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Joan Solé Albert Sans Magí Riba Gloria Rosell Esmeralda Rosa Lourdes Muñoz Maria Pilar Bosch Angel Guerrero 《Chemoecology》2008,18(2):99-108
Summary. The differing antagonist activity of (Z)-13-hexadecen-2-one (Z11 – 14 :MK, 1) and its 1,1,1-trifluoro derivative (Z11 –14 :TFMK, 2), two closely related analogues of the European corn borer pheromone Ostrinia nubilalis (Z strain), and their rationale is reported. Both chemicals exhibited some electrophysiological activity, and topical application
of 10 pg of pheromone analogue on male antennae was sufficient to induce significantly lower depolarization responses to the
pheromone versus untreated insects. In a wind tunnel, the number of European corn borer males attracted to sources containing
mixtures of 1 + pheromone in ratios ≥ 1 :1 was significantly lower than the number attracted to a source containing pheromone alone. Source
contact behaviour was dramatically impaired when the 1 + pheromone blend reached a ratio of 10 :1, in which only 2% of males displayed source contact in the presence of antagonist.
When compound 1 was present at the source, males usually flew upwind with occasional downwind reversals; when compound 2 was present at the lure, males performed wider crosswind reversals, with little progress toward the source. In the field,
traps baited with mixtures of both compounds with the pheromone in ratios of 5 :1 and 10 :1 elicited a significantly decreased
number of male catches. In esterase inhibition assays, compound 2 was a potent inhibitor (IC50 = 70 nM), whereas the non-fluorinated compound 1 was not. The different activity of both compounds is presumed to be due to different mechanisms of action; considerations
for using methyl ketone analogues as new behavioural antagonists of the pheromone are outlined. 相似文献
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具脂肪酶和酯酶活性酵母菌的选育和酶学性质初步研究 总被引:7,自引:0,他引:7
从济南市区得到的含油土壤中筛选得到一株酵母S9 菌株,它可以同时产生较高酶活的脂肪酶和酯酶.对影响S9 产脂肪酶和酯酶的各种因素进行了研究,确定2 % 的黄豆粉为最佳氮源,1 % 的可溶性淀粉为最佳碳源,最适的初始培养pH和温度分别为pH6 .5 和28℃,另外不同的表面活性剂对产酶也有不同的影响.对S9脂肪酶和酯酶的各种酶学性质进行的研究表明,脂肪酶和酯酶的最适作用温度都为30℃,最适作用pH 分别为7 .0 和8.0,两者都属于常温酶,在30℃~40 ℃范围内比较稳定,前者在中性偏碱的pH 环境中比较稳定,后者属于碱性酶,在pH7 .5~10 .5 范围内相当稳定. 相似文献