芭樂心葉萃取物降血糖功效之研究

Hypoglycemic Efficacy of Guava Leaf Extract

張嘉婷(Chia-Ting Chang)

指導教授 ： 蔡建鈞

亞洲大學/健康學院/保健營養生技學系碩士班/碩士(2010年)

摘要

摘 要

依據本草綱目記載芭樂葉可以治療糖尿病。台灣因為氣候為亞熱帶所以一年四季都適合栽種芭樂樹。我們和彰化縣社頭鄉農會及栽種芭樂的農友合作，評估芭樂心葉茶產品，是否具者有降血糖之功效。
實驗過程中將芭樂心葉茶用甲醇萃取所得到的濃縮物，作分配層析，進而得到層析己烷層、乙酸乙酯層、丁醇層和水溶層之濃縮物，以及芭樂心葉直接用熱水萃取所得到的濃縮物，共六個樣品，測試其是否能抑制蛋白質酪胺酸磷酸酶-1B之酵素活性，而推論芭樂葉茶是否其有降血糖的功能。
本研究發現層析水溶層濃縮物可抑制蛋白質酪胺酸磷酸酶-1B的活性，其IC50 為0.031±0.004 mg/mL。此數據與芭樂心葉直接水萃濃縮物的IC50 (0.033±0.001 mg/mL)相當接近，而且此兩種水溶層是上述六個樣品中最能夠有效抑制PTP-1B活性的樣品。因此，推測芭樂心葉茶可以抑制蛋白質磷酸水解酶-1B的有效成分為水溶性的物質，所以推論可以利用熱水沖泡芭樂心葉茶的方式來飲用，進而達到降血糖的功效。

關鍵字：糖尿病、芭樂心葉茶、蛋白質酪胺酸磷酸酶-1B

關鍵字

糖尿病 ； 芭樂心葉茶 ； 蛋白質酪胺酸磷酸酶-1B

並列摘要

Abstract

Compendium of Materia Medica indicated that guava leaves may be used for treating subjects with diabetic conditions. Due to subtropical climate conditions, guava tree can be cultivated in large quantity throughout the year in Taiwan. We cooperated with guava framers and the farmer’s union at Shetou(社頭) District of Chunghwa County to study the blood glucose lowering potential of guava leaf by examining if guava leaf extract can inhibit protein tyrosine phosphatase-1B enzymatic activity.
Guava leaf was extracted with methanol extensively, and the extract was condensed for further partitioning. Solvents of different polarities were used in the serial partitioning; they include hexane, ethyl acetate, butanol and water. Guava leaf was also extracted directly with hot water, so a total of six fractions were obtained. These fractions were concentrated and tested for their effects on protein tyrosine phosphatase-1B (PTP-1B) enzymatic activity, which plays a major role at controlling insulin signaling and circulating blood glucose levels.
The water-soluble concentrate has an IC50 of 0.031 ±0.004 mg/mL when inhibiting protein tyrosine phosphatase-1B, while direct hot water extract has an of IC50 of 0.033 ±0.001 mg/mL, these two water soluble fractions are more potent than other fractions at inbiting PTP-1B enzyme activity in vitro.
Therefore, it is suggested that guava leaf tea can inhibit protein tyrosine phosphatase-1B activity, and the active ingredient be water-soluble.

Keywords: diabetic, guava leaf tea, protein tyrosine phosphatase-1B

並列關鍵字

diabetic ； guava leaf tea ； protein tyrosine phosphatase-1B

參考文獻

徐銘佛，孟于青，「應用化學標定法研究一氧化氮對酪胺酸磷酸水解酶的活性調控以促進胰島素的感受性」， 台灣大學生化科學研究所博士論文2010年。

Anastasi E., Dotta F., Tiberti C., Vecci E., Ponte E., Di Mario U., Insulin prophylaxis down-regulates islet antigen expression and islet autoimmunity in the low-dose Stz mouse model of diabetes. Autoimmunity. 1999;29:249-256.

Barford D., Structural Studies of Reversible Protein Phosphorylation and Protein Phosphatases. Biochem Soc Trans.1999;27:751–766.

Cheng F.C., Shen S.C., and Wu J. S., Effect of Guava (psidium guajava L.) Leaf Extract on Glucose Uptake in Rat Hepatocytes. Journal of Food Science. 2009;74:312-318.

Dadke S., Chernoff J., Protein tyrosine phosphatase 1B as a potential drug target for obesity. Disord. 2003;3(4):299-304.