中国健康青年男性赖氨酸需要量的研究

发布时间：2018-01-31 10:17

本文关键词： 赖氨酸稳定同位素丰度 ~(13)CO_2产生率氧化率二项回归曲线　出处：《扬州大学》2012年硕士论文　论文类型：学位论文

【摘要】：1研究背景我国民众以谷物膳食为主,蛋自质摄入以植物性来源为主,曾有某省的人群营养调查结果显示高达90%以上氨基酸模式不理想,其中第一限制性的氨基酸就是赖氨酸。赖氨酸是人体必需氨基酸之一、谷物的第一限制性氨基酸,明确其人体需要量对以谷类为主食的中国居民具有颇为重要的意义。缺乏赖氨酸的症状包括疲劳、虚弱、恶心、呕吐、头晕、没有食欲、发育迟缓、贫血.等。在谷类食品中强化赖氨酸以提高蛋白质营养价值的研究,国内外早有报道。Mack早在20世纪中叶就发现,在基础膳食中补充赖氨酸喂养儿童,体重增加及骨质密度增强等均优于未补充者,这说明赖氨酸可促进生长和骨钙沉着。然而任何营养素摄入都应该遵循适量的原则,也有许多研究报道了摄入过量赖氨酸引起的有害作用。目前我国尚未制定出适合中困居民膳食特点的赖氨酸推荐摄入量,相关研究也较少,及早制定出适合中国人群的必需氨基酸推荐摄入量的意义非常重大。本实验采用先进安全的指示剂氨基酸氧化法(13C-苯丙氨酸作为指示剂)来研究中国健康青年男性的赖氨酸生理需要量。 2研究目的本研究拟以中国当前的膳食模式下的健康成年男性作为研究对象,采用稳定同位素示踪技术,以13C-苯丙氨酸作为示踪剂,结合“2002年年中国居民营养与健康状况调查”资料所得出的中国居民代表性膳食结构,探讨我国健康成年男性的赖氨酸需要量,为制定我国不同性别、人群的必需氨基酸推荐摄入量提供科学依据,为我国的食品氨基酸强化和临床的氨基酸治疗提供理论支持。同时,将本研究结果与西方人种的结果进行比较,探讨不同人种对赖氨酸需要最的异同及其原因,为进步探索人体对氨基酸代谢的机制提供实验数据。 3研究方法木研究以中国当前的膳食模式的健康青年男性作为研究对象,预设5个赖氨酸摄入水平：65mg/(kg·d),55mg/(kg·d),45mg/(kg·d),35mg/(kg·d),25mg/(kg·d)。分为5个连续的实验周期,侮周为期7天。选择7名健康青年男性作为研究对象,每周1～6天为适应期,周日进行氨基酸代谢动力学研究。采用稳定同位素示踪技术,以13C-苯丙氨酸作为示踪剂进行人体氨基酸代谢实验,检测呼出气、血液中稳定同位素的丰度,计算氨笨酸的流量.和氧化率,通过观察比较在不同膳食赖氨酸摄入水平下,5个赖氨酸剂景组的苯丙氨酸氧化情况的变化规律来了解机体赖氨酸的氧化分解情况,建立赖氨酸摄入量与苯丙氨酸氧化率变化之间的二项回归曲线,计算回归曲线的拐点来确定赖氨酸的生理需要量。 4研究结果 13CO2产生率计算的赖氨酸生理需要量为57.08mg/(kg·d) 13C-苯内氨酸的氧化率计算的赖氨酸生理需要量53.46mg/(kg·d) 5结论在中国传统膳食模式卜,中国健康青年男性赖氨酸的生理需要量范围在50～60mg/(kg·d)。
[Abstract]:1 research background Most of the people in our country mainly eat cereals, and the natural intake of eggs is mainly from vegetative sources. The results of nutritional survey in one province showed that the pattern of amino acid was not satisfactory as high as 90% or more. The first limiting amino acid is lysine. Lysine is one of the essential amino acids in human body and the first limiting amino acid in cereals. Identifying their human needs is of great significance to Chinese residents who rely on cereals. Symptoms of lysine deficiency include fatigue, weakness, nausea, vomiting, dizziness, loss of appetite, and stunting. Anemia, et al. Studies on fortifying lysine in cereals to improve protein nutritional value have long been reported at home and abroad. Mack was found in the middle of 20th century to supplement lysine in basic diet to feed children. Weight gain and bone density were better than those without supplementation, suggesting that lysine promoted growth and osteocalcium. However, any nutrient intake should follow appropriate principles. There are also many studies reported on the harmful effects of excessive intake of lysine. At present, China has not yet developed a suitable dietary characteristics of the poor residents of lysine recommended intake, and there are few related studies. It is very important to determine the recommended intake of essential amino acids suitable for Chinese population as soon as possible. The advanced safe indicator amino acid oxidation method (13C- phenylalanine) was used as indicator in this experiment. To study the lysine physiological requirements of healthy young men in China. 2 purpose of research In this study, healthy adult males in the current dietary pattern in China were chosen as study objects, and 13C- phenylalanine was used as tracer by using stable isotope tracer technique. Based on the data of the 2002 Survey of Nutrition and Health status of Chinese residents, the lysine requirements of healthy adult males in China were discussed in order to formulate different sexes in China. The recommended intake of essential amino acids in the population provides a scientific basis for the strengthening of food amino acids and the clinical treatment of amino acids in China. At the same time, the results of this study are compared with the results of Western ethnic groups. To explore the most similarities and differences of lysine requirement among different species and its causes, and to provide experimental data for improving the mechanism of amino acid metabolism in human body. 3 research methods In this study, healthy young men in the current dietary pattern in China were selected as subjects, with 5 lysine intake levels of 5: 65 mg / kg / kg / d = 55 mg / kg 路d). 45 mg / kg / d ~ 35 mg 路kg 路d ~ (-1) ~ (25 mg 路d ~ (-1) ~ (-1) / kg / d) were divided into five consecutive experimental cycles. Seven healthy young men were selected as the study subjects. The amino acid metabolism kinetics was studied on Sunday. Stable isotope tracer technique was used to study the amino acid metabolism kinetics of 7 healthy young men during the adaptation period of 1 to 6 days a week. Amino acid metabolism experiments were carried out with 13C- phenylalanine as tracer to detect the abundance of stable isotopes in exhaled air and blood, and to calculate the flow rate and oxidation rate of aminobenzoic acid. In order to understand the oxidative decomposition of lysine, the changes of phenylalanine oxidation in five lysine groups were observed and compared under different dietary lysine intake levels. A binomial regression curve between lysine intake and phenylalanine oxidation rate was established and the inflection point of the regression curve was calculated to determine the physiological requirement of lysine. 4. Research results The Lysine physiological requirement calculated by 13CO2 production rate is 57.08 mg / kg 路d) The Lysine physiological requirement calculated by the Oxidation rate of 13C- phenylalanine: 53.46 mg / kg 路d) Conclusion In the traditional Chinese dietary pattern, the physiological requirement of lysine for healthy young Chinese males is in the range of 50 ~ 60 mg / kg 路d ~ (-1) 路d ~ (-1).
【学位授予单位】：扬州大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R151.1

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