Destruction of Enteric Bacteria in Liquid Egg with β-Propiolactone

Liquid whole egg or egg white, inoculated with Escherichia coli 1485, Salmonella senftenberg ATCC 8400, or Salmonella typhimurium 84-I, was treated with concentrations of β-propiolactone ranging from 0.05 to 0.3%. Egg white containing 1 × 10 3 to 1 × 10 6 cells of E. coli 1485 per ml was sterilized in 1 hr at 27 C by lactone concentrations of 0.2 and 0.3%. Egg white containing 1 × 10 5 cells of S. senftenberg ATCC 8400 per ml was sterilized in 12 hr at 10 C by 0.1% lactone and in 2 to 3 hr by 0.3% lactone at the same temperature.

Liquid whole egg inoculated with 1 × 10 5 cells of either species of Salmonella was sterilized in 4 to 5 hr at 10 C with 0.2% lactone or in 2 to 3 hr by 0.3% lactone at this temperature. A mild heat treatment of either 15 min at 37 C or 1 min at 55 C markedly shortened the exposure times required for sterilization by β-propiolactone at 10 C.

After disinfection was complete, the lactone-treated liquid whole egg was reinoculated with low cell numbers of either species of Salmonella to determine the presence of residual lactone or toxic products. Liquid whole egg treated with 0.2% lactone would support the growth of salmonellae after 13 to 14 hr at 10 C. A heat treatment of 45 min at 37 C or 10 min at 55 C immediately after addition of 0.2% lactone allowed growth of the salmonellae in the lactone-treated liquid whole egg. No evidence of residual toxicity from the lactone treatment was found.

The amount of lactone needed to prevent the outgrowth of low cell numbers of either strain of Salmonella in liquid whole egg was quantitated. Liquid whole egg containing 0.06 to 0.07% lactone would not support salmonellae growth from inocula of 1 to 10 cells per ml of egg. Lactone concentrations above 0.08% prevented outgrowth of salmonellae inocula of 10 to 200 cells per ml of liquid whole egg.

An evaluation of beta-propiolactone for the sterilization of fermentation media

Twenty-five bacterial species were cultured in basal broth plus 1 of 19 different carbohydrates which were sterilized by Seitz filtration, autoclaving (112 C, 10 min), or exposure to 0.2% beta-propiolactone (BPL). No significant differences were found either in the visual observations for acid and gas, pH, or titrable acidity determinations after 3 days of incubation with any of the three preparations tested. An effort was made to further determine the effect of BPL and heat on carbohydrates by assaying for glucose before and after treatment. Results indicated that glucose was not degraded by 0.2% BPL, however, it was shown that autoclave temperatures caused extensive degradation. Statistical treatment of the results from Warburg studies indicated that BPL-treated glucose showed no appreciable toxic effects, although the actual oxygen uptake was not as great as with Seitz- or autoclave-treated glucose. The application of the BPL sterilization process was discussed.

Sterilization of Regenerated Collagen Sutures with β-Propiolactone

Data are presented to show that β-propiolactone when properly applied is a very effective agent for sterilization of regenerated collagen sutures. The chemical sterilization is accomplished with little or none of the loss in strength encountered with heat sterilization. The finished sterile suture is obtained without any harmful residue that might be detrimental to the patient.

Factors Influencing the Effect of beta-Propiolactone on Chromosomes of Vicia faba

The effect of beta-propiolactone on chromosomes is independent of pH, oxygen tension, and some metabolic inhibitors. It is influenced by temperature, concentration, and pretreatments with dinitrophenol. henol. Interphase sensitivitycalizationand localization of breaks are discussed in terms of the action of beta-propiolactone and the relationship of gamma-propiolactone to other radiomimetic compounds.

Graft Sterilization

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The use of beta-propiolactone for the preparation of virus vaccines. I. Selection of reaction conditions

The use of beta-propiolactone (BPL) for the destruction of infectivity of influenza, mumps, and poliomyelitis virus suspensions has been investigated. It was found that: (1) the infectivity was destroyed more rapidly as the pH was increased from 6 to 8, and (2) the hemagglutination titers of influenza and mumps virus suspensions were most stable to BPL treatment at pH 7. Since the pH of the medium decreases with the hydrolysis of BPL, it was found desirable to use a buffered medium for BPL treatment. Influenza and mumps vaccines prepared with BPL have been lyophilized successfully for stable storage by the addition of 5% arginine or 5% peptone prior to lyophilization. Vaccines prepared from chick allantoic fluid, which had not been frozen, required dialysis of the virus concentrate prior to BPL treatment. Reaction conditions have been selected which render the virus suspensions non infective while preserving most of the in vitro serological activity. Antigenicity tests of the virus suspensions treated with BPL are discussed in the second section (II) of this paper.

The use of beta-propiolactone for the preparation of virus vaccines. II. Antigenicity

An investigation has been made of the antigenicity of influenza virus suspensions rendered noninfective with beta-propiolactone (BPL). By treatment with BPL under various conditions, influenza vaccines could be prepared which were antigenic as indicated by production of specific antibody response in mice and guinea pigs. These vaccines were also immunizing as evidenced by their capacity to protect mice against challenge with live virus.

The carcinogenicity of beta-propiolactone for mouseskin

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