Betalains in Edible Fruits of Three Cactaceae Taxa-Epiphyllum, Hylocereus, and Opuntia-Their LC-MS/MS and FTIR Identification and Biological Activities Evaluation

Fruit Juices of Etcho (Pachycereus pecten-aboriginum) and Giant Cardon (Pachycereus pringlei) are Sources of Health-Promoting Ingredients with Potential Anticancer Properties

Mexico is one of the main diversification centers of cacti in the world, with more than 500 endemic species, most of which remain nutritionally and functionally uncharacterized. The columnar cacti of the genus Pachycereus comprise five underutilized endemic Mexican species, whose nutraceutical properties have only been studied in the P. weberi species. Therefore, this study aimed to evaluate the nutritional quality and bioactive properties of etcho (P. pecten-aboriginum) and giant cardon (P. pringlei) fruit. The physical, chemical, and nutritional composition of etcho and giant cardon fruits were characterized, as well as the profile and content of bioactive compounds, antioxidant activity (ABTS•+ and DPPH•), and antiproliferative capacity in cervical (HeLa) and breast cancer (MDA-MB-231, MCF-7, and T-47D) cell lines. Our results suggest that etcho and giant cardon fruits are rich sources of essential nutrients and bioactive phytochemicals (including K, Mg, P, dietary fiber, polyphenolic compounds, vitamin C, betalains, and myo-inositol) with antioxidant and anticancer potential by inhibiting the proliferation of all evaluated cell lines with IC50 values in the range of 198 to 287 µg of gallic acid equivalents/mL. Therefore, etcho and giant cardon fruits could be used for nutraceutical purposes, and their consumption could promote health benefits.

Antioxidant and Antimicrobial Effects of Baby Leaves of Amaranthus tricolor L. Harvested as Vegetable in Correlation with Their Phytochemical Composition

Amaranth is used as a spinach replacement; therefore, it is sometimes called Chinese Spinach. So far, the activity of the plant has not been associated with the presence of specific compounds. Three cultivars of Amaranthus tricolor L. were investigated for their antioxidant and antimicrobial activities. The correlation between the bioactivity and metabolite profiles was investigated in order to indicate active compounds in A. tricolor. The phytochemical profile of a total of nine extracts was studied by HPLC-DAD-ESI/HRMS, revealing the presence of 52 compounds. The highest antioxidant activity was noticed in the Red cultivar (0.06 mmol TE/g DE (Trolox Equivalent/Dry Extract Weight) and was related to the presence of amino acids, flavonoids and phenolic acids, as well as individual compounds such as tuberonic acid hexoside. All studied extracts revealed antimicrobial activity. Gram-positive bacteria were more susceptible to N-(carboxyacetyl) phenylalanine, phenylalanine, tuberonic acid and succinic acid and Gram-negative bacteria to dopa, tryptophan, norleucine, tuberonic acid hexoside, quercetin-O-hexoside, luteolin-O-rhamnosylhexoside, luteolin-6-C-hexoside succinic acid, gallic acid-O-hexoside, dihydroxybenzoic acid and hydroxybenzoic acid. Maleic acid showed promising antifungal activity. In summary, A. tricolor is a good source of antioxidant and antimicrobial compounds.

Comparison of the Chemical Properties of Pineapple Vinegar and Mixed Pineapple and Dragon Fruit Vinegar

Pineapples are a tropical fruit with high nutritional value and high vitamin and sugar contents. In this study, low-grade pineapples were fermented to produce vinegar using surface culture fermentation (SCF), which involved the addition of dragon fruit juice, to compare the quality and antioxidant activity of different preparations of vinegar. The highest acetic acid concentration (7.35%) was obtained from pineapple vinegar after 20 days of incubation. Vinegar made from mixed pineapple and dragon fruit juice without peel and vinegar with pineapple and dragon fruit juice with peel had acetic acid concentrations of up to 6.20% and 4.50%, respectively. The mixed-fruit vinegar of pineapple and dragon fruit juice with peel displayed the highest antioxidant activity at 210.74 µg/g TE, while no significant difference was found between the other two vinegars (189.52 vs. 187.91 µg/L TE). Notably, the volatile compounds detected in the vinegars were alcohols and esters, which may contribute to the distinct aroma. Overall, the addition of dragon fruit juice with peel to pineapple vinegar increased the phenolic content and antioxidant activity; however, fermentation was slightly slower than that of the other two test materials.

Metabolite Profiling Analysis and the Correlation with Biological Activity of Betalain-Rich Portulaca grandiflora Hook. Extracts

The aim of the study was to evaluate the possible correlation between the bioactivity and the phytochemical profile of four betalain-rich extracts from Portulaca grandiflora Hook. The HPLC-DAD-ESI-MS analysis indicated the presence of 19 betaxanthins and two betacyanins. The highest concentrations of betaxanthins (982 mg/100 g DE) and betacyanins (650 mg/100 g DE) were noticed in orange and purple flowers extracts, respectively. The HPLC-DAD-ESI-HRMS/MS analyses revealed the presence of a total of 71 compounds. Fifteen new betaxanthins and fifty other metabolites were identified for the first time. The antioxidant activity of the studied flower extracts increased in the sequence of yellow < orange < purple < red (0.066−0.176 mM TE/g DE). Betalains showed less effect on the antioxidant activity of extracts than other metabolites did. Extracts from yellow and orange flowers were more active against Gram-positive bacteria (MIC = 4−16 mg/L), whereas extracts from red and purple flowers were slightly more active against Gram-negative bacteria (MIC = 16−32 mg/L). All the extracts showed the same activity against yeasts (MIC = 32 mg/L). Betaxanthins were active against Gram-positive bacteria, whereas betacyanins were active against Gram-negative bacteria. Remaining metabolites also exhibited antimicrobial activities. The cytotoxicity assessment showed that the P. grandiflora extracts were non-toxic to normal VERO cells. No significant antiviral activity towards Human Herpesvirus type 1 was observed (62 µg/mL). Among the tested varieties, the purple one showed anticancer selectivity towards colon carcinoma cells (RKO).

Antioxidant Capacity Determination of Hungarian-, Slovak-, and Polish-Origin Goldenrod Honeys

The goldenrod (Solidago) species are flowering plants that produce nectar and can be the sources of unifloral honeys. S. canadensis and S. gigantea are native to North America and invasive in several European countries, while S. virgaurea is native to Europe. The aim of this work was to determine and compare the antioxidant capacity of goldenrod honeys collected in three central European countries (Hungary, Poland, and Slovakia), from three locations within each country. The botanical origin of each honey sample was checked with melissopalynological analysis. Color intensity was determined using the Pfund scale. The antioxidant activity was determined with different spectrophotometric methods (DPPH, ABTS, and FRAP). The content of total polyphenols, flavonoids, and phenolic acids was quantified using spectrophotometric methods. The highest radical-scavenging activity was identified for Hungarian samples with all three antioxidant capacity assays. Medium antioxidant activity was described for Slovak samples. The DPPH and ABTS assays discriminated Polish honeys with the lowest antioxidant activity. The highest flavonoid and phenolic acid content was detected in Hungarian and Slovak honeys, while the lowest values were measured in Polish samples. Our study shows that the antioxidant capacity of unifloral goldenrod honeys can be different in various countries of origin, correlating with color intensity and polyphenol content.