Barringtonia racemosa leaf water extract (BLE) had been shown to have high gallic acid (GA) content and BLE has been postulated to have anti-proliferative effects towards colorectal cancer. This study aims to further investigate the mechanism underlying the anti-proliferative effect of BLE in Caco-2 cells and to determine if GA is responsible for the observed effects. Both BLE and GA inhibited Caco-2 cells in a dose-dependent manner. Cells exposed to IC 50 concentration of BLE and GA showed reduced antioxidant activities. GA-treated Caco-2 cells experienced higher oxidative stress compared to cells treated with BLE. Both BLE and GA significantly up-regulated the expression of SLC2A1. BLE but not GA, significantly down-regulated the expression of ADH4. Meanwhile, GA but not BLE, significantly up-regulated AKRIB10 and GLO1 but significantly down-regulated HAGH. Alterations in gene expression were coupled with changes in extracellular glucose and pyruvate levels. While BLE decreased intracellular pyruvate, GA did the opposite. Both intracellular and extracellular D-lactate were not affected by either BLE or GA. GA showed more pronounced effects on apoptosis while BLE irreversibly reduced cell percentage in the G0/G1 phase. In conclusion, this study demonstrates the multiple-actions of BLE against Caco-2 cells, potentially involving various polyphenolic compounds, including GA. Barringtonia racemosa (L.) Spreng is a medicinal plant belonging to the Lecythideceae family that is commonly found throughout Eastern Africa, Polynesia, Africa and Asia including Malaysia 1. In Malaysia, the shoot and young leaves of B. racemosa are usually consumed raw as a salad with various condiments, and different parts of the plant are used in traditional medicine 2. Studies on various parts of B. racemosa have demonstrated its biological activities that includes antibacterial 3 , antifungal 4 , antioxidant 5 , anti-inflammatory 6 and anti-cancer 7-9. Initial analysis performed by our group indicated that the leaf water extract of B. racemosa (BLE) had the highest polyphenolic and ascorbic acid content as well as antioxidant activities amongst various extracts prepared in solvents of different polarities, including water, ethanol, ethyl acetate and hexane 10. Ultra-high performance liquid chromatography (UHPLC) analyses of the BLE revealed the presence of gallic acid (GA), protocathechuic acid, ellagic acid, quercetin, kaempferol and rutin 10,11. The anti-proliferative activities of B. racemosa leaf extract was reported against cervical cancer cell line, HeLa 7 , tumour in mice challenged with Dalton's Lymphoma Ascitic cells 9 and leukemic cell lines, MOLT-3 and REH 8. A recent study conducted by our group found that BLE had a direct effect on the regulation of gene expression in HepG2 cells 12. Further in-silico analysis using Ingenuity Pathway Analysis (IPA) software revealed that the effect of BLE was associated to "cancer, cell death and survival and cell movement" and "cell cycle, connective tissue development and function, cellula...