X. hominickii was cultured in 1 L of TSB at 28°C for 48 h. After centrifuging cultured broth at 10,000 × g for 20 min at 4°C, the resulting supernatant was used for organic extraction as described by Mollah et al. [48 (link)]. Briefly, the supernatant was mixed with the same volume of hexane. After 30 min of incubation 4°C, the hexane extract (HEX) was separated from the aqueous fraction. The same procedure was sequentially used to obtain chloroform (CX), ethylacetate (EAX), and butanol (BX) extracts. Resulting organic extracts containing bacterial metabolites were dried with a rotary evaporator (Eyela N-1110, Rikakikai, Tokyo, Japan). After weighing, extracts were resuspended in methanol. TLC was performed for resulting extracts to obtain metabolites on a silica gel plate (20×20 cm; Merck, Darmstadt, Germany). Different compositions of chloroform and methanol (v/v) were used as eluents. The developed silica gel plate was incubated with a mixture (19:1, g/g) of sea sand (Merck) and iodine (Duksan, Ansan, Korea). Spots were visualized and marked in a fluorescence analysis cabinet (Spectroline, CM-10, Westbury, NY, USA).
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