Altering the thermal resistance of foodborne bacterial pathogens with an eggshell membrane waste by-product.
Altering the thermal resistance of foodborne bacterial pathogens with an eggshell membrane waste by-product.
复制标题
用蛋壳膜废物副产品改变食源性细菌病原体的耐热性。
DOI：
10.4315/0362-028x-64.4.486
复制
发表时间：
2001
影响因子：
2
通讯作者：
B. Sheldon
中科院分区：
文献类型：
--
作者：
A. Poland;B. Sheldon
破蛋作业产生的蛋壳是一个重大的废物处理问题。因此，从这种废物中开发增值副产品将受到工业界的欢迎。研究了含有溶菌酶和β -n -乙酰氨基葡萄糖苷酶或其他膜组分的蛋壳膜对革兰氏阳性和革兰氏阴性细菌病原菌耐热性的影响。将肠炎沙门氏菌（SE）、鼠伤寒沙门氏菌（ST）、大肠杆菌O157:H7 （EC）、单核增生李斯特菌Scott A （LM）和金黄色葡萄球菌（SA）的中期细胞悬浮在含有0（对照）或10 g蛋壳膜提取物的100 ml 0.1%蛋白胨水（pH 6.9, 10(7-8) CFU/ml）中，在37℃下孵育45分钟。暴露后，在密封的玻璃反应瓶（12 × 32 mm）中，将无膜样品（1.5 ml）在56℃（LM， SA）， 54℃（SE， ST）或52℃（EC）水浴中加热0至14分钟，幸存者在脑心脏灌注琼脂上回收。与对照组相比，用提取膜处理45分钟的细胞数量减少了27.6% （SA）至99.8% (LM) （ST, 43.8%； SE, 47.5%； EC, 71.8%）。当膜处理的细胞随后被热灭活时，d值降低范围从0 （LM）到87.2% (SE) （SA, 36.7%； EC, 83.3%； ST, 86.3%）。用鼠伤寒沙门菌评价了暴露pH、时间、温度和有机负荷对膜活性的影响。暴露于pH （5.0 vs 6.9）、时间（15 vs 45 min）和温度（4℃vs 37℃）并没有显著降低蛋壳膜对d值的影响。然而，有机物质（0.1%蛋白胨水和脱脂牛奶）的存在显著降低了膜的热阻还原能力。这些初步发现为提取蛋壳膜改变细菌耐热性的潜在用途提供了信息。
Eggshells from egg-breaking operations are a significant waste disposal problem. Thus, the development of value-added by-products from this waste would be welcomed by the industry. The ability of extracted eggshell membranes containing, several bacteriolytic enzymes (i.e., lysozyme and beta-N-acetylglucosaminidase) or other membrane components to alter the thermal resistance of gram-positive and gram-negative bacterial pathogens was evaluated. Mid-log phase cells of Salmonella Enteritidis (SE), Salmonella Typhimurium (ST), Escherichia coli O157:H7 (EC), Listeria monocytogenes Scott A (LM), and Staphylococcus aureus (SA) were suspended in 100 ml of 0.1% peptone water (pH 6.9, 10(7-8) CFU/ml) containing either 0 (control) or 10 g of an eggshell membrane extract and incubated at 37 degrees C for 45 min. Following exposure, membrane-free samples (1.5 ml) were heated in a 56 degrees C (LM, SA), 54 degrees C (SE, ST), or 52 degrees C (EC) water bath from 0 to 14 min in sealed glass reaction vials (12 by 32 mm), and the survivors were recovered on brain heart infusion agar. Population reductions ranging from 27.6% (SA) to 99.8% (LM) (ST, 43.8%; SE, 47.5%; EC, 71.8%) were observed for cells treated for 45 min with extracted membrane, as compared to controls. D-value reductions ranging from 0 (LM) to 87.2% (SE) (SA, 36.7%; EC, 83.3%; ST, 86.3%) were observed when membrane-treated cells were subsequently heat inactivated. The effects of exposure pH, time, temperature, and organic load on membrane activity were also evaluated with Salmonella Typhimurium. Exposure pH (5.0 versus 6.9), time (15 versus 45 min), and temperature (4 degrees C versus 37 degrees C) did not significantly reduce the impact of eggshell membranes on D-values. However, the presence of organic matter (0.1% peptone water versus skim milk) significantly reduced the thermal resistance-reducing capacity of the membranes. These preliminary findings provide information on the potential use of extracted eggshell membranes to alter bacterial heat resistance.