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Background: The scientific literature has studies that assess the influence of erosive challenges with citric acidic drinks and substances on the adhesive bond strength to enamel and dentin, but does not contain information about the influence of regional components of an acidic diet on this process. Thus, this study evaluated the erosive influence of Amazonian tucupi on enamel and dentin microshear bond strength. Materials and Methods: One hundred and sixty-eight healthy bovine incisors teeth were used, divided into 12 groups (n = 14). For erosive cycling, distilled water (negative control), cola-based soft drink (positive control), or tucupi were used, followed by adhesive strategies of (1) etch-and-rinse (conventional) (Adper™ Single Bond 2) and (2) self-etching (Clearfil SE Bond). All specimens were subjected to erosive cycling for 5 days and, after 24 h, composite resin cylinders were built up for the microshear bond strength test. The data showed normal distribution and were analyzed by two-way ANOVA, followed by the Tukey post and test (P = 0.05). Results: There were no significant differences in enamel (P > 0.05). In dentin, only the groups exposed to cola-based soft drink showed significant differences (P < 0.01). The failure mode showed that Type II (mixed) was predominant (95%). Conclusion: The erosive challenge with tucupi did not influence the bond strength to enamel and dentin, regardless of the adhesive strategy used. [ABSTRACT FROM AUTHOR]

Phenolic compounds and carotenoids profile of Amazonian Eryngium foetidum leaves and the quenching ability of their hydrophilic extract against singlet oxygen (¹O2) were determined. Chlorogenic acid (4327 μg/g, dry basis, d.b.) was the major phenolic compound in the leaves at very high concentrations, while lutein (205 μg/g, d.b.) and β-carotene (161 μg/g, d.b.) were the major carotenoids. The extract of E. foetidum leaves was able to scavenge DPPH● (91.6% at 5 mg/mL), ABTS●+ (15.77 μM Trolox equivalent/g extract) and it exhibited high efficiency to protect tryptophan against ¹O2, with IC50 at 343 μg/mL and 78% of protection at the highest tested concentration (625 μg/mL). Therefore, E. foetidum leaves can be exploited as an accessible natural source of bioactive compounds with antioxidant properties to be used by the food or pharmaceutical industries. [ABSTRACT FROM AUTHOR]

Jambolão fruits are promising sources of anthocyanins, and in this study, the jambolão fruit from the Brazilian Amazonian region was characterized and the efficiency of six ethanol-based solutions to extract anthocyanins was determined. Moreover, the color changes of anthocyanin extracts, as influenced by different pH conditions (pH from 1.0 to 8.0), were evaluated. The fruits exhibited high contents of total anthocyanins (296 mg/100 g) and the CIELAB parameters characterized jambolão as a purple-red colored fruit ( a* = 20.30, b* = −4.17, and [ABSTRACT FROM AUTHOR]

Cassava flour from dry and water groups are important starch products widely consumed in the Amazonian region of Brazil. In this study, the moisture sorption isotherms of cassava flour from dry and water groups were obtained in the water activity (aw) range from 0.09 to 0.94 (dry group) and 0.07 to 0.93 (water group) at 25°C and the applicability of eight mathematical models in data prediction was evaluated. Both cassava flour from dry and water groups exhibited type II isotherms (sigmoid) and the hysteresis effect between adsorption and desorption isotherms was shown almost over the entire range of aw. The moisture of cassava flour from dry and water groups should not exceed 11.3g H2O 100g-1 (aw=0.6) to ensure the theoretical microbiological stability and the monolayer moisture value (9.0 and 7.9 g H2O 100g-1, respectively) indicated the level of moisture content to be reached during the drying process to avoid unnecessary power consumption. Finally, the data fit showed that the mathematical model of GAB were able to predict efficiently the sorption isotherms of both cassava flour from dry and water group at the entire aw range. [ABSTRACT FROM AUTHOR]