Hexane

Methanol, hexane, chloroform, ethyl acetate and ethanol were purchased from Junsei Chemical Co., Ltd., Tokyo, Japan. Potassium phosphate monobasic and dibasic, xanthine, xanthine oxidase, allopurinol, and hydrochloric acid were obtained from Sigma-Aldrich Corp., St. Louis, MO, USA. Reagents including 1,1-diphenyl-2-picrylhydrazyl (DPPH), sodium acetate, acetic acid, 2,2′-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), potassium peroxodisulfate, and dibutyl hydroxytoluene (BHT) were supplied by Kanto Chemical Co. Inc., Tokyo, Japan. Four bacteria including Staphylococcus aureus, Escherichia coli, Bacillus subtilis, and Proteus mirabilis were provided by Sigma-Aldrich Corp., St. Louis, MO USA. All chemicals used were of analytical grade.

Acrylamide, acetonitrile, α-cyano-4-hydroxycinnamic acid, bis-Acrylamide, benzamidine, Bradford solution, p-coumaric acid, caffeic acid, 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate hydrate (CHAPS), 1,4-dithiothreitol (DTT), ferulic acid, fluorescein (FL), γ-aminobutyric acid (GABA), gallic acid, 4-hydroxybenzoic acid, iodoacetamide, phenylisothiocyanate, syringic acid, sodium dodecyl sulfate (SDS), Trolox, trifluoroAcetic acid, thiourea, urea, and vanillic acid were purchased from Sigma Aldrich (St. Louis, MO, USA). Acetic acid, dipotassium phosphate, ethanol, hydrochloric acid, hexane, sodium hydroxide, monopotassium phosphate, methanol, and water were obtained from Junsei Chemical (Tokyo, Japan), and 2,2′-azobis(2-amidinoprpane) dihydrochloride solution (ABAP) was purchased from Wako Chemicals (Richmond, VA, USA). Pharmalyte (pH 3.5–10) and IPG Dry Strips (pH4–10 NL, 24 cm) were purchased from Amersham Biosciences and from Genomine Inc. (Pohang-si, Korea), respectively. Porcine trypsin was obtained from Promega (Madison, WI, USA).

Acinetobacter oleivorans DR1, a diesel degrader, has been characterized in our previous studies (Kang and Park, 2010; Jung et al., 2011a; Kim and Park, 2013; Heo et al., 2014) and was used in this study. For the growth test of strain DR1, a seed culture was incubated in nutrient broth (Difco, Livonia, MI, USA) at 30°C and 220 r.p.m. overnight. Next, 1 ml of the seed culture was transferred to a 1.7‐ml microtube and washed twice with phosphate‐buffered saline (PBS, pH 7.4). Next, 1 × 10⁵ to 1 × 10⁶ CFU ml⁻¹ of strain DR1 was transferred into 20 ml of minimal salt basal (MSB) medium (Hong et al., 2014) in a 50‐ml flask to observe the growth on different alkanes [0.1% (v/v for liquid alkanes C₁₂–C₂₂, w/v for solid alkanes C₂₄–C₃₀) alkanes]. However, M9 minimal media (Kang et al., 2011) was used to conduct only CAS assay for measurement of siderophore production during hexadecane metabolism. Growth curves were generated based on the colony‐forming unit (CFU) owing to water insolubility. All hydrocarbons (n‐alkanes) were purchased from Sigma‐Aldrich (St Louis, MO, USA), except for hexane (Junsei, Tokyo, Japan), decane (Wako, Osaka, Japan), decanol (Alfa Aesar, Haverhill, MA, USA), hexadecanol (Daejung, Gyeonggi‐do, Korea) and hexadecanoic acid (Junsei).