Departamento de Ciência de Alimentos, Faculdade de Engenharia de Alimentos, Universidade de Campinas , Campinas, SP , Brasil.
Braz J Microbiol. 2012 Jan;43(1):126-34. doi: 10.1590/S1517-838220120001000014. Epub 2012 Jun 1.
A fractional factorial design 2(5-1) was used to evaluate the effect of temperature, pH, and concentrations of yeast extract, tryptone and Nitsch's trace elements on the biomass, total carotenoids and protection against singlet oxygen by carotenoid extracts of the bacterium Thermus filiformis. In addition, the carotenoid composition was determined by high-performance liquid chromatography connected to a diode array and mass spectrometer detectors (HPLC-DAD-MS/MS). The production of biomass ranged from 0.113 to 0.658 g/L, the total carotenoid from 137.6 to 1,517.4 µg/g and the protection against singlet oxygen from 4.3 to 85.1 %. Results of the fractional factorial design showed that temperature had a negative effect on biomass production and a positive effect on carotenoid content and protection against singlet oxygen, besides, high levels of pH value, concentrations of yeast extract and tryptone had a positive effect on biomass production only at lower temperatures. The main carotenoids of T. filiformis were thermozeaxanthins. In the tested conditions, changes in the levels of the variables influenced the biomass, carotenoid production, and protection against singlet oxygen, although they did not influence the carotenoid profile. The results of this study provide a better understanding on the interactions among certain nutritional and cultivation conditions of a thermophile bacterium, Thermus filiformis, on biomass and carotenoid amounts, as well as on the antioxidant capacity.
采用 2(5-1)部分析因设计来评估温度、pH 值、酵母提取物、胰蛋白胨和 Nitsch 微量元素浓度对嗜热菌 Thermus filiformis 生物量、总类胡萝卜素和类胡萝卜素提取物对单线态氧的保护作用的影响。此外，通过高效液相色谱连接二极管阵列和质谱检测器（HPLC-DAD-MS/MS）来确定类胡萝卜素的组成。生物量的产量范围为 0.113 至 0.658 g/L，总类胡萝卜素的产量范围为 137.6 至 1517.4 µg/g，对单线态氧的保护作用范围为 4.3 至 85.1%。部分析因设计的结果表明，温度对生物量的产生有负面影响，对类胡萝卜素的含量和对单线态氧的保护作用有积极影响，此外，较高的 pH 值、酵母提取物和胰蛋白胨的浓度仅在较低的温度下对生物量的产生有积极影响。Thermus filiformis 的主要类胡萝卜素为热叶黄素。在测试的条件下，变量水平的变化影响了生物量、类胡萝卜素的产生和对单线态氧的保护作用，尽管它们没有影响类胡萝卜素的分布。这项研究的结果提供了对嗜热菌 Thermus filiformis 的某些营养和培养条件之间相互作用的更好理解，这些相互作用影响生物量和类胡萝卜素的产生，以及抗氧化能力。
