采用丙酮、水、氯仿、乙酸乙酯和正丁醇连续萃取普洱茶,旋转蒸发后冷冻干燥得到氯仿层、乙酸乙酯层、正丁醇层以及剩余水层4个主要分离组分,利用不同的组分灌胃经过肥胖造模处理的ICR小鼠,与普洱茶总水提取物和减肥药左旋肉碱进行比较,研究普洱茶不同组分对ICR肥胖小鼠的降脂减肥作用。实验结果表明,普洱茶总水提取物、乙酸乙酯萃取组分、剩余水层组分均对肥胖ICR小鼠具有很好的降脂减肥作用。其中乙酸乙酯层和剩余水层抑制脂肪累积(抑制率分别是24.7%和22.5%)的效果略差于减肥药物左旋肉碱(抑制率38.8%),但在改善血清指标尤其是提高HDL-C水平方面(提高率为61.7%和73.4%)显著优于左旋肉碱(9.4%),肝脏指标检测也得到了类似的结论,揭示普洱茶降脂减肥作用的主要成分可能存在于乙酸乙酯层和(或)剩余水层中。
In this study, Pu-erh tea was extracted with acetone, water, chloroform, ethyl acetate, and n-butanol. then, the extraction was concentrated with rotary evaporation and dried with lyophilizer into chloroform layer, ethyl acetate layer, n-butanol layer and surplus water layer extracts, which were used to administer ICR obese mouse for analyzing the lipid-lowering and anti-obesity effects. The experimental results demonstrated that the pu-erh tea total extract, ethyl acetate extract and surplus water extract are all effective on lipid-lowering and anti-obesity of ICR obese mouse, and the effects of ethyl acetate extract and surplus water extract on inhibiting fat accumulation(inhibition ratio was 24.7% and 22.5%)was slightly less than those in the L-carnitine (38.8%), but the effect on improving HDL-C level(61.7% and 73.4%) significantly superior to that in the L-carnitine (9.4%), the similar results were obtained in the mice liver, which suggest that the key lipid-lowering and anti-obesity function components were existed in the ethyl acetate layer and (or) surplus water layer extracts of pu-erh tea.
[1] Labib M.The investigation and management of obesity[J]. J Clin Pathol, 2003, 56(1): 17-25.
[2] Grundy SM.Multifactorial causation of obesity: implications for prevention[J]. Am J Clin Nutr, 1998, 67(suppl 3): 563S-572S.
[3] 熊昌云, 彭远菊. 普洱市普洱茶产业现状与发展策略分析[J]. 茶叶, 2007(3): 165-168.
[4] Sano M, Takenaka Y, Kojima R, et al. Effects of pu-erh tea on lipid metabolism in rats[J]. Chem Pharm Bull (Tokyo), 1986, 34(1): 221-228.
[5] Yang T T, Koo M W.Hypocholesterolemic effects of Chinese tea[J]. Pharmacol Res, 1997, 35(6): 505-512.
[6] Kuo K L, Weng M S, Chiang C T, et al. Comparative studies on the hypolipidemic and growth suppressive effects of oolong, black, pu-erh, and green tea leaves in rats[J]. J Agric Food Chem, 2005, 53(2): 480-489.
[7] Kang J S, Lee W K, Lee C W, et al. Improvement of high-fat diet-induced obesity by a mixture of red grape extract, soy isoflavone and L-carnitine: implications in cardiovascular and non-alcoholic fatty liver diseases[J]. Food Chem Toxicol, 2011, 49(9): 2453-2458.