Fate of Blastocystis in Homemade Koruk (Unripe Grape) Juice and on Juice-Treated Green Leafy Vegetables

This study aimed to evaluate the viability of Blastocystis in naturally produced koruk juice and on leafy salad greens treated with the juice. Additionally, the antiparasitic effect of koruk juice is to be evaluated by molecular docking analysis. Koruk juice was produced from unripe grapes. Blastocystis isolates were inoculated with koruk juice at different concentration levels. The isolates were also inoculated onto different salad greens, and the greens were dressed with koruk juice. Molecular docking was used to investigate the interactions between the organic acids found in koruk juice and the 6NO0 protein, which plays a critical role in Blastocystis physiology. In the control group, Blastocystis maintained viability for 60 min. However, treatment with 50% koruk juice reduced the number of viable Blastocystis cells by 100% within 30 min in culture. The number of live Blastocystis decreased from 73.25 (curly lettuce) to 97.65 (parsley), depending on the type of greenery, after 5 min in green salads dressed with 50% concentration of koruk juice. Molecular docking analysis revealed that the organic acids found in koruk juice exhibit a high binding affinity for the active site of the Blastocystis target protein. Citric acid showed the highest interaction score (−6.486 kcal/mol), whereas the control drug metronidazole had the weakest (−4.065 kcal/mol). The fact that all the organic acids exhibit a higher affinity than metronidazole confirms the antiparasitic effect of koruk juice at a molecular level. In conclusion, koruk juice has an anti-Blastocystis effect and can be used as a salad dressing on greens to improve and eliminate the risk of Blastocystis.

Practical Applications

This study shows that homemade koruk (unripe grape) juice can effectively reduce Blastocystis contamination on leafy salad greens. Using 50% koruk juice as a natural salad dressing may help improve the microbial safety of fresh salads in home kitchens, restaurants, or food service settings. 50% koruk juice eliminated Blastocystis in culture within 30 min. Koruk juice was the most effective on Blastocystis viability on parsley. Molecular docking showed strong binding of organic acids to Blastocystis protein.