Ankara Food Control Laboratory Directorate, Republic of Turkey Ministry of Agriculture and Forestry, Ankara, Turkey.
Department of Food Engineering, Engineering Faculty, Giresun University, Giresun, Turkey.
Curr Microbiol. 2022 Apr 9;79(5):148. doi: 10.1007/s00284-022-02839-z.
The aim of this research was to investigate the antifungal potential of lactic acid bacteria (LAB) isolated from Turkish spontaneous sourdough collected in summer and winter seasons from 25 different small bakeries in Trabzon, Giresun, Ordu, and Samsun. Lactic acid bacteria (933 isolates) were screened for inhibition of three common food spoilage molds (Aspergillus flavus, Aspergillus niger, and Penicillium expansum). Eight LAB isolates identified as Weissella cibaria 908, Lactiplantibacillus plantarum subsp. plantarum 2114, Leuconostoc pseudomesenteroides 2619, L. plantarum subsp. plantarum 2702, Fructilactobacillus sanfranciscensis 2709, Levilactobacillus brevis 2216Y, L. pentosus Y118, and L. plantarum subsp. plantarum Y201 by 16 S rRNA sequencing, which were found to have high antifungal activity against all the test molds. The antifungal activity of cell free supernatants from LAB isolates was not altered after thermal treatment and proteolytic enzyme proteinase K. The cell free supernatants obtained from LAB showed a high antifungal effect against molds with inhibition zone diameter up to 20 mm at pH 3.0, but no inhibitory activity was determined after pH neutralization. Moreover, all cell free suspension samples were able to maintain their efficacy up to a 1:4 dilution. The antifungal activity of supernatants was mostly related to organic acid content, especially lactic acid ranged from 4.33 to 8.41 g/L. The results indicated that eight bacterial isolates obtained from spontaneous Turkish sourdough could constitute biopreservative cultures, which may be used in food industry.
本研究旨在调查从土耳其夏季和冬季 25 家不同小型面包店采集的自发酸面团中分离出的乳酸菌（LAB）的抗真菌潜力。筛选了 933 株乳酸菌，以抑制三种常见的食品腐败霉菌（黄曲霉、黑曲霉和扩展青霉）。通过 16S rRNA 测序，将 8 株 LAB 分离株鉴定为 Weissella cibaria 908、Lactiplantibacillus plantarum subsp. plantarum 2114、Leuconostoc pseudomesenteroides 2619、L. plantarum subsp. plantarum 2702、Fructilactobacillus sanfranciscensis 2709、Levilactobacillus brevis 2216Y、L. pentosus Y118 和 L. plantarum subsp. plantarum Y201，它们对所有测试霉菌均表现出较高的抗真菌活性。经热处理和蛋白酶蛋白水解酶处理后，LAB 分离株的无细胞上清液的抗真菌活性并未改变。从 LAB 获得的无细胞上清液对霉菌表现出很高的抗真菌作用，在 pH3.0 时抑制圈直径可达 20mm，但在 pH 中和后则没有抑制活性。此外，所有无细胞悬浮液样本在 1:4 稀释后仍能保持其功效。上清液的抗真菌活性主要与有机酸含量有关，特别是乳酸含量为 4.33-8.41g/L。结果表明，从自发土耳其酸面团中获得的 8 株细菌分离株可能构成生物防腐剂培养物，可用于食品工业。
