Department of Food Science, Faculty of Food Engineering, University of Campinas (UNICAMP), Campinas, SP, 13083-862, Brazil.
World J Microbiol Biotechnol. 2012 Apr;28(4):1781-90. doi: 10.1007/s11274-011-0993-y. Epub 2011 Dec 31.
In this study, the carotenoids produced by the extremophile microorganisms Halococcus morrhuae, Halobacterium salinarium and Thermus filiformis were separated and identified by high-performance liquid chromatography connected to a diode array detector and a tandem mass spectrometer. The in vitro scavenging capacity of the carotenoid extracts against radical and non-radical species was evaluated. In halophilic microorganisms, the following carotenoids were identified: bacterioruberin, bisanhydrobacterioruberin, trisanhydrobacterioruberin and their derivatives. In the thermophilic bacterium, the carotenoids all-trans-zeaxanthin, zeaxanthin monoglucoside, thermozeaxanthins and thermobiszeaxanthins were identified. The antioxidant capacities of the carotenoid extracts of H. morrhuae (trolox equivalent antioxidant capacity = 5.07 and IC(50) = 0.85 μg mL(-1)) and H. salinarium (trolox equivalent antioxidant capacity = 5.28 and IC(50) = 0.84 μg mL(-1)) were similar and higher than those of the bacterium T. filiformis (trolox equivalent antioxidant capacity = 2.87 and IC(50) = 2.41 μg mL(-1)). This difference is related to the presence of acyclic carotenoids with both large numbers of conjugated double bounds and of hydroxyl groups in the major carotenoid of the halophilic microorganisms.
在这项研究中，通过高效液相色谱法与二极管阵列检测器和串联质谱仪相连，分离并鉴定了嗜盐微生物盐沼盐杆菌、盐生盐杆菌和嗜热丝状菌产生的类胡萝卜素。评估了类胡萝卜素提取物对自由基和非自由基物质的体外清除能力。在嗜盐微生物中，鉴定出了菌红素、双脱水菌红素、三脱水菌红素及其衍生物。在嗜热菌中，鉴定出了类胡萝卜素全反式玉米黄质、玉米黄质单葡糖苷、热玉米黄质和热双玉米黄质。H. morrhuae（trolox 当量抗氧化能力=5.07，IC50=0.85 μg mL-1）和 H. salinarium（trolox 当量抗氧化能力=5.28，IC50=0.84 μg mL-1）类胡萝卜素提取物的抗氧化能力与 T. filiformis（trolox 当量抗氧化能力=2.87，IC50=2.41 μg mL-1）相似且更高。这种差异与嗜盐微生物主要类胡萝卜素中含有大量共轭双键和羟基的无环类胡萝卜素有关。
