摘要:

AbstractThe sporocidal activity of 1% solutions of five local anaesthetics and five preservatives (cetrimide, chlorocresol, chlorhexidine, phenoxyethanol and phenylmercuric nitrate) at their pharmacopeial concentrations, alone and in binary combinations was determined againstBacillus subtilisandAspergillus nigerspores at different temperature levels by the surface viable count technique. The sporicidal activity of all tested systems were temperature dependent.A. nigerspores were much more sensitive to the tested systems thanB. subtilisspores. The temperature at which 99% of all spores were killed after 30 min exposure time of the anaesthetics were calculated. In case of the local anaesthetics alone against spores ofA. nigerthe recorded temperatures were 30 °C for amethocaine, 45 °C for both amylocaine and cincochaine, 48 °C and 50 °C for lignocaine and procaine, respectively, in contrast to 58 °C in a control with saline solution. Much higher temperatures were calculated againstB. subtilisspores. Cincochaine was the most effective local anaesthetic with a recorded temperature of 60 °C, where 99% killed occurred. Amylocaine and amethocaine showed temperatures of 84 °C and 90 °C, respectively. Procaine, lignocaine as well saline solution as a control caused a 99% killing effect at temperatures higher than 100 °C.Among the 25 tested binary combinations of local anaesthetics and preservatives, the highest incidence of potentiation of the sporocidal activity was recorded with chlorocresol combinations, while other combinations of the four remaining preservatives showed different types of interactions at different per

ISSN:0233-111X    

DOI:10.1002/jobm.3620270802

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

摘要:

AbstractExtracellularly expressed exudates from pineapple fruit infected byCeratocystis paradoxawere partially purified and the exudate‐filtrate preparations were assayed for the presence of three hydrolytic enzymes. The preparations were found to contain cellulolytic and proteolytic enzymes when inoculated on carboxymethylcellulose and casein as substrates, respectively, while pectin‐methylesterases and polygalacturonases were detected in the exudate‐filtrate when apple pectin and sodium pectate were used as substrates, respectively. The activities and stabilities of these groups of enzymes were found to be optimal at pH 7.0 and at 30 °C. The exudates also exhibited macerating action when potato discs showed complete loss of coherence and maceration after a 24 hr incubation. More total reducing sugars were detected in exudates of infected fruit than those obtained from healthy

ISSN:0233-111X    

DOI:10.1002/jobm.3620270803

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

摘要:

AbstractDunaliella bioculata, a marine unicellular euryhaline green alga, accumulated interacellular glycerol as a response to increaed osmolality due to increased concentrations of NaCl, KCl or sucrose, but not ethylene glycol. A decrease in salinity, below the normal, of the outer medium resulted in a decrease in the intracellular glycerol. Glycerol was retained (NaCl salinization) or released (KCl salinization) by the alga. Glycerol production slightly depended on photosynthesis since it took place in the light and in the dark.

ISSN:0233-111X    

DOI:10.1002/jobm.3620270804

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

ISSN:0233-111X    

DOI:10.1002/jobm.3620270806

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

摘要:

AbstractThe extracellular lipase ofAcinetobacter calcoaceticus69 V was purified by hydrophobic interaction chromatography to homogeneity as suggested by gel electropheretic analysis.The lipase existed as a high molecular complex of about 300 kDa, with a subunit molecular weight of 30.5 kDa being obtained by SDS‐PAGE. The hydrodynamic molecular radious obtained by gel electrophoresis was 3.27 nm.The lipase had an isoelectric point of 5.5 and was stimulated by additions of deoxycholate. The activation energy for the hydrolysis ofp‐nitrophenyl palmitate was 39.9 kJ mol−1. Tri‐, di‐ and monoacylglycerols were hydrolyzed. Hg2+andp‐hydroxymercuribenzoate inhibited the enzyme activity at very low concentrations. One sulfhydryl group was found per molecul

ISSN:0233-111X    

DOI:10.1002/jobm.3620270807

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

摘要:

AbstractThe influence of the herbicide Gramoxone and its active ingredient paraquat on growth and respiratory activity ofAzotobacter vinelandiiwas studied. The experiments were performed in nitrogen‐free medium and in medium with combined nitrogen. Addition of Gramoxone (50 ppm) or paraquat (15 ppm) to the cultures during lag phase caused a total inhibition of growth. However, even after 24 h of incubation in the presence of herbicides the number of viable counts did not decrease. When herbicides were added to exponentially growing cultures, the growth response of the cultures was different. After addition of herbicides only a transient short inhibition period was noted and the length of the inhibition period was dependent on the time of herbicide addition. Neither Gramoxone (50 ppm) nor paraquat (15 ppm) enhanced catalase production. The respiratory activity of paraquat‐treated cells in the presence of 1 mM KCN was distinctly reduced (75%), while that of untreated cells did not cha

ISSN:0233-111X    

DOI:10.1002/jobm.3620270808

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

摘要:

AbstractTo investigate the induction of phenol hydroxylase and catechol 1,2‐dioxygenase inCandida maltosaL4 during chemostat cultivation, changes in the growth‐limiting substrate were carried out at different dilution rates.No activity of phenol hydroxylase and catechol 1,2‐dioxygenase could be detected in the cells during chemostat cultivation ofC. maltosaL4 under glucose limitation independent of the dilution rate. However, once the feed line was changed from glucose medium (sr= 28 mM) to a medium containing either phenol (sr= 28 mM) or a mixture of phenol (sr= 18 mM) and glucose (sr= 10 mM), both the phenol hydroxylase and the catechol 1,2‐dioxygenase were fully induced. After 5 hours at all dilution rates tested (D= 0.05 h−1,D= 0.11 h−1, andD= 0.2 h−1). In spite of this enzyme synthesis, the cells were washed out ifC. maltosaL4 was shifted from glucose to phenol at a higher dilution rate thanD= 0.05 h−1, probably due to accumulation of inhibiting concentrations of phenol in the medium and starvation of NADPH. If being shifted from glucose to a mixture of phenol and glucose, however, the cells reached a new steady state even at a higher dilution rate ofD= 0.2 h−1.The specific activity of phenol hydroxylase in crude extracts ofC. maltosaL4 was nearly independent of the growth rate in the rangeD= 0.05 h−1toD= 0.2 h−1on both phenol and a mixture of phenol and glucose, respectively, as the growth‐limiting substrates. In contrast, catechol 1,2‐dioxygenase activity correlated with the growth rate when the cells were cultivated on phenol. In the presence of mixtures of phenol and glucose, the observed decrease of specific activity of this enzyme at a high dilution rate (D= 0.2 h−1) is possibly a result of repression by gluco

ISSN:0233-111X    

DOI:10.1002/jobm.3620270809

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

ISSN:0233-111X    

DOI:10.1002/jobm.3620270811

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

摘要:

AbstractA plasmid‐cloning system was developed forStreptomyces viridochromogenesTü494, a producer of the tripeptide antibiotic phosphinothricyl‐alanyl‐alanine (PTT). Parameters affecting protoplast formation and transformability ofS. viridochromogeneswere investigated in detail. A procedure giving rise to transformation efficiencies of 104–105transformants per μg DNA was worked out. SeveralStreptomycesplasmid vectors such as pIJ350, pIJ61, pEB2, pGM4 and pSW2 were tested inS. viridochromogenes.Some of these vectors (pGM4, pEB2) showed a high copy number, whereas the copy number of others (pIJ350, pIJ61 and pSW2) was markedly lower. Under non‐selective conditions some of the vectors (pIJ350, pEB2) were not stably maintained, in contrast to the vectors pGM4 and pSW2 which did not require any selection pressure for stable meintanance. Therefore, the plasmid vectors pGM4 and pSW2 derived from endogenous replicons ofStreptomyces ghanaensisstrains represent appropriate plasmid vehicles for cloning experiments inS. virido

ISSN:0233-111X    

DOI:10.1002/jobm.3620270812

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY

ISSN:0233-111X    

DOI:10.1002/jobm.3620270814

出版商:Wiley‐VCH    

年代:1987

数据来源: WILEY