THE PROFILE OF CAPSAICINOIDS AND PIGMENTS BIOSYNTHESIS AS A SIGNAL FOR THE RIPENING AND SENESCENCE PROCESSES OF CAPSICUM FRUITS

Abstract

The relationship between the accumulation of pigments regarding with the capsaicinoids contents and the maturation state of fruits from several Capsicum species was investigated. The capsaicinoids profile showed a stationary phase of accumulation during the transition from the green to red, yellow or orange final color, characteristic of each species. After the color transition phase, when maturation was reached, the stationary phase for capsaicinoids accumulation was stable for 10-15 days, until the fruits come into senescence, state that can be appreciated by the changes in morphology, mainly loss of turgor and wilting. This final stage of maturation starts with the lowering in the amount of capsaicinoids and the start of the transition phase from the green to the final color of the fruits. When the accumulation of pigments reaches its maximum the fruit shriveling, enters senescence, and the capsaicinoids content decreases to a minimum in all species studied. These observations indicate that the profile of capsaicinoids content have a direct metabolic correlation with the elongation of the fruits and inverse to the biosynthesis of pigments, acting as a chemical signal to stop the fruit elongation and for the start of pigments biosynthesis. The study on the profile for accumulation of both capsaicinoids and pigments showed that the end of the accumulation of capsaicinoids was gradually accompanied by the start of pigment biosynthesis, which supports the hypothesis that this metabolic change is the biochemical signal for the ripening and senescence processes of Capsicum fruits, assumption that is supported by the fact