Abstract: Based on the topological theory and self-MATLAB program, Kier’s molecular connectivity indices (mXtv) and electro-negativity distance vector (Mt) were calculated for 41 volatile compounds in Chuliang Longan as identified by GC-MS. A five-element regression model of quantitative structure-retention relationship (QSRR) for retention index (RI) as a function of  mXtv and Mt was constructed using leaps-and-bounds regression (LBR). The traditional correlation coefficient (R2) and the cross-validation correlation coefficient (Q2) of leave-one-out (LOO) were 0.981 and 0.976, respectively. The robustness of the regression model was validated by Jackknife method, and the results showed that the R2 was between 0.975 and 0.986. The present study demonstrates that the model is highly reliable and has favorable predictive ability, and can better elucidate the change rule of GC-MS retention indices for organic components.

Key words: Chuliang longan, volatile composition, retention index, molecular connectivity indices, electro-negativity distance vector, quantitative structure-retention relationship (QSRR)