鞣花酸(Ellagic acid)是一種廣泛存在於水果及堅果類如覆盆子、草莓中屬於多酚類(polyphenol)的一種。經研究發現鞣花酸具有抗氧化的特性，可以消除致癌物的作用，預防它們將正常的細胞轉變成癌細胞。王,2005 年亦證實鞣花酸可能具有抗發炎的特性。除紫外線外，類似發炎物質如組織胺等，也會造成自由基產生，加速黑色素生成的氧化反應。因此，不少美白保養品都添加甘草、洋甘菊、桑椹根部、牡丹根部萃取等抗氧化、抗發炎成分，避免肌膚因發炎而加速黑色素的產生。而鞣花酸基於抗發炎、抗氧化等特性，可以阻隔酪氨酸酶的活化，抑制黑色素的生成，具有美白之功效，所以越來越多化妝品保養製品都開始添加。本實驗主要探討鞣花酸凝膠劑型之特性，評估其安定性與化學穩定性，其後進行安全性評估，另外亦探討塗抹後皮膚含水率之變化情形。鞣花酸凝膠在0℃、25℃及50℃下，儲存35 天後，安定性佳。表二得知鞣花酸凝膠之pH 值在貯存14 天後即開始趨向平穩，平均pH 值落在4.6±0.2 之間。根據(Draize et al.,1948)的評分法，顯示皆無過敏反應發生。各組別塗抹凝膠後之皮膚pH 值下降至偏酸性範圍顯示安全性佳。在皮膚含水量測試方面，連續42 天使用含鞣花酸凝膠，皮膚含水量明顯高出控制，顯示鞣花酸具有增加皮膚之保濕能力。

Ellagic acid is a phenolic compound present in fruits and nuts, such as raspberries,strawberries and walnuts. It is known to inhibit certain carcinogen-induced cancers and haveother chemopreventive properties. Research in cell cultures and laboratory animals has foundthat ellagic acid may slow the growth of some tumors caused by certain carcinogens. Ellagicacid is an antioxidant found in numerous fruits and its topical application may prevent theformation of wrinkles. Some studies also suggest it may have a photo-protective effect.The objectives of the study are to explore the water extracts of ellagic acid on skin carecosmetics. The study includes 1. To prepare and characterize the moisture gel containingellagic acid water extracts. The characteristics of cream studied including storage stability,the safety and pH of the products, 2. Determining the water holding capacity change. Theresults obtained are:The safety test result in no erythema based on the Draize sore test. The gel pH did not changeand are stable after 0℃, 25℃ for 35 days, or high temperature storage at 50℃ for 35 days.Skin moisture capacity in terms of electrical capacitance increase after applying moisture gelcontained ellagic acid.In conclusion, moisture gel containing ellagic acid is safety and improved skin water holdingcapacity