Elgaali Hesham, Hamilton-Kemp T R, Newman M C, Collins R W, Yu Keshun, Archbold D D
Department of Animal Sciences, University of Kentucky, Lexington, Kentucky 40546-0091, USA.
J Basic Microbiol. 2002;42(6):373-80. doi: 10.1002/1521-4028(200212)42:6<373::AID-JOBM373>3.0.CO;2-4.
Numerous reports have been published on the antimicrobial activity of synthetic volatile long chain alcohols, such as 1-decanol and 1-dodecanol, against bacteria and fungi. The objective of the present study was to survey microorganisms for emission patterns of naturally occurring long chain alcohols and other volatile components to determine if these compounds are associated with certain groups of bacteria. Cultures were grown in trypticase soy broth overnight and volatile compounds were trapped on a porous polymer and identified by mass spectrometry. Subsequently, volatile compounds were collected from 26 strains of food associated bacteria using solid-phase microextraction and analyzed by gas chromatography. Alcohols comprising 1-octanol, 1-decanol, and 1-dodecanol occurred as products from enteric Gram negative bacteria, which included Citrobacter, Enterobacter, Klebsiella, Salmonella, and Shigella. However, the long chain alcohols were not detected as products from the nonenteric Gram negative species studied which included Acinetobacter, Pseudomonas, and Shewanella. Among Gram positive bacteria, including Bacillus, Enterococcus, Lactococcus, Leuconostoc, Listeria, Staphylococcus, and Streptococcus, the only long chain alcohol detected was 1-decanol and, if present, it occurred in relatively small amounts. Other classes of compounds emitted by bacteria included methylketones and sulfides. The methylketones were found as products from Gram positive and Gram negative bacteria, whereas the sulfides were closely associated with Gram positive bacteria. In summary, the emission patterns of volatile compounds from bacteria showed many trends including the association of long chain alcohols with enteric Gram negative bacteria. The results provide a basis for future in vivo studies to determine if volatile compounds such as natural long chain alcohols function in the ecology of food-borne Gram negative bacterial pathogens.
关于合成挥发性长链醇（如1-癸醇和1-十二醇）对细菌和真菌的抗菌活性，已有大量报道。本研究的目的是调查微生物天然存在的长链醇和其他挥发性成分的排放模式，以确定这些化合物是否与某些细菌群体有关。将培养物在胰蛋白酶大豆肉汤中培养过夜，挥发性化合物被捕集在多孔聚合物上，并用质谱法进行鉴定。随后，使用固相微萃取从26株与食品相关的细菌中收集挥发性化合物，并通过气相色谱法进行分析。包含1-辛醇、1-癸醇和1-十二醇的醇类是肠道革兰氏阴性菌产生的产物，这些细菌包括柠檬酸杆菌属、肠杆菌属、克雷伯菌属、沙门氏菌属和志贺氏菌属。然而，在所研究的非肠道革兰氏阴性菌（包括不动杆菌属、假单胞菌属和希瓦氏菌属）中未检测到长链醇作为产物。在革兰氏阳性菌中，包括芽孢杆菌属、肠球菌属、乳球菌属、明串珠菌属、李斯特菌属、葡萄球菌属和链球菌属，唯一检测到的长链醇是1-癸醇，并且如果存在，其含量相对较少。细菌释放的其他化合物类别包括甲基酮和硫化物。甲基酮是革兰氏阳性菌和革兰氏阴性菌产生的产物，而硫化物与革兰氏阳性菌密切相关。总之，细菌挥发性化合物的排放模式显示出许多趋势，包括长链醇与肠道革兰氏阴性菌的关联。这些结果为未来的体内研究提供了基础，以确定天然长链醇等挥发性化合物在食源革兰氏阴性细菌病原体生态学中是否发挥作用。
