Usefulness of rapid GC analysis of cellular fatty acids for distinguishing Weissella viridescens, Weissella paramesenteroides, Weissella hellenica and some non-identifiable, arginine-negative Weissella strains of meat origin

Abstract

In an attempt to differentiate between Weissella viridescens, W. paramesenteroides, W. hellenica and some atypical arginine-negative Weissella isolates from meats, their cellular fatty acid composition was determined by a rapid GC method. Results showed that W. viridescens synthesized eicosenoic (n-C20:1) acid, while the other two species did not. Meanwhile, unlike W. paramesenteroides, W. hellenica lacked cyclopropane fatty acids with 19 carbon atoms, i.e. dihydrosterculic or lactobacillic acid. Weissella viridescens contained zero to low amounts (< 1%) of C19 cycl. Original meat isolates identified as W. viridescens or W. hellenica shared similar fatty acid profiles with the respective type strains, whereas the "wild" atypical Weissella isolates resembled more with W. paramesenteroides, and all together with Leuconostoc mesenteroides subsp. mesenteroides. Interesting variations were noted in the total C19 cycl contents among unidentified Weissella, being generally consistent with their grouping based on the type of lactate they formed and the whole-cell protein profile similarity they shared.