Department of Food Science and Biotechnology of Animal Resources, Konkuk University, Seoul 05029, Republic of Korea.
J Microbiol Biotechnol. 2019 Aug 28;29(8):1177-1183. doi: 10.1041/jmb.1905.05022.
Grapefruit seed extract (GSE) is a safe and effective preservative that is used widely in the food industry. However, there are few studies addressing the anti-biofilm effect of GSE. In this study, the anti-biofilm effect of GSE was investigated against biofilm-forming strains of and . The GSE minimum inhibitory concentration (MIC) for and were 25 μg/ml and 250 μg/ml, respectively. To investigate biofilm inhibition and degradation effect, crystal violet assay and stainless steel were used. Biofilm formation rates of four strains ( 7, 8, ATCC 25922, and O157:H4 FRIK 125) were 55.8%, 70.2%, 55.4%, and 20.6% at 1/2 × MIC of GSE, respectively. The degradation effect of GSE on biofilms attached to stainless steel coupons was observed (≥ 1 log CFU/coupon) after exposure to concentrations above the MIC for all strains and 1/2 × MIC for 7. In addition, the specific mechanisms of this anti-biofilm effect were investigated by evaluating hydrophobicity, auto-aggregation, exopolysaccharide (EPS) production rate, and motility. Significant changes in EPS production rate and motility were observed in both and in the presence of GSE, while changes in hydrophobicity were observed only in . No relationship was seen between auto-aggregation and biofilm formation. Therefore, our results suggest that GSE might be used as an anti-biofilm agent that is effective against and .
葡萄柚籽提取物（GSE）是一种安全有效的防腐剂，广泛应用于食品工业。然而，目前关于 GSE 抗生物膜作用的研究较少。本研究考察了 GSE 对 和 生物膜形成菌株的抗生物膜作用。GSE 对 和 的最低抑菌浓度（MIC）分别为 25μg/ml 和 250μg/ml。为了研究生物膜抑制和降解作用，采用结晶紫法和不锈钢片进行实验。4 株菌（ 7 、 8 、ATCC 25922 和 O157:H4 FRIK 125）在 GSE1/2MIC 时的生物膜形成率分别为 55.8%、70.2%、55.4%和 20.6%。所有菌株 MIC 以上浓度和 7 的 1/2MIC 以上浓度暴露后，观察到 GSE 对附着在不锈钢片上的生物膜有降解作用（≥1logCFU/片）。此外，通过评估疏水性、自动聚集、胞外多糖（EPS）产生率和运动性，研究了这种抗生物膜作用的具体机制。在 GSE 的存在下， 和 中 EPS 产生率和运动性均发生显著变化，而疏水性仅在 中发生变化。自动聚集与生物膜形成之间未见相关性。因此，我们的结果表明 GSE 可能作为一种有效的抗生物膜剂，用于抑制 和 。
