Dados do Trabalho

Título

JAMBU (Acmella oleracea (L.) R.K. Jansen): PHYSICOCHEMICAL AND MORPHOMETRIC CHARACTERISTICS OF LEAVES PRODUCED IN CONVENTIONAL AND HYDROPONIC SYSTEMS

Introdução

The leaves of Acmella oleracea (L.) R.K. Jansen (jambu) are considered the main commercial product of the plant, which has important cultural and culinary, values especially in the north of Brazil. In this study, morphometric and physicochemical characteristics of jambu leaves cultivated in conventional (CS) and hydroponic (HS) growth systems were investigated for the first time in the scientific literature.

Material e Métodos

The species studied in this work was identified by Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) and obtained a registration code: IAN 196473. The leaves were harvested and frozen at -20 °C ± 2 ºC for analysis of protein, fat, ash, titratable acidity, and pH. For theses analysis, the AOAC guideline was used. For the analysis of carotenoids, chlorophylls, and ascorbic acid, the leaves were frozen at -80 °C ± 2 ºC. The moisture and color analysis were performed immediately after harvest. For minerals analyses (Potassium, Calcium, Magnesium, Phosphorus, Sulfur, Iron, Manganese, zinc, and copper), the leaves were dried for 12 h in a circulating air oven.

Resultados e Discussão

Moisture and primary metabolites, such as protein, fat, and total chlorophyll, were found in higher content in jambu leaves cultured in HS compared to the CS. HS leaves also presented the highest amount of minerals, ash, pH, and titratable acidity (% oxalic acid). In contrast, secondary metabolites concentrations on the plant leaves, including ascorbic acid and total carotenoids, were greater in CS. The leaves cultivated in HS showed significantly (p < 0.05) greater values for all morphometric parameters. The cultivation systems showed a significant difference (p < 0.05) for all parameters analyzed (L*, a, and b) for both leaf surfaces (adaxial and abaxial).

Conclusão

The hydroponic and conventionally cultured leaves showed differences regarding their morphometrics and histochemical characteristics. Thus, it is possible to conclude that jambu growth in different cultivation systems (CS and HS) can influence its anatomical and physicochemical characteristics. These results demonstrated that the hydroponically cultivated leaves presented overall better morphometric characteristics and improved minerals and nutrients compositions