Zuckerforschung Tulln GmbH, Tulln, Austria.
J Sci Food Agric. 2011 Aug 30;91(11):2038-44. doi: 10.1002/jsfa.4416. Epub 2011 Apr 14.
In this study the inhibition of hop beta acids on the growth of clostridia in soil-contaminated pressed sugar beet pulp silages was investigated. Hop beta acids are natural substances which display their effect at low concentrations. Fresh pressed beet pulp material was mixed with soil to artificially contaminate it with clostridia. Laboratory silos were filled with the substrate, stored at 25 °C and opened for sampling at 0, 2, 8, 15, 30, 60, and 90 days. The impact on clostridial growth during silage fermentation was monitored by determination of the pH value and dry matter content, as well as chemical analysis of the fermentation products. Throughout the experiments, the effect of a commercial silage inoculant based on lactic acid bacteria (LAB) and hop-resistant LAB were examined with and without the combination of plant-based antimicrobials.
Results indicate that in contaminated silage samples without any additives high butyric acid contents occurred due to clostridial growth. This spoilage could not be suppressed by the application of LAB, whereas the combined application of LAB and hop beta acids significantly improved silage quality, which was reflected by favourable organic acid composition (P < 0.05).
The experimental data indicate that the application of hop beta acids improves the preservation effect of LAB in suppressing clostridial growth in silages and thus demonstrates some potential for the combined use of plant-based antimicrobials and LAB.
本研究旨在考察葎草酮酸对土壤污染的糖用甜菜渣青贮中梭菌生长的抑制作用。葎草酮酸是一种天然物质，其作用浓度较低。新鲜压榨的甜菜渣与土壤混合，以人工污染其中的梭菌。实验室青贮窖装满底物，在 25°C 下储存，并在 0、2、8、15、30、60 和 90 天取样。通过测定 pH 值和干物质含量以及发酵产物的化学分析，监测青贮发酵过程中梭菌生长的影响。在整个实验过程中，研究了基于乳酸菌（LAB）和抗葎草酮酸 LAB 的商业青贮接种剂的作用，以及是否结合植物源抗菌剂。
结果表明，在没有任何添加剂的污染青贮样品中，由于梭菌的生长，丁酸含量较高。这种变质不能通过应用 LAB 来抑制，而 LAB 和葎草酮酸的联合应用显著提高了青贮质量，这反映在有利的有机酸组成上（P < 0.05）。
实验数据表明，葎草酮酸的应用提高了 LAB 抑制青贮中梭菌生长的保存效果，因此证明了植物源抗菌剂和 LAB 联合使用的潜力。
