解淀粉芽孢杆菌YA289降解虾头蛋白的发酵工艺优化

Optimization of the Fermentation Conditions for Degradation of Shrimp Head Proteins by Bacillus amyloliquefaciens YA289

摘要:

为促进南美白对虾虾头副产物中蛋白质的高值化利用，同时减轻发酵过程中的氨臭问题，该研究用北海红树林中筛选得到的一株解淀粉芽孢杆菌YA289对南美白对虾的虾头进行液态发酵。分别以多肽、氨基酸态氮和氨态氮的质量浓度为指标，利用单因素试验、Plackett-Burman试验和Box-Behnken试验进行发酵工艺的优化。优化后的工艺条件为葡萄糖添加量5 g/L，NaCl添加量 5 g/L，料液比1:8 (g/100 mL)，接种量5wt%，pH值6，转速180 r/min，温度34 ℃，时间44 h，在此条件下，虾头蛋白质降解产物中的多肽质量浓度可达16.35 mg/mL，比优化前提高了2.7倍。该试验表明解淀粉芽孢杆菌YA289既对南美白对虾虾头副产物中蛋白质起到良好的降解效果，又可以减轻发酵过程中氨态氮的释放，为虾头副产物蛋白质资源和解淀粉芽孢杆菌YA289更好的开发利用提供了试验基础。

Abstract:

In order to promote the utilization of the high-value proteins in Penaeus vannamei head byproducts and to reduce the ammonia odor produced during their fermentation. A strain of Bacillus amyloliquefaciens YA289 was identified in a screen of samples collected from a mangrove forest in Beihai. This strain was used for liquid fermentation of the Penaeus vannamei heads. The polypeptide, amino acid nitrogen, and ammonia nitrogen contents of the supernatant were analyzed as indexes. The single factor test, Plackett-Burman test, and Box-Behnken test were performed to optimize the fermentation conditions, which were as follows: 5 g/L glucose, 5 g/L NaCl, a solid-to-liquid ratio of 1:8 (g/100 mL), 5wt% starter culture, pH value 6, a rotational speed of 180 r/min, 34 ℃, and 44 h. Under these conditions, the polypeptide content in the product of shrimp head fermentation was 16.35 mg/mL, which was 2.7 times higher than that before optimization. Bacillus amyloliquefaciens YA289 had a good degradation effect on the proteins in Penaeus vannamei heads and less ammonia nitrogen was released during fermentation. These findings provide an experimental basis to better utilize the protein resources from Penaeus vannamei heads and for the development and utilization of Bacillus amyloliquefaciens YA289.