In redeeming from a sale of a leasehold interest in agricultural college land, the amount to be paid shall include any amount paid by the holder of the certificate as interest or principal due by the terms of the lease or otherwise to prevent a forfeiture, and for which proper voucher has been filed with the county treasurer, with interest at eight percent per annum from date of payment, which amount shall be paid by the treasurer to the holder of the certificate, and the certificate of redemption shall show the amount paid by the party redeeming.