Phytopathology. 1997 Feb;87(2):161-3. doi: 10.1094/PHYTO.1997.87.2.161.
ABSTRACT An assay for determination of galacturonic acid with 3,5-dinitrosalicylic acid was developed that substantially extends the linear range of detection compared to a previously published method with this reagent. In the improved assay, galacturonic acid was detected with a reagent containing 44 mM 3,5-dinitrosalicylic acid, 4 mM sodium sulfite, and 375 mM sodium hydroxide. The absorbance of the solution after reaction with galacturonic acid was determined at 575 nm and was linear at concentrations of galacturonic acid up to 50 mumol, with a lower limit of detection at ~400 nmol. The assay with the improved reagent could be performed in wavelength ranges from 550 to 575 nm, with higher sensitivity at the shorter wavelengths. The new reagent was used in routine assays of polygalacturonase activity in culture filtrates of the important postharvest fungal pathogen Mucor piriformis.
摘要 开发了一种用 3,5-二硝基水杨酸测定半乳糖醛酸的测定法，与以前用该试剂发表的方法相比，该方法大大扩展了检测的线性范围。在改进的测定法中，半乳糖醛酸用含有 44mM 3,5-二硝基水杨酸、4mM 亚硫酸钠和 375mM 氢氧化钠的试剂检测。与半乳糖醛酸反应后的溶液在 575nm 处测定吸光度，在半乳糖醛酸浓度高达 50μmol 时呈线性，检测下限约为 400nmol。用改良试剂进行的测定可在 550nm 至 575nm 的波长范围内进行，较短波长的灵敏度更高。新试剂用于测定重要的采后真菌病原体梨形毛霉的培养滤液中聚半乳糖醛酸酶活性的常规测定。
