Table 2 LC–ESI–MS identification of surfactin and iturin type of homologues produced by B. velezensis SK, and comparison of their Molecular weight and peptide sequence reported in literature (Dhanarajan et al. 2016; Goswami and Deka 2019; Souza et al. 2018; De Faria et al. 2011; Dang et al. 2019; Liu et al. 2020; Chen et al. 2020)
RT (min) | Observed MW [M + H]+ (m/z) | Average MW reported | Identified lipopeptide | Relative % of lipopeptide family | Amino acid sequence (Obtained from literature) |
|---|---|---|---|---|---|
HP-20 Extract | |||||
Peak first | |||||
45.89 | 1043.58 | 1042.7 | C14-Iturin | 11.37 | Cyclic (FA-N-Y-N-Q-P-N-S) |
49.97 | 1057.59 | 1057.6 | C15-Iturin | 5.00 | Cyclic (FA-N-Y-N-Q-P-N-S) |
55.33 | 1071.61 | 1071.7 | C16-Iturin | 6.86 | Cyclic (FA-N-Y-N-Q-P-N-S) |
Peak second | |||||
63.52 | 994.67 | 994.21 | C12-Surfactin | 17.49 | Cyclic (FA-E-L/I-L/I-V- L/I- D-L) |
1008.69 | 1008.87 | C13-Surfactin | 27.73 | Cyclic (FA-E-L/I-L/I-V- L/I -D-L) | |
1022.70 | 1023.18 | C14-Surfactin | 19.11 | Cyclic (FA-E-L/I-L/I-V-V-D-L) | |
1036.72 | 1036.78 | C15 Surfactin | 12.40 | Cyclic (FA-E-L/I-L/I-V- L/I -D-L) | |
Fraction 2 (40% Acetone pH 4) | |||||
Peak first | |||||
45.88 | 1043.58 | 1042.7 | C14-Iturin | 0.71 | Cyclic (FA-N-Y-N-Q-P-N-S) |
50.48 | 1057.59 | 1057.6 | C15-Iturin | 0.20 | Cyclic (FA-N-Y-N-Q-P-N-S) |
Peak second | |||||
62.42 | 1036.72 | C15-Surfactin | 44.34 | Cyclic (FA-E-L/I-L/I-V-D -L/I-L) | |
63.54 | 994.67 | 994.21 | C12-Surfactin | 54.74 | Cyclic (FA-E-L/I-L/I-V-D-L/I-L) |
1008.69 | 1008.87 | C13-Surfactin | Cyclic (FA-E-L/I-L/I-V-D-L/I-L) | ||
1022.70 | 1023.18 | C14-Surfactin | Cyclic (FA-E-L/I-L/I-V-D-L/I-L) | ||
1036.72 | 1036.78 | C15-Surfactin | Cyclic (FA-E-L/I-L/I-V-D-L/I-L) | ||
1050.73 | 1050.92 | C16-Surfactin | Cyclic (FA-E-L/I-L/I-V-D-L/I-L) | ||
Fraction 5 (80% Acetone pH 8) | |||||
62.20 | 994.67 | 994.21 | C12-Surfactin | 24.17 | Cyclic (FA-E-L/I-L/I-V-D-L/I-L) |
63.38 | 1022.70 | 1023.18 | C14-Surfactin | 32.18 | Cyclic (FA-E-L/I-L/I-V-D-L/I-L) |
1036.72 | 1036.78 | C15-Surfactin | 43.64 | Cyclic (FA-E-L/I-L/I-V-D-L/I-L) | |