無患子皂素定量及膜分離技術之探討

Quantification and membrane separation of saponin from Sapindus mukorossi

林信諾(Hsin-No Lin)

指導教授 ： 柯淳涵

國立臺灣大學/生物資源暨農學院/森林環境暨資源學研究所/碩士(2007年)

https://doi.org/10.6342/NTU.2007.10335

摘要

無患子在台灣早期就有用來清潔的紀錄，至少已有數百年的歷史。無患子除了含有皂素外還含有油脂，洗滌器物後會產生光澤，因此珠寶界直到今天仍用來清洗首飾。

本試驗比較五氯化銻法、HPLC、Vanillin-硫酸法三種皂素定量的方法的準確度；以分析型C18管柱進行皂素分離並以MALDI-TOF MS及1H、13C NMR進行結構確認；並以膜過濾的方式讓無患子的皂素濃縮，並去除糖類、有機酸等物質。

試驗結果顯示，在三種皂素定量方法的比較上，五氯化銻法在皂素含量低的時候，測得的值會略高於實際添加量；皂素含量高的時候，測得的值則會略低於實際添加量。HPLC法則正好相反，於低濃度的時候測得的值會略低於實際添加量，於濃度1%左右，檢測值會開始高於實際添加量。Vanillin-硫酸法的測得含量則一直是實際添加量的一半左右，這有可能是樣品添加了皂基，皂基對Vanillin-硫酸法的反應有所影響所致。在三種方法當中，以五氯化銻法測得的值最準確。

最後以C18分析型管柱收集的樣品中，於12分半左右所得的樣品經MALDI-TOF MS及1H、13C NMR測試後與文獻比對，其結構應為皂素結構。

在膜過濾方面，孔徑較大的膜，其過濾速度較快，而孔徑較小的膜雖然過濾速度較慢，不過可以藉由提升過濾系統的壓力來加快過濾速度。實驗所用的三種膜中，PW膜可以阻隔絕大多數的皂素，另外兩張膜雖然無法完全阻隔皂素，卻會對皂素的通過產生影響，使皂素通過膜的速度與溶劑通過膜的速度不同，導致最後皂素溶液的濃度還是有所提升。三種膜均無法阻隔糖類，只有PW膜因為孔徑較小，對糖類的通過影響力較大，必須施加較大的壓力才能促使糖類通過。與皂素的情形相同，三種膜雖然無法阻隔糖類，卻會影響糖類經過膜，導致糖類與溶劑的過濾速度有異，因此整體而言在迴流端的糖類濃度有增加的趨勢。有機酸因為皂素的影響，無法以UV或RI檢測器確實檢測其含量，只能以滴定的方式概略估計，結果顯示，滲透端和迴流端的有機酸濃度是差不多的，可見三種膜都不會有機酸通過。綜合所有的實驗條件，以PW膜在9 kgf / cm2下可達到最佳的濃縮皂素並去除糖類及有機酸的效果。

關鍵字

無患子 ； 皂素 ； 高效液相層析 ； 五氯化銻法 ； Vanillin-硫酸法 ； 膜過濾

並列摘要

The pericarp of soapnut (Sapindus mukorossi Gaertn) has been used for cleaning in Taiwan for hundred years. People also used it for burnishing jewels.
The aim of this work is to compare the accuracy among three saponin quantitative detection methods, Antimony Pentachloride Colorimetric assay, HPLC and Vanillin-Sulfuric acid assay; isolation and identification of major saponin component by BDS Hypersil C18 column, MALDI-TOF mass spectroscopy and 1H and 13C NMR; and concentrate the saponin in the pericarp of soapnuts and remove sugars and organic acids by membrane filtration.
Among the three saponin quantitative detection methods, the values analyzed by Antimony Pentachloride Colorimetric methods are higher than added value at lower concentration and lower than added value at higher concentration. On the contrary, the values analyzed by HPLC are lower than added value at lower concentration and higher than added value at higher concentration. The analyzed values by Vanillin-Sulfuric acid method are half of added values, this may because the effect of soap base. Among the three saponin analysis methods, the accuracy of Antimony Pentachloride Colorimetric method is better than other two methods.
After MALDI-TOF mass spectroscopy and 1H and 13C NMR test and compared with literature, the results showed that, among the finally collected fractions, fractions collected at about 12.5 min have the structure of saponin.
For membrane filtration, membrane with larger pore size will have higher flow rate. The flow rate of filtration can be increase by increasing the pressure of the system. Among the three membranes, PW membrane have the ability to block almost all of the saponins. Although other two membranes could not block all of the saponins, they could affect saponins to pass through, results in differences of passing rate between saponins and solvent. All the three membranes could not block sugars, only PW membrane do more affect than others because of smaller pore size. PW membrane needs applying more pressure to force sugars to pass through. Like saponins, all membranes could affect sugars to pass through results in differences of passing rate between sugars and solvent. Due to the affect by saponins, organic acids could not be detected by UV or RI detector. We can only analyze the approximate value by titration. Results show that, the organic acid concentrations between permeate and retentate are similar, indicating that all membranes would not affect organic acids to pass through. Among all conditions, the best condition to separate saponins from sugars and organic acids was PW membrane with pressure of 9 kgf / cm2.

並列關鍵字

Sapindus mukurossi ； saponin ； HPLC ； Antimony Pentachloride Colorimetric assay ； Vanillin-Sulfuric acid assay ； membrane filtration

參考文獻

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