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Abstract The available drugs for treating Leishmaniasis and American trypanosomiasis have high toxicity and multiple side effects, among other problems. More effective and less toxic treatments are urgently needed. A series of chalcones that contained a prenyloxy or geranyloxy substituent was synthesized and characterized. Each substituent was attached to the A ring in some compounds and to the B ring in others, with additional substituents placed on the chalcone moiety. The present aim was to evaluate the effect of the substitution pattern on leishmanicidal and trypanocidal activity. When tested at a single concentration, the compounds exerting a metabolic inhibition close to or exceeding 50% for Leishmania mexicana were 11 , 17 and 12 , and for Trypanosoma cruzi were 11 , 17 , 15 and 26. Upon determining the selectivity index (SI =IC 50 /CC 50), the values were 80.9, 1.24 and 55.12 for 11 , 17 and 12 (respectively) versus L. mexicana , and 75.1, 1.43, 27.36 and 33.52 for 11 , 17 , 15 and 26 (respectively) versus T. cruzi. Structural isomers 11 and 17 showed activity for both the L. mexicana and T. cruzi strains, though the greater cytotoxic activity of 17 led to a lower SI. Compounds 12 , 15 and 26 were species specific. For T. cruzi , the SI was higher for 11 , 15 and 26 than for the reference drugs nifurtimox and benznidazole. The examination of promastigote morphology after exposing L. mexicana and T. cruzi to 11 revealed a decrease in cell density. The current findings suggest that 11 could be a useful lead compound for further SAR studies. Graphical abstract Image 1 Highlights • Prenyloxylated chalcones display metabolic inhibition against Leishmania mexicana and Trypanosoma cruzi. • Prenyloxy groups attached to A-ring display less cytotoxicity against macrophages. • Structural isomers of chalcones display different selectivity indexes. • Three of the synthesized chalcones shown better selectivity index than reference drugs for Trypanosoma cruzi. [ABSTRACT FROM AUTHOR]

The effectiveness of maltodextrin (10%) and cactus mucilage (CM) (0%, 0.25%, 0.50%, 0.75%, and 1%) as carrier agents was evaluated in the encapsulation of bioactive amaranth compounds. Spray drying, an efficient encapsulation method, achieved high yields (62.9%–68%). The increase in CM concentration significantly augmented the water absorption index (WAI), bulk density, and hygroscopicity of the encapsulated amaranth powders. Conversely, it significantly decreased the moisture content, water activity, and water solubility index (WSI). The glass transition temperatures (>40 °C), Hausner ratio (HR), and Carr's index (CI) values indicated the suitability of powders for handling and processing. Moreover, no cracks were observed in the microcapsules surface, which favoured the bioactive amaranth compounds retention and stability. Thus, low degradation rate constants and long half-life time values were determined for the encapsulated amaranth powders, indicative of its storage appropriateness. Incorporation of 0.75% CM was an efficient concentration to achieve high percentage retention of betacyanins (55.5%), betaxanthins (58%), total polyphenols (73.3%), amaranthine (56.8%), isoamaranthine (62.7%), individual polyphenols (44.6%–81%), and antioxidant activity (79.6%). These results demonstrated the efficiency of CM as an encapsulating agent in the food industry. [ABSTRACT FROM AUTHOR]

• UV-C irradiation was identified as an alternative way of Aloe vera gel processing. • Thermal treatment (TT) affected simple sugar content more than UV-C irradiation. • In contrast to TT, UV-C irradiation did not strongly affect molecular weight. • TT resulted in more pronounced deacetylation of acemannan than UV-C irradiation. • Acemannan quantification was performed by 1H NMR. The effects of pH (3.5, 4.5, and 5.5) and UV-C irradiation dose (12.8, 24.2, 35.8, and 54.6 mJ/cm2) on the physicochemical properties changes in 10% Aloe vera gel blends; in addition, the acemannan concentration and structural changes in the precipitated polysaccharides were evaluated. A thermal treatment (TT; 45 s at 90 °C) was used for comparison. In contrast to TT, a dose of 24.2 mJ/cm2 did not induce significant changes of free sugar content. Moreover, TT and UV-C irradiation did not significantly affect the content of mannose but increased those of galactose, fructose, and glucose. 1H NMR analysis revealed minimal changes in the isolated fractions of acemannan, indicating that compared to the unprocessed control sample, the acemannan deacetylation was more pronounced by TT (27%) than by UV-C irradiation (11% at 54.6 mJ/cm2), without any significant difference between the two. UV-C irradiation of Aloe vera gel blends at pH 3.5 and 24.2 mJ/cm2 was an alternative to TT and efficiently preserve the characteristics of acemannan. [ABSTRACT FROM AUTHOR]