Department of Applied Microbiology and Biotechnology, Yeungnam University, Gyeongsan, Korea.
Lett Appl Microbiol. 2013 Jul;57(1):69-76. doi: 10.1111/lam.12077. Epub 2013 Apr 29.
Korean kimchi is known for its myriad of lactic acid bacteria (LAB) with diverse bioactive compounds. This study was undertaken to isolate an efficient antifungal LAB strain among the isolated kimchi LABs. One thousand and four hundred LABs isolated from different kimchi samples were initially screened against Aspergillus niger. The strain exhibiting the highest antifungal activity was identified as Lactobacillus plantarum YML007 by 16S rRNA sequencing and biochemical assays using API 50 CHL kit. Lact. plantarum YML007 was further screened against Aspergillus oryzae, Aspergillus flavus, Fusarium oxysporum and other pathogenic bacteria. The morphological changes during the inhibition were assessed by scanning electron microscopy. Preliminary studies on the antifungal compound demonstrated its proteinaceous nature with a molecular weight of 1256·617 Da, analysed by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF). The biopreservative activity of Lact. plantarum YML007 was evaluated using dried soybeans. Spores of A. niger were observed in the negative control after 15 days of incubation. However, fungal growth was not observed in the soybeans treated with fivefold concentrated cell-free supernatant of Lact. plantarum YML007. The broad activity of Lact. plantarum YML007 against various food spoilage moulds and bacteria suggests its scope as a food preservative.
After screening 1400 kimchi bacterial isolates, strain Lactobacillus plantarum YML007 was selected with strong antifungal activity against various foodborne pathogens. From the preliminary studies, it was found that the bioactive compound is a low molecular weight novel protein of 1256·617 Da. Biopreservative potential of Lact. plantarum YML007 was demonstrated on soybean grains, and the results point out YML007 as a potent biopreservative having broad antimicrobial activity against various foodborne pathogens.
韩国泡菜以其拥有多种具有生物活性化合物的乳酸菌（LAB）而闻名。本研究旨在从分离的泡菜 LAB 中分离出一种具有高效抗真菌活性的 LAB 菌株。最初从不同的泡菜样本中分离出 1400 株 LAB 对黑曲霉进行了筛选。通过 16S rRNA 测序和 API 50CHL 试剂盒生化分析，发现具有最高抗真菌活性的菌株被鉴定为植物乳杆菌 YML007。植物乳杆菌 YML007 进一步筛选了米曲霉、黄曲霉、尖孢镰刀菌和其他病原菌。通过扫描电子显微镜评估抑制过程中的形态变化。通过基质辅助激光解吸电离飞行时间质谱（MALDI-TOF）分析，初步研究了抗真菌化合物的蛋白质性质，其分子量为 1256.617Da。植物乳杆菌 YML007 的生物防腐剂活性通过干大豆进行了评估。在孵育 15 天后，阴性对照中观察到黑曲霉孢子。然而，在经五倍浓缩的植物乳杆菌 YML007 无细胞上清液处理的大豆中未观察到真菌生长。植物乳杆菌 YML007 对各种食品腐败霉菌和细菌的广泛活性表明其作为食品防腐剂的范围。
在筛选了 1400 株泡菜细菌分离株后，选择了具有强抗真菌活性的植物乳杆菌 YML007 株，对各种食源性病原体均有效。从初步研究中发现，生物活性化合物是一种分子量为 1256.617Da 的新型低分子量蛋白质。植物乳杆菌 YML007 在大豆颗粒上的生物保鲜潜力得到了证明，结果表明 YML007 作为一种具有广泛抗菌活性的有效生物防腐剂，对各种食源性病原体均有效。
