import re


def iso_to_species(isotopologue):
    """
    Take 1H2-16O and turn it to H2O, or take 48Ti-16O and turn it to TiO
    """
    species = ""
    for element in isotopologue.split('-'):
        for s in re.findall(r'\D+\d*', element):
            species += ''.join(s)
    return species if len(species) > 0 else isotopologue