Hyocholic acid is a primary bile acid in pigs and other mammals. [1] It has also been found in urine samples from patients with cholestasis. [2] Hyocholic acid is converted by gut microflora primarily to taurohyocholate and, to a lesser extent, taurocholic acid and tauro-β-muricholic acid in mice.[3] Hyocholic acid has low toxicity against human hepatoma HepG2 cells.[3][4]

Reference
[1]. Lundell, K., and Wikvall, K. Species-specific and age-dependent bile acid composition: Aspects on CYP8B and CYP4A subfamilies in bile acid biosynthesis. Curr. Drug Metab. 9(4), 323-331 (2008).
[2]. van Berge Henegouwen, G.P., Brandt, K.H., Eyssen, H., et al. Sulphated and unsulphated bile acids in serum, bile, and urine of patients with cholestasis. Gut 17(11), 861-869 (1976).
[3]. Wang, D.Q.-H., Tazuma, S., Cohen, D.E., et al. Feeding natural hydrophilic bile acids inhibits intestinal cholesterol absorption: Studies in the gallstone-susceptible mouse. Am. J. Physiol Gastrointest. Liver Physiol. 285(3), G494-G502 (2003).
[4]. Perreault, M., Bialek, A., Trottier, J., et al. Role of glucuronidation for hepatic detoxification and urinary elimination of toxic bile acids during biliary obstruction. PLoS One 8(11), e80994 (2013).