芝麻中lignans之分離純化及芝麻粕之利用

Isolation and purification of sesame lignans and utilization of sesame meal

鄭培益(Poi-Yik Teh)

指導教授 ： 李敏雄

國立臺灣大學/生物資源暨農學院/農業化學研究所/碩士(2008年)

https://doi.org/10.6342/NTU.2008.10183

摘要

本研究建立一種由芝麻油中分離純化sesamin及sesamolin之簡易方法。首先以n-Hexane稀釋芝麻油，然後通入矽膠管柱，接著依序以n-Hexane、n-Hexane-EtOAc (9:1)及EtOAc流洗。HPLC分析結果顯示n-Hexane-EtOAc (9:1)可以區分出sesamolin，回收率達80.9%，減壓濃縮去除溶劑後，以n-Hexane洗淨得sesamolin結晶。EtOAc 區分層含高濃度之sesamin，回收率達96.3%，減壓濃縮後以少量EtOAc回溶靜置而得sesamin結晶析出。將兩種結晶以n-Hexane洗淨後再使用不同溶劑進行再結晶。

脫脂芝麻粕以80%甲醇水溶液萃取，過濾後減壓濃縮去除溶劑得lignan glycosides粗萃物。利用不同管柱層析法(Amberlite XAD-16、Diaion HP-20、cellulose及silica gel)分離純化sesaminol triglucoside。結果以Diaion HP-20區分sesaminol triglucoside回收率達94.5%，純化倍數則可以提升為80%甲醇粗萃物之9.3倍。以cellulose管柱搭配Diaion HP-20管柱進行純化，純化倍數則可提高18.9倍，回收率達87.2%。

以HPLC分析不同品種芝麻之lignans含量，分析結果顯示每克芝麻平均含3.03 mg sesamin，含量範圍為1.42~6.42 mg。Sesamolin平均含量為1.76 mg，含量範圍為0.92~3.34 mg。Sesaminol triglucoside平均含量為1.21 mg，含量範圍為0.20~2.02 mg。各種芝麻之粗脂肪平均含量為44.8%，含量範圍為40%~48%。

使用芝麻粕(含蛋白質40~50%)來釀造芝麻醬油，經過180天室溫發酵熟成後，醬油製造之相關分析值為：總氮(TN) 1.55%、甲醛態氮(FN) 0.72%、胺基態氮(AN) 0.58%、水解率(DH) 46.5%、TNUR(%) 71.2%、pH值4.9及氯化鈉(NaCl) 17.1%。出麴料之蛋白酶活性為211±7 units/g of koji，澱粉酶活性為67±1 units/g of koji。

關鍵字

芝麻 ； 木酚素 ； 芝麻素 ； 芝麻酚林 ； 芝麻素酚三葡萄糖苷醬油

並列摘要

Sesamin, esamolin and sesaminol triglucoside in sesame seeds are major lignans that display an abundance of biological activities such as cholesterol-lowering, anticancer, antihypertensive, inhibits lipid peroxidation, antioxidant, enhancement of vitamin E level, protect liver and improve liver function.

In this study, we developed a simple and rapid method for isolation and purification of sesamin and sesamolin from sesame oil by silica gel column chromatography. First of all, sesame oil was diluted with n-Hexane, after that load into silica gel column，stepwise eluted with n-Hexane、n-Hexane-Ethyl acetate (9:1)、Ethyl acetate and Acetone。The n-Hexane-Ethyl acetate (9:1) fraction content high concentration of sesamolin, this separated process could be recover 80.9% of sesamolin. The Ethyl acetate fraction content high concentration of sesamin, that could be recover 96.3% of sesamin. Solvent was removed under vacuum with a rotary evaporator, sesamin and sesamolin crystal were washed with n-Hexane. Sesamin and sesamolin were recrystal with various of solvents.

Defatted sesame meal was extracted with 80% methanol to obtain a crude extract containing sesaminol glucosides. Isolation and purification of sesaminol triglucoside by various column chromatography such as Amberlite XAD-16、Diaion HP-20、cellulose and silica gel column。As a result，isolation and purification of sesaminol triglucoside by Diaion HP-20 column chromatography will increased 9.3 fold of sesaminol triglucoside compared with 80% MeOH crude extract, that could be recover 94.5% of sesaminol triglucoside. Cellulose column combined with Diaion HP-20 column chromatography will increased 18.9 fold and recovered 87.2% of sesaminol triglucoside.

A quantitative analysis of lignans in 10 varieties of sesame seeds by HPLC. The content of sesamin in 1 g sesame seeds ranged from 1.42 to 6.42 mg with an average value of 3.03 mg; Sesamolin ranged from 0.92 to 3.34 mg with an average value of 1.76 mg; Sesaminol triglucoside ranged from 0.20 to 2.02 mg with an average value of 1.21 mg。Crude fat ranged from 40 to 48%with an average value of 44.8%.

The sesame meal is the main by-product during sesame oil manufacturing. Although sesame meal content 40~50% protein and lignan glycosides, it seldom use in food processing, mainly used as a fertilizer and feeds. The purpose of this research is to produce sesame soy sauce products from the sesame meal, after 180 day fermentation and aging at room temperature, the general compositions of sesame soy sauces were respectively described as following total nitrogen 1.55%, formol nitrogen 0.72%, amino nitrogen 0.58%, degree of hydrolysis 46.5%, total nitrogen ultilization ratio 71.2% and sodium chloride 17.1%. The content of protease and amylase activity in 1 g koji were 211±7 units and 67±1 units.

並列關鍵字

sesame seed ； lignans ； sesamin ； sesamolin ； sesaminol triglucoside ； soy sauce

參考文獻

郭錦富，(1991)，原料比例對醬油品質之影響。國立台灣大學農業化學所博士論文。

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