N decanoyl dl homoserine lactone

Live turbot were collected from a local aquatic products market (Jinzhou, China) and transferred to the laboratory with oxygenated water. The fish were killed and rinsed with sterile water. Then, the sample was vacuum-packed and refrigerated at −2 °C for 28 days. N-butanoyl-dl-homoserine lactone (C₄–HSL), N-hexanoyl-dl-homoserine lactone (C₆–HSL), N-octanoyl-dl-homoserine lactone (C₈–HSL), N-decanoyl-dl-homoserine lactone (C₁₀–HSL), N-dodecanoyl-dl-homoserine lactone (C₁₂–HSL), N-tetradecanoyl-dl-homoserine lactone (C₁₄–HSL) were purchased from Sigma-Aldrich (Poole, UK). Other reagents used in this study were commercially available and of analytical grade. Chromobacterium violaceum CV026 and Agrobacterium tumefaciens A136 were stored at our laboratory.

The following AHL standards, purchased from University of Nottingham, UK were: N-3-oxo-butyryl-L-homoserine lactone (3OC4-HSL), N-3-hydroxy-butyryl-L-homoserine lactone (3OHC4-HSL), N-3-hydroxy-hexanoyl-L-homoserine lactone (3OHC6-HSL), N-3-hydroxy-octanoyl-L-homoserine lactone (3OHC8-HSL), N-3-hydroxy-decanoyl-L-homoserine lactone (3OHC10-HSL). In addition, N-butyryl-DL-homoserine lactone (C4-HSL), N-hexanoyl-L-homoserine lactone (C6-HSL), N-3-oxo-hexanoyl-L-homoserine lactone (3OC6-HSL), N-octanoyl-L-homoserine lactone (C8-HSL), N-3-oxo-octanoyl-L-homoserine lactone (3OC8-HSL), N-decanoyl-DL-homoserine lactone (C10-HSL), N-3-oxo-decanoyl-L-homoserine lactone (3OC10-HSL), N-dodecanoyl-DL-homoserine lactone (C12-HSL), N-3-oxo-dodecanoyl-L-homoserine lactone (3OC12-HSL), N-3-hydroxy-dodecanoyl-DL-homoserine lactone (3OHC12-HSL), acetonitrile, and formic acid for HPLC were obtained from Sigma-Aldrich (St. Louis, MO, USA).

The following AHL standards were purchased from University of Nottingham, UK: N-3-oxo-butyryl-L-homoserine lactone (3-oxo-C4-HSL), N-3-hydroxy-butyryl-L-homoserine lactone (3-OH-C4-HSL), N-3-hydroxy-hexanoyl-L-homoserine lactone (3-OH-C6-HSL), N-3-hydroxy-octanoyl-L-homoserine lactone (3-OH-C8-HSL), N-3-hydroxy-decanoyl-L-homoserine lactone (3-OH-C10-HSL). Standards purchased from Sigma-Aldrich were: N-butyryl-DL-homoserine lactone (C4-HSL), N-hexanoyl-L-homoserine lactone (C6-HSL), N-3-oxo-hexanoyl-L- homoserine lactone (3-oxo-C6-HSL), N-octanoyl-L-homoserine lactone (C8-HSL), N-3-oxo-octanoyl-L-homoserine lactone (3-oxo-C8-HSL), N-decanoyl-DL-homoserine lactone (C10-HSL), N-3-oxo-decanoyl-L-homoserine lactone (3-oxo-C10-HSL), N-dodecanoyl-DL-homoserine lactone (C12-HSL), N-3-oxo-dodecanoyl-L-homoserine lactone (3-oxo-C12-HSL), and N-3-hydroxy-dodecanoyl-DL-homoserine lactone (3-OH-C12-HSL). HPLC grade acetonitrile and formic acid were purchased from Merck.