Casein digests

The following description is from U.S. Patent 2,701,227 To 50 liters of distilled water there was added 10.17 kg of enzyme hydrolyzed casein (N-Z-Amine). The temperature was raised to 100°C and held until the casein digest solution was clear. The container was then cooled rapidly to 15°C and the cooled solution filtered through a coarse grade of filter paper. A small amount of toluene was added as a preservative and the solution... 

CULTURE MEDIUM SOYBEAN-CASEIN DIGEST DEHYDRATED 500 GRAMS 6550011561629 BT 2363 ... 

Poured, sterile soybean casein digest agar (SCDA) petri plates Poured, sterile potato dextrose agar (PDA)... 

Media-hlled vials (soybean casein digest broth or fluid thioglycollate medium) are hlled on the hlling line, transported to the freeze drier, loaded into the chamber, subjected to a simulated lyophilization process, stoppered, sealed, and incubated for 14 days at 25°C. The minimum number of vials to be used is 5000. 

Soybean casein digest broth shall be used for normal media runs but thioglycolate broth shall be used for the detection of anaerobic organisms, especially when a filtered nitrogen purge is used to ensure anaerobic conditions. 

Tryptic soya broth (soybean-casein digest medium) for normal media fill run... 

Minamiura, N., Matsumera, Y., Fukumoro, J. and Yamamoto, T. 1972. Bitter peptides in cow milk casein digests with amino acid sequence of a bitter peptide. Agr. Biol Chem. 36, 588-595. 

Figure 6.2 The chromatogram of ions at m/z 449.8 (BSA j), 653.4 (BSA2), 820.5 (BSA3), 710.4 (BSA4), 751.9 (Myoi), 692.9 (Casj) belonging to bovine serum albumin, myoglobin, and a-casein digests (5 ng each) [31].

The following ingredients were then added to the casein digest solution ... 

Hata, I., Higasiyama, S., and Otani, H. 1998. Identification of a phosphopeptide in bovine asl-casein digest as a factor influencing proliferation and immunoglobulin production in lymphocyte cultures. J. Dairy Res. 65, 569—578. 

In the membrane filtration method, the product samples are put aseptically into a volume of non-inhibitory diluent and then passed through a sterile 0.45 pm membrane filter (Fig. 1). The membrane is rinsed through with additional volumes of diluent, then aseptically cut in half. Half is transferred to a container of soybean casein digest medium (SCDM) and the other to fluid thioglycollate medium (FTM). 

Tryptic soy agar is also known as soybean casein digest agar. 

Sterility tests are normally performed by incubating the sample with fluid thioglycollate medium at 30-35° C for 14 days or with soybean-casein digest medium at 20-25° C for 14 days. The sample volume should be as large as that for human dosage. If bacterial growth is observed in either test, the preparation is considered asterile. For PET radiopharmaceuticals, these tests must be started within 24 h after the release of the product. 

Doolan and coworkers [18] used three compendial recovery conditions to construct survival curves for naturally contaminated medical devices soybean casein digest medium incubated at 20-25 C, the same incubated at 30-35 C. and fluid ihioglycollatc medium incubated at 30-35 C for 14 days. Three tests for sterility therefore constituted the basis for observing the presence of viable microorganisms in three replicate conditions making up one sample. 

Each filling trial should consist of at least 3000 items (it is normal practice to exceed the minimum to account for breakages, etc.). The medium of choice is Soybean Casein Digest Broth VSP. Where necessary, for instance in antibiotic filling processes where, no matter how effective the cleaning, residues cannot be excluded, an inactivating agent (e.g., penicillinase) should be added to the medium at an appropriate concentration. 

Frieben et al. [2] filled vials with Soybean Casein Digest Medium, sealed them, and then immersed them inverted in a suspension of 10 Escherichia coli... 

Kruse says that casein digestion may occur as follows ... 

The work of Bunjapamai, Mahoney and Fagerson (21) was the first successful attempt to separate the effects of racemization from crosslinking as measured by vitro digestion. Alkali-treatment of citraconylated (lysine-blocked) or non-blocked casein resulted in racemized only (blocked) or racemlzed and LAL cross-linked (non-blocked) casein. vitro multienzyme digestion of these preparations as well as untreated casein revealed similarly decreased digestibilities for the treated proteins whether crosslinked or not, indicating that the primary cause for reduction of casein digestibility was racemization. 

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