Heibei Okamura (1852–1934) produced Japan's finest "Okamura's" chaulmoogra oil,, between about 1892 and 1944 at Sakai, Osaka, Japan. Chaulmoogra oil, which is taken from capsular fruits of Hydnocarpus genus trees of Thailand, Indonesia, Malaysia and the Philippines, had been the only one remedy in wide use before Guy Henry Faget proved the efficacy of promin in 1943 Promin started the era of sulfon chemicals and revolutionalized the treatment of leprosy.