Evaluating the anti-parasitic potential of fermented Moringa Oleifera leaf extract against Giardia lamblia in a controlled human gut microbiota model

Background: Giardia lamblia remains a leading cause of waterborne parasitic infection, and emerging resistance to metronidazole and related drugs highlights the need for alternatives that also support gut health. Fermented Moringa oleifera leaf extract may combine direct antiparasitic activity with microbiota modulation. Aim: To evaluate, in a controlled in-vitro human gut model, whether daily supplementation with 1% (v/v) fermented Moringa oleifera extract reduces Giardia antigen levels and beneficially alters gut microbial and metabolic profiles. Methods: Fifty batch fermenters inoculated with human fecal microbiota and Giardia trophozoites were randomized to control or Moringa treatment (n = 25 each) and followed for 7 days; Giardia antigen, short-chain fatty acids, fecal pH, ammonia, protease activity, and Bifidobacterium and Faecalibacterium prausnitzii counts were quantified. Results: The treatment group showed a marked reduction in Giardia antigen (2.23 ± 0.65 vs. 4.02 ± 0.78 ng/mL, p < 0.0001) and higher butyrate concentrations (4.38 ± 0.85 vs. 3.14 ± 0.78 mM, p < 0.0001), accompanied by increased Bifidobacterium and F. prausnitzii abundances (both p < 0.001) and lower fecal pH, ammonia, and protease activity (all p < 0.0001). Conclusion: Fermented Moringa oleifera extract exerted simultaneous antiparasitic and microbiota-modulating effects in this in-vitro human gut model, and these findings warrant subsequent evaluation in appropriate animal and human studies.