Halmi M I E, Jirangon Hussain, Johari W L W, Rachman A R Abdul, Shukor M Y, Syed M A
Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, UPM Serdang, 43400 Selangor, Malaysia.
Department of Environmental Science, Faculty of Environmental Studies, Universiti Putra Malaysia, UPM Serdang, 43400 Selangor, Malaysia ; Centre of Excellence for Environmental Forensics, Universiti Putra Malaysia, UPM Serdang, 43400 Selangor, Malaysia.
ScientificWorldJournal. 2014;2014:834202. doi: 10.1155/2014/834202. Epub 2014 Apr 1.
Luminescence-based assays for toxicants such as Microtox, ToxAlert, and Biotox have been used extensively worldwide. However, the use of these assays in near real time conditions is limited due to nonoptimal assay temperature for the tropical climate. An isolate that exhibits a high luminescence activity in a broad range of temperatures was successfully isolated from the mackerel, Rastrelliger kanagurta. This isolate was tentatively identified as Photobacterium sp. strain MIE, based on partial 16S rDNA molecular phylogeny. Optimum conditions that support high bioluminescence activity occurred between 24 and 30°C, with pH 5.5 to 7.5, 10 to 20 g/L of sodium chloride, 30 to 50 g/L of tryptone, and 4 g/L of glycerol as the carbon source. Assessment of near real time capability of this bacterial system, Xenoassay light to monitor heavy metals from a contaminated river running through the Juru River Basin shows near real time capability with assaying time of less than 30 minutes per samples. Samples returned to the lab were tested with a standard Microtox assay using Vibrio fishceri. Similar results were obtained to Xenoassay light that show temporal variation of copper concentration. Thus, this strain is suitable for near real time river monitoring of toxicants especially in the tropics.
基于发光的毒物检测方法，如Microtox、ToxAlert和Biotox，已在全球广泛使用。然而，由于热带气候下检测温度不理想，这些检测方法在近实时条件下的应用受到限制。从康氏马鲛（Rastrelliger kanagurta）中成功分离出一种在广泛温度范围内表现出高发光活性的菌株。基于部分16S rDNA分子系统发育分析，该菌株初步鉴定为发光杆菌属（Photobacterium）的MIE菌株。支持高生物发光活性的最佳条件为温度24至30°C、pH值5.5至7.5、氯化钠10至20 g/L、胰蛋白胨30至50 g/L以及作为碳源的甘油4 g/L。对该细菌系统Xenoassay light监测流经朱鲁河流域的受污染河流中重金属的近实时能力进行评估，结果表明其具有近实时能力，每个样品的检测时间不到30分钟。带回实验室的样品使用费氏弧菌（Vibrio fishceri）通过标准Microtox检测进行测试。获得了与Xenoassay light相似的结果，显示了铜浓度的时间变化。因此，该菌株适用于近实时监测河流中的毒物，尤其是在热带地区。
