Effect of Allium sativum, Thunbergia laurifolia, and Eurycoma longifolia crude extracts on the minute intestinal fluke, Haplorchis taichui

Haplorchis taichui is the minute intestinal fluke (MIF), presents a significant public health concern in Thailand. Despite praziquantel (PZQ) being the main treatment, concerns over recurrent use and drug resistance have surfaced. Thus, local herbal alternatives effective against gastrointestinal parasites could be crucial for reducing issues, necessitating exploration of herbal sources for alternative treatments. The objective of this study is to evaluate the efficacy of crude extracts from Allium sativum, Thunbergia laurifolia, and Eurycoma longifolia against H. taichui newly excysted juveniles (NEJ). H. taichui NEJs were exposed to varying concentrations of A. sativum (5, 10, and 20 mg/ml), T. laurifolia, and E. longifolia (100, 200, and 400 mg/ml), alongside PZQ (20 mg/ml) and RPMI culture medium as controls. Motility assessment at different exposure times and morphological surface changes were conducted by scanning electron microscopy (SEM). Treatment with A. sativum, T. laurifolia, and E. longifolia inhibited motility in H. taichui NEJs, resulting in reduced relative motility (RM) values and survival index (SI). Significant differences were noted in A. sativum and E. longifolia treated groups, with T. laurifolia showing no significant differences compared to the negative control. Morphological damage, especially tegumental swelling, was evident across all treatment groups, notably severe in the A. sativum group. These findings suggest the potential effectiveness of crude extracts of A. sativum, T. laurifolia, and E. longifolia against H. taichui NEJs. However, further investigations are necessary to understand their mechanisms and key bioactive compounds for developing effective anti-parasitic agents against helminthic infections.