痤瘡(Acne)為皮膚皮脂腺開口因油脂或髒污堵塞而形成的病變結構，皮脂腺受到阻塞後 便可能會引起痤瘡桿菌(Propionibacterium acnes, PA) 、表皮葡萄球菌(Staphylococcus epidermidis, SE)及金黃色葡萄球菌(S. aureus, SA)等皮膚表棲伺機細菌的滋生，過去常用抗生 素作為治療手段，而目前已發現抗藥性的痤瘡桿菌族群，因此亟需尋找能代替抗生素做為治 療痤瘡的天然萃取物。本研究以濾紙圓盤擴散法測試121 種市售中藥的水萃取液對上述三種 細菌的抑制效果，以10 倍萃取液測試三種細菌的感受性時，發現含有丁香、虎杖、訶子、地 榆等13 種中藥萃取液的濾紙圓盤，能產生明顯的抑菌區。進一步稀釋至100 倍時，訶子、大 黃、五倍子與蘆薈膠，仍能產生明顯的抑菌效果。分別將四種中藥萃取液與市售的天然抗菌 劑葡萄柚籽萃取液稀釋為200 倍至1000 倍，測試其對三種皮膚表棲細菌的抑制效果，結果顯 示，五倍子水萃取液對PA、SE、SA 等三種細菌的最小抑菌區產生倍數皆為600 倍；訶子與 大黃在200 倍的稀釋倍數下，對三種細菌皆無法產生抑菌區，蘆薈膠在300 倍時仍能對PA 產 生抑菌區，而市售的葡萄柚子萃取物FA-100 對SE 與PA 的最小抑菌圈產生倍數分別為200 與500 倍。本研究結果顯示，多種市售中藥的水萃取液皆能對痤瘡桿菌、表皮葡萄球菌與金 黃葡萄球菌產生抑制作用，其中又以五倍子抑制效果最佳，抑制菌種最多；而目前已作為保 養品添加成分的葡萄柚子萃取液是天然的抗菌劑，其對痤瘡桿菌同樣具有強烈的抑菌作用， 具有發展成抗痘護膚保養品的潛力。

Acnes are formed when the opening of sebaceous gland blocked with grease or dirt, and become to inflammatory acne. Propionibacterium acnes (PA), Staphylococcus epidermidis (SE), and S. aureus (SA) will multiply in blocked acnes and then develop the inflamed symptom. Antibiotics could relieve the symptoms, but they also induce the resistance of the causal bacteria. In this study, Chinese medicines are used to screening for their ability to inhibiting the growth of their causal microorganisms. The inhibitions of the 10-fold dilute aqueous extracts of 121 Chinese medicines to three skin acne-causing bacteria were screening by paper disc diffusion method. Results showed that the 10-fold dilute aqueous extracts of clove, knotweed and other eleven Chinese medicines could inhibit all three test bacteria. When the aqueous extracts dilute to 100-fold, the herbs as myrobalan, rhubarb, gallnut and aloe gel still have the inhibition activity. These four herbs and grapefruit seed extracts (FA-100) were tested for their inhibition potency, result showed when gallnut extracts could produce the minimum inhibition zone to three test bacteria when the dilution rate as 600-fold. The aqueous extract of myrobalan and rhubarb couldn’t produce the inhibition zone to three bacteria when the dilution rate as 200-fold. The aqueous extract of Aloe gel only inhibiting to PA when the dilution rate as 300-fold. The grapefruit seed extract FA-100 could produce minimum inhibition zone to SE and PA when the dilution rate as 200- and 500-fold, respectively. The results revealed many Chinese medicines could product activity ingredients to inhibitory acne-causing bacteria. In this study, the aqueous extract of gallnut has the powerful antibiotic ability. The grapefruit seed extract also has strong ability to inhibitory the acne-causing bacteria, especially on P. acnes. These materials that proven could be good alternate sources for acne therapy.