Ferrochio Laura V, Cendoya Eugenia, Zachetti Vanessa G L, Farnochi Maria C, Massad Walter, Ramirez Maria L
Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas Fco-Qcas y Naturales, Universidad Nacional de Río Cuarto, Ruta 36 Km 601, 5800 Río Cuarto, Córdoba, Argentina.
Departamento de Química, Facultad de Ciencias Exactas Fco-Qcas y Naturales, Universidad Nacional de Río Cuarto, Ruta 36 Km 601, 5800 Río Cuarto, Córdoba, Argentina.
Int J Food Microbiol. 2014 Aug 18;185:51-6. doi: 10.1016/j.ijfoodmicro.2014.05.011. Epub 2014 May 22.
The objectives of the present study were to determine the in vitro efficacy of chitosan (0.5, 1.0, 2.0 and 3.0mg/mL) under different water availabilities (0.995, 0.99, 0.98, 0.96 and 0.93) at 25°C on lag phase, growth rate and fumonisin production by isolates of Fusarium verticillioides and Fusarium proliferatum. The presence of chitosan affected growth and fumonisin production, and this effect was dependent on the dose and aW treatment used. The presence of chitosan increased the lag phase, and reduced the growth rate of both Fusarium species significantly at all concentrations used, especially at 0.93 aW. Also, significant reduction of fumonisin production was observed in both Fusarium species at all conditions assayed. The present study has shown the combined effects of chitosan and aW on growth and fumonisin production by the two most important Fusarium species present on maize. Low molecular weight (Mw) chitosan with more than 70% of degree of deacetylation (DD) at 0.5mg/mL was able to significantly reduce growth rate and fumonisin production on maize-based media, with maximum levels of reduction in both parameters obtained at the highest doses used. As fumonisins are unavoidable contaminants in food and feed chains, their presence needs to be reduced to minimize their effects on human and animal health and to diminish the annual market loss through rejected maize. In this scenario post-harvest use of chitosan could be an important alternative treatment.
本研究的目的是确定壳聚糖（0.5、1.0、2.0和3.0mg/mL）在25°C下不同水分可利用性（0.995、0.99、0.98、0.96和0.93）条件下对轮枝镰孢菌和层出镰孢菌分离株的延滞期、生长速率及伏马菌素产生的体外效果。壳聚糖的存在影响生长和伏马菌素产生，且这种影响取决于所使用的剂量和水分活度处理。壳聚糖的存在延长了延滞期，并在所有使用浓度下显著降低了两种镰孢菌的生长速率，尤其是在水分活度为0.93时。此外，在所有检测条件下，两种镰孢菌的伏马菌素产生均显著减少。本研究显示了壳聚糖和水分活度对玉米上存在的两种最重要镰孢菌的生长和伏马菌素产生的联合作用。低分子量（Mw）、脱乙酰度（DD）超过70%的壳聚糖在0.5mg/mL时能够显著降低基于玉米的培养基上的生长速率和伏马菌素产生，在使用的最高剂量下这两个参数的降低水平达到最大值。由于伏马菌素是食品和饲料链中不可避免的污染物，需要减少它们的存在以尽量降低其对人类和动物健康的影响，并减少因拒收玉米导致的年度市场损失。在这种情况下，收获后使用壳聚糖可能是一种重要的替代处理方法。
