AUTHOR=Li Yingchao , Jia Ru , Al-Mahamedh Hussain H. , Xu Dake , Gu Tingyue 

TITLE=Enhanced Biocide Mitigation of Field Biofilm Consortia by a Mixture of D-Amino Acids

JOURNAL=Frontiers in Microbiology

VOLUME=7

YEAR=2016

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2016.00896

DOI=10.3389/fmicb.2016.00896

ISSN=1664-302X

ABSTRACT=<p>Microbiologically influenced corrosion (MIC) is a major problem in the oil and gas industry as well as in many other industries. Current treatment methods rely mostly on pigging and biocide dosing. Biocide resistance is a growing concern. Thus, it is desirable to use biocide enhancers to improve the efficacy of existing biocides. <sc>D</sc>-Amino acids are naturally occurring. Our previous work demonstrated that some <sc>D</sc>-amino acids are biocide enhancers. Under a biocide stress of 50 ppm (w/w) hydroxymethyl phosphonium sulfate (THPS) biocide, 1 ppm <sc>D</sc>-tyrosine and 100 ppm <sc>D</sc>-methionine used separately successfully mitigated the <italic>Desulfovibrio vulgaris</italic> biofilm on carbon steel coupons. The data reported in this work revealed that 50 ppm of an equimolar mixture of <sc>D</sc>-methionine, <sc>D</sc>-tyrosine, <sc>D</sc>-leucine, and <sc>D</sc>-tryptophan greatly enhanced 50 ppm THPS biocide treatment of two recalcitrant biofilm consortia containing sulfate reducing bacteria (SRB), nitrate reducing bacteria (NRB), and fermentative bacteria, etc., from oil-field operations. The data also indicated that individual <sc>D</sc>-amino acids were inadequate for the biofilm consortia.</p>