水牛奶乳清蛋白制备抗氧化活性肽工艺的研究

实验是以水牛奶为原料,分离纯化后得到乳清蛋白。利用碱性蛋白酶、中性蛋白酶、胰蛋白酶、木瓜蛋白酶和胃蛋白酶5种不同的蛋白酶对水牛奶乳清蛋白酶解以制备抗氧化活性多肽。酶筛选结果显示,中性蛋白酶是最适宜酶解水牛奶乳清蛋白制备抗氧化活性肽,其酶解液的还原能力和DPPH自由基清除率较其他4种酶高。探讨酶解反应时pH、温度、时间、酶浓度对酶解反应的水解度、酶解液的还原能力和DPPH自由基的清除率的影响,在单因素试验基础上,采用响应面法对酶解工艺进行优化。结果表明,中性蛋白酶酶解乳清蛋白的最佳工艺参数为:pH为7.4,温度为50.5℃,酶与底物浓度比为2.1%,酶解时间5.0h,此时2mg/mL酶解物的DPPH自由基清除率为32.58%。实测结果与预测值吻合效果良好。     

水牛乳体细胞数与理化性质关系的研究

测定麽拉水牛、尼里-拉菲水牛、高代三品种杂交水牛、一代杂交水牛乳中的体细胞数(Somatic Cell Count,SCC)及其理化性质,分析水牛乳SCC与理化性质之间的关系,探讨了水牛乳SCC水平对理化性质的影响。结果表明:在不同SCC水平下,水牛乳蛋白质、脂肪、总固形物、冰点、酒精阳性率变化不显著,水牛乳非脂固形物、乳糖、酸度、比重随着SCC的升高而显著降低,隐性乳房炎患病率随着SCC的升高而显著增加;在所测样品中,麽拉、尼里-拉菲水牛乳SCC>30×104mL-1,三品种杂交以及一代杂交水牛乳的SCC>50×104mL-1时,非脂固形物、乳糖、酸度、比重均值以及隐性乳房炎患病率变化更显著。     

基于多元统计方法进行水牛乳掺水定量鉴别

采用常规方法测定不同掺水体积比例的水牛乳掺伪样的7 个主要品质指标,并基于这些指标参数采用单因素方差分析、主成分分析和多元逐步线性回归法,对不同掺水量的水牛乳进行定量鉴别,旨在寻求一种能有效监控水牛乳掺水的快速定量鉴别方法。利用单因素方差分析不同掺伪样的7 个重要理化指标的差异性,分析结果表明,水牛乳掺水的最低检出限为7%。主成分分析中,第1主成分贡献率达到85.464%,已包含样本的大部分信息,主成分1得分与掺水量存在显著的线性关系。通过多元逐步线性回归法建立了4 个定量模型方程,其相关系数R2分别为0.965、0.982、0.986、0.989,平均绝对误差分别为－0.23%、－2.40%、0.23%、1.28%,可实现水牛乳掺水的定量鉴别。     

Characterisation and comparison of khoa prepared from camel milk with that from cow and buffalo milk

Khoa, a heat‐concentrated milk product, is used as a base material for the manufacture of many popular sweets. The comparison was made between various chemical compositions and characteristics of the khoa prepared from the camel milk with that prepared from the cow and the buffalo milk samples. The khoa prepared from the camel milk had the higher moisture, ash, acidity, soluble nitrogen, free fatty acids and peroxide value, but lower in fat, protein and lactose contents than that prepared from the cow and buffalo milk samples. There was no significant (P > 0.05) difference in 5‐hydroxymethyl furfural between khoa samples prepared from the three milks.     

摩拉×西林水牛乳化学组成变化的研究

本实验采用7头1胎的摩拉×西林水牛，分别在产犊后2h、12h、24h、36h、48h、3d、4d、5d、6d、7d、15d、30d、60d、90d、120d、150d、180d、210d采集乳样，称量产乳量，测定乳的物理性质和化学组成。结果表明：摩拉×本地水牛的泌乳高峰出现在产后第三个月（126．56kg），210d总产量805．47kg，平均日产量3．84kg：水牛产犊后2h乳的pH为6．23，乳糖2．33％，之后逐渐上升，15d之后分别在pH6．51～6．55，乳糖4．42％-4．79％之间变化；2h时乳的酸度为36．73。T，之后逐渐下降，15d之后在19．43-23．15。T之间变化；2h时乳密度、蛋白质、固形物分别为1．057、18．23％、31．460％，3d内迅速下降，然后分别在1．028～1．031、4．83％~6．02％、19．12％~20．59％之间变化：脂肪含量在2h为9．73％，之后逐步上升，36h时达到最高值11．57％，之后呈缓慢下降趋势，4d时为9．76％，之后在8．26％～9．06％之间变化：酪蛋白在粗蛋白中的比例逐步上升，2h时为40．15％，5d时达到79．13％，之后在81．07％～83．23％变化。     

Cuticular Hydrocarbons of Buffalo Fly, <Emphasis Type="Italic">Haematobia exigua</Emphasis>, and Chemotaxonomic Differentiation from Horn Fly, <Emphasis Type="Italic">H. irritans</Emphasis>

We determined the quantity and chemical composition of cuticular hydrocarbons of different strains, sexes, and ages of buffalo flies, Haematobia exigua. The quantity of cuticular hydrocarbons increased from less than 1 μg/fly for newly emerged flies to over 11 μg/fly in 13-d-old flies. The hydrocarbon chain length varied from C₂₁ to C₂₉, with unbranched alkanes and monounsaturated alkenes the major components. Newly emerged flies contained almost exclusively C₂₇ hydrocarbons. Increasing age was accompanied by the appearance of hydrocarbons with shorter carbon chains and an increase in the proportion of alkenes. 11-Tricosene and 7-tricosene were the most abundant hydrocarbons in mature H. exigua. Cuticular hydrocarbons of H. exigua are distinctly different from those of horn flies, Haematobia irritans. The most noticeable differences were in the C₂₃ alkenes, with the major isomers 11- and 7-tricosene in H. exigua and (Z)-9- and (Z)-5-tricosene in H. irritans, respectively. Cuticular hydrocarbon analysis provides a reliable method to differentiate the two species, which are morphologically difficult to separate. The differences in cuticular hydrocarbons also support their recognition as separate species, H. exigua and H. irritans, rather than as subspecies.     

Microvasculature of the buffalo (Bubalus bubalis) choroid plexuses: structural, histochemical, and immunocytochemical study

The choroid plexuses (CPs) in mammals produce the cerebrospinal fluid (CSF). In the literature, the morphology of CPs and the process that regulates the production of CSF are virtually nonexistent for domestic ruminants. Thus this study has two aims: 1. to investigate the morpho-structure of the buffalo CP microvasculature utilizing light microscopy (LM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques, and 2. to investigate the relationship between the blood vessels and both the elongated cells and the cells with multiple protrusions located in the CPs. SEM and TEM analyses of the CPs from buffalo brain showed morphological and structural features similar those reported in other mammalian species. Moreover the blood microvasculature is the major component responsible for the formation of the CSF, secreted by the encephalic CPs. In addition the chemical composition of this fluid depends on several morpho-functional characteristics of the vascularization of the CPs. These characteristics are as follows: two shapes of the vascular organization: lamina-like and ovoid-like elongated cells of the CPs, which connect the ventricular cavities to the blood capillaries; and the CP capillaries have diverse forms. In the present study the employment of NADPHd and NOS I was taken as indirect evidence for the presence of NO for investigation their specific role in CPs. Then NOS I immunoreactivity is found in the walls of CP blood vessels demonstrating indirectly the presence of NO with a vaso-dilatatory and autoregulation function of vascular tone by cholinergic nerve stimulation of blood vessel smooth muscle.     

Production of Afyon Kaymak with Traditional and Technological Methods

Afyon kaymak （milk cream） is traditional dairy product of Afyon city which is a junction of Middle Anatolia and West regions and famous with its thermal tourism and food. However, challenging production process led Afyon kaymak to lose its importance. Although buffalo milk is the raw material of traditional Afyon kaymak, cow milk can be used in the process. In traditional process, milk is filtered with double cheesecloth and gotten into the aluminum or tinned copper milk cream pans where the capacity is around 2.5-3.0 L. Half-filled pan is warm up to 90-95 ℃. Pans are carried to cool area and left until cooling. Milk cream on the cooled pans is lined by a pin. New milked milk is added to the lined cream in pans and heated for 1 h. It is covered and held on for 6-8 h. While holding period is until afternoon on summer time, it is until mid-afternoon in winter. Covers of the pans are opened and hold in a cool place until morning and, thus, cream is chilled. Cream layer on pans are lined and gotten out of pans. Cream as circle is divided into four pieces and left to the cream package after turning down. In this review, we aimed to give some information about Afyon kaymak and its production methods.     

水牛乳中主要过敏原的分离纯化

牛乳和水牛乳存在免疫交叉反应,牛乳过敏患者可能对水牛乳过敏。因此,分离纯化出水牛乳中各种过敏原将为进一步的工作奠定物质基础。实验中以摩拉水牛乳为原料,通过等电点沉淀、凝胶柱层析法和阴离子交换法分离纯化水牛乳的酪蛋白、β-乳球蛋白α-乳白蛋白,得到了SDS-PAGE纯(纯度≥90%)的β-乳球蛋白α-乳白蛋白。离子交换层析分离β-乳球蛋白、α-乳白蛋白的得率分别为50.26%、52.86%;凝胶层析分离β-乳球蛋白、α-乳白蛋白的得率分别为49.39%、84.19%。实验结果表明,等电点沉淀、凝胶柱层析法和阴离子交换法适合于分离水牛乳中主要过敏原成分。