eCAM Advance Access published online on September 22, 2009
eCAM, doi:10.1093/ecam/nep147
In vitro activity of 2-methoxy-1,4-naphthoquinone and stigmasta-7,22-diene-3β-ol from Impatiens balsamina L. against multiple antibiotic-resistant Helicobacter pylori
1Department of Food Science and Biotechnology, National Chung Hsing University, Taichung, 2Division of Gastroenterology, Department of Internal Medicine, 3Graduate Institute of Healthcare Administration, College of Health Sciences, 4Faculty of Medicinal and applied Chemistry, Kaoshing Medical University, Kaohsiung and 5Department of Chemistry, National Chung Hsing University, Taichung, Taiwan, R.O.C.
Infection with Helicobacter pylori is strongly associated with gastric cancer and gastric adenocarcinoma. WHO classified H. pylori as a group 1 carcinogen in 1994. Impatiens balsamina L. has been used as indigenous medicine in Asia for the treatment of rheumatism, fractures and fingernail inflammation. In this study, we isolated anti-H. pylori compounds from this plant and investigated their anti- and bactericidal activity. Compounds of 2-methoxy-1,4-naphthoquinone (MeONQ) and stigmasta-7,22-diene-3β-ol (spinasterol) were isolated from the pods and roots/stems/leaves of I. balsamina L., respectively. The minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) for MeONQ were in the ranges of 0.156–0.625 and 0.313–0.625 µg ml–1, respectively, and in the ranges of 20–80 µg ml–1 both of MICs and MBCs for spinasterol against antibiotic (clarithromycin, metronidazole and levofloxacin) resistant H. pylori. Notably, the activity of MeONQ was equivalent to that of amoxicillin (AMX). The bactericidal H. pylori action of MeONQ was dose-dependent. Furthermore, the activity of MeONQ was not influenced by the environmental pH values (4–8) and demonstrated good thermal (121°C for 15 min) stability. MeONQ abounds in the I. balsamina L. pod at the level of 4.39% (w/w db). In conclusion, MeONQ exhibits strong potential to be developed as a candidate agent for the eradication of H. pylori infection.
Keywords: anti-Helicobacter pylori activity – antibiotic resistance – Impatiens balsamina L. – 2-methoxy-1,4-naphthoquinone – spinasterol
For reprints and all correspondence: Dr. Yuan-Chuen Wang, Department of Food Science and Biotechnology, National Chung Hsing University, 250 Kuo-Kuang Rd., Taichung, Taiwan, R.O.C. Tel: +886-4-2284-0385, ext.: 4220; Fax: +886-4-2285-4053; E-mail: ycwang{at}nchu.edu.tw
Received April 22, 2009; accepted August 30, 2009