다시마 물 추출액과 발효액의 항산화 및 항염증 활성

Antioxidant and Anti-inflammatory Activities of Water and the Fermentation Liquid of Sea Tangle (Saccharina japonica)

Abstract

본 연구에서는 다시마 물 추출액과 유산균(Lactobacillus brevis)으로 발효한 다시마 발효액의 이화학적 특성 및 항산화 활성과 항염증 활성에 대하여 검토하였다. 다시마 물 추출액 및 발효액의 pH는 각각 6.18과 4.16이었고, 당도는 $8.50^{\circ}Brix$와 $7.40^{\circ}Brix$였다. 다시마 물 추출액과 발효액의 주요 유리아미노산은 glutamic acid와 aspartic acid 및 alanine으로 발효에 의해 glutamic acid는 감소한 반면 GABA의 함량은 증가하였다. 다시마 물 추출액 및 발효액의 총 폴리페놀 함량은 각각 $498.29{\mu}g\;GAE/ml$와 $615.77{\mu}g\;GAE/ml$였다. DPPH radical 소거능은 농도 의존적으로 증가하였으며, 10% 농도에서의 DPPH radical 소거능은 각각 89.89%와 96.94%로 나타났다(p<0.05). 다시마 물 추출액과 발효액의 SOD 활성 또한 농도 의존적으로 증가하였으며, 다시마 발효액의 경우 물 추출액보다 유의적으로 활성이 증가하는 결과가 나타났다(p<0.05). 나아가 LPS로 유도된 RAW 264.7 대식세포를 이용하여 항염증 활성을 검토하였다. 다시마 물 추출액과 발효액의 ROS 생성은 1% 농도에서 각각 189.90% 및 174.69%를 나타내었다. 또한, 염증성 cytokines인 $TNF-{\alpha}$와 $IL-1{\beta}$의 분비량은 다시마 발효액이 물 추출액보다 유의적으로 감소하는 결과가 나타났다(p<0.05). 이상의 결과에서와 같이 다시마 추출액과 발효액은 높은 항산화 및 항염증 활성이 있는 것으로 나타났으며, 특히 발효에 의해 그 활성이 증가하여 기능성 식품소재로서 활용이 가능할 것으로 사료된다.

The study investigated the physiochemical properties and the antioxidant and anti-inflammatory activities of the sea tangle (Saccharina japonica) in a water extract before (STWE) and after (STFL) fermentation with Lactobacillus brevis. The pH values of STWE and STFL were 6.18 and 4.16, and the sugar contents were $8.50^{\circ}Brix$ and $7.40^{\circ}Brix$, respectively. The main free amino acids of STWE and STFL were glutamic acid, aspartic acid, and alanine, and the ${\gamma}$-amino butyric acid (GABA) content was increased by fermentation. The total polyphenol contents of STWE and STFL were 498.29 and 615.77 mg gallic acid equivalent (GAE)/ml, respectively. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities of STWE and STFL were markedly increased in a dose-dependent manner, and revealed about 89.89% and 96.94% activities, respectively, at 10% concentration (p<0.05). The superoxide dismutase (SOD) activities of STWE and STFL were also markedly increased in a dose-dependent manner, and the activity of STFL was significantly increased when compared with STWE (p<0.05). The anti-inflammatory activity was examined in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. STWE and STFL decreased the production of reactive oxygen species (ROS), which had levels of about 189.90% and 174.69% at 1% concentration, respectively (p<0.05). The contents of pro-inflammatory cytokines, such as tumor necrosis factor-alpha ($TNF-{\alpha}$) and interleukin-6 (IL-6), were decreased more by addition of STFL than by addition of STWE. The STWE and STFL showed high antioxidant and anti-inflammatory activity, and these activities were increased by fermentation. Therefore, sea tangle extracts can be used as functional food materials.

Fig. 1. DPPH radical scavenging activity of sea tangle water extract and fermentation liquid.

Fig. 2. Superoxide dismutase (SOD) activity of sea tangle water extract and fermentation liquid.

Fig. 3. ABTS radical scavenging activity of sea tangle water extract and fermentation liquid.

Fig. 4. Effects of sea tangle water extract and fermentation liquid on cell cytotoxicity in bacterial LPS-stimulated RAW 264.7 cells.

Fig. 5. Effect of sea tangle water extract and fermentation liquid on intracellular ROS level in LPS-treated RAW 264.7 cells.

Fig. 6. Effects of sea tangle water extract and fermentation liquid on NO synthesis in bacterial LPS-stimulated RAW264.7 cells.

Fig. 7. Effects of sea tangle water extract and fermentation liquid on the production of TNF- α in RAW 264.7 cells.

Fig. 8. Effects of sea tangle water extract and fermentation liquid on the production of IL-6 in RAW 264.7 cells.

Table 1. pH and sugar content (°Brix) of sea tangle water extract and fermentation liquid

Table 2. Free amino acid contents of sea tangle water extract and fermentation liquid

Table 3. Total polyphenol contents of sea tangle water extract and fermentation liquid