Metabolic and antioxidant profiles of herbal infusions and decoctions.

This study implements NMR metabolomics and spectrophotometric studies (Folin-Ciocalteu, FRAP, ABTS) to infusions and decoctions of ten plant species in order to assess and compare the metabolic and antioxidant profiles for each botanical family. Multivariate and univariate data analyses highlighted the differences among the samples and pinpointed specific classes of compounds for each plant species as well as infusions and decoctions. The identified phenolic compounds by NMR, as well as the antioxidant profile, framed a trend of increased values in infusions compared to the decoctions. Moreover, the infusion procedure positively affected the extractability of the phenolic compounds compared to decoctions. The highest total phenolic content was found in Mentha spicata, while the lowest in Matricaria chamomilla preparations, irrespective of the preparation method. The preparation time for the decoctions was examined showing that the 15min preparations were generally found richer in phenolics and of higher antioxidant capacity.

Response surface methodology toward the optimization of high-energy carotenoid extraction from Aristeus antennatus shrimp.

High-energy assisted extraction techniques, like ultrasound assisted extraction (UAE) and microwave assisted extraction (MAE), are widely applied over the last years for the recovery of bioactive compounds such as carotenoids, antioxidants and phenols from foods, animals and herbal natural sources. Especially for the case of xanthophylls, the main carotenoid group of crustaceans, they can be extracted in a rapid and quantitative way with the use of UAE and MAE. Response surface methodology (RSM) is used for the optimization of extraction methodologies, also being applied to optimize high energy techniques. Three independent variables, namely extraction time, ultrasound or microwave power and solvent/material ratio, were investigated for both methods by employing a 16-run three-level Box-Behnken design (BBD). Considering the extraction efficiency for carotenoids from Aristeus antennatus shrimp, the selected conditions for UAE were 5 min, 600 W and 10:1 mL g(-1). Acetone was the solvent of choice for the extraction procedure. For MAE, the best experimental values were 7 min, 30 W and 20:1 mL g(-1) using n-hexane:acetone:ethanol 2:1:1 (v/v/v) as extraction solvent. The determination of total carotenoid yield was carried out using the spectophotometric calibration curve (A=0.1646(±0.0061)C-0.005(±0.022), R(2)=0.996, n=3) of a standard mix solution of canthaxanthin, zeaxanthin and lutein at 452.1 nm. Under the selected conditions, the yield of total carotenoids for UAE was 23.4(±2.3) and 6.73(±0.56) mg of carotenoids per 100 g dry sample for the head and the body of shrimp, while for MAE was 23.92(±0.63) and 13.3(±1.1) mg of carotenoids per 100g dry sample, respectively. The recovery of both methods was calculated between 60 and 105%. The results indicate that high-energy extraction techniques are faster, less laborious, more repeatable and reproducible methods than the conventional approaches for the quantitative recovery of sensitive bioactive compounds. Moreover, the recovery of a high-added value group of bioactive molecules from natural sources, such as carotenoids, can constitute a profitable and valuable commercial alternative, as these compounds can be used as dietary supplements, food color enhancers and additives in animal feeds, functional foods, preservatives, pharmaceuticals and cosmetics.