Lu Yuyun, Nawrath Margarete, Sun Jingcan, Liu Shao-Quan
Food Science and Technology Program, Department of Chemistry, National University of Singapore, Science Drive 3, Singapore, 117543, Singapore.
National University of Singapore (Suzhou) Research Institute, 377 Lin Quan Street, Suzhou Industrial Park, Suzhou, Jiangsu, 215123, China.
AMB Express. 2018 Jul 3;8(1):109. doi: 10.1186/s13568-018-0639-7.
The present study investigated for the first time the effects of various physicochemical parameters on the production of volatile sulphur compounds (VSCs) by non-growing cells of Kluyveromyces lactis supplemented with L-methionine. The results showed that the production of VSCs positively correlated with the cell biomass, but it seemed that no clear relationship with L-methionine concentration existed. Temperature and pH significantly affected the formation of VSCs with more production at 30 °C and pH 5, respectively. Nitrogen supplementation (in the form of diammonium phosphate, DAP) repressed the production of VSCs. It is interesting to note that DAP and yeast extract supplementation induced the production of methional, but not Mn supplementation. The presence of Mn improved the production of methionol and dimethyl disulphide, but inhibited the formation of S-methyl thioacetate. The study indicated that optimization of physicochemical conditions and media composition would be crucial for producing L-methionine-derived VSC bioflavor.
本研究首次考察了各种理化参数对添加L-蛋氨酸的乳酸克鲁维酵母非生长细胞产生挥发性硫化物（VSCs）的影响。结果表明，VSCs的产生与细胞生物量呈正相关，但似乎与L-蛋氨酸浓度没有明显关系。温度和pH值分别显著影响VSCs的形成，在30℃和pH 5时产量更高。添加氮源（以磷酸二铵，DAP形式）会抑制VSCs的产生。值得注意的是，添加DAP和酵母提取物会诱导甲硫醛的产生，但添加锰则不会。锰的存在提高了甲硫醇和二甲基二硫的产量，但抑制了硫代乙酸甲酯的形成。该研究表明，优化理化条件和培养基组成对于生产L-蛋氨酸衍生的VSC生物风味物质至关重要。
