2.11. Organic Acid Analysis
To extract and identify organic acids from fecal samples, 500 mg of feces was weighed in duplicate and stored at −80 °C until further analysis. The frozen feces were thawed at room temperature (23 ± 2 °C) and homogenized with 1 mL of ultrapure water. Subsequently, the samples underwent centrifugation at 12,000× 