A simple procedure for the preparation of α_s2-casein is presented and the experiments with this fraction and plasminogen suggested that plasminogen activator (PA) activity may be involved in the α_s2-casein fraction. For the preparation of α_s2-casein, acid-precipitated whole casein treated previously with 2-mercaptoethanol was fractionated in 50% ethanol by the addition of ammonium acetate (50 mM at final concentration) at pH 7.2. The precipitate recovered by centrifugation was fractionated again as above and the resultant precipitate was dissolved in deionized water with NaOH, dialyzed against deionized water and freeze dried. For the determination of proteinase activity, dimethylcasein was incubated with casein fractions at 37℃ for various time intervals in the presence or absence of plasminogen, and the increase in absorbance at 420 nm was measured after the reaction with trinitrobenzensulfonic acid (TNBS). PA activity was estimated by subtracting proteinase activity in the absence of plasminogen (plasmin activity) from that in its presence. PA activity in α_s2-casein fraction was also observed by urea-polyacrylamide gel electrophoresis (urea-PAGE). The results of urea-PAGE of this fraction heated at various temperature indicated that the PA activity was relatively heat stable. PA activity in the α_s2-casein fraction was 2.5 times higher than that in unfractionated acid casein.

抄録全体を表示

 The milk, collected from a ginkgo-toothed beaked whale (Mesoplodon ginkgodens) which was stranded at the beach of Chitou Bay, Baisha village, Penghu County, Taiwan on 30 December, 2002, was analyzed. The milk consists of 66.5% of water, 14.6% of fat, 17.6% of protein, 0.1% of carbohydrate and 1.2% of ash. Fat content is less than that in the Stejneger's beaked whale and those in other whales, whereas protein content is higher. As to minerals, calcium, sodium, potassium, iron, magnesium and zinc were analyzed. Contents of sodium, potassium, magnesium and zinc are higher than those of Stejneger's beaked whale. Among fatty acids composition, oleic acid content was highest and accounted for about 50% of all fatty acids detected. Amino acid composition was similar to that of the minke whale, and glutamic acid and leucine contents were high.

抄録全体を表示

 短期大学生（食物健康分野），看護短期大学生，栄養士，幼稚園・保育園の教諭と保護者の5グループに属する474名の女性を対象として，カルシウム・鉄が添加された牛乳に対する認識についてアンケート調査を行い，Χ² 分析により解析した。“鉄”から連想されるイメージには，「血液」，「貧血」があげられ，グループ間における有意差は認められなかった。一方，“カルシウム”から連想されるイメージでは，栄養士を除く全てのグループで最も多く「骨形成」があげられていたのに対し，栄養士では「骨粗鬆症」をあげた割合が最も高かった。いずれのグループでも，牛乳中に含まれるカルシウム，鉄量を実際に含まれている量より多いと，過大評価していた。栄養士の88.1%と保護者の71.0%がカルシウム・鉄添加牛乳が市販されていることを知っており，また，栄養士の54.8%と保護者の51.8%がそれらの牛乳を飲んだことがあると答えた。しかしながら，カルシウム・鉄添加牛乳に対する彼らの意見は多くが否定的であり，特に栄養士（55.6%）は他のグループのなかでも最も，栄養素添加に対して否定的な意見の割合が高かった。その主な理由として，栄養素を強化された食品より，食品本来の栄養素を摂るべきであると考えていることがあげられていた。

抄録全体を表示