4.14. Antiamoebic and Antigiardial Activity
The chloroform, methanol, and water extracts of 12 medicinal plants, including Z. zerumbet, commonly used by AIDS patients in southern Thailand, were screened for potential anti-amoebic activity [52]. The extracts, at a concentration of 1000 μg/mL, were first tested against Entamoeba histolytica strain HTH-56:MUTM and HM1:IMSS growing in vitro and extracts that caused inhibition were chosen and retested with concentrations ranging from 31.25 to 1000 μg/mL against E. histolytica strain HM1:IMSS. The CEZZ and chloroform extract of Murraya paniculata, which exhibited the respective IC50 value of 196.9 and 116.5 μg/mL, were classified as being “moderately active.” In comparison, the chloroform extracts of A. galanga, Barleria lupine, B. pandurata, P. betle and P. chaba, which produced IC50 value ranging from approximately 46 and 91 μg/mL, and methanol extract of B. pandurata (IC50 of approximately 58 μg/mL), were classified as “active” because their IC50 values were less than 100 μg/mL. For validation of methods, metronidazole was used as a standard drug and produced an IC50 value of 1.1 μg/mL.
Various extracts of 12 medicinal plants commonly used by AIDS patients in southern Thailand were screened for potential anti-giardial activity [53]. The chloroform, methanol, and water extracts of the plants, in the doses ranged between 31.25–1000 μg/mL, and a reference drug, metronidazole, in the concentrations ranging between 0.625–20 μg/mL, were tested for their potential to inhibit the in vitro growth of Giardia intestinalistrophozoites. Despite the chloroform extract of A. galanga exerting the highest anti-giardial activity with IC50and MIC values of 37.73 and 125 μg/mL, the CEZZ together with the chloroform extract of B. pandurata,Eclipta prostrata, P. betle, and P. chaba and the methanol extract of B. pandurata and E. prostrate were classified as being active. The CEZZ produced MIC and IC50 values of 250 and 69.02 μg/mL, respectively, while the MEZZ and AEZZ showed no activity against G. intestinalis. Metronidazole was found to exhibit MIC and IC50 value of 2.5 and 0.48 μg/mL, respectively.