Bacillamide, a novel algicide from the marine bacterium, Bacillus sp. SY-1, against the harmful dinoflagellate, Cochlodinium polykrikoides

Bacillamide (1) was isolated as a new algicide against the harmful dinoflagellate, Cochlodinium polykrikoides, from the marine bacterium, Bacillus sp. SY-1, and its structure was elucidated by extensive two-dimensional NMR techniques including ¹H-¹⁵N HMBC analysis and mass analysis. Bacillamide showed algicidal activity against C. polykrikoides with LC₅₀ of 3.2 μg/ml.     

海绵共附生芽孢杆菌中bacillamide C的快速分离

以一株海绵共附生芽孢杆菌发酵液的乙酸乙酯萃取物为原料,分别用硅胶吸附柱层析、离心薄层层析和半制备HPLC三种方法对其中的天然杀藻活性物质bacillamide C进行分离提纯,通过对分离过程中进样量、时间、洗脱液消耗量和分离物中bacillamide C的纯度和回收率的分析比较,对三种方法的优缺点做出综合评定,认为半制备HPLC法有成为理想的快速分离bacillamide C方法的潜力。     

Production of bioactive tryptamine derivatives by co-culture of marine Streptomyces with Bacillus mycoides

Tryptamine derivatives such as tryptamine and bacillamides were strong algicidal compounds promising in controlling harmful algae blooms, but their bioactivity and application researches were hindered by extremely low natural production rates. This study found an induced production of algicidal tryptamine derivatives by co-culture of marine Streptomyces with Bacillus mycoides, and optimised the culture method through changing important factors such as medium nutrition content, culture mode and pH value. The final established co-culture method used only 5 g yeast extracts and 5 g glycerol in 1 L 75% sea water, but got a yield of 14.9 mg/L N-acetyltryptamine, 2.8 mg/L N-propanoyltryptamine, 3.0 mg/L bacillamide A, 13.7 mg/L bacillamide B and 9.6 mg/L bacillamide C, which were all undetectable under normal culture conditions.