Production and Cytotoxicity of Extracellular Insoluble and Droplets of Soluble Melanin by Streptomyces lusitanus DMZ-3

Table 1

Optimization of critical process variables employing response surface method for the production of insoluble melanin by Streptomyces lusitanus DMZ-3.

Run	Critical process variables				Melanin production (g/L)
	𝑋1: 𝐴: Temperature °C	𝑋2: 𝐵: pH	𝑋3: 𝐶: Tyrosine %	𝑋4: 𝐷: Beef extract %	Actual value	Predicted value
1	42.50	7.75	1.25	1.25	4.35	4.35
2	42.50	7.75	1.25	1.25	4.35	4.35
3	35.00	7.00	0.50	2.00	1.08	2.12
4	35.00	8.50	2.00	2.00	3.05	3.51
5	27.50	7.75	1.25	1.25	2.12	1.90
6	35.00	8.50	2.00	0.50	4.21	3.73
7	42.50	7.75	1.25	1.25	4.35	4.35
8	42.50	7.75	2.75	1.25	4.05	3.91
9	50.00	8.50	2.00	0.50	5.29	4.65
10	42.50	9.25	1.25	1.25	3.15	3.35
11	35.00	7.00	2.00	2.00	3.11	2.99
12	50.00	7.00	0.50	0.50	1.63	1.57
13	35.00	7.00	2.00	0.50	2.41	2.91
14	50.00	8.50	2.00	2.00	3.92	4.53
15	57.50	7.75	1.25	1.25	2.16	2.27
16	42.50	7.75	1.25	1.25	4.35	4.35
17	50.00	8.50	0.50	2.00	1.55	1.44
18	35.00	8.50	0.50	2.00	1.53	1.38
19	42.50	7.75	1.25	2.75	4.48	3.47
20	42.50	7.75	1.25	1.25	4.35	4.35
21	42.50	7.75	1.25	−0.25	2.78	3.67
22	50.00	8.50	0.50	0.50	1.89	1.72
23	35.00	8.50	0.50	0.50	1.55	1.75
24	50.00	7.00	2.00	2.00	3.20	3.40
25	42.50	7.75	−0.25	1.25	0.090	0.12
26	42.50	6.25	1.25	1.25	2.98	2.67
27	42.50	7.75	1.25	1.25	4.35	4.35
28	50.00	7.00	2.00	0.50	3.35	3.22
29	50.00	7.00	0.50	2.00	1.38	1.58
30	35.00	7.00	0.50	0.50	3.10	2.21