levulinic acid molecule, is a crystalline keto acid prepared from levulose, inulin, starch. structural chemical formula and

acetopropionic acid atom atomic biofuel carbon cellulose chain chemical chemistry compound education element formula hexose hydrogen illustration isolated keto ketovaleric laevulinic levulinate levulinic macromolecule model molecular molecule organic oxopentanoate oxopentanoic oxygen precursor science starch structure study vector