| چکیده انگلیسی مقاله |
Extended Abstract
Introduction and Objectives: Milk is a complex physiological and biological liquid that contains water, protein, lactose, fat, vitamins and minerals. Milk proteins (lactoferrin and lactoperoxidase) are known to have antimicrobial and immunomodulatory effects. More than half of the world's population consumes buffalo milk and milk products. Due to its unique properties, buffalo milk is highly regarded in developing countries, and its cultivation has existed in Iran for a long time. The main proteins of milk are casein and whey. Casein exists in the form of micelles, and 80% of milk proteins include alpha S1 casein, alpha S2 casein, beta casein, and kappa casein. Whey proteins are about 20% of milk proteins, which have four main components including betalactoglobulin, alphalactalbumin, bovine serum albumin and immunoglobulin. Proteins such as lactoferrin, peptone protease, calmodulin, prolactin, and folate-binding proteins are also found in milk and are considered accessory proteins. Milk proteins have positive effects on different structures of the body such as immune system, nervous system, digestive system and cardiovascular system. In addition, milk proteins are considered as a wide variety of biologically active peptides with superior nutritional and immunological activities. Therefore, obtaining complete information about the physicochemical properties of milk of different species and its nutritional value seems essential for liquid milk technology. Milk proteins have been continuously analyzed and the information about this very important and complex system has been increasingly increased in recent years, mainly due to technological advances. In addition, due to the increased knowledge of bioactive proteins in milk, the scope of research work on the analysis of proteins in milk has increased significantly. The present study was conducted with the aim of measuring total protein values of cow and buffalo milk samples in the climatic conditions of Khuzestan province. Also, the electrophoretic pattern of buffalo milk proteins was compared with cow milk.
Materials and methods: Milk samples were collected from 30 apparently healthy cows and 30 buffaloes from the surrounding villages of Shushtar city and cattle farms of Masjid Suleiman city. After that, raw milk proteins were evaluated by Kjeldahl method.
In order to measure milk proteins, first, milk was digested with the addition of sulfuric acid and with gentle heat. Complete digestion continues until the milk becomes colorless. After cooling, distillation was done by adding boric acid and methyl red, and the contents were titrated with 0.1 normal tetrazole sulfuric acid. The first color change marked the end of the titration. Finally, the amount of protein was calculated. In the next step, milk serum was separated and the amount of milk protein in these two types of animals was compared with sodium dodecyl sulfate plate method. In this technique, milk protein molecules are linearized using sodium dodecyl sulfate, and their movement is based on weight, so that the larger the protein, the shorter the distance traveled. The relationship between the distance traveled by proteins and the logarithm of their molecular weight was investigated and milk proteins were identified. T-test statistical analysis was used to compare the average total protein in cows and buffaloes. 95% confidence level was considered statistically significant (P<0.05).
Results: In sodium dodecyl sulfate plates, according to the protein marker, standard samples were able to create 14, 18, 22 and 70 kilodalton bands for alpha-lactalbumin, beta-lactoglobulin, casein and albumin proteins. The average protein of buffalo milk is equal to 4.71±1.79 mg/liter and for cow milk protein is 3.91±1.19 mg/liter, which means that the amount of total protein in buffalo milk is significantly higher than It is a cow (P>0.05). In addition, it was found that cow's milk has lower levels of beta-lactoglobulin and casein than buffalo's milk, while the amount of alpha-lactalbumin in cow's milk was higher than buffalo's milk. The bands obtained from the electrophoresis of casein and alpha-lactalbumin on the gel show that there is genetic diversity among the subunits of casein and alpha-lactalbumin in cow and buffalo milk.
Conclusion: In comparison of the protein profile in animal milks, there are various reports that show protein profiles of milk is different in animal species. So far, the protein profile of buffalo milk has not been compared, which was investigated in this study. In general, the present study shows that cow's milk and buffalo's milk are different in terms of the protein profile, and due to the higher amount of total protein and especially the amount of casein and beta-lactoglobulin in buffalo's milk compared to cow's milk. It seems that the nutritional value of buffalo milk is higher compared to cow milk. |
| نویسندگان مقاله |
مریم کریمی دهکردی | Maryam Karimi-Dehkordi
Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
دانشکده دامپزشکی، واحد شهرکرد، دانشگاه آزاد اسلامی، شهرکرد، ایران
حدیث کرم پور | Hadis Karam pour
Department of Food Industry Engineering, Faculty of Agriculture, Islamic Azad University, Shoushtar, Iran
گروه مهندسی علوم و صنایع غذایی، دانشکده کشاورزی، واحد شوشتر، دانشگاه آزاد اسلامی، شوشتر، ایران
سیده زینب پیغمبرزاده پیغمبرزاده | Seyede Zeinab Peighambarzadeh
Department of Veterinary medicine, Faculty of Agriculture, Islamic Azad University, Shoushtar, Iran
گروه دامپزشکی، دانشکده کشاورزی، واحد شوشتر، دانشگاه آزاد اسلامی، شوشتر، ایران
مجید غلامی آهنگران | Majid Gholami-Ahangaran
Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
گروه علوم بالینی، دانشکده دامپزشکی، واحد شهرکرد، دانشگاه آزاد اسلامی، شهرکرد، ایران
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