Pellet diameter and morphology of European Ganoderma pfeifferi in a repeated-batch fermentation for exopolysaccharide production by Supramani, Sugenendran, Jailani, Nurulhuda, Ramarao, Kivaandra, Mohd Zain, Nurul Amalina, Klaus, Anita, Ahmad, Rahayu, Wan-Mohtar, Wan Abd Al Qadr Imad