不同平均聚合度低聚壳聚糖对毛白杨相关酶活性的影响

Effects of different average polymerization degree chitosan-oligosaccharides on related enzyme activities in Populus tomentosa

【目的】研究不同聚合度低聚壳聚糖对毛白杨愈伤组织苯丙氨酸解氨酶(PAL)和几丁质酶活性的影响。【方法】采用H2O2氧化法分别降解壳聚糖2,4,5,6h,用乙酰丙酮法测定这几种产物的平均聚合度,通过检测不同质量浓度各种低聚糖处理后毛白杨愈伤组织PAL及几丁质酶活性的变化,确定各低聚壳聚糖处理的最佳质量浓度,比较最佳质量浓度下4种低聚壳聚糖处理对毛白杨愈伤组织PAL及几丁质酶活性的诱导效果。【结果】低聚糖的平均聚合度随降解时间的延长而不断减小,降解2,4,5,6h时平均聚合度分别为24.94,17.68,14.66和10.02,这4种低聚壳聚糖均能使毛白杨愈伤组织中的PAL及几丁质酶活性显著升高,且以质量浓度为75mg/L、平均聚合度为10.02的低聚壳聚糖的诱导效果最佳,由其诱导的毛白杨愈伤组织中的PAL活性及几丁质酶活性分别是对照的4.31和3.11倍。【结论】在设定的平均聚合度和质量浓度范围内,平均聚合度越低的低聚壳聚糖对毛白杨愈伤组织PAL和几丁质酶活性的诱导效果越好。

【Objective】 The experiment was done to study the effect induced by four chitosan-oligosaccharides of phenylalanine ammonia lyase（PAL） and chitinase activity on Populus tomentosa callus.【Method】 The chitosan-oligosaccharides were made with H2O2 to decompose chitosan for 2,4,5 and 6 hours,and the average polymerization degree of these chitosan-oligosaccharides elicitors was determined by using the acetylacetone＇s method.The study determined the best inducing concentration of every elicitor by measuring the effect of PAL and chitinase activity on Populus tomentosa callus which was induced by four chitosan-oligosaccharides with different concentrations,and compared the effect of PAL and chitinase activity on Populus tomentosa callus induced by every elicitor with the best concentration.【Result】 The average polymerization degree of chitosan-oligosaccharides decreased as degradation reaction continued,the average polymerization degree of the products was 24.94,17.68,14.66 and 10.02 when the decomposed time achieved 2,4,5 and 6 hours,these four chitosan-oligosaccharides elicitors could induce the increase of PAL and chitinase activity notablely,and the elictor whose average degree of polymerization was 10.02 showed the best inductive effect when its concentration was 75 mg/L,PAL and chitosan achieved the highest activity which was 4.31 and 3.11 times as high as the each control enzyme activity.【Conclusion】 Lower polymerization degree of chitosan-oligosaccharides had a better inductive effect when the concentration and polymerization degree were in the range of our research.