Seasonal and pluviometric effects on the phenolic compound composition and antioxidant potential of Licania macrophylla Benth (Chrysobalanaceae), a medicinal plant from the Amazon rainforest

Abstract Licania macrophylla is a medicinal plant from the Amazon. It is mainly used in the form of a decoction and has been reported to contain several phenolic compounds. However, the effect of seasonality on the phenolic composition and antioxidant potential of this plant has not been well studied, especially in the Amazon region, an area affected by the rainy and less-rainy seasons. Therefore, we evaluated the seasonality of these aromatic compounds and the antioxidant potential of the extracts from L. macrophylla stem bark. We also determined the correlation between the extraction methods used and precipitation levels during each period for 1 year. The total flavonoid and phenolic content, DPPH-scavenging potential, percentage of phosphomolybdenum complex reduction, and iron-reducing power were quantified. The levels of phenolic compounds were the highest in June, whereas those of flavonoids were the highest in September and October; however, these differences were not significant. The extracts from April, November, and June showed the best results for DPPH scavenging, phosphomolybdenum reduction, and iron reduction power, respectively. Significant differences in the phenolic content and DPPH-scavenging activity were observed between the more- and less-rainy seasons. The total phenolic content was positively correlated with FRAP and DPPH, whereas flavonoid levels were negatively correlated.

Laboratory-Scale Preparation and Characterization of Dried Extract of Muirapuama (Ptychopetalumolacoides Benth) by Green Analytical Techniques.

This work reports on the preparation of a drying process from the ethanolic extract of Muirapuama and its characterization through green analytical techniques. The spray-drying processes were performed by using ethanolic extract in a ratio of 1:1 extract/excipient and 32 factorial design. The properties of dried powder were investigated in terms of total flavonoid content, moisture content, powder yield, and particle size distribution. An analytical eco-scale was applied to assess the greenness of the developed protocol. Ultra-high performance liquid chromatography (UHPLC)with reduced solvent consumption in the analysis was compared to the conventional HPLC method. A Fourier transform near-infrared (FT-NIR) spectroscopic method was applied based on the principal component scores for the prediction of extract/excipient mixtures and partial least squares regression model for quantitative analysis. NIR spectroscopy is an economic, powerful, and fast methodology for the detection of excipient in muirapuama dried extracts, generating no residue in the analysis. Scanning electron microscopy (SEM) images showed samples with a higher concentration of excipient, presenting better morphological characteristics and a lower moisture absorption rate. An eco-scale score value of 85 was achieved for UHPLC and 100 was achieved for NIR (excellent green analysis). Above all, these methods are rapid and green for the routine analysis of herbal medicines based on dried extracts.