Abstract: A process for producing a substance KF-1040A represented by formula (I), and another substance KF-1040B represented by formula (II), which comprises culturing microorganisms capable of producing the substances KF-1040A and KF-1040B, thus accumulating these KF-1040A and/or KF-1040B in the liquid culture and harvesting the same from the culture. Because of the activities of inhibiting diacyloglycerol transferase and sphingomyelinase, the above substances are useful in preventing and treating arteriosclerosis, obesity, thrombus, inflammation and immune function-related diseases.

Abstract: A FO-1289 substance of the formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are hydrogen or acyl. A process for the production thereof comprises culturing the novel microorganism Aspergillus sp. FO-1289 FERM BP-4242 in a nutrient medium, accumulating the FO-1289 substance thus produced in the medium, and isolating the FO-1289 substance therefrom. Particular species of the FO-1289 substance comprise FO-1289A, in which R.sub.1, R.sub.2 and R.sub.3 are acetyl and R.sub.4 is hydrogen; FO-1289B, wherein R.sub.1 is propionyl, R.sub.2 and R.sub.3 are acetyl and R.sub.4 is hydrogen; FO-1289C, wherein R.sub.1 and R.sub.3 are acetyl, R.sub.2 is propionyl and R.sub.4 is hydrogen; and FO-1289D, wherein R.sub.1 and R.sub.2 are acetyl, R.sub.3 is propionyl and R.sub.4 is hydrogen.