Major trypsin like-serine proteinases from albacore tuna (Thunnus alalunga) spleen: Biochemical characterization and the effect of extraction media

作者：Poonsin Tanchanok; Sripokar Pakteera; Benjakul Soottawat; Simpson Benjamin K; Visessanguan Wonnop; Klomklao Sappasith^*

来源：Journal of Food Biochemistry, 2017, 41(2): UNSP e12323.

DOI：10.1111/jfbc.12323

• extraction
• characterization
• proteinase
• viscera
• trypsin

This investigation aimed to characterize the proteinases and to study the effect of extraction media on proteinases recovery from albacore tuna spleen. Optimal activity of splenic extract was at pH 9.5 and 55 degrees C. The enzyme was stable in a wide pH range of 6.0-10.0 but unstable at the temperatures greater than 50 degrees C for 30-120 min. The proteolytic activity was strongly inhibited by soybean trypsin inhibitor, N-ethylmaleimide, phenylmethylsulfonyl fluoride (PMSF), and N-p-tosyl-L-lysine chloromethyl ketone (TLCK) and continuously decreased with increasing NaCl concentration. The molecular weights of spleen proteinases were 22, 24, 31, and 34 kDa based on the proteinase activity of zones separated by electrophoresis. Spleen powder isolation with 50 mM sodium phosphate buffer, pH 7.0 containing 1.25 M NaCl and 2% (v/v) Brij 35 gave a higher recovery of proteinase activity than other extractants tested (p<.05). Therefore, the major proteinases from spleen of albacore tuna were trypsin-like serine proteinases.
Practical applicationsExtraction and recovery of proteinases from albacore tuna spleen contribute significantly to reduce the local pollution problem and increase valuable products from albacore tuna processing wastes. Moreover, the characteristics of the enzyme obtained can be utilized in the food, detergent, pharmaceutical, leather and silk industries.

• 出版日期2017-4