甜橙果实膳食纤维与PG、Cx活性的研究

以红肉脐橙、纽荷尔脐橙和塔罗科血橙果实为试材，测定了果实发育过程中总膳食纤维（TDF）、可溶性膳食纤维（SDF）、不溶性膳食纤维（IDF）、总果胶（TP）、原果胶（protopectin）、水溶性果胶（WSP)、纤维素（CEL）、半纤维素（HC）和木质素（lignin）等的含量以及多聚半乳糖醛酸酶（PG）和纤维素酶（Cx）活性。结果表明：3个品种果实发育过程中总膳食纤维含量变化趋势基本一致，随着果实的成熟含量逐渐减少；果肉中，塔罗科血橙TDF含量最少，纽荷尔次之，红肉脐橙最多；IDF含量变化趋势与TDF基本一致，而SDF与TDF相反。果实发育过程中果胶含量呈下降趋势，果肉中表现较果皮明显；WSP含量随着果实成熟不断增加。随着果实的发育，木质素和HC含量急剧下降，且果肉中木质素和HC含量与Cx活性呈显著负相关；PG活性在果实发育前期较低，随着果实的成熟迅速增加，在11月初达到最大值后急剧下降。

The Relationship Between the Activity of PG and Cx with Dietary Fibre in Sweet Orange Fruit

TDF(total dietary fiber),IDF(insoluble dietary fiber),SDF(soluble dietary fiber),CEL (cellulose), HC(hemicellulose),TP(total pectin),Protopectin, WSP(water soluble pectin)and PG, Cx enzymes activities were determined in the peel and pulp of Cara Cara, Newhall navel orange and Tarocco San- guine at different development stages. The results showed that TDF contents in the peel and pulp of three sweet oranges decreased gradually during the whole developmental period and the change tendency were identical in three varieties. Tarocco Sanguine orange TDF contents were least, Newhall were next, Cara cara most. The change tendency of TDF contents was accord with IDF, but against With SDF. Pectin contents decreased in fruit especially in pulp. WSP contents increased slighty during the later stage. Following the growth of the fruit, the lignin and HC in fruit decreased rapidly. Lignin and HC contents were opposite correlated with Cx activity markedly. PG activity was lower in the early growth period, along with the fruit mature increased quickly, and decreased rapidly after the maximization at the beginning of November.