assertion  retraction  graph  subject          predicate        object           datatype  annotation
1          0           graph  obo:CHEBI_22928  rdfs:subClassOf  obo:CHEBI_24471  _IRI      
1          0           graph  obo:CHEBI_23117  rdfs:subClassOf  obo:CHEBI_24471  _IRI      
1          0           graph  obo:CHEBI_37578  rdfs:subClassOf  obo:CHEBI_24471  _IRI