이 연구는 해양 유래의 천연 항산화물질에 관한 연구로서 항산화물질 생산 해양 방선균은 제주연안 해수에서 분리되었다. 균주는 16S rRNA 염기서열, 전자현미경에 의한 형태학적, 생리, 생화학적 및 세포 지방산 분석을 기초로 동정되었다. 분리균주 ACT-1은 그람양성, 호기성, 비운동성, 기질균사체색이 red, 기중균사체 색이 gray계열 이었다. 세포지방산 분석결과 주요 지방산으로 $C_{15:0}$ anteiso (39.33%), $C_{16:1}$ cis 9 (11.96%), $C_{16:0}$ (13.08%)와 $C_{17:0}$ anteiso (10.99%)로 분석되었으며, 최종적으로 Streptomyces sp. ACT-1으로 동정되었다. Streptomyces sp. ACT-1 메탄올 추출물의 항산화활성은 DPPH (1,1-diphenyl-2-picrylhydrazyl), hydroxyl, alkyl radical 소거활성을 ESR (electron spin resonance) spectrometer를 이용하여 측정되었다. SBME-1 (Streptomyces broth methanol extract)의 DPPH 라디컬 소거활성은 $1,000{mu}g$/ml 농도에서 67%, Hydroxyl radical 소거활성은 $500{mu}g$/ml에서 84%, Alkyl radical 소거활성은 $1,000{mu}g$/ml 농도에서 71%를 보였다.
For the research of the natural antioxidant from marine sources, an antioxidant-producing marine actinomycetes was isolated from sea water in Jeju coastal area. The strain was identified based on 16S rDNA sequencing, the morphology by a method of scanning electron microscopy, physiological and biochemical characteristics and cellular fatty acid analysis. The isolated strain ACT-1 cell size was $0.5sim1.0{mu}m$ and gram positive, aerobic, nonmotile, substrate mycelium are red and gray aerial mycelium. 16S rRNA sequence analysis showed that were Gram-positive bacteria grouped on Streptomyces genus. Results of cellular fatty acid analysis showed that major cellular fatty acids were $C_{15:0}$ anteiso (39.33%), $C_{16:1}$ cis 9 (11.96%), $C_{16:0}$ (13.08%) and $C_{17:0}$ anteiso (10.99%). Finally, strain was identified Streptomyces sp. ACT-1. The antioxidant activity of methanol extract from Streptomyces sp. ACT-1 was evaluated by measuring DPPH, hydroxyl, and alkyl radical scavenging activity using an electron spin resonance (ESR) spectrometer. DPPH radical scavenging activity of SBME-1 (Streptomyces broth methanol extract) was 67% at $1,000{mu}g$/ml. Hydroxyl radical scavenging activity of SBME-1 was 84% at $500{mu}g$/ml. Alkyl radical scavenging activity of SBME-1 was 71% at $1,000{mu}g$/ml.
