Unique profiles of potential health-benefitting phenolic compounds in 22 different citrus clones and hybrids

Authors: Manthey, John; Bowman, Kim; Dorado, Christina

Submitted to: ACS Agricultural Science and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/2/2025
Publication Date: 1/14/2026
Citation: Manthey, J.A., Bowman, K.D., Dorado, C. Unique profiles of potential health-benefitting phenolic compounds in 22 different citrus clones and hybrids. ACS Agricultural Science and Technology. 2026. https://doi.org/10.1021/acsagscitech.5c00597.
DOI: https://doi.org/10.1021/acsagscitech.5c00597

Interpretive Summary: The value of Florida citrus comes mainly from fruit juice processing. However, components from the processed fruit, such as bioactive compounds, can garner a greater dollar per mass value than juice. Obtaining value from every part of the fruit is particularly important when production has been so negatively impacted by citrus huanglongbing, which is now endemic in Florida. New rootstocks and scion varieties with improved performance in the field against environmental and disease stressors such as citrus huanglongbing can be developed through hybridization. Hybrids from many of these crosses exhibit tolerance to huanglongbing but produce fruit that is not tasty as juice. However, many of these huanglongbing-tolerant hybrids contain valuable bioactive compounds with positive implications for health. The fruit of 22 clones and experimental hybrids from the USDA citrus breeding program that exhibit some field tolerance to citrus greening were analyzed for their potential as a source for high-value bioactive compounds. The majority of the clones and experimental hybrids have phenolic compositions similar to their parents and most contained compounds associated with the grapefruit/drug interaction. Certain crosses gave fruit with unique combinations of bioactive compounds that do not normally occur together in traditional citrus varieties. Future clinical work is planned on a few of the most promising clones to help establish their value as an additional revenue source for citrus processors and growers.

Technical Abstract: Within the genus Citrus, there occurs a wide range of flavonoids and coumarins that have beneficial effects in mammalian health. Unique profiles of these bioactive compounds were found in citrus clones and experimental citrus hybrids that were created as part of the USDA citrus breeding program. The fruit of 22 clones and experimental hybrids, many with significant field tolerance to Huanglongbing disease (HLB), were analyzed for their flavonoid and coumarin contents. Among these selections, unique profiles of these compounds frequently reflected the phenolic compositions of their genetic parents. Consistently high levels of the polymethoxylated flavones, nobiletin and tangeretin, occurred among common mandarin (Citrus reticulata) cultivars. Hybrids between these mandarins and pummelos (C. maxima) contained similar polymethoxylated flavone profiles, as well as widely different coumarin and linear furanocoumarin profiles. Most of the hybrids contained bergamottin-related compounds involved in the reported grapefruit/drug interactions. The analyses of coumarins and flavonoids profiles were extended to two common varieties of trifoliate orange (Poncirus trifoliata), ‘Flying Dragon’ and ‘Gotha Road’. Unexpectedly large differences in the phenolic compound profiles were detected between these two trifoliate orange varieties. Crosses between trifoliate oranges and mandarins yielded fruit with novel compositions of polymethoxylated flavones and coumarins not normally occurring together in traditional citrus varieties. Hybrids among the various species appear to be a rich source of unique combinations of compounds useful for particular health applications.