Preparation of Soluble Silk Peptides by Food-grade Proteinases

효소 분해에 의한 가용성 실크 펩타이드의 제조

  • 하재석 (한국생명공학연구원 시스템미생물연구센터) ;
  • 송재준 (한국생명공학연구원 시스템미생물연구센터) ;
  • 조형권 ((유)한풍제약) ;
  • 이승구 (한국생명공학연구원 시스템미생물연구센터)
  • Published : 2006.06.01

Abstract

Enzymatic hydrolysis of silk fibers were investigated for the preparation of soluble silk peptides by ten food-grade proteases from Bacillus, Aspergilius, and plant sources. Silk fibers were dissolved for 1 hr in a 2:1 cosolvent (50% $CaCl_2$: ethanol) by heating at $90^{\circ}C$. The silk solution was filtered to remove Impurity particles and desalted for 50 hours by a dialysis process to remove the used cosolvent. When the silk hydrolysis was performed at $45^{\circ}C$ for 2 hours, most proteases from Bacillus and Aspergillus generated large amounts of insoluble aggregates. On the contrary, proteases from plant sources produced much less aggregates during prolonged incubations and also exhibited high hydrolysis activities. In regards of the solubility and broad molecular sizes of produced silk peptides, Bromelain was finally selected and applied for the enzymatic hydrolysis of silk fibers.

천연 단백질인 실크를 가수분해하여, 건강기능성 식품 등에 다양하게 활용될 수 있는 가용성 실크 펩타이드를 생산하는 효소공학적 연구를 수행하였다. 효소는 Bacillus, Aspergillus, 파파야, 파인애플 등으로부터 유래하는 10종의 프로티아제를 사용하였으며,가수분해 효율을 높이기 위하여 생 실크를 $CaCl_2$- 에탄올 공용액에 녹인 가용화된 실크를 제조하였고, 이를 상온 중성의 조건에서 50시간 동안 투석하여 효소반응을 위한 기질로 사용하였다. 효소반응은 37, pH 7.0에서 수행하였으며, 파인애플 유래 프로티아제인 Bromelain과 Bacillus유래 효소인 Alcalase가 실크의 가수분해에 적합한 것으로 확인되었다. 특히 파인애플 유래의 Bromelain은 가수분해 도중 불용성 침전물의 형성으로 인한 생산 수율의 감소가 가장 적어 가용성 실크 펩타이드의 제조에 적합하였고, 분자량 분포에 있어서도 보다 다양한 것으로 확인되었다.

Keywords

References

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