*3.4. SDS-PAGE*

SDS-PAGE was conducted as described in our earlier study [2]. Briefly, 300 μL of 2 μg/μL *T. flavidus* extract was mixed with 100 μL of loading buffer, incubated in boiling water for 3 min, cooled at room temperature, and then centrifuged at 8500× *g* for 5 min. Supernatant (5 μL/lane) was characterized by a polyacrylamide gel (4% stacking and 8% running) on a mini vertical electrophoresis system (Bio-Rad Laboratories, US). After electrophoresis, the gel was incubated in fixing solution (methanol:acetic acid:water, 50:10:40) for 30 min, stained by 0.1% Coomassie brilliant blue for 30 min, and then rinsed by 30% methanol containing 10% acetic acid for 30 min. Contents of the collagen subunits were estimated by Quantity One 4.6.0 (Bio-Rad Laboratories, US).
