Catalyzes the hydrolysis of acyl-CoAs into free fatty acids and coenzyme A (CoASH), regulating their respective intracellular levels (PubMed:11673457). Displays no strong substrate specificity with respect to the carboxylic acid moiety of Acyl-CoAs (PubMed:11673457). Hydrolyzes medium length (C2 to C20) straight-chain, saturated and unsaturated acyl-CoAS but is inactive towards substrates with longer aliphatic chains (PubMed:11673457). Moreover, it catalyzes the hydrolysis of CoA esters of bile acids, such as choloyl-CoA and chenodeoxycholoyl-CoA and competes with bile acid CoA:amino acid N-acyltransferase (BAAT) (PubMed:11673457). Is also able to hydrolyze CoA esters of dicarboxylic acids (PubMed:16141203). It is involved in the metabolic regulation of peroxisome proliferation (By similarity). choloyl-CoA + H2O = cholate + CoA + H(+) chenodeoxycholoyl-CoA + H2O = chenodeoxycholate + CoA + H(+) acetyl-CoA + H2O = acetate + CoA + H(+) H2O + malonyl-CoA = CoA + H(+) + malonate acetoacetyl-CoA + H2O = acetoacetate + CoA + H(+) H2O + propanoyl-CoA = CoA + H(+) + propanoate butanoyl-CoA + H2O = butanoate + CoA + H(+) H2O + succinyl-CoA = CoA + H(+) + succinate glutaryl-CoA + H2O = CoA + glutarate + H(+) H2O + hexanoyl-CoA = CoA + H(+) + hexanoate H2O + hexanedioyl-CoA = CoA + H(+) + hexanedioate H2O + octanoyl-CoA = CoA + H(+) + octanoate H2O + octanedioyl-CoA = CoA + H(+) + octanedioate decanoyl-CoA + H2O = CoA + decanoate + H(+) decanedioyl-CoA + H2O = CoA + decanedioate + H(+) dodecanoyl-CoA + H2O = CoA + dodecanoate + H(+) dodecanedioyl-CoA + H2O = CoA + dodecanedioate + H(+) H2O + tetradecanoyl-CoA = CoA + H(+) + tetradecanoate (9Z)-tetradecenoyl-CoA + H2O = (9Z)-tetradecenoate + CoA + H(+) H2O + hexadecanoyl-CoA = CoA + H(+) + hexadecanoate (9Z)-hexadecenoyl-CoA + H2O = (9Z)-hexadecenoate + CoA + H(+) H2O + octadecanoyl-CoA = CoA + H(+) + octadecanoate (9Z)-octadecenoyl-CoA + H2O = (9Z)-octadecenoate + CoA + H(+) (9Z,12Z)-octadecadienoyl-CoA + H2O = (9Z,12Z)-octadecadienoate + CoA + H(+) eicosanoyl-CoA + H2O = CoA + eicosanoate + H(+) (5Z,8Z,11Z,14Z)-eicosatetraenoyl-CoA + H2O = (5Z,8Z,11Z,14Z)-eicosatetraenoate + CoA + H(+) 4,8-dimethylnonanoyl-CoA + H2O = 4,8-dimethylnonanoate + CoA + H(+) 2,6-dimethylheptanoyl-CoA + H2O = 2,6-dimethylheptanoate + CoA + H(+) (3S)-hydroxy-3-methylglutaryl-CoA + H2O = 3-hydroxy-3-methylglutarate + CoA + H(+) 3alpha,7alpha,12alpha-trihydroxy-5beta-cholestan-26-oyl-CoA + H2O = 3alpha,7alpha,12alpha-trihydroxy-5beta-cholestan-26-oate + CoA + H(+) 2-methyloctadecanoyl-CoA + H2O = 2-methyloctadecanoate + CoA + H(+) H2O + prostaglandin F2alpha-CoA = CoA + H(+) + prostaglandin F2alpha Inhibited by CoASH (IC(50)=10-15 uM). Also inhibited by cysteine-reactive agents. In summary, KM for medium- to long-chain acyl CoAs is in the order 1.4-6.7 uM, and with short-chain acyl CoAs range from 8 to 30 uM. KM for bile acid-CoA esters is in the range 6-15 uM. Lipid metabolism; fatty acid metabolism. homodimer. Predominantly localized in the peroxisome but a localization to the cytosol cannot be excluded. Ubiquitous. Induced in the liver, by peroxisome proliferator or fasting via the peroxisome proliferator-activated receptors (PPARs). Diurnal regulation of its expression. Constitutes about 1% of total peroxisomal protein. Belongs to the C/M/P thioester hydrolase family.