Availability of 5-bromo-4-chloro 3-indoly-β-D-garactopyranoside-MUG (X-GAL-MUG) for total coliform bacteria and Escherichia coli has been evaluated in comparison with o-nitrophenyl-β-D-garactopyranoside-4-methyl-umbelliferyl-β-D-glucuronide (MMO-MUG) method and traditional lactose fermentation method. With 200 drinking well water samples, we obtained the coincidence of in the 90% of results obtained by X-GAL-MUG and MMO-MUG method, and also 93% by X-GAL-MUG and traditional lactose fermentation method. these seen to indicate the usefulness of X-GAL-MUG method for the detection of total coliform bacteria and E. coli in drinking well water.

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Fluorocult laurylsulfate X-GAL broth (LMX) containing a chromogenic substrate, 5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside (X-GAL), for detection of coliforms and a fluorogenic one, 4-metylumbelliferyl-β-D-glucuronide, for detection of Escherichia coli was used for enumeration of these microorganisms in environmental specimens and the medium was compared with a conventional medium, BGLB, and another chromogenic medium, Colilert.
The most probable numbers (MPN) of total coliforms, fecal coliforms and fecal E. coli obtained with LMX and BGLB showed a good correlation, but that of total E. coli obtained with LMX was higher than that with BGLB, so the former medium was more sensitive than the latter in detection of E. coli. LMX can simultaneously detect coliforms and E. coli, but the detection of E. coli with BGLB required 5 to 6 days because of the necessity of the confirming tests. Moreover, in comparing LMX and Colilert, MPN of total coliforms and total E. coli were correlated. With some samples, the color of X-GAL in LMX changed more slowly than 2-nitrophenyl-β-D-galactopyranoside in Colilert, and it seemed that the use of a water bath is preferable for incubation of LMX.
Therefore, LMX may be useful and convenient for detection and enumeration of coliforms and E. coli.

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According to the introduction of the consumable period to commercial foods, temporal changes in a Japanese-style undried confectionary were examined microbiologically and chemically during storage. “Nerikiri” was choosen as a model. At the initial period bacteria was the most predominant in number among the microorganisms contaminating the sample, followed by yeasts, coliforms, and molds. At the higher temperature between 10-30°C, growths of bacteria, molds, and yeasts were more accelerated during storage. In contrast, coliforms decreased in number at 30°C with time. Fungal colonies of were observed to grow on the surface of the sample at 20 and 30°C. During storage pH of the sample was decreased, whereas the water activity did not change. No considerable differences in microbial growth between factories were observed. Also, no remarkable differences in microbial growth among the seasons when the samples were produced were seen except one case. These results suggested that the consumable period of “nerikiri” could be 2 and 3 days in summer and other seasons, respectively.

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Yellow spots occurred on the surface of sliced ham, which was made without sodium nitrite and stored at 4°C for 2 to 3 weeks. Abundunt lactococci and lactobacilli were predominantly isolated from those spots.
Fresh sliced ham without the preservative was spotted with these 127 coccus and 74 bacillus strains, and then incubated at 4°C or 20°C. The yellow spots were reproduced on the ham by 34 lactococci, suggesting that these lactoc6cci were closely associated with the yellow spots on the ham.
The 34 yellow spot reproducing lactococci and 11 nonreproducing lactococci were all Leuconostoc sp., Which grew at 4°C, but not at 30°C. These strains were subdivided into three groups, i.e., Lemonostoc groups A, B and C.
The phenotypical characteristics of Leuconostoc guorp B to fermentize carbohydrates was identical to that of Lemconostoc pseudomesenteroides JCM 9696^T. This group included 28 yellow spot reproducing strains and 2 nonreproducing strains. Leuconstoc group A fermentized amygdalin, and included 6 reproducing strains and l nonreproducing strains. Leuconostoc group C fermentized amygdalin but not mannitol, and included 1 reproducing and 8 nonreproducing strains.

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