M. pilosus를 액침배양하여 얻은 균사체의 ethanol 추출물(MEM)과 그 배양여액(CFM)의 monacolin K 및 citrinin 함량과 항산화 및 항균활성을 조사하였다. MEM과 CFM 동결건조 분말의 수율은 4.02% 및 3.35% 이었다. 색소함량($OD_{500}$)은 MEM (0.79)이 CFM (0.63)보다 25%가 높았으나 시판홍국미 에탄올추출물(EERB) 0.87 보다는 낮았으며 L*값, a*값, b*값 및 hue angle의 결과와 일치하였다. Total monacolin K의 함량은 MEM (24.91 mg%)이 CFM (1.27mg%) 및 EERB (15.03 mg%)에 비하여 높았으나 활성형 monacolin K의 함량은 EERB (5.48 mg%), MEM (3.35 mg%), CFM (0.40 mg%)으로 EERB가 높았다. Citrinin은 모든 시료에서 검출되지 않았다. Total polyphenol 함량은 MEM (4.68%, w/w), CFM (4.29%, w/w), EERB (3.70%, w/w)로 MEM과 CFM에서 높았다. 그러나 total flavonoid 함량은 EERB(4.46%, w/w), MEM(0.64%, w/w), CFM (0.66%, w/w)으로 EERB에서 높았다. 총 항산화능은 CFM이 3.51%(w/w)로 MEM (2.74%, w/w) 및 EERB (1.69%, w/w)보다 높았다. 1%에서의 전자공여능은 MEM (72.25%), CFM (86.20%), BHT (72.25%), EERB (44.82%)로 MEM과 CFM이 BHT보다 높거나 유사하였으며, 환원력도 비슷한 결과를 나타내었다. SOD 유사활성은 MEM (39.85%) > BHT (37.68%) > EERB (26.70%) > CFM (21.35%)순이었으며 아질산염소거능은 CFM (79.42%) > EERB (74.37%) > MEM (62.78%) > BHT (48.46%) 이었다. TBARS(%)는 MEM이 BHT보다 다소 낮았으나 CFM과 EERB보다 높았다. B. brevis와E. coli에 대한 항균성은 CFM이 MEM보다 높았으며 B. subtilis, L. monocytogenes, S. aureus, S. epidermidis, S. enteritidis에 대한 항균성은 MEM이 CFM보다 높았으나 EERB 및 BHT 경우보다는 낮았다.
We evaluated the nutritional value of a Monascus pilosus mycelial ethanolic extract (MEM) and culture filtrate (CFM) by determining the contents of monacolin K and citrinin, and by measuring antioxidant and antimicrobial activities. The yields of freeze-dried MEM and CFM powder were 4.02% and 3.35% of wet weight, respectively. Pigment content ($OD_{500}$ value) of MEM (0.79) and CFM (0.63) were lower than those of commercial rice beni-koji ethanolic extracts (EERB) (0.87), but were in good agreement with the L*, a*, and b* values and the hue angles of the products. The total monacolin K content of MEM (24.91 mg%) was higher than those of CFM (1.27 mg%) and EERB (14.65 mg%). However, the active monacolin K content of EERB (5.48 mg%) was higher than those of MEM (3.35 mg%) and CFM (0.4 mg%). Citrinin was not detected in any sample. The total polyphenol content of MEM (4.68%, w/w) was similar to that of CFM (4.29%, w/w), thus 13.75.20.94% higher than that of EERB. The total flavonoid content of EERB was 6.8.7.0-fold higher than those of MEM (0.64%, w/w) and CFM (0.66%, w/w). The total antioxidant capacity of CFM (3.51%, w/w) was 1.62.2.08-fold higher than those of MEM (2.74%, w/w) and EERB (1.69%, w/w). The electron-donating capacities of 1% (w/v) solutions of CFM, MEM, BHT, and EERB were 86.20%, 77.25%, 77.25%, and 44.82%, respectively, and the corresponding reducing powers ($OD_{700}$ values) were 2.1, 2.4, 1.1, and 1.6, respectively. SOD(superoxide dismutase)-like activities were in the order MEM (39.85%) > BHT (37.68%) > EERB (26.70%) > CFM (21.5%). Although the TBARS (% value) of MEM was a little lower than that of BHT, it was higher than those of CFM and EERB. The antibacterial activities of CFM acting on Bacillus brevis and Escherichia coli were somewhat higher than those of MEM, whereas the activities of MEM on Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Staphylococcus epidermidis, and Salmonella enteritidis were higher than those of CFM. However, the antibacterial activities of MEM and CFM were less than those of EERB and BHT. In conclusion, although further studies are needed, we offer experimental evidence that the by-products of M. pilosus MEM and CFM contain significant antioxidant and antimicrobial activities that may be useful in the development of healthy foods.
