Even if Interest and remuneration is taxable in the hands of the partner as business income, we cannot say that that is his turnover. He cannot deduct any expenses from that. so, the whole amount has to be taxed and not just 8%.
I am aware that In the recent case of Usha Narayanan vs. DCIT (ITA 703/ Kol/2012), the AO held that the salary of a partner of a partnership firm is liable to tax as Profits & gains of Business or Profession under the Section 28(v) of the Act and accordingly levied penalty for failure to get books of accounts audited under Section 271B of the Act. This action was upheld by the Kolkata ITAT.
One may say that by same logic even 44AD can be applied to remuneration of a partner.
But in my opinion, section 44AD cannot be applied here as remuneration is not TURNOVER.