## 2 Materials and Methods  
### Sampling, Enrichments, and Growth  
The seawater sample was collected from the northern coastline of Johor Strait in Malaysia. The water sample (1 mL) was added into 250 mL flasks containing 100 mL of minimal medium and TCA as a carbon source. Minimal medium contained basal salts solution, trace metals solution; and distilled water. The composition and proportion of the constituent of the minimal medium are shown in Table 1. The medium was adjusted to pH 7 before autoclaving. Then, the bacterial culture was incubated aerobically at 30 \({}^{\circ}\)C conditions in an orbital shaker set at 200 rpm. In order to prepare a solidified medium, two flasks (labeled Flask 1 and Flask 2) were prepared. Flask 1 contained 1.6 g oxide agar added into 48 mL distilled water (DW). Flask 2 was filled with 10 mL of trace metal salts and 10 mL of basal salts added into 30 mL DW. Flask 1 and flask 2 were autoclaved separately at 121 \({}^{\circ}\)C, for 15 min at 101.3 kPa. After autoclaving, solution in both flasks 1 and 2 were mixed and 1 mL of 1 M concentration TCA was added to the mixture, and the obtained medium was poured on agar plates. After the solidification of the agar, bacterial dilution was streaked onto the plates. Among the isolated strains, three different bacterial colonies were detected that the colony with the highest growth rate was retained for further purification. No further study was carried out for the identification of the two other isolated bacteria strains. The selected colony was picked and sub-cultured by repeated streaking on a fresh agar plate to purify for further analysis. The selected colony was diluted in a drop of distilled water and transferred into minimal medium containing the ingredients shown in Table 1.  
The bacteria were grown in minimal medium containing TCA as the sole carbon source. Chlorine atoms are eliminated by hydrolytic dehalogenation from the compound [48]. Chloride ion liberation had been monitored by the halide ion assay to prove the degradation of TCA [49]. The concentration of chloride ions was determined by converting absorbance value to concentration in mmol-L\({}^{-1}\) based on the standard curve constructed using sodium chloride as the standard measurement of soluble chloride [50; 51]. The suspension of the selected colony was used to evaluate the growth profile and TCA degradation. Several direct and indirect methods can be used for the evaluation of the bacterial growth profile. A colony-forming unit (CFU) is a direct method to evaluate the actual colony forming units per volume of culture in given bacterial incubation. The enumeration of CFU is one of the most accurate methods to find out the number of viable bacteria strains growing in the presence of harsh chemicals [52]. On the other hand, the spectrophotometric method is a widely used laboratory technique to indirectly estimate the bacterial concentration and quantitative analysis of the released chloride ions [44; 53]. Spectrophotometry methods are based on the absorption and scattering of light beams passing through the culture medium. These methods are sensitive and selective; however, enumeration of CFU by plate count might be a disadvantage due to the fact that cells grown in clusters into a single colony and assumption that each colony arises from one cell is not accurate. In addition, commercial TCA may contain impurities and colony count may due to the growth of impurities rather than on TCA. In this study, absorbance A\({}_{680\mathrm{nm}}\) and A\({}_{460\mathrm{nm}}\) are used for analysis of the bacterial growth and released chloride ions, respectively. Chloride was liberated during the growth of TCA. The absorbance of the released chloride ions was recorded every 6 h using Jenaway spectrophotometer at A\({}_{460\mathrm{nm}}\). Growth experiment and chloride ion released analysis were carried out in triplicate.