Characterization of nitrite degradation by polyphenols in sea buckthorn (Hippophae rhamnoides L.) by density function theory calculations

The objective of this study was to investigate the nitrite-degrading capacity of polyphenols in sea buckthorn and explore the relationship between structures and degradation capacity with quantum chemistry. The results showed that polyphenols in sea buckthorn had a higher nitrite degrading capacity than other compounds, with the nitrite-degrading rate of 75.9%, the chlorogenic acid, isorhamnetin, luteolin 3'-O-arabinoside, L-epicatechin, isosinensetin, rutin, luteolin 3'-O-beta D glucuronide, catechin, quercetin 3'-O-glucoside, epigallocatechin contents changed significantly in the presence of nitrite. The bonding dissociation energy indicated the Delta E of chlorogenic acid for the 7-OH site was 290.2853 kcal/mol, lower than other phenolic monomers, while Mulliken electron density difference of oxygen and hydrogen in corresponding hydroxyl group was larger than other polyphenols, which were in accordance with the higher nitrite degradation. These results indicated that the nitrite degradation rates were closely related to bonding dissociation energy and Mulliken electron density, and could be estimated by the two indicators.

Automated summary

This study investigated the nitrite-degrading capacity of polyphenols in sea buckthorn and explored the relationship between structures and degradation capacity using quantum chemistry. Results showed that polyphenols in sea buckthorn had higher nitrite degrading capacity and this was related to bonding dissociation energy and Mulliken electron density. These findings suggest that nitrite degradation rates can be estimated by these two indicators.