34% and 75%) and temperature (4, 15 and 25°C) on the desiccation survival ofPseudomonassp.,Acinetobacter calcoaceticus, a coryneform,Staphylococcussp., andStaphylococcus aureusattached to and grown on glass surfaces was studied. The survival of Gram‐negative and Gram‐positive species was similar. Bacterial survival was shortest at 25°C for all species studied, and in most cases longest at 4°C. The effect of r.h. on survival varied with species. The number of microcolonies and the number of cells within microcolonies forPseudomonassp. increased on the dry surfaces after 7 d incubation under all desiccation cond

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1988.tb01258.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Single dimension agar gel diffusion gradient plates were used to test the tolerance of several micro‐algae and cyanobacteria to five herbicides. Growth of most of the test organisms was prevented by terbutryn and diuron at concentrations between 1·1 and 2·8 μg/ml (minimum inhibitory concentration, MIC). Chlorpropham was intermediate in toxicity whilst monuron and atrazine generally gave higher MIC values (up to 17·1 μg/ml). The cyanobacteria were mostly more tolerant than the algae, but susceptibility to the herbicides was variable even between strains of an individual algal species. The gradient plate technique offers the advantages of simplicity and low cost in toxicity screening studies with herbicides or other biologically active chemicals and xenob

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1988.tb01259.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

A colony‐blot double‐stain method was developed to identify individual colonies ofVibrio choleraeserotype 01 (pandemic strain) in mixed bacterial cultures on solid media. The colonies are transferred from agar to nitrocellulose membranes for an enzyme‐linked immunosorbent assay (ELISA). Colonies of 01 vibrios bind the enzyme‐linked antibodies and appear as brown dots on the membranes; pale black dots develop at the site of replicated colonies of other bacteria as a result of the activity of endogenous oxidase‐like enzymes and serve as reference points. The results indicate that the colony‐blot double‐stain method is useful for the isolation of colonies ofV. choleraeserotype 01 in specimens that are heavily contaminated with n

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1988.tb01260.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Procedures to enumerate commonly used bacteriophage tracers in bivalve molluscan shellfish were evaluated. Bacteriophages specific toSerratia marcescens, Escherichia coliandEnterobacter cloacaecan be recovered from shellfish flesh by chloroform treatment of homogenates and subsequent clarification of samples by centrifugation. Bacteriophages were enumerated using a soft agar overlay technique. Hard clams appeared to release toxic compounds during homogenization which dramatically reduced counts ofEnt. clocaebacteriophage.

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1988.tb01261.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Rifamycin‐resistant strains ofMethylobacteriumAM1 are more sensitive to β‐lactam antibiotics, chloramphenicol, tetracycline, spectinomycin, puromycin, nalidixic acid, benzalkonium chloride andp‐fluorophenylalanine than are rifamycin‐sensitive strains. This suggests that mutation to rifamycin resistance is associated with a general increase in membrane permeability and may have a bearing on the use of rifamycin‐resistant mutants in genetic and biochemical studies of thi

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1988.tb01262.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

The thermophilic actinomycete,Thermomonospora curvata, released 16‐times the beta‐glucosidase when grown on protein‐extracted lucerne fibre compared with growth on cellobiose or purified cellulose. The intracellular and extracellular betaglucosidases had the same mol. wts (66 kD), but the extracellular enzyme had higher affinities for bothp‐nitrophenyl glucoside and cellobiose and was more resistant to thermal inact

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1988.tb01263.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Between July and December 1986, 18 strains of enteropathogenic serotypes ofEscherichia coliwere isolated from the Dal Lake water. Some of these strains were positive for colonization factor antigen. During the same period, 12 strains of heat‐labile enterotoxin‐producingE. coliwere also isolated, all of which were positive for colonization factor antigen I or II. This indicates faecal pollution of this recreational wa

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1988.tb01264.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

When rumen fluid was incubated in an artificial medium with timothy hay, plant cell wall digestion was decreased by the addition of trans‐p‐coumaric acid or transferulic acid. Both phenolic compounds inhibited methane production withp‐coumaric acid being the strongest inhi

ISSN:0266-8254    

DOI:10.1111/j.1472-765X.1988.tb01265.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY