Fig. 5From: Optimization of melanin pigment production from the halotolerant black yeast Hortaea werneckii AS1 isolated from solar salter in AlexandriaThree-dimensional surface plots showing the relationships between the tested significant variables and pigment formation by Hortaea werneckii AS1 and the optimal levels of the three factors as obtained from the maximum of the polynomial model. The three figures indicate (a) the interaction between CaCl2 and culture volume, (b) the interaction between CaCl2 and trace element and (c) the interaction between trace element and culture volumeBack to article page