STATUS OF THE RADAPPERTIZATION OF MEATS1

1974 ◽  
Vol 37 (2) ◽  
pp. 86-93 ◽  
Author(s):  
D. B. Rowley ◽  
Abe Anellis ◽  
E. Wierbicki ◽  
A. W. Baker
Keyword(s):  
Sodium Chloride ◽  
Low Temperature ◽  
Proteolytic Enzymes ◽  
Model Systems ◽  
Human Consumption ◽  
Cured Meats ◽  
Radiation Resistant ◽  
Animal Feeding ◽  
Resistant Strains ◽  
Microbiological Data

Considerable progress has been made toward development of highly acceptable radappertized meats through application of a heat treatment to an internal temperature of 65–80 C to inactivate proteolytic enzymes before irradiation, low temperature (−30 ± 10 C) of the food during irradiation, and addition of low levels of tripolyphosphate and sodium chloride. To assure that radappertized meats are free of potential pathogens and spoilage microorganisms they are given a minimum radiation dose (MRD) computed to effect a 12 log cycle reduction in the most radiation resistant strains of Clostridium botulinum spores. Inoculated pack studies are carried out to obtain the specific microbiological data required for computing the MRD. Cured meats normally have a lower MRD than uncured meats. In model systems concentrations of sodium chloride (NaCl) up to 4.0% (w/v) present during irradiation had no effect on radiation resistance, but NaCl did inhibit recovery of irradiated spores. A mixture of salts (4.0% NaCl, 30 ppm NaNO2 500 ppm NaNO3) had essentially the same effect as NaCl alone. Of 11 genera of vegetative cells examined, Micrococcs radiodurans and Streptococcus faecium were shown to be the most resistant to low-temperature gamma irradiation. Before the radappertization process can be established commercially it is necessary to provide proof that products so treated are safe for human consumption. An intensive animal feeding study of radappertized (4.7–7.1 Mrads) beef was initiated in 1971 and is expected to be completed in 1976.

Effect of Food Environment on Staphylococcal Enterotoxin Synthesis: A Review

1983 ◽  
Vol 46 (6) ◽  
pp. 545-555 ◽  
Author(s):  
J. L. SMITH ◽  
R. L. BUCHANAN ◽  
S. A. PALUMBO
Keyword(s):  
Staphylococcus Aureus ◽  
Sodium Chloride ◽  
Carbon Source ◽  
Environmental Factors ◽  
Food Environment ◽  
Inoculum Size ◽  
Model Systems ◽  
Sublethal Stress ◽  
Effect Of Food ◽  
Chloride Water

Effects of various nutritional and environmental factors on growth and enterotoxin synthesis by Staphylococcus aureus in model systems and foods are reviewed. Factors discussed include effects of inoculum size, competing microflora, gaseous atmosphere, carbon source, temperature, pH, sodium chloride, water activity, mineral ions and sublethal stress. Areas where additional research is needed are also discussed.

scholarly journals CONSTRUCTION, EXPRESSION AND PURIFICATION OF RECOMBINANT PRE-MATURE PEPTIDE OF PLANTARICIN F FROM Lactobacillus plantarum S34 IN Escherichia coli

2015 ◽  
Vol 16 (1) ◽  
pp. 31
Author(s):  
Kusdianawati Kusdianawati ◽  
Apon Zaenal Mustopa ◽  
Suharsono Suharsono ◽  
Bugi Ratno Budiarto ◽  
Fatimah Fatimah ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Lactobacillus Plantarum ◽  
Proteolytic Enzymes ◽  
Leader Peptide ◽  
Human Consumption ◽  
Mature Peptide ◽  
Expression And Purification ◽  
Food Preservative ◽  
E Coli ◽  
Sds Page

Plantaricin is one of bacteriocins that have the potential to be used as food preservative. Plantaricin is safe for human consumption because it can be easily degraded by proteolytic enzymes. The objective of this study was to express and purify recombinant pre-mature peptide of plantaricin F from <em>Lactobacillus plantarum</em> S34 in <em>Escherichia coli</em>. Plantaricin gene-specific primer was used to obtain pln F structural gene amplicon from L. <em>plantarum</em> S34. This amplicon was cloned in pET32a vector and expressed in E. coli BL21 (DE3) pLysS. Pre-mature plantaricin F peptide was expressed as Histagged-fusion protein and separated by Co2+-chelating affinity chromatography. L. <em>plantarum</em> S34-derived pre-mature plantaricin F peptide fused with thioredoxin-(His)6tag had successfully been expressed in E. <em>coli</em> BL21 (DE3) pLysS using pET32a as an expression vector. The fused recombinant pln F as pre-mature state expressed had a molecular mass of +24 kDa, meanwhile the fused recombinant that contained only the leader peptide of pln F appeared as +20 kDa based on SDS-PAGE separations. The optimal production of fused recombinant pln F as soluble fraction was obtained when culture condition was added with 0.5 mM of IPTG and incubated at 22°C for 5 hours (OD~1). Furthermore, the expression of fused recombinant pln F as its pre-mature peptide pointed out that the pln F’s leader peptide could be proteolytically cleaved by a system in heterologous cells. Overall, heterologous pln F production as pre-mature peptide fused with thioredoxin-(His)6tag had been well established. From this research, we expect plantaricin F can be expressed and purified in E. coli.

scholarly journals Survey on ergot alkaloids in cereals intended for human consumption and animal feeding

2011 ◽  
Vol 8 (12) ◽  
Author(s):  
José Diana Di Mavungu ◽  
Daria A. Larionova ◽  
Svetlana V. Malysheva ◽  
Carlos Van Peteghem ◽  
Sarah De Saeger
Keyword(s):  
Ergot Alkaloids ◽  
Human Consumption ◽  
Animal Feeding

An established cell line from mouse kidney medullary thick ascending limb. I. Cell culture techniques, morphology, and antigenic expression

1986 ◽  
Vol 251 (2) ◽  
pp. C299-C311 ◽  
Author(s):  
J. D. Valentich ◽  
M. F. Stokols
Keyword(s):  
Cell Line ◽  
Proteolytic Enzymes ◽  
Mouse Kidney ◽  
Transport Processes ◽  
Model Systems ◽  
Established Cell Line ◽  
Epithelial Cell Line ◽  
Thick Ascending Limb ◽  
Culture Techniques ◽  
Medullary Thick Ascending Limb

The effective use of cultured cells as model systems for investigating the differentiation and regulation of transport processes in renal tubular epithelial cells depends on the availability of functional long-term cell lines derived from specific nephron segments. Conventional culture procedures that treat cells as proliferating microorganisms possess several inherent limitations that could contribute to phenotypic instability and limited proliferative capacity in vitro. In this study, culture techniques were adopted that avoid exposure of cells to proteolytic enzymes, maintain intercellular contacts, and allow cells to remain continually adherent to a collagen gel substratum. This methodology resulted in the development of a continuous epithelial cell line from identified, microdissected segments of the mouse kidney medullary thick ascending limb.

scholarly journals The binding of hydrogen ions to an acidic glycoprotein from bovine cortical bone

1967 ◽  
Vol 105 (3) ◽  
pp. 1171-1175 ◽  
Author(s):  
A. R. Peacocke ◽  
P A Williams
Keyword(s):  
Sodium Chloride ◽  
Glutamic Acid ◽  
Titration Curve ◽  
Analytical Data ◽  
Total Content ◽  
Bone Sialoprotein ◽  
Model Systems ◽  
Carboxyl Groups ◽  
Hydrogen Ions ◽  
Titration Curves

The H+ ion dissociation of bone sialoprotein in 0·2m-sodium chloride at 25° was studied. The total content of carboxyl groups available for titration was calculated by comparing the titration curve with the titration curves of three model systems and by the use of analytical data. This comparison showed that 7·0 carboxyl groups/mol. do not participate in the titration, and it is proposed that these are aspartic acid or glutamic acid carboxyl groups present as amides; this is also indicated by titration of the sialoprotein after acid hydrolysis. The titration of carboxyl groups was found to agree well with the Linderstrøm-Lang equation for spherical macroions.

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