These fruits were washed, crushed, squeezed and
separated to the juices and the residues. The juices were filter-sterilized
and stored at 15 C for future use. The nitrogen sources in the Hestrin and Schramm media (Hestrin & Schramm, 1954) (2.0%
peptone, 0.5% yeast extract and 0.12% citric acid) were added to the
fruit juices, and the mixture was adjusted to pH 6 with disodium
hydrogen phosphate buffer (medium I)