Impact of greenhouse vs. open field cultivation on volatiles, phenolics, organic acids, antimicrobial activity, phenology, and molecular bioactivity of kumquat (Fortunella margarita) fruits

Abstract

This study investigated the impacts of open field and greenhouse cultivations on the phenological, physicochemical, antioxidant activity, antimicrobial activity, and in silico bioactivities, including toxicity prediction, of Fortunella margarita fruits. Greenhouse accelerated the phenological development but prolonged the harvest period, while the open field produced higher yield (4650.5 vs. 2397.9 g⸳plant^-1), fruit size, and juice. Additionally, superior nutritional quality, with higher vitamin C (90.24 mg⸳100 g^-1 fw), total phenolics (245.19 mg GAE⸳kg^-1 fw), flavonoids (31.48 mg QE⸳kg^-1 fw), and antioxidant activity (67.19 %) was observed in open field harvested fruits. GC-MS analysis revealed significant variations in major essential oils, namely limonene, germacrene D, and β-myrcene, between systems. Molecular docking indicated strong chlorogenic acid and quercetin binding affinities to key microbial enzymes (-130.46 and -100.17 kcal⸳mol^-1, respectively). Toxicity predictions indicated low toxicity for most compounds. These findings underscore the key role of cultivation environment in modulating functional and biochemical attributes of kumquat.

Keywords: Antimicrobial activities; Cultivation systems; Fortunella margarita; Physico-chemical properties.