超氧化物歧化酶、丙二醛、脯氨酸作为裂殖壶菌菌种性能评价的新指标

Superoxide dismutase，malondialdehyde and proline as new quality criteria for Schizochytrium sp．Fermentation

摘要:

摘要:【目的】对不同Schizochytrium sp.HX-308种子期超氧化物歧化酶(SOD)、丙二醛(MDA)和脯氨酸(Pro)进行测定，旨在寻找出一种评价菌种质量优劣的新方法。【方法】选用Schizochytrium sp．HX-308中的1株驯化高产菌株和1 株原始菌株在正常条件下活化，以及同一原始菌株分别在正常条件和恶劣条件下活化的2组实验，分别通过WST-1法、巴比妥酸比色法和比色法测定SOD、MDA和Pro含量，探讨不同菌株中这3个指标与裂殖壶菌Schizochytrium sp．HX-308最终发酵性能之间的关系。【结果】发酵性能最佳的驯化菌株整个种子期的SOD、MDA和Pro含量都最低，平均仅为0.025U/g、26.20mmol/g·Fw和0.098mg/g·Fw，而发酵性能最差的恶劣条件下菌株的SOD已达到了它的6 倍以上，MDA和Pro也达到了2倍以上。【结论】本研究最终证实，这3个指标与菌株的发酵性能呈负相关关系，可以作为评价裂殖壶菌菌株发酵性能优劣的新指标，为菌株选育的优化提供了指导。

Abstract:

Abstract:［Objective］The aim of our study was to find a novel method to evaluate the strain quality of Schizochytrium sp.HX-308．［Methods］An acclimatized strain and an original strain were cultivated under normal condition．Meanwhile，the same acclimatized strain was cultured under two different conditions，the optimum condition and the harsh condition．We detected the activity of superoxide dismutase and the contents of malondialdehyde and proline by WST-1 method，thiobarbituric acid test and colorimetry，respectively． The relationship between the three criteria and the fermentation performance of Schizochytrium sp．HX-308 was studied．［Results］ The acclimatized strain cultured under the optimal fermentation condition had the lowest superoxide dismutase activity (0.025U/g protein)，malondialdehyde (26.20 mmol/g·Fw) and proline contents(0.098 mg/g·Fw)．In contrast，the superoxide dismutase activity of the original strain cultured in the harsh conditions was 5 times higher than that of the acclimatized strain，the malondialdehyde and proline contents were both 2 times as high as the acclimatized strain． ［Conclusion］The three criteria were correlated negatively with the fermentation performance．Thus，they could be used to evaluate quality and fermentation performance of Schizochytrium sp．