This function identifies the reactants for a set of stoichometric reactions.
reactants(reactionList)A set of stoichiometric reaction with the following characteristics:
Arrows symbols must be given in the form '=>' or '<=>'
Inverse arrow symbols '<=' or other types as: '-->', '<==>', '->' will not be parsed and will lead to errors.
Arrow symbols and plus signs (+) must be surrounded by a space character
Stoichiometric coefficients must be surrounded by a space character and not by parentheses.
Each metabolite must have only one stoichiometric coefficient, substituents must be joined to metabolite name by a hyphen (-) symbol.
Exchange reactions have only one metabolite before arrow symbol
Compartments must be given between square brackets ([compartment]) joined at the end of metabolite name
Some examples of valid stoichiometric reactions are:
H2O[c] + Urea-1-Carboxylate[c] <=> 2 CO2[c] + 2 NH3[c]
ADP[c] + Phosphoenolpyruvate[c] => ATP[c] + Pyruvate[c]
CO2[c] <=>
A vector with the identified reactants in the reaction, or a list with the identified reactats in each reaction if a set of stoichiometric reactions was given.