Osthoff G, de Wit M, Hugo A, Kamara B I
Department of Microbial, Biochemical and Food Biotechnology, University of the Free State, Bloemfontein, South Africa.
Comp Biochem Physiol B Biochem Mol Biol. 2007 Sep;148(1):1-5. doi: 10.1016/j.cbpb.2007.02.015. Epub 2007 Jun 19.
Data are presented that indicate the dynamic changes of nutrients in milk from three free ranging African elephant (Loxodonta africana africana) cows during lactation. At the respective collection times of 12, 14 and 18 months of lactation the nutrient content was 47.3, 52.0 and 68.6 g protein; 60.7, 87.4 and 170.8 g fat; 1.6, 2.1 0.5 g lactose and 20.9, 21.5 and 8.6 g oligosaccharides per kg milk. The protein fraction respectively consisted of 18.0, 31.7 and 45.9 g caseins/kg milk and of 29.3, 20.3 and 22.7 g whey proteins/kg milk. Electrophoresis and identification of protein bands showed that polymorphs of one whey protein may be present in elephant's milk similar to polymorphs of alpha-lactalbumin found in cow's milk. From the middle of the lactation time lactose was replaced by oligosaccharides as major carbohydrate, and the major compound of these was identified as isoglobotriose by 1H NMR spectroscopy. The lipid fraction contains a high content, of capric and lauric acids, approximately 70% of the total fatty acids, and low content of myristic, palmitic and oleic acids. During these lactation times the content of short chain fatty acids, capric and caprylic acids increased, while fatty acids lauric acid and longer decreased.
所呈现的数据表明了三头自由放养的非洲象(Loxodonta africana africana)母牛在哺乳期乳汁中营养成分的动态变化。在哺乳期分别为12、14和18个月时的采集时间点,每千克乳汁中的营养成分含量分别为:蛋白质47.3、52.0和68.6克;脂肪60.7、87.4和170.8克;乳糖1.6、2.1和0.5克;低聚糖20.9、21.5和8.6克。蛋白质部分分别由每千克乳汁中18.0、31.7和45.9克酪蛋白以及29.3、20.3和22.7克乳清蛋白组成。蛋白质条带的电泳和鉴定表明,象乳中可能存在一种乳清蛋白的多态性,类似于牛乳中发现的α-乳白蛋白的多态性。从哺乳期中期开始,乳糖被低聚糖取代成为主要碳水化合物,通过1H核磁共振光谱法鉴定这些低聚糖的主要化合物为异三聚乳糖。脂质部分中癸酸和月桂酸含量很高,约占总脂肪酸的70%,肉豆蔻酸、棕榈酸和油酸含量较低。在这些哺乳期内,短链脂肪酸癸酸和辛酸的含量增加,而月桂酸及更长链脂肪酸的含量减少。