黑豆麴之抗致突變性及其作用機制

Abstract

本研究以東方發酵食品常用之五種菌酛： Aspergillus awamori、Aspergillus oryzae BCRC30222、Aspergillus sojae BCRC30103、Rhizopus azygosporus BCRC 31158 及 Rhizopus sp. No. 2 製備黑豆麴，探討發酵黑豆麴總酚類化合物、總花青素及對 4-nitroquinoline-N-oxide (4-NQO) and Benzo[a]pyrene (B[a]P) 抗致突變活性，接著進一步比較不同培養溫度與培養時間製備黑豆麴對總酚類化合物、總花青素及抗致突變活性之影響，最後則針對黑豆麴之抗致突變機制進行研究討論。 實驗結果顯示經過發酵後之黑豆麴其總酚類化合物及總花青素含量皆提高，且黑豆麴，無論使用何種菌酛，其甲醇萃取物之抗致突變活性也高於未發酵之黑豆，然而黑豆麴之抗致突變性因發酵菌酛不同而有所差異。其中以A. awamori所發酵之黑豆對4-NQO及B[a]P具有最高之抗致突變活性，且總酚類化合物與總花青素含量也最高。 利用A. awamori進行培養溫度 (25℃、30℃、35℃) 及培養時間 (1~5天) 試驗，發現在30℃培養溫度下所製備的黑豆麴其總酚類化合物及總花青素含量最高，抗致突變活性也最佳。當發酵時間為3天時，對於提升A. awamori黑豆麴之總酚類化合物、總花青素含量及抗致突變活性有最佳之效果。 探討A. awamori所發酵之黑豆麴對4-NQO及B[a]P所呈現之抗致突變作用顯示，其活性源自於生物抗致突變、去致突變性及Blocking effect之效應。

In the present study, black soybean kojis were first prepared with Aspergillus awamori、Aspergillus oryzae BCRC30222、Aspergillus sojae BCRC30103、Rhizopus azygosporus BCRC 31158 and Rhizopus sp. No. 2, which are commonly employed as starter organism for production of oriental fermented foods. Changes of tatol phenolic and total anthocyanin contents as well as antimutagenic activity against 4- nitroquinoline- N- oxide (4-NQO) and Benzo[a]pyrene (B[a]P) of black soybean due to fermentation were examined. Besides, effect of cultivation temperature and fermentation period on the tatol phenolic, total anthocyanin content and antimutagenic activity of the A. awamori-prepared black soybean koji were also examined. Additionally, the mechanism of antimutagenic activity of the A. awamori-prepared black soybean koji was also investigated. The result showed tatol phenolic and total anthocyanin contents of black soybean were increased after fermentation. The methanolic extracts of black soybean kojis, regardless of starters used, exhibited a higher antimutagenic activity than that the non-fermented black soybean. While antimutagenicity of black soybean koji varied with the starter used. Among the various kojis examined, koji prepared with A. awamori showed the highest antimutagenic effect against 4-NQO and B[a]P. It also showed the highest tatol phenolic and total anthocyanin contents. In further studies, black soybean koji was prepared with A. awamori at different temperatures (25℃, 30℃ and 35℃) and various fermentation periods (1-5 days). It was found that the methanolic extract of A. awamori koji prepared at 30℃ for 3 days exhibited the highest antimutagenic activity and the highest total contents of phenolic and anthocyanin. Study on the possible antimutagenic mechanism, revealed that the bio-antimutagenic, desmutagenic and blocking effect all contributed to the antimutagenicity of A. awamori-koji against 4-NQO and B[a]P.