原果胶在稀酸溶液中水解为可溶性果胶，与原有的可溶性果胶进一步转化为半乳糖醛酸，半乳糖醛酸在强酸环境中与咔唑缩合生成紫红色化合物，产物在530 nm处具有特征吸收峰，通过吸光值变化即可定量检测总果胶的含量。
标准物质： Galacturonic Acid①若样品质地坚硬，可先研碎后再进行匀浆，或使用匀浆器匀浆；
②浓硫酸质量对显色体系具有一定的影响，建议使用优级纯或分析纯浓硫酸，标准品显色完成后应为红色，若出现明显绿色则应该更换浓硫酸后再进行试验；
③浓硫酸具有强腐蚀性，操作时需特别注意：应缓慢加入以防止液面沸腾烫伤及样本碳化，90℃处理结束后需冷却至室温再进行后续操作，以防液体飞溅烧伤；
④若测定吸光值超出标准曲线线性吸光值范围：高于最高值建议将待测样本使用提取液B适当稀释后再进行测定，低于最低值建议适当增加样本量后再进行测定，计算时相应修改；
[1] Bi W, Yin Y, Ding C, et al. Insights into the antagonistic effects of calcium on cadmium accumulation in peanuts (Arachis hypogaea L.)[J]. Journal of Environmental Management, 2024, 367: 122003. (IF 8.0)
[2] Chen B, Zhang Y, Sun Z, et al. Tissue‐specific expression of GhnsLTPs identified via GWAS sophisticatedly coordinates disease and insect resistance by regulating metabolic flux redirection in cotton[J]. The Plant Journal, 2021, 107(3): 831-846.(IF 6.486)
[3] Du Y, Gao F, Yuan S, et al. Metabolomic, transcriptomic and physiological analysis reveal the effects and potential mechanisms of cold plasma treatment on resistance of wolfberry during storage[J]. Postharvest Biology and Technology, 2024, 218: 113128. (IF 6.4)
[4] Tang J, Li Y, Gong S, et al. AaAO, AaPDE, and AaABC proteins promote Alternaria alternate f. sp. mali ALT7 invasion in apple leaves[J]. Horticultural Plant Journal, 2025. (IF 5.7)
[5] Mao J, Gao Z, Lin M, et al. Targeted multi-platform metabolome analysis and enzyme activity analysis of kiwifruit during postharvest ripening[J]. Frontiers in Plant Science, 2023, 14: 1120166.(IF 5.6)
[6] Sun W, Chen Y, Zeng J, et al. The Tartary buckwheat bHLH gene ALCATRAZ contributes to silique dehiscence in Arabidopsis thaliana[J]. Plant Science, 2023, 333: 111733.(IF 5.2)
[7] Yu H, Yuan Y, Wang S, et al. Interspecies evolution and networks investigation of the auxin response protein (AUX/IAA) family reveals the adaptation mechanisms of halophytes crops in nitrogen starvation agroecological environments[J]. Agriculture, 2021, 11(8): 780.(IF 2.925)