Alternaria sp. MG1, a resveratrol-producing fungus: isolation, identification and optimal cultivation conditions for resveratrol production

Junling Shia,*, Qin Zenga, Yanlin Liub, Zhongli Panc,d

aCollege of Food Science and Engineering, Northwest A & F University, 28 Xinong Road, Yangling, Shaanxi Province 712100, China

bCollege of Enology, Northwest A & F University, 23 Xinong Road, Yangling, Shaanxi Province 712100, China

cProcessed Foods Research Unit, USDA-ARS-WRRC, 800 Buchanan Street, Albany, CA 94710, USA

dDepartment of Biological and Agricultural Engineering, University of California – Davis, One Shields Avenue, Davis, CA 95616, USA

*Tel: +86-29-87092486; Fax: +86-29-87092486; E-mail: (J. Shi).

Table S1 Codes and levels of the factors in the Box-Behnken design.

Independent variables / Coded symbols / Level
1 / 0 / -1
Inoculum size (%) / X1 / 7 / 5 / 3
Medium volume in flask (mL/250 mL) / X2 / 130 / 125 / 120
Rotation speed (rpm) / X3 / 110 / 100 / 90
Temperature (°C) / X4 / 31 / 28 / 25

Table S2 Box–Behnken experimental design.

Run / X1
Inoculum size (%) / X2
Medium volume in flask (mL/250 mL) / X3
Rotation speed (rpm) / X4
Temperature(°C) / Resveratrol production (µg/L)
Experimental / Predicted
1 / 3 / 125 / 110 / 28 / 223 / 222
2 / 5 / 120 / 100 / 25 / 342 / 380
3 / 5 / 130 / 100 / 25 / 278 / 287
4 / 5 / 130 / 100 / 31 / 241 / 206
5 / 7 / 125 / 100 / 31 / 204 / 250
6 / 3 / 125 / 100 / 25 / 301 / 285
7 / 7 / 130 / 100 / 28 / 332 / 338
8 / 3 / 125 / 90 / 28 / 201 / 229
9 / 3 / 120 / 100 / 28 / 232 / 206
10 / 3 / 130 / 100 / 28 / 277 / 284
11 / 5 / 130 / 90 / 28 / 186 / 183
12 / 5 / 125 / 100 / 28 / 428 / 414
13 / 7 / 125 / 110 / 28 / 399 / 358
14 / 7 / 120 / 100 / 28 / 451 / 423
15 / 5 / 120 / 100 / 31 / 127 / 120
16 / 5 / 125 / 100 / 28 / 389 / 414
17 / 3 / 125 / 100 / 31 / 108 / 115
18 / 5 / 125 / 100 / 28 / 410 / 414
19 / 5 / 125 / 100 / 28 / 431 / 414
20 / 5 / 125 / 100 / 28 / 412 / 414
21 / 7 / 125 / 90 / 28 / 346 / 365
22 / 5 / 120 / 110 / 28 / 158 / 179
23 / 7 / 125 / 100 / 25 / 423 / 421
24 / 5 / 120 / 90 / 28 / 371 / 373
25 / 5 / 125 / 90 / 25 / 343 / 318
26 / 5 / 125 / 110 / 25 / 315 / 311
27 / 5 / 125 / 90 / 31 / 167 / 147
28 / 5 / 130 / 110 / 28 / 346 / 362
29 / 5 / 125 / 110 / 31 / 131 / 140

Fig. S1 HPLC chromatogram of the standard resveratrol (A) and liquid culture of Alternaria sp. MG1 (B).

Fig. S2 Neighbor-joining phylogenetic tree using ITS sequences from Alternaria sp. strain MG1 and related fungal ITS sequences as found by nBlast searching in GenBank at NCBI. GenBank accession numbers are indicated in parentheses. The phylogenetic tree was constructed using the MEGA4.0 software after sequence alignment with ClustalX 1.8. The confidence values for individual branches were determined by bootstrap analyses (1000 replications) and maximum parsimony.