Microbial Resources Division, Institute of Bioresources and Sustainable Development, Takyelpat Institutional Area, Imphal-795001, Manipur, India.
Int J Food Microbiol. 2010 Sep 30;143(1-2):1-8. doi: 10.1016/j.ijfoodmicro.2010.07.008. Epub 2010 Jul 15.
Soidon is a non-salted acidic fermented food prepared from the succulent bamboo shoot tip of Schizostachyum capitatum Munro by using a traditional liquid starter called "soidon mahi" in Manipur state of India. In this study, 163 bacterial isolates associated with this starter samples were identified and their population distribution was investigated by amplified ribosomal DNA restriction analysis (ARDRA), 16S rDNA sequencing and randomly amplified polymorphic DNA (RAPD) analysis. This acidic starter (pH 4.5+/-0.15) was dominated by a characteristic association of Bacillus and lactic acid bacteria (LAB) together. The population distribution of dominant species were Bacillus subtilis 29.3%, Bacillus cereus 35.7%, Bacillus pumilus 2.6%, Lactobacillus brevis 9.6%, Lactobacillus plantarum 5.1%, Carnobacterium sp. 11.9%, Enterococcus faecium 1.2% and Pseudomonas fluorescens 4.6%. Alarming population load (10(6)-10(7)cfu/ml) of B. cereus in 87% of starter samples studied should raise concern regarding biosafety of soidon consumption. PCR amplification of 16S-23S rDNA intergenic transcribed spacer (ITS) region and ITS-RFLP profiles revealed a high diversity with eight subgroups in B. subtilis, five subgroups in B. cereus and three subgroups in L. brevis isolates. The most abundant B. subtilis subgroup IB.1 distributed in most of the samples showed very less clonal variability during RAPD analysis. The molecular methods used in this study identified the dominant strains of Bacillus and LAB distributed in most of the starter samples. These dominant strains of B. subtilis, L. brevis and L. plantarum would allow for developing a defined starter culture for the production of quality soidon.
梭冬是一种非腌制的酸性发酵食品，由印度曼尼普尔邦的一种名为“梭冬玛希”的液体发酵剂，用箭竹笋尖制成。在这项研究中，对与这种发酵剂相关的 163 个细菌分离株进行了鉴定，并通过扩增核糖体 DNA 限制性分析（ARDRA）、16S rDNA 测序和随机扩增多态性 DNA（RAPD）分析来研究其种群分布。这种酸性发酵剂（pH4.5+/-0.15）主要由特征性的芽孢杆菌和乳酸菌（LAB）组成。优势种的种群分布为：枯草芽孢杆菌 29.3%、蜡样芽孢杆菌 35.7%、短小芽孢杆菌 2.6%、短乳杆菌 9.6%、植物乳杆菌 5.1%、肉杆菌 11.9%、屎肠球菌 1.2%和荧光假单胞菌 4.6%。在研究的 87%的发酵剂样品中，蜡样芽孢杆菌的种群负荷（10(6)-10(7)cfu/ml）令人担忧，这应该引起对梭冬食用生物安全性的关注。16S-23S rDNA 基因间隔区（ITS）和 ITS-RFLP 图谱的 PCR 扩增显示，枯草芽孢杆菌有 8 个亚群、蜡样芽孢杆菌有 5 个亚群、短乳杆菌有 3 个亚群，具有高度多样性。最丰富的枯草芽孢杆菌亚群 IB.1 分布在大多数样品中，在 RAPD 分析中表现出很少的克隆变异性。本研究中使用的分子方法鉴定了分布在大多数发酵剂样品中的芽孢杆菌和 LAB 的优势菌株。这些优势菌株枯草芽孢杆菌、短乳杆菌和植物乳杆菌可以用于开发梭冬的质量控制发酵剂。
