In vitro Antiurolithiatic Activity of Carabao Grass (Paspalum conjugatum) Extracts

Abstract

The mineralization of calcium oxalate deposits in the kidneys results from the crystallization of minerals in concentrated urine. Over time, these deposits form into kidney stones. Their formation is a symptom of deteriorating renal function and condition, for which we currently do not have a satisfactory treatment regimen. This study explored the ability of extracts of carabao grass (Paspalum conjugatum) to dissolve calcium oxalate crystals in vitro without significantly increasing the pH of the resulting solution, which researchers used as a marker for measuring toxicity. Calcium oxalate stones were produced from an aggregation assay using standard nucleation protocols, the concentration of which was determined using ultraviolet analysis spectrophotometry at 660nm. Researchers prepared carabao grass extracts by subjecting dried samples to Soxhlet extraction in ethanol. The solvent was removed using a rotary evaporator. The extract was divided into four concentrations (25%, 50%, 75%, and 100%). The calcium oxalate crystals were exposed to the extracts and the negative control. The resulting crystals were then weighed. The pH of the resulting solution was also measured. Results showed that a solution of the extract above 75% was able to dissolve calcium oxalate crystals at a significantly higher rate than concentrations of 50% and below. Results also showed that only the pure extract did not significantly alter the pH of the resulting solution above the normal range of human blood. Therefore, Carabao grass extracts exhibit in vitro antiurolithiatic activity. Researchers recommend expanding the study to cover the confirmatory testing of phytochemicals and cytotoxic studies.