Microbiologically influenced corrosion (MIC) is a complicated process that happens ubiquitously and quietly in many fields. As a useful nutritional ingredient in microbial culture media, yeast extract (YE) is a routinely added in the MIC field. However, how the YE participated in MIC is not fully clarified. In the present work, the effect of YE on the growth of sulfate reducing prokaryotes (SRP) SY-1 and corrosion behavior of X70 pipeline steel were studied. It was found that the weight loss of steel coupons in sterile media was doubled when YE was removed from culture media. However, in the SRP assays without YE the number of planktonic cells decreased, but the attachment of bacteria on steel surfaces was enhanced significantly. Besides, the corrosion rate of steel in SRP assays increased fourfold after removing YE from culture media. MIC was not determined for assays with planktonic SRP but only for biofilm assays. The results confirm the effect of YE on SY-1 growth and also the inhibitory role of YE on MIC.

中文翻译：

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酵母提取物对 X70 管线钢脱硫弧菌 SY-1 微生物腐蚀的影响

微生物影响腐蚀（MIC）是一个复杂的过程，在许多领域中无处不在且悄然发生。作为微生物培养基中有用的营养成分，酵母提取物（YE）是 MIC 领域的常规添加物。然而，YE如何参与MIC尚不完全清楚。本工作研究了YE对硫酸盐还原原核生物（SRP）SY-1生长的影响以及X70管线钢的腐蚀行为。结果发现，当从培养基中除去 YE 时，无菌培养基中钢片的重量损失加倍。然而，在不含 YE 的 SRP 测定中，浮游细胞的数量减少，但细菌在钢表面的附着显着增强。此外，从培养基中去除 YE 后，SRP 测定中钢的腐蚀速率增加了四倍。未测定浮游 SRP 测定的 MIC，仅测定生物膜测定的 MIC。结果证实了YE对SY-1生长的作用以及YE对MIC的抑制作用。