Russo Pasquale, Arena Mattia Pia, Fiocco Daniela, Capozzi Vittorio, Drider Djamel, Spano Giuseppe
Department of Science of Agriculture, Food and Environment, University of Foggia, Via Napoli 25, Foggia 71122, Italy.
Department of Clinical and Experimental Medicine, University of Foggia, Via Napoli 20, Foggia 71122, Italy.
Int J Food Microbiol. 2017 Apr 17;247:48-54. doi: 10.1016/j.ijfoodmicro.2016.04.027. Epub 2016 May 6.
Cereal-based fermented products are worldwide diffused staple food resources and cereal-based beverages represent a promising innovative field in the food market. Contamination and development of spoilage filamentous fungi can result in loss of cereal-based food products and it is a critical safety concern due to their potential ability to produce mycotoxins. Lactic Acid Bacteria (LAB) have been proposed as green strategy for the control of the moulds in the food industry due to their ability to produce antifungal metabolites. In this work, eighty-eight Lactobacillus plantarum strains were screened for their antifungal activity against Aspergillus niger, Aspergillus flavus, Fusarium culmorum, Penicillium roqueforti, Penicillium expansum, Penicillium chrysogenum, and Cladosporium spp. The overlayed method was used for a preliminary discrimination of the strains as no, mild and strong inhibitors. L. plantarum isolates that displayed broad antifungal spectrum activity were further screened based on the antifungal properties of their cell-free supernatant (CFS). CFSs from L. plantarum UFG 108 and L. plantarum UFG 121, in reason of their antifungal potential, were characterized and analyzed by HPLC. Results indicated that lactic acid was produced at high concentration during the growth phase, suggesting that this metabolic aptitude, associated with the low pH, contributed to explain the highlighted antifungal phenotype. Production of phenyllactic acid was also observed. Finally, a new oat-based beverage was obtained by fermentation with the strongest antifungal strain L. plantarum UFG 121. This product was submitted or not to a thermal stabilization and artificially contaminated with F. culmorum. Samples containing L. plantarum UFG 121 showed the best biopreservative effects, since that no differences were observed in terms of some qualitative features between not or contaminated samples with F. culmorum. Here we demonstrate, for the first time, the suitability of LAB strains for the fermentation and antifungal biopreservation of oat-based products.
以谷物为基础的发酵产品是全球广泛分布的主食资源，而谷物基饮料是食品市场中一个有前景的创新领域。丝状真菌的污染和腐败会导致谷物类食品损失，由于它们有产生霉菌毒素的潜在能力，这是一个关键的安全问题。乳酸菌（LAB）因其产生抗真菌代谢物的能力，已被提议作为食品工业中控制霉菌的绿色策略。在这项工作中，筛选了88株植物乳杆菌菌株对黑曲霉、黄曲霉、禾谷镰刀菌、罗克福特青霉、扩展青霉、产黄青霉和枝孢属的抗真菌活性。采用覆盖法对菌株进行初步区分，分为无抑制剂、轻度抑制剂和强抑制剂。对表现出广谱抗真菌活性的植物乳杆菌分离株，根据其无细胞上清液（CFS）的抗真菌特性进一步筛选。基于植物乳杆菌UFG 108和植物乳杆菌UFG 121的抗真菌潜力，对其CFS进行了HPLC表征和分析。结果表明，在生长阶段产生了高浓度的乳酸，这表明这种代谢能力与低pH值共同促成了解释突出的抗真菌表型。还观察到苯乳酸的产生。最后，用抗真菌能力最强的植物乳杆菌UFG 121发酵获得了一种新的燕麦基饮料。该产品经过或未经过热稳定处理，并人工接种禾谷镰刀菌。含有植物乳杆菌UFG 121的样品显示出最佳的生物防腐效果，因为在未接种或接种禾谷镰刀菌的样品之间，在一些质量特征方面未观察到差异。在这里，我们首次证明了乳酸菌菌株适用于燕麦基产品的发酵和抗真菌生物保存。
