สำนักราชบัณฑิตยสภา

205 สมศั กดิ์ ด� ำรงค์เลิ ศ และคณะ วารสารราชบัณฑิตยสถาน ปีที่ ๓๗ ฉบับที่ ๑ ม.ค.-มี.ค. ๒๕๕๕ Reduction of different sulfonated azo dyes by whole cells of strain A5 in the presence of different concent- rations of AQDS The addition of quinoid redox me- diators resulted in an increased reduction rate for azo compounds by various bacteria (26, 29, 30, 42, 43). To demonstrate the general applicability of this system for the treatment of textile wastewaters, various sulfonated azo dyes were incubated under anaerobic condition with whole cells of Paenibacillus sp. strain A5 in the presence of different concentrations of AQDS. Thus, it was found that the addition of AQDS significantly increased the rate of decol- orization of various sulfonated azo dyes (Fig. 3). Concentration of AQDS as low as 50 µM significantly stimulated all sulfonated azo dyes reduction by cell suspensions of Paenibacillus sp. strain A5 (Fig. 3). The rate of azo dyes reduction was also dependent on the concentration of AQDS added. FIG.2 Reduction of sulfonated azo dyes by Paenibacillus sp. strain A5 in the presence or absence of AQDS. The reduction of Remazol Brilliant Orange 3R (A), Remazol Black B (B), and Remazol Brilliant Violet 5R (C).