Table 2.

Comparison of commonly used metabolome databases.

Database	No. Records	Spectra	Metabolic pathway	Structural information	Free access	Website
NIST chemistry WebBook	31,000 compounds	MS	×	√	√	http://webbook.nist.gov/chemistry/
Golm metabolome database (GMD)	2,222 metabolites	MS	×	√	×	http://gmd.mpimp-golm.mpg.de/
Human metabolome database (HMDB)	217,920 metabolites	MS, NMR	√	√	×	http://www.hmdb.ca/
Kyoto encyclopedia of genes and genomes (KEGG)	18,920 metabolites and other small molecules	×	√	√	×	http://www.genome.jp/kegg/
Metabolite and tandem MS database (METLIN)	960,000 compounds	MS	×	√	√	http://metlin.scripps.edu/index.php
Small molecule pathway database	30,000 small molecule pathways	×	√	√	×	https://www.smpdb.ca/
Chemical entities of biological interest (ChEBI)	60,094 compounds	×	√	√	×	http://www.ebi.ac.uk/chebi/
Spectral data base (SDBS)	34,600 compounds	MS, NMR	×	√	×	http://sdbs.db.aist.go.jp/
BioCyc	20,005 pathways	×	√	√	√	http://biocyc.org
Reactome	11,291 proteins	×	√	√	×	http://www.reactome.org/
Livestock metabolome database (LMDB)	1,202 metabolites	MS	×	√	×	https://lmdb.ca/