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Abstract: BACKGROUND: Guayusa (Ilex guayusa Loes.) leaves, native of the Ecuadorian Amazon, are popularly used for preparing teas. This study aimed to assess the influence of leaf age on the phenolic compounds and carotenoids and the bioactivity and digestibility (in vitro) of aqueous and hydroalcoholic leaf extracts. RESULTS: In total, 14 phenolic compounds were identified and quantified. Chlorogenic acid and quercetin‐3‐O‐hexose were the main representatives of the hydroxycinnamic acids and flavonols respectively. Seven carotenoids were quantified, lutein being the main compound. Ripening affected phenolic content significantly, but there was no significant difference in carotenoid content. Antioxidant capacity, measured by the DPPH• method, was also significantly affected by leaf age. The measurement of in vitro digestibility showed a decrease in phenolic content (59%) as well as antioxidant capacity, measured by the ABTS•+ method, in comparison with initial conditions of the guayusa infusion. Antibacterial and anti‐inflammatory activities were assayed with young leaves owing to their higher phenolic contents. Guayusa did not show any antibacterial activity against Escherichia coli ATCC 25922 or Staphylococcus aureus ATCC 25923. Finally, the hydroalcoholic and aqueous extracts exhibited high in vitro anti‐inflammatory activity (>65%). CONCLUSION: Young guayusa leaves have potential applications as a functional ingredient in food and pharmaceutical industries. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Guayusa ( Ilex guayusa Loes) is an evergreen tree native of South America that grows particularly in the upper Amazon region of Ecuador. For its health benefits, it has been cultivated and consumed since ancient times by Amazon indigenous tribes. RESULTS A total of 14 phenolic compounds were identified and quantified. Chlorogenic acid and quercetin-3- O-hexose were the main representatives of the hydroxycinnamic acids and flavonols, respectively. Five carotenoids were identified, showing lutein the highest concentration. Guayusa leaves revealed high antioxidant capacity determined by two analytical methods, DPPH and ORAC. The industrial processing applied to the leaves modified the composition of bioactive compounds and antioxidant capacity of guayusa. In general, blanched guayusa retained the concentration of phenolic compounds and some carotenoids and similar antioxidant capacity as untreated green leaves. In contrast, fermentation reduced the content of bioactive compounds and showed the lowest antioxidant capacity. CONCLUSION Therefore, blanched guayusa has potential for product development as a functional ingredient in the food industry. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Brassica spp. sprouts are rich in nutrients and bioactive compounds, especially glucosinolates and phenolic acid derivatives, and the composition of these young germinating seeds can be altered by several external factors. In this study two cabbage varieties ( Brassica oleracea var. capitata, red and white) were studied using seed priming ( KCl 50 mmol L−1; NaCl 150 mmol L−1) and MeJA spraying (25 µmol L−1) to elicit the phytochemical content of edible sprouts. RESULTS The red variety was richer in glucosinolates and phenolic compounds than the white one but not in mineral nutrients. Seed priming enhanced the potassium (K) content and flavonols in both varieties, while the total content of glucosinolates was reduced after seed priming only in the red variety. The white variety responded better than the red one to KCl seed priming, increasing the flavonols (89%). Salinity did not induce any change in the phytochemical content of these two varieties. Elicitation with sprayed MeJA was effective in significantly increasing the content of indolic glucosinolates glucobrassicin (5.7-fold) and neoglucobrassicin (9.7-fold) in the red cultivar. In the white variety, in addition to glucobrassicin (19.4-fold) and neoglucobrassicin (9.4-fold), 4-hydroxyglucobrassicin (2.3-fold) was also enhanced. MeJA also elicited significant amounts of anthocyanins (41%) and chlorogenic acid derivatives (329%) in the white variety. CONCLUSION KCl seed priming and MeJA elicitation promoted the phytochemical composition of the cabbage varieties, especially in the white variety. The application of NaCl resulted in less efficient elicitation. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]