龙须菜(Gracilaria lemaneiformis)高温逆境代谢产物的GC-MS分析

VOLATILE METABOLITES IN GRACILARIA LEMANEIFORMIS AT HIGH TEMPERATURE

利用固相微萃取(SPME)和气相色谱/质谱联用技术(GC-MS)分析龙须菜在高温逆境中可挥发性代谢产物的变化规律。最优分析条件为样品60℃平衡30min,用聚二甲基硅氧烷-二乙烯基苯纤维头(PDMS/DVB)顶空萃取吸附25min,在210℃下解吸附5min后对解吸物进行GC-MS检测。结果表明,从龙须菜中检测到56个挥发性代谢产物,在高温逆境条件下主要有烯烃(61.67%)、醛(22.47%)、酮(5.98%)、烷烃(1.92%)、卤代物(0.65%)、醇(0.41%)、酯(0.37%)、其它(1.34%)。比较了常温和高温逆境培养条件下龙须菜中代谢产物的相对含量变化规律:高温胁迫下E-2-戊烯醛等7种代谢产物含量显著减少,三氯甲烷等4种代谢产物含量显著增加。其中E-2-庚烯醛、E,E-2,4-庚二烯醛、2-正戊基呋喃和三氯甲烷可能与龙须菜高温逆境生理有关。本研究可为龙须菜抗逆生理和抗高温品系选育提供理论依据和指导。

The volatile metabolites in Gracilaria lemaneiformis cultured in high temperature stress is studied with headspace solid-phase microextraction （SPME） and gas chromatography-mass spectrometry （GC-MS） techniques. In opti- mized analytic conditions, the samples are brought into equilibrium at 60℃ for 30 rain and extracted for 25 min with PDMS/DVB fiber coating; after released for 5 min in 210℃, the volatile compounds are analyzed with GC-MS. A total of 56 types of volatile compounds, including alkenes （61.67%）, aldehydes （22.47%）, ketones （5.98%）, normal paraffin hy- drocarbons （1.92%）, halogenated compounds （0.65%）, alcohols （0.41%）, and esters （0.37%） have been identified from the Gracilaira cultured in 33℃. Variations in the culture between high and normal temperature are recorded. Seven metabolites, including E-2-pentenal, E-2-heptenal, E,E-2,4-heptadienal, 2-pentyl-furan, E,E-2,4-nonadiene, 3,5-dimethyl-cyclohexanol, and pentadecane decrease under high temperature stress, while chloroform, tridecane, heptadecane, and nonadecane increase. Among them, the content change of E-2-heptenal, E,E-2,4-heptadienal, 2-pentyl-furan, and chloroform may be related to the high temperature resistance of G. lemaneiformis.