Amazon Assai (Euterpe precatoria): The search for biorefinery process at the byproducts from pulp industry

Euterpe precatoria Mart. is one of the Euterpe species known as Assai, with several medicinal and supplementary properties that have being explored to the production of energetic drinks obtained from the pulp of the fruit. Chemically, the pulp of the fruit, as its juice, is characterized by the presence of polyphenolic compounds with antioxidant properties. There are no studies in the literature on the huge amount of waste material generated in the processing of Assai pulps. The aim of this study was to develop extraction processes in order to obtain extracts with antioxidant activity. The fruits were collected in Coari, AM (Brazil), pulp and seeds were separated, dried and crushed. The seed extractions were performed by techniques of maceration and sonication and the solvents were ethanol and water (ratios of 100, 80, 50 and 20%). Folin Ciocalteu [1] and aluminum chloride [2] methods were applied to evaluate total flavonols and phenolic amount at the different extracts. The effects from solvent composition and extraction methodology on phenolic content and DPPH scavenging activities were evaluated by Multivariate Analysis of Variance (MANOVA) based on a factorial experiment with multivariate response. The best result for antioxidant activity, amount of total flavonoids and phenols was obtained at ethanol extract with DPPH inhibition of 72.81 ± 1.33%, with 1.65 ± 0.10% of total flavonoids and 12.23 ± 0.58% of total phenols. The percentage of inhibition was close to the value found in the standard (quercetin). ISE-MS analysis allowed the detection of peaks corresponding to the phenolic compounds resveratrol, coumaric, piscidic and caftaric acids. The study allow the optimization of the phenol and flavonoid content and also an increase at antioxidant activity, higher than reported in the literature for pulp values, demonstrated that seed extracts are promising byproducts from Assai Amazonian industry.

References:

[1] Singleton, V. L., Rossi, J. A. Colorimetry of total phenolics with phosphomolybdic-phosphotungstic acid reagents. American Journal of Enology and Viticulture, 1965; 16, 144 – 158.

[2] Zhishen, J., Mengcheng, T., Jianming, W. The determination of flavonoid contents in mulberry and their scavenging effects on superoxide radicals. Food Chemistry, 1999; 64, 555 – 559.