An extraction, purification, and identification procedure was used to determine and isolate alkylresorcinol homologs in rye. The major alkylresorcinol homologs have saturated odd-numbered carbons with the predominant chain length of C15, C17, C19, C21, C23, and C25. Rye alk(en)ylresourcinol homologs of C17:0, C17:1, C19:0, C21:0, C23:0, and C25:0, including a C15:0 standard, were used to study their effects on thrombin-challenged human platelet thromboxane production. C15:0 at .02 mu-mol/L, C17:1 at .2 and 2-mu-mol/L, C19:0 at .02 mu-mol/L, C21:0 at 2 mu-mol/L, and C23:0 at .02 and 2 mu-mol/L, significantly stimulated thromboxane production approximately 30 to 65 percent. These stimulation effects of alk(en)ylresorcinol homologs can be interpreted via either their membrane disruptive or free radical scavenging properties.