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Fermentation technology was used to prepare the acaí (Euterpe oleracea) fermentation liquid. The optimal fermentation parameters included a strain ratio of Lactobacillus paracasei: Leuconostoc mesenteroides: Lactobacillus plantarum = 0.5:1:1.5, a fermentation time of 6 days, and a nitrogen source supplemental level of 2.5%. In optimal conditions, the ORAC value of the fermentation liquid reached the highest value of 273.28 ± 6.55 μmol/L Trolox, which was 55.85% higher than the raw liquid. In addition, the FRAP value of the acaí, as well as its scavenging ability of DPPH, hydroxyl, and ABTS free radicals, increased after fermentation. Furthermore, after fermentation treatment, the microstructure, basic physicochemical composition, amino acid composition, γ‐aminobutyric acid, a variety of volatile components, and so on have changed. Therefore, fermentation treatment can significantly improve the nutritional value and flavor of the acaí. This provides a theoretical basis for the comprehensive utilization of acaí. [ABSTRACT FROM AUTHOR]

Abstract: From an acid hydrolysate of the crude saponins of Gynostemma pentaphyllum, three triterpenes, including a new compound (23S)-3β-hydroxydammar-20,24-dien-21-oic acid 21,23-lactone (1) and two known aglycons (20S, 23R)-3β,20β-dihydroxydamma-24-dien-21-oic acid 21,23-lactone (2) and (20S, 24S)-20,24-epoxydammarane-3β,12β,25-triol (3), were isolated. Their structures were established on the basis of extensive spectral evidence (HR-ESI-MS, IR, 1D and 2D-NMR experiments). In bioactive assays in vitro, compound 1 was found to have potent cytotoxicity against the human breast cancer cells MDA-MB-435, whereas compounds 2 and 3 exhibited modest inhibitory activity toward porcine pancreatic lipase. The results indicated that acid treatment of G. pentaphyllum extract could produce diverse structures with interesting bioactivity. [Copyright &y& Elsevier]

Thirty-eight phenolic compounds (including 31 flavonoids) were examined for their DPPH radical-scavenging activities, and structure-activity relationships were evaluated. Specifically, the presence of an ortho-dihydroxyl structure in phenolics is largely responsible for their excellent anti-radical activity. 3-Hydroxyl was also essential to generate a high radical-scavenging activity. An increasing number of hydroxyls on flavones with a 3',4'-dihydroxyl basic structure, the presence of a third hydroxyl group at C-5', a phloroglucinol structure, glycosylation and methylation of the hydroxyls, and some other hydroxyls, for example 5-, and 7-hydroxyl in ring A, decreased the radical-scavenging activities of flavonoids and other phenolics.