In all cases in which the rights of beneficiaries under a charitable trust are involved, the Attorney General or the district attorney of the circuit in which the major portion of trust res lies shall represent the interests of the beneficiaries and the interests of this state as parens patriae in all legal matters pertaining to the administration and disposition of such trust. The Attorney General or the district attorney may bring or defend actions and, insofar as an action of this nature may be deemed an action against the state, the state expressly gives its consent thereto. The venue of such actions may be in any county in the state in which a substantial number of persons who are the beneficiaries of the trust reside. Process shall be directed to the Attorney General or to the district attorney of the circuit in which the major portion of the trust res lies. Service may be perfected by mailing a copy of the petition and process by the clerk of the superior court of the county in which it is filed to the Attorney General or to the district attorney of the circuit in which the major portion of the trust res lies. Any judgment determining rights under any charitable trusts shall be binding on the beneficiaries if the Attorney General or the district attorney of the circuit in which the major portion of the trust res lies is a party and is served as provided in this Code section.