As an environmentally friendly and efficient method, successive two-step fermentation has been applied for extracting chitin from shrimp shells. To screen out the microorganisms for fermentation, a protease-producing strain, Exiguobacterium profundum, and a lactic acid-producing strain, Lactobacillus acidophilus, were isolated from the traditional fermented shrimp paste. Chitin was extracted by successive two-step fermentation with these two strains, and 85.9 ± 1.2% of protein and 95 ± 3% of minerals were removed. The recovery and yield of chitin were 47.82 and 16.32%, respectively. Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy (SEM) were used to characterize the chitin. The crystallinity index was 54.37%, and the degree of deacetylation was 3.67%, which was lower than that of chitin extracted by the chemical method. These results indicated that successive two-step fermentation using these two bacterial strains could be applied to extract chitin. This work provides a suitable strategy for developing an effective method to extract chitin by microbial fermentation.

作为一种环保高效的方法，连续两步发酵已被应用于从虾壳中提取几丁质。筛选出用于发酵的微生物，一种产生蛋白酶的菌株，深层微小杆菌和乳酸产生菌株， 嗜酸乳杆菌，是从传统的发酵虾酱中分离出来的。用这两种菌株连续两步发酵提取甲壳素，去除了85.9±1.2%的蛋白质和95±3%的矿物质。甲壳素的回收率和收率分别为47.82%和16.32%。傅里叶变换红外光谱、X 射线衍射和扫描电子显微镜 (SEM) 用于表征几丁质。结晶度指数为54.37%，脱乙酰度为3.67%，低于化学法提取的甲壳素。这些结果表明，使用这两种菌株的连续两步发酵可用于提取几丁质。这项工作为开发一种通过微生物发酵提取几丁质的有效方法提供了合适的策略。