Production and characterization of yeasts grown on media composed of spruce-derived sugars and protein hydrolysates from chicken by-products

Table 1 Data for growth of C. jadinii, W. anomalus, B. adeninivorans and Thermosacc^® Dry grown in 2.5 L benchtop fermenters

Medium	C. jadinii		W. anomalus		B. adeninivorans		Thermosacc^® Dry
Medium	YP + G	CH + B	YP + G	CH + B	YP + G	CH + B	YP + G	CH + B
Time (h)	20	20	20	20	20	18	22	20
CDW (g/L)	24.1 ± 4.3	30.6 ± 0.5	28.0 ± 3.9	36.1 ± 0.1	39.8 ± 1.6	54.5 ± 1.4	22.5 ± 0.5	27.1 ± 3.4
Max. growth rate (h⁻¹)	0.4 ± 0.1	0.3 ± 0.0	0.6 ± 0.1	0.4 ± 0.0	0.6 ± 0.1	0.4 ± 0.1	0.5 ± 0.0	0.2 ± 0.1
Protein (%)	53.3 ± 0.9	57.4 ± 0.1	55.2 ± 2.5	50.5 ± 0.0	49.5 ± 0.0	51.8 ± 3.3	47.7 ± 4.1	54.1 ± 1.2
Protein (g/L)	12.8 ± 2.1	17.6 ± 0.3	15.4 ± 1.5	18.2 ± 0.0	19.7 ± 1.2	28.2 ± 1.1	10.7 ± 0.6	14.7 ± 2.1
Y_X/sugars		0.49 ± 0.01		0.58 ± 0.01		0.87 ± 0.02		0.42 ± 0.08
Y_P/sugars		0.28 ± 0.00		0.29 ± 0.00		0.45 ± 0.02		0.23 ± 0.05
Y_X/glucose	0.46 ± 0.09	0.65 ± 0.01	0.52 ± 0.06	0.77 ± 0.01	0.76 ± 0.05	1.15 ± 0.03	0.42 ± 0.01	0.55 ± 0.10
Y_P/glucose	0.24 ± 0.04	0.37 ± 0.01	0.28 ± 0.02	0.39 ± 0.00	0.38 ± 0.03	0.60 ± 0.02	0.20 ± 0.01	0.30 ± 0.06

The media used were YP + G or CH + B, and the start volume of the fermentation was 1.5 L. The media contained 5.86 g/L Kjeldahl nitrogen (36.6 g/L protein) and approximately 50 g/L glucose (see t = 0 point in Fig. 2, right panels; note that for B, 50 g/L glucose corresponds to 66.0 g/L total sugars; see Additional file 1: Table S1). The data shown are for the time point (indicated in the Table) at which the concentration of yeast protein (g/L) was the highest. Data for 24 h time points appear in Table 2. Y values refer to yields of CDW (X) or protein (P) per gram of consumed glucose, as measured (right panels in Fig. 2) or per gram of total sugar, as calculated from Additional file 1: Table S1 (for B only). Values are mean ± SD (n = 2)

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