animal experiment animal model antineoplastic activity article controlled study drug screening female gomphrena martiana extract intraperitoneal drug administration male mouse nonhuman plant extract sarcoma 180 unclassified drug 5,6,7-Trisubstituted flavonoids Antitumor activity Cytotoxicity Ehrlich ascites tumor Gomphrena martiana animal cell cancer cell culture cancer graft cell culture cytotoxicity drug activity flavonoid fractionation gomphrena boliviana extract gomphrena extract