Watermelon is the most significant, natural plant source of L-citrulline, a non-proteinaceous amino acid that benefits cardiovascular health and increases vasodilation in many tissues of the body. Watermelon is a member of the Cucurbitaceae, which includes squash, melon, pumpkin, and cucumber. It is possible that other cucurbits could be good sources of citrulline or of arginine, its direct precursor. Twenty-one cultigens were evaluated in triplicate at two locations in North Carolina to estimate citrulline and arginine amounts and variation due to cultigen, replication, and environment. Cultigens containing the highest amount of citrulline (based on LS means) in g/kg fresh weight were ’Crimson Sweet’ watermelon (2.85), ’Dixielee’ watermelon (2.43), casaba-type melon (0.86), mouse melon (0.64), and horned melon rind (0.45). Additionally, mouse melon, horned melon, and bitter gourd (arils) may be interesting sources of arginine-family amino acids, perhaps because of their large seed and aril content relative to mesocarp.

Obesity is a costly and ongoing health complication in the United States and globally. Bioactive-rich foods, especially those providing polyphenols, represent an emerging and attractive strategy to address this issue. Berry-derived anthocyanins and their metabolites are of particular interest for their bioactive effects, including weight maintenance and protection from metabolic aberrations. Earlier findings from small clinical trials suggest modulation of substrate oxidation and glucose tolerance with mediation of prospective benefits attributable to the gut microbiota, but mixed results suggest appropriate anthocyanin dosing poses a challenge. The objective of this randomized, placebo-controlled study was to determine if anthocyanin-dense elderberry juice (EBJ) reproduces glucoregulatory and substrate oxidation effects observed with other berries and if this is mediated by the gut microbiota. Overweight or obese adults (BMI > 25 kg/m²) without chronic illnesses were randomized to a 5-week crossover study protocol with two 1-week periods of twice-daily EBJ or placebo (PL) separated by a washout period. Each treatment period included 4 days of controlled feeding with a 40% fat diet to allow for comparison of measurements in fecal microbiota, meal tolerance testing (MTT), and indirect calorimetry between test beverages. Eighteen study volunteers completed the study. At the phylum level, EBJ significantly increased Firmicutes and Actinobacteria, and decreased Bacteroidetes. At the genus level, EBJ increased Faecalibacterium, Ruminococcaceae, and Bifidobacterium and decreased Bacteroides and lactic acid-producing bacteria, indicating a positive response to EBJ. Supporting the changes to the microbiota, the EBJ treatment significantly reduced blood glucose following the MTT. Fat oxidation also increased significantly both during the MTT and 30 min of moderate physical activity with the EBJ treatment. Our findings confirm the bioactivity of EBJ-sourced anthocyanins on outcomes related to gut health and obesity. Follow-up investigation is needed to confirm our findings and to test for longer durations.

Strawberries (Fragaria × ananassa) are highly valued for their colorful fruit and flavorful taste. Anthocyanins provide much of the red fruit color, and the flavor is highly affected by soluble sugars and non-volatile organic acids. These fruit composition parameters impact consumer decisions. In this study, strawberry fruits from 17 commercial cultivars and advanced selections were collected weekly from replicated trials at three locations in North Carolina. The relative effects of the location and germplasm on fruit composition were determined, including the soluble solid concentration (SSC), titratable acidity (Tacid), and total anthocyanin content (TAC). The breeding criteria of at least 8.0% SSC and 0.80% Tacid were met by eight and six genotypes, respectively and five of these met both criteria. The fruit TAC ranged from 24.0 to 45.7 mg pelargonidin-3-O-glucoside (P3G) equivalents/100 g FWT. P3G was the dominant pigment in all genotypes, followed by pelargonidin-3-O-rutinoside (P3R). As harvest dates advanced, pH, TAC, P3G, P3R, and pelargonidin-3-O-(6″-malonylglucoside) (P3MG) generally decreased, while Tacid, SSC, and cyanidin-3-O-glucoside (C3G) increased. Composition of field-grown strawberries in this mid-Atlantic location were more influenced by the genotype and harvest date than by the growing location.

Eastern redbud, Cercis canadensis L., is a popular ornamental tree in the U.S. and has flower colors of purple-type, red-type, and white-type. Most redbuds cultivars have purple-type flowers. Red-types and white-types are much less common. These unusual flower colors have become an important trait for incorporation into novel redbud cultivars. Eastern redbud seedlings require 3–5 years before blooming, making flower color selection a slow and expensive process. The ability to select seedlings for flower color type would significantly increase the efficiency of the breeding process. Redbud flower color is dominated by anthocyanin content; leaf petioles often show visible pink to purple color, indicating the potential presence of anthocyanin. In this study, anthocyanin profiles of 14 cultivars and 25 progenies of ‘Appalachian Red’ (red-type) × ‘Oklahoma’ (purple-type) were determined using HPLC. The petiole anthocyanin profiles were strongly indicative of plant flower-color types. Both peonidin-3-glucoside and malvidin-3-glucoside were dominant in petioles from all purple-type plants. In contrast, malvidin-3-glucoside was absent from petioles of red-type plants, and neither peonidin-3-glucoside nor malvidin-3-glucoside was detected among white-type cultivars. These results indicate that the presence or absence of peonidin-3-glucoside and malvidin-3-glucoside in petioles can be a physiological marker for identifying redbud flower color types.