Abstract Background Giardia lamblia, a protozoan parasite causing Giardiasis, that is epidemic in the developing countries, is commonly treated with drugs like metronidazole, though resistance and side effects drive interest in herbal alternatives. Methods The ethanolic extracts of Ginger (Zingiber officinale), Pomegranate (Punica granatum), and Fennel (Foeniculum vulgare) were prepared and subjected to qualitative phytochemical analysis to detect the presence of alkaloids, flavonoids, saponins, tannins, and polyphenols. Stool samples were collected from patients and Giardia lamblia cysts were isolated. For in vivo experiments, 36 four-week-old BALB/c mice were used. Each mouse was orally inoculated with 0.5 mL of the Giardia cyst suspension (9000 cysts/mL). Infection was confirmed by microscopic examination of fecal samples five days post inoculation. The mice were treated with 300 mg/kg of extracts for 7 days, and the anti-Giardia efficacy of extracts were tested by measuring cyst counts and reduction percentages over 20 days. Blood was drawn from the orbital vein after infection in mice and before treatment and again on day 14 of infection. Serum was obtained by centrifuging blood samples. IgE levels were measured using the Roche Elecsys device, which uses sandwich immunoassay technology that relies on streptavidin binding and electrochemiluminescence. Results All three plants share several phytochemical constituents (tannins, flavonoids, and polyphenols), but there are distinct differences in the presence of saponins and alkaloids among them. Early intervention (Day 5): Among all treatments, fennel showed the greatest initial cyst reduction (50.8%), followed in decreasing order by ginger (43.9%) and finally metronidazole (22.1%). Pomegranate behaved poorly in terms of showing an early effect. Mid-treatment (Day 10): Metronidazole was the foremost (88.1%), with fennel next (82.2%), followed in decreasing order by ginger (76.7%) and then pomegranate (69.5%). Day 20: Metronidazole remained the most effective (98.1%) while fennel (90.9%) and ginger (90.5%) were approaching similar efficacy, and pomegranate having attained (81.3%). IgE modulation: All extracts counteracted the elevated levels of IgE post-treatment; however, among all, pomegranate was the most potent in achieving a maximum reduction (45%), with ginger being next at (33%), followed by fennel at (30%) and metronidazole at (28%). Conclusion Fennel and ginger extracts show promising anti-Giardia activity, especially in cyst reduction, while pomegranate extract, although slower in initial antiparasitic action, excels in modulating immune response by significantly reducing IgE levels. These findings support the potential of these plant extracts as adjunct therapies for giardiasis, combining antiparasitic effects with immune modulation, which may enhance treatment outcomes and reduce reliance on conventional drugs with side effects.
Dakah et al. (Sat,) studied this question.