摘要:

AbstractA blue‐green strain showing loss of phycoeryhtrin pigment was obtained from the 15 mM fructose and 10−5M DCMU [3‐(3,4‐dichlorophenyl),1,1‐dimethyl urea] supplemented photoheterotrophic culture of the blackish‐brown rice‐field cyanobacteriumNostoc linckia.Absence of phycoerythrin in the mutant strain was ascertained from the whole cell absorption spectra and spectra of water soluble pigments. Quantitative estimation of photosynthetic pigments of the parent and mutant strain showed that increase in the chlorophyll and phycocyanin content took place in the mutant with a total loss of phycoerythrin. Subculturing under low and high light intensities brought no change in the mutant. The mutant strain grew well, synthesized high amounts of chlorophyll and phycocyanin and possessed higher nitrogen‐fixing capacity in comparison to the

ISSN:0233-111X    

DOI:10.1002/jobm.3620350202

出版商:Wiley‐VCH    

年代:1995

数据来源: WILEY

ISSN:0233-111X    

DOI:10.1002/jobm.3620350203

出版商:Wiley‐VCH    

年代:1995

数据来源: WILEY

摘要:

AbstractBacterial populations associated with poultry processing were determined on neck skin samples, equipment surfaces and environmental samples by replicate surveys. Aerobic plate counts, Enterobacteriaceae counts andPseudomonascounts were performed by standard procedures and the prevalence ofListeria, presumptiveSalmonellaandStaphylococcus aureusdetermined. Statistically significant (P<0.05) increases in counts of all types of bacteria were obtained on product samples as a result of processing. Although bacterial counts on neck skin samples decreased by 0.3 to 0.4 log CFU g−1after spray washing of carcasses, subsequent spinchilling and packaging of whole carcasses resulted in 0.7 to 1.2 log CFU g−1increases. Bacterial numbers on equipment surfaces, however, decreased significantly from the „dirty”︁ to the „clean”︁ areas of the abattoir. Transport cages, „rubber fingers”︁, defeathering curtains, shackles and conveyor belts repeatedly showed aerobic plate counts in excess of 5.0 log CFU 25 cm−2. Aerobic plate counts of scald tank and spinchiller water were 2 log CFU ml−1higher than those of potable water samples. Bacterial numbers of the air in the „dirty”︁ area were higher than those of the „clean”︁ area.Listeria, presumptiveSalmonellaandStaphylococcus aureuswere isolated from 27.6, 51.7 and 24.1% of all product samples, respectively, andListeriaandStaphylococcus aureuswere also isol

ISSN:0233-111X    

DOI:10.1002/jobm.3620350204

出版商:Wiley‐VCH    

年代:1995

数据来源: WILEY

摘要:

AbstractFrom an aquifier contaminated with phenolic compounds seven bacterial strains able to grow on phenol and several mono‐ and disubstituted alkylphenols as sole source of carbon and energy were isolated. Five isolates belong to the genusPseudomonas, two to the genusBacillus.The isolate most active in utilization of the applied xenobiotics was identified asBacillus pumilusand used for the investigation of the degradation pathways in liquid cultures. Cells of this strain precultured on phenol were able to utilizepara‐cresol as sole carbon source via the oxidation of the methylsubstituent and intradiol ring cleavage of the resulting protocatechuic acid, whereas an intradiol ring fission of the intermediate 4‐methylcatechol led to 4‐methylmuconolactone as dead end‐product. Cells precultured onmeta‐ andortho‐cresol were able to utilize the respective compounds as sole carbon sources via 3‐methylcatechol, which induced the following extradiol ring fission pathway. Cells precultured on phenol were able to cooxidizemeta‐ as well asortho‐cresol to 3‐methylcatechol, which was cleaved via an intradiol ring fission, finally leading to the dead end‐produc

ISSN:0233-111X    

DOI:10.1002/jobm.3620350205

出版商:Wiley‐VCH    

年代:1995

数据来源: WILEY

摘要:

AbstractOne hundred and eleven identified and seven unidentified species in addition to 5 varieties belonging to forty‐three aquatic fungal genera were recovered from 452 soil samples collected randomly from different localities in Nile Delta and Suez canal regions including eleven governorates. The investigated soil samples were collected seasonally during the period from autumn 1990 to summer 1991 (113 samples each season). The richest season (85 identified and 5 unidentified species in addition to 2 varieties) in aquatic fungi was the winter season (10.0‐15.5°C) whereas the poorest (32 identified and 5 unidentified species in addition to one variety) was summer (24.0‐27.5°C). The richest soil samples in aquatic fungi were those of low or moderate temperature seasons, high contents of organic matter and considerably poor in total soluble salts. The pH value did not show any regular seasonal variation and did not exhibit any considerable influence on fungal populations. Some aquatic fungal genera and species were disappeared completely in certain seasons and vice versa.The most dominant aquatic fungal genera werePythium, Allomyces, AqualinderellaandNowa‐kowskiella.The commonest aquatic fungal species wereAllomyces anomalus, Aqualinderella fermentans, Nowakowskiella elegans, Blastocladiopsis parvaandDictyuchus

ISSN:0233-111X    

DOI:10.1002/jobm.3620350206

出版商:Wiley‐VCH    

年代:1995

数据来源: WILEY

摘要:

AbstractSodium chloride stress results in an increased lag phase ofRhizobiumculture at inhibitory concentrations without affecting either the mean generation time (MGT) or the duration of log period. Irrespective of the phase of addition of NaCl the cells exhibited a ‘critical’ phase. Osmoprotectants do decrease the period of ‘critical’ phase but only if added prior to or along with the addition of NaCl. There is a progressive decrease in the protein content of cells grown under NaCl stress and betaine has no effect on the protein

ISSN:0233-111X    

DOI:10.1002/jobm.3620350207

出版商:Wiley‐VCH    

年代:1995

数据来源: WILEY

摘要:

AbstractWhole cells ofBacillus megateriumB6were immobilized by ionotropic, thermal gelation and polymerization of which ionotropic gelation was found to be most suitable process for α‐amylase production. Strontium was proved to be the best divalent cation for alginate entrapment of cell in terms of enzyme production and reusability of the cel

ISSN:0233-111X    

DOI:10.1002/jobm.3620350208

出版商:Wiley‐VCH    

年代:1995

数据来源: WILEY

摘要:

AbstractCrude glucoamylase preparation fromRhizoctonia solaniwas used to saccharify raw and cooked starch. Various concentrations of potato starch and wheat flour from 10–40%, w/v were used for mashing but 30% was found to be the optimal and economical. The saccharified mash yielded 5.89%, v/v ethanol in a simultaneous saccharification and fermentation process using a yeast strainSaccharomyces cerevisae(SC‐39) at 35°C for 4 days. Removal of inhibitory substances from the fermenting broth through dialysis caused considerable increase in ethanol produc

ISSN:0233-111X    

DOI:10.1002/jobm.3620350209

出版商:Wiley‐VCH    

年代:1995

数据来源: WILEY

ISSN:0233-111X    

DOI:10.1002/jobm.3620350210

出版商:Wiley‐VCH    

年代:1995

数据来源: WILEY

摘要:

AbstractCultivation ofZoophthora (Erynia) neoaphidis, in comparison with other species ofZoophthoragenus, requires more complex nitrogen source. The best mycelium growth was obtained when 8 day old mycelium was used as an inoculum for liquid culture. On the basis of Gas Chromatography/Mass Spectrometry (GC/MS) methods, the structures of the neutral lipids produced by this fungus species, were determined. Decanoic acid was the most characteristic component (over 45%). The level of hexadecanoic and octadecanoic acid was relatively lower, although their contribution as „bonded”︁ acid in diacylglyceride (DG) and triacylglyceride (TG) fractions, was significant. Contrary toZoophthora (Erynia) ovispora, the presence of campesterol and/or dihydrobrassicosterol was p

ISSN:0233-111X    

DOI:10.1002/jobm.3620350211

出版商:Wiley‐VCH    

年代:1995

数据来源: WILEY