Disposing of interest money from different bank accounts

I have 5 bank accounts in india and all are giving interest on my deposited money. when i got interest i will write in my diary date and amount and after all banks have given interest i will add and sent all the amount to charity like patient or orphan for education etc. but this amount i will sent from one bank. my question is my method do doing interest money is correct or shall i withdraw cash from each bank separtely and pay for charity. please expplain the right method of interest payment.