【作者】 孙天玮；

【导师】 吴永尧；

【作者基本信息】 湖南农业大学 ， 生物化学与分子生物学， 2008， 硕士

【摘要】 魔芋是我国中西部山区的重要经济作物,在我国南方各省已逐渐形成和发展为一项相对独立的新兴农业产业,发挥了很好的扶贫致富和富民强县的作用。我国魔芋资源丰富,但是对其化学成分的研究仅集中在少数的几种,且缺乏系统性,另外魔芋加工下脚料的成分的研究与利用也甚少。因此,魔芋资源的挖掘和综合利用具有重要经济和社会效益。本文对有生产利用价值的3个分类学种花魔芋、白魔芋、珠芽魔芋的主要化学成分进行了比较,初步分析了魔芋加工下脚料的组成成分,并对加工下脚料中生物碱的提取分离条件进行了初步探讨,得到以下结果:对不同种魔芋的化学成分分析表明,白魔芋地下球茎的葡甘聚糖含量最高,占干物质的51.05%,珠芽魔芋地下球茎次之,花魔芋地下球茎最低,仅为41.05%;不同器官生物碱的分布从高到低依次为顶芽、芋皮、地下球茎,不同种魔芋地下球茎生物碱的提取液都在211 nm处有吸收峰;不同种魔芋的粗蛋白、游离氨基酸、粗脂肪的含量都有一定的差异,对脂肪的薄层层析分析表明,魔芋地下球茎至少含有7种不同类型的脂类;湿法加工的葡甘聚糖粘度显著性高于干法加工(P＜0.01),其中花魔芋球茎的加工后粘度达到27680 mPa.s。对魔芋加工下脚料成分分析表明,加工下脚料中还含有2.93%左右的葡甘聚糖,另外含有其他大量的碳水化合物:淀粉为29.37%、可溶性糖为8.94%、还原糖为2.39%、粗纤维为5.84%。加工下脚料生物碱的含量为0.41%,对生物碱的薄层层析和液相色谱分析表明,氯仿部分的生物碱的种类多于正丁醇部分。通过单因素和正交试验,得到加工下脚料中生物碱的提取最佳条件为:料液比1∶15,温度50℃,乙醇浓度为70%,pH为1,提取时间为3小时,在此工艺条件下,提取率可达到89%以上。比较了AB-8、HPD-100A、HPD-100、MA-3、HPD-700等大孔吸附树脂对魔芋加工下脚料中生物碱的吸附效果,AB-8的吸附效果最好,吸附容量为8.17mg/g。最佳的吸附条件为:pH为10,上样液的浓度为1.25 g/mL(相当于生药浓度),时间为5小时。最佳的解吸条件:6 BV,pH为4的70%乙醇溶液以2 BV/h的流速洗脱条件下,洗脱率达到88%以上。更多还原

【Abstract】 Amorphophallus Blume has been a major economic crop of the mountain in central and western China.It has been gradually formed and developed into a relatively independent emerging agricultural industry in the southern provinces of China,which has played an important role of helping the poor and enriching people and County.Amorphophallus Blume from China is rich in resources,but the studies of its chemical composition focused on only a few of the resources,and not systematic. There is a little of study and utilization of Konjac fly powder which is a kind of by-product in konjac processing.As a result,Mining resources and comprehensive utilization of Amorphophallus Blume will have important economic and social benefits.We have analyzed the chemical compositions of Amorphophallus albus, Amorphophallus rivieri,Amorphophallus bulbifer which have production value.Then we analyzed the composition of Konjac fly powder which is a kind of by-product in konjac processing.We also explored the extraction and isolation conditions of alkaloid from Konjac fly powder.The main results are mentioned in the following part.The decreasing order of content of glucomannan in underground bulbs was Amorphophallus albus＞Amorphophallus bulbifer＞Amorphophallus rivieri.The content of glucomannan from Amorphophallus albus and Amorphophallus rivieri was 51.05%and 41.05%respectively.The decreasing order of alkaloid content in different organs was terminal bud＞epidermis＞underground bulbs.We found that all alkaloids from underground bulbs of different species had absorption peak at 211 nm.The content of other chemical compositions such as protein,amino acids,fat from different species were different.We also found that underground bulbs contain seven different types of lipids at least with thin-layer chromatography.The viscosity of glucomannan which was extracted with wet milling technology was significantly higher than the viscosity of glucomannan which was extracted with dry milling technology.And the viscosity of glucomannan from Amorphophallus rivieri was up to 27680 mPa.s.After exploring the compositions of fly powder,we found that fly powder contains about 2.93%glucomannan.And there were a large number of carbohydrates from fly powder.The content of starch,soluble sugar,reducing sugar and crude fiber were 29.37%,8.94%,2.39%and 5.84%respectively.And its alkaloid content was up to 0.41%.With high performance liquid chromatography and thin-layer chromatography,we found that the kinds of alkaloids from the chloroform part were more than that of n-butyl alcohol part.We have found the optimum conditions for extracting alkaloid in fly powder by single factor and orthogonal test,which is as followed:the ratio of sample to alcohol was 1:15,the temperature of extraction was 50℃,alcohol concentration was 70%and the pH was 1.Under this condition,the extraction rate can reach 89%.With investigating the adsorption capacity of different macroporous resin,such as AB-8,HPD-100A,HPD-100,MA-3,HPD-700,and so on,the result show that AB-8 was the most effective and its absorption capacity of alkaloid was 8.17mg/g.The best conditions for absorption was as followed:the pH of sample was 10,the concentration was 1.25 g/mL(equivalent to the concentration of Health),the time was 5 hours.The best conditions for desorption was as followed:the volume of ethanol was 6 BV,the pH of ethanol was 4,alcohol concentration was 70%,the flow rate was 2 BV/h.And the washout rate can reach 88%.更多还原