Safety characterisation and inhibition of fungi and bacteria by a novel multiple enterocin-producing Enterococcus lactis 4CP3 strain
Safety characterisation and inhibition of fungi and bacteria by a novel multiple enterocin-producing Enterococcus lactis 4CP3 strain
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DOI：
10.1016/j.micpath.2018.03.005
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发表时间：
2018-05-01
影响因子：
3.8
通讯作者：
Ghrairi, Taoufik
中科院分区：
文献类型：
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作者：
Ben Braiek, Olfa;Cremonesi, Paola;Ghrairi, Taoufik
本研究旨在鉴定从锯缘白虾中分离到的一株潜在产细菌素乳酸菌，并对其安全性进行评价。命名为4CP 3的菌株显示出对革兰氏阳性和革兰氏阴性食源性病原体（单核细胞增生李斯特菌和铜绿假单胞菌）和一些丝状真菌（例如尼日尔曲霉A79）的抗菌活性（P < 0.05）。表型和分子生物学技术以及系统发育分析确定分离物4CP 3为乳酸肠球菌。其产生的抗微生物物质被确定为细菌素，在宽范围的pH值（2-10）和在100 ℃下加热15分钟后是稳定的。最大细菌素产量为1400 Au/ml，在30 ℃下在de Man，Rogosa和Sharpe（MRS）肉汤培养基中孵育12小时后记录。4CP 3菌株产生的细菌素对L.单核细胞增多症EGDe 107776和铜绿假单胞菌ATCC 27853。通过特异性PCR扩增，E.乳酸杆菌4CP 3能产生肠菌素A、B和P。从生虾中分离的乳酸菌。关于E. Incas 4CP 3菌株不溶血，明胶酶阴性，对万古霉素敏感，无常见抗生素耐药基因和毒力因子。因此，它可能是一种安全的天然食品防腐剂，或作为一种新的益生菌菌株在食品和饲料。
This study aims to characterise a potential bacteriocinogenic lactic acid bacterial strain isolated from a raw pink shrimp (Palaemon serratus) and evaluate its safety aspect. The strain designated as 4CP3 was noted to display antibacterial activities (P < 0.05) against Gram-positive and Gram-negative foodbome pathogens (Listeria monocytogenes and Pseudomonas aeruginosa) and some filamentous fungi (e.g. Aspergillus niger A79). Phenotypic and molecular techniques as well as phylogenetic analysis identified the isolate 4CP3 as Enterococcus lactis. Its produced antimicrobial substance was determined as a bacteriocin that was stable over a wide range of pH (2-10) and after heating at 100 degrees C for 15 min. The maximum bacteriocin production was 1400 AU/ml recorded after 12 h of incubation in de Man, Rogosa and Sharpe (MRS) broth medium at 30 degrees C. The mode of action of the bacteriocin produced by 4CP3 strain was identified as bactericidal against L. monocytogenes EGDe 107776 and P. aeruginosa ATCC 27853. By specific PCR amplifications, E. lactis 4CP3 was shown to produce the enterocins A, B and P. To our knowledge, this feature is newly described for E. lactis strain isolated from raw shrimps. Regarding safety aspect of E. Incas 4CP3, it has been demonstrated that this strain was not haemolytic, gelatinase negative, sensitive to vancomycin, and free of common antibiotic resistance genes and virulence factors. Therefore, it may be useful as a safe natural agent in preservation of foods or as a new probiotic strain in food and feed.