焦曲霉色素结构的鉴定及产色素条件的优化  

Identification of pigment structure of Aspergillus ustus and optimization of pigment production conditions

作　　者：周明辉 曾慧云 王梦倩 张雁 王占军 ZHOU Minghui;ZENG Huiyun;WANG Mengqian;ZHANG Yan;WANG Zhanjun(School of Life Sciences,Hefei Normal University,Hefei 230061,China)

机构地区：[1]合肥师范学院生命科学学院,安徽合肥230061

出　　处：《食品与发酵工业》2022年第18期191-197,共7页Food and Fermentation Industries

基　　金：安徽省高校自然研究重点项目(KJ201940728);安徽省高校自然科学基金重大项目(KJ2021ZD0113);安徽优秀人才支持计划项目(gxyq2020040)。

摘　　要：微生物源天然食用色素具有较多的优势,但目前开发不足。对分离的1株焦曲霉菌进行发酵培养,能产生丰富的棕红色色素,对其发酵液进行离心、醇沉、冷冻真空干燥处理,得到色素的粗提物。利用薄层层析与柱层析对色素粗提物进行分离纯化,以了解色素的组成特性,并获取色素滤液。通过紫外可见光谱(ultraviolet-visible spectroscopy,UV-vis)、红外光谱(infrared spectroscopy,IF)、GC-MS对色素滤液检测,以判断该色素的最大吸收峰、重要基团与化学结构。作碳氮源单因素试验,获取最适碳氮源,进而应用均匀设计法优化焦曲霉的产色素条件,以提高其产量。结果表明,焦曲霉色素是水溶性的胞外色素,极性较强,且色素组分相对单一,硅胶薄层层析与柱层析能将色素分离纯化。色素在298 nm处有最大吸收峰,色素含有吡咯吡嗪二酮与二蒽酮类2种结构的聚酮类色素,是一种新的微生物源天然色素。焦曲霉产色素的最优条件为pH 7.1、温度25.8℃、转速221.8 r/min、脱色时间128.7 h、接种量2.8 mL/150 mL、葡萄糖16 g/L、蛋白胨12 g/L。该结果为开发一种新的微生物源天然色素提供一定的研究基础。Microbial natural edible pigment has many advantages,but its potentials have not been fully tapped yet.An isolated strain of Aspergillus ustus was used to produce rich brown-red pigment by fermentation and culture,the crude extract of pigment was obtained by centrifugation,alcohol precipitation,and vacuum freezing and drying of the fermentation broth.Using thin layer chromatography(TLC)and column chromatography,the crude extract of pigment was separated and purified so as to analyze the composition of pigment and to obtain pigment filtrate.The pigment filtrate was detected by UV-vis,infrared spectroscopy and GC-MS to determine the absorption peak,important radical groups and chemical structure of the pigment.Single factor experiment was performed to obtain the optimal carbon and nitrogen sources,and then the uniform design method was applied to optimize the pigment production conditions of A.ustus to improve its yield.The results showed that A.ustus pigment was water-soluble extracellular pigment with strong polarity,and the pigment composition was relatively simple.The pigment could be separated and purified by silica gel TLC and column chromatography.A polyketone pigment containing pyrropyrazine dione and dianthracone had the absorption peak at 298 nm,suggesting a new natural pigment of microbial origin.The optimal conditions for pigment production by A.ustus were pH 7.1,25.8℃,rotational speed 221.8 r/min,decolorization time 128.7 h,inoculation amount 2.8 mL/150 mL,glucose 16 g/L,peptone 12 g/L.The results provide a basis for the development of a new microbial natural pigment.

关 键 词：焦曲霉色素 结构鉴定 优化 

分 类 号：TS264.4[轻工技术与工程—发酵工程]