野生竹红菌中总氮的测定

目的]为进一步研究竹红菌奠定基础。方法]用凯氏定氮法测定总氮含量,研究温度、消化时间及样品用量对野生竹红菌消化过程的影响。结果]野生竹红菌样品与硫酸钾、硫酸铜、硫酸的比例分别为1∶5、2∶1、1∶15时消化最佳。样品预处理条件和消化时间一致,温度为250~350℃时,不同的样品用量测定的总氮量没有较大差异。消化温度越高,样品中获得的粗蛋白和总氮越高,温度是影响消化的关键因素,并且消化温度越高所用的消化时间越短。结论]利用凯氏定氮法测定竹红菌中总氮的最优消化条件为样品量0.5 g左右,起始消化温度300℃,泡沫减少和烟雾变白后升高至350℃,消化时间4 h左右,在此条件下竹红菌的粗蛋白含量达22.50%,总含氮量达3.60%。

Detemination of Total Nitrogen in Wild Hypocrella bambusae

Objective] The aim of this study was to lay foundation for studying Hypocrella bambusae further.Method] The total nitrogen(N) content was determined with Kjeldahl to study the influences of temperature,digesting time and sample dosage on the course of digesting wild H.bambusae.Result] When the ratios of wild H.bambusae sample to potassium sulfate,copper sulfate and sulfate acid were 1∶5,2∶1 and 1∶15 resp.,the digestion was best.The pretreatment condition of sample accorded with digesting time.When the temperature was at 250～350 ℃,the total N amount determined with different sample dosages had no bigger difference.The higher the digesting temperature was,the more the crude protein and total N obtained from sample was.Temperature was the key factor influencing digestion and the higher the digesting temperature was,the shorter the consumed time in the digestion was.Conclusion] The optimum digesting condition of determining total N in H.bambusae with Kjeldahl was with about 0.5 g sample,initial digesting temperature at 300 ℃ and ascending to 350 ℃ after the foam reduced and smog whitened,and the digesting time of about 4 h,under which,the crude protein content was 22.50% and the total N content was 3.60% in H.bambusae.