Changes of Polyphenols, Pigments and Related Enzyme Activities in Cigars Leaves of Different Positions During Air-curing

In order to clarify the degradation of polyphenols and plastid pigments and the changes of related enzyme activities in cigar leaves during air-curing, taking Dexue No.1 as the test material, the changes of polyphenols, plastid pigments and related enzyme activities in leaves at different positions of cigar tobacco were studied, and the correlation analyses were carried out. The results showed that the polyphenol contents showed cutters > lower leaf > upper leaf at different positions of cigar plants. The chlorogenic acid content showed a downward trend at all positions, but rutin and scopoletin showed a single peak curve. The plastid pigment gradually decreased with the air-curing process, and it showed upper leaf > cutters > lower leaf. The activities of lipoxygenase, phenylalanine ammonia lyase, polyphenol oxidase and peroxidase at different positions of cigar first increased and then decreased. Correlation analysis showed that polyphenol oxidase activity was positively correlated with polyphenols and pigment content at different positions during air-curing, and significant correlations with chlorogenic acid and β-carotene were also observed. The negative correlations were observed between phenylalanine ammonia lyase activity and polyphenols and pigments, and the significant correlations with chlorogenic acid. Significant positive correlations were observed between peroxidase and lipoxygenase, phenylalanine ammonia lyase and polyphenol oxidase. Therefore, reasonable regulation of enzyme activities during air-curing can control the content of polyphenols and plastid pigments, which is beneficial to improvement of the curing characteristics of cigar.