大腸菌および乳酸桿菌に対するシャトルベクターを構築した。シャトルベクター pJLE121は Lactobacillus casei L-49由来プラスミド pLC494 の ori と repA, pJIR418 の pMB1(ori）およびグラム陽性菌とグラム陰性菌の選択マーカーとしてのエリスロマイシン耐性遺伝子を含んでいる。pJLE121 を使用して Lactobacillus casei L-49-4（L-49株のプラスミドフリー株）への形質転換効率を調べた。その結果，1.0%グリシンを含む MRS 液体培地で培養したのち，菌体を 10 mM MgCl₂ 緩衝液で洗浄し，10%グリセリン溶液に懸濁した菌体を 1.75 kV, 200 Ω および 25 μF の条件でエレクトロポレーションを行った時に，形質転換効率が最も高かった。シャトルベクター pJLE121 は数種類の乳酸桿菌に導入され，このベクターを導入して得られた形質転換体はグラム陽性菌の選択マーカーとしてのクロラムフェニコール耐性遺伝子を含むシャトルベクター(プラスミド pLC494 の ori および repA)から得られた形質転換体よりも生育速度が早かった。

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 Numerous fermented milk products containing probiotic lactobacilli have recently been commercialized in Japan. Certain probiotic lactobacilli grow slowly in milk. Therefore, some products are produced by co-culture with ordinary yogurt starter bacteria after the addition of sufficient amounts of separately propagated viable probiotic cells.
 Only a limited culture media for the test purpose of lactobacilli are commercially available (for example MRS broth), but the media for large-scale propagation of viable cells which are able to be used as food additive are not available. The manufacture of a low -priced and preferred novel medium for lactobacilli was, therefore, attempted using cheese whey powder as a starting material. Heat labile proteins in cheese whey were removed by pre-heating, then the whey solution was complemented with casein-protease hydrolyzate, glucose, yeast extract of food additive grade, Tween 80 and minerals. The growth test was mainly performed using human originated Lactobacillus acidophilus strains. The growth of several lactobacilli in the finally attained medium (WIM broth) composed of 7% deproteinized cheese whey, 1% glucose, 0.3% yeast extract, 0.1% Tween 80 and minerals, was comparable to MRS broth. The modified WIM broth which Tween 80 was replaced with decaglycerol-monooleate and composed of only food additive grade minerals was also a prominent medium for large-scale propagation of viable cells for the purpose of adding into several food products.

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 The fluorescent filter method with “Bioplorer” (Bioplorer method), the official direct microscopic count method (Breed Method), the measurement count with “BactoScan” (BactoScan method) and the viable cell count by standard plate count method (SPC) were comparatively examined each other for the total bacterial counts (TBC) in raw milk. The coefficient of variation of Bioplorer method was better than that of Breed method. The TBC of Bioplorer method correlated well with that of Breed method. Whereas the correlations between TBC of Bioplorer method and that of BactoScan method and/or SPC were low, and the correlations between TBC of Breed method and that of BactoScan method and/or SPC were similarly low. Consequently, it was recognized that Bioplorer method was qualified for the microbes enumeration method in raw milk instead of the official direct microscopic count method (Breed method).

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 平成17年 7 月 9 日，静岡県沼津市我入道海岸付近で仔クジラとともに座礁し，死亡が確認された泌乳中のコブハクジラ（Mesoplodon densirostris）（メス）の乳腺を切開して乳汁を採取した。この乳汁を冷却（4–6℃）して(財)日本乳業技術協会（東京都千代田区九段北 1-14-19）に運び，直ちに分析に供した。
 組成は水分48.4%，脂肪34.8%，タンパク質15.8%，炭水化物0.2%，灰分0.8%であった。ミネラルとしてカルシウム，ナトリウム，カリウムの含量が高いことが認められた。アミノ酸としてグルタミン酸，ロイシン，アスパラギン酸，リジン，プロリンの含量が高かったのに対し，メチオニン，シスチン，トリプトファン，グリシンの含量が低かった。構成脂肪酸としてオレイン酸（C_18:1）の含量が高く，全構成脂肪酸の約50%を占めていた。また，ミリスチン酸（C_14:0），パルミチン酸（C_16:0），パルミトオレイン酸（C_16:1），ステアリン酸（C_18:0）ならびにアラキオレイン酸（C_20:1）の含量が高いことが認められた。

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