Development and application of a bioassay to study the effects of nutrients, pH, and active substances on Sordaria macrospora fruiting

1986 ◽  
Vol 32 (12) ◽  
pp. 930-936 ◽  
Author(s):  
Myriam Roure ◽  
Marie-Louise Bouillant
Keyword(s):  
Agaricus Bisporus ◽  
Culture Medium ◽  
Small Variation ◽  
Fruiting Bodies ◽  
Sordaria Macrospora ◽  
Isolation And Characterization ◽  
Initial Ph ◽  
Active Substances

The perithecial development of Sordaria macrospora (Auersw.) is prevented by ammonium salts as nitrogen source, but only below a critical initial pH in the culture medium. Around this point, a very small variation in the initial pH can induce a morpho-genetic change. Within the inhibition range, supplementation of the culture medium with aqueous cell-free extracts from the fruiting mycelia or fruiting bodies of some fungi overcomes the ammonium inhibition. This phenomenon was used to develop a biological test which could be used to isolate, for the determination of their chemical structure, active fungal substances. The precise physiological conditions required to obtain good reproducibility and reliability with this bioassay have been established, which allows the important effects of nutrients and pH on S. macrospora fruiting to be determined. An application is described with the isolation and characterization of hercynine, an active substance purified from Agaricus bisporus fruiting bodies. Its activity is compared with that of other basic substances.

scholarly journals Isolation and characterization of pathogenic Escherichia coli bacteriophages from chicken and beef offal

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Celosia Lukman ◽  
Christopher Yonathan ◽  
Stella Magdalena ◽  
Diana Elizabeth Waturangi
Keyword(s):  
Escherichia Coli ◽  
Foodborne Pathogens ◽  
High Efficiency ◽  
Multiplicity Of Infection ◽  
Isolation And Characterization ◽  
Transmission Electron ◽  
Pathogenic Escherichia Coli ◽  
Family Based

Abstract Objective This study was conducted to isolate and characterize lytic bacteriophages for pathogenic Escherichia coli from chicken and beef offal, and analyze their capability as biocontrol for several foodborne pathogens. Methods done in this research are bacteriophage isolation, purification, titer determination, application, determination of host range and minimum multiplicity of infection (miMOI), and bacteriophage morphology. Results Six bacteriophages successfully isolated from chicken and beef offal using EPEC and EHEC as host strain. Bacteriophage titers observed between 109 and 1010 PFU mL−1. CS EPEC and BL EHEC bacteriophage showed high efficiency in reduction of EPEC or EHEC contamination in meat about 99.20% and 99.04%. The lowest miMOI was 0.01 showed by CS EPEC bacteriophage. CI EPEC and BL EPEC bacteriophage suspected as Myoviridae family based on its micrograph from Transmission Electron Microscopy (TEM). Refers to their activity, bacteriophages isolated in this study have a great potential to be used as biocontrol against several foodborne pathogens.

Isolation and characterization of the ethynylestradiol-biodegrading microorganism Fusarium proliferatum strain HNS-1

2002 ◽  
Vol 45 (12) ◽  
pp. 175-179 ◽  
Author(s):  
J.H. Shi ◽  
Y. Suzuki ◽  
B.-D. Lee ◽  
S. Nakai ◽  
M. Hosomi
Keyword(s):  
Culture Medium ◽  
Polar Compounds ◽  
Sole Source ◽  
Order Rate Constant ◽  
Fusarium Proliferatum ◽  
Rrna Gene ◽  
28S Rrna ◽  
Isolation And Characterization ◽  
Phenolic Group

We cultivated hundreds of sediment, soil, and manure samples taken from rivers and farms in a medium containing ethynylestradiol (EE2) as the sole source of carbon, so that microorganisms in the samples would acclimatize to the presence of EE2. Finally, we isolated an EE2-degrading microorganism, designated as strain HNS-1, from a cowshed sample. Based on its partial nucleotide sequence (563 bp) of the 28S rRNA gene, strain HNS-1 was identified as Fusarium proliferatum. Over 15 days, F. proliferatum strain HNS-1 removed 97% of EE2 at an initial concentration of 25 mg.L−1, with a first-order rate constant of 0.6 d−1. Unknown products of EE2 degradation, which may be more polar compounds that have a phenolic group, remained in the culture medium.

Isolation and Characterization of a Chlorogenic Acid Esterase from Aspergillus niger

1980 ◽  
Vol 35 (3-4) ◽  
pp. 209-212 ◽  
Author(s):  
B. Schöbel ◽  
W. Pollmann
Keyword(s):  
Enzyme Activity ◽  
Chlorogenic Acid ◽  
Divalent Cations ◽  
Hydrolysis Product ◽  
The Other ◽  
Temperature Optimum ◽  
Pig Liver ◽  
Isolation And Characterization

Abstract The isolation and characterization of a specific chlorogenic acid esterase is described. The enzyme activity is measured by determination of the hydrolysis product caffeic acid. The enzyme had been concentrated by means of ultrafiltration and column-chromatography. The pH- and temperature optimum were 6.5 and 45 °C respectively. Divalent cations were not required for the enzyme activity. As other esterases, this enzyme is inhibited by di-isopropyl-phosphorofluoridate. The Km-value is 0.70 mᴍ chlorogenic acid, the molecular weight 240000. The described enzyme is specific for chlorogenic acid. On the other hand a typical unspecific esterase like the pig liver esterases does not split chloro­genic acid. The isoelectric focusing reveals several isoenzymes of chlorogenase within a pI-range of 4.0-4.5.

scholarly journals The Blocked Amino-Terminal Peptide of Feather Keratin

1971 ◽  
Vol 24 (1) ◽  
pp. 179 ◽  
Author(s):  
IJ O'donnell
Keyword(s):  
Molecular Weight ◽  
Acetic Acid ◽  
Amino Groups ◽  
Amino Terminal ◽  
Acetyl Content ◽  
Electrophoretic Patterns ◽  
Isolation And Characterization ◽  
Primary Amino

Proteins extracted from reduced and carboxymethylated feather keratins (SCM-keratins) have been studied by Harrap and Woods (1964a, 1964b, 1967). They have demonstrated the presence of electrophoretic heterogeneity amongst the proteins and have obtained a molecular weight of approximately 11,000 in agreement with earlier work of Woodin (1954). There was no indication of marked heterogeneity with respect to size. Using acid hydrolysis and determination of acetic acid produced they found an acetyl content of 1 �30 molesj104 g in the rachis off owl feathers. These were thought to be attached to primary amino groups since there were no O-acetyl groups. In the present paper the isolation and characterization of the predominant, and probably sole, amino-terminal tripeptide from goose feather calamus is described. Goose feather calamus was chosen because its extracted proteins had one of the simplest electrophoretic patterns of proteins from the feathers of a number of species (Harrap and Woods 1967).

Isolation and characterization of bacterial diversity from soils supplemented with electrical transformer fluids

2011 ◽  
Vol 1 (2) ◽  
pp. 107-113
Author(s):  
Nwinyi Obinna C ◽  
Alade Adetutu ◽  
Leo‐ Akpan Imaobong R ◽  
Oladele Bolaji.O
Keyword(s):  
Optical Density ◽  
Culture Medium ◽  
Agricultural Land ◽  
Agricultural Soils ◽  
Bacterial Species ◽  
Minimal Salt Medium ◽  
Isolation And Characterization ◽  
The Mean ◽  
Biomass Increase

Repetitive enrichment of soils samples from an agricultural land and newly marked dumpsite on electrical transformer fluid yielded six bacterial species that have the capacity to utilize electrical transformer fluids (askarel) as carbon and energy source. Bacterial species namely: Micrococcus, Arthrobacter, Pseudomonas putida, Pseudomonas spp, Norcadia and Corynebacterium were identified using morphological and biochemical characteristics. The abilities of these bacterial species to utilize the electrical transformer fluids as carbon source in minimal salt medium (MSM); sub cultured in concentrations of 5, 10, 15 and 20μL of electrical transformer fluids were investigated for twenty‐one days period. Physiological changes in terms of biomass increase were monitored by measuring the pH and optical density of the culture medium. From the results obtained, there was observed a general decrease in the pH and  increase in Optical density (O.D). The mean pH and O.D. readings ranged between (4.34‐6.13 and 0.073‐0.386) respectively. The decreased pH could justify for the acidic metabolites produced in the course of utilization of askarel as growth substrates. This study suggested that, the tropical ecosystems can provide exotic bacterial species that are capable of degrading or mineralizing polychlorinated biphenyls and their derivatives from dumpsites and agricultural soils.

scholarly journals Production and Biochemical Characterization of a High Maltotetraose (G4) Producing Amylase fromPseudomonas stutzeriAS22

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Hana Maalej ◽  
Hanen Ben Ayed ◽  
Olfa Ghorbel-Bellaaj ◽  
Moncef Nasri ◽  
Noomen Hmidet
Keyword(s):  
Culture Medium ◽  
Biochemical Characterization ◽  
Amylase Activity ◽  
Potato Starch ◽  
Pseudomonas Stutzeri ◽  
Crude Enzyme Preparation ◽  
Amylase Production ◽  
Initial Ph ◽  
Very High

Amylase production and biochemical characterization of the crude enzyme preparation fromPseudomonas stutzeriAS22 were evaluated. The highestα-amylase production was achieved after 24 hours of incubation in a culture medium containing 10 g/L potato starch and 5 g/L yeast extract, with initial pH 8.0 at 30°C under continuous agitation at 200 rpm. The optimum temperature and pH for the crudeα-amylase activity were 60°C and 8.0, respectively. The effect of different salts was evaluated and it was found that bothα-amylase production and activity were Ca2+-dependent. The amylolytic preparation was found to catalyze exceptionally the formation of very high levels of maltotetraose from starch (98%, w/w) in the complete absence of glucose since the initial stages of starch hydrolysis (15 min) and hence would have a potential application in the manufacturing of maltotetraose syrups.

In situ determination of kinetic parameters for biofilms: Isolation and characterization of oligotrophic biofilms

1986 ◽  
Vol 28 (11) ◽  
pp. 1753-1760 ◽  
Author(s):  
Bruce E. Rittmann ◽  
LouAnn Crawford ◽  
Cynthia K. Tuck ◽  
Eun Namkung
Keyword(s):  
Kinetic Parameters ◽  
Isolation And Characterization
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