You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Chemical"].

Please return the output as a JSON object of the format: {"Chemical": ["Arsenic", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Identification of novel dietary phytochemicals inhibiting the efflux transporter breast cancer resistance protein (BCRP/ABCG2). Breast cancer resistance protein (BCRP/ABCG2) plays an important role in determining the absorption and disposition of consumed xenobiotics including various drugs and dietary phytochemicals and is also one of the prominent efflux transporters involved in multidrug resistance (MDR). In this study, we have investigated the interactions between ABCG2 and 56 naturally-occurring phytochemicals including phenolic acids, flavonoids, triterpenes and other common dietary phytochemicals, as well as two non plant-based compounds (hippuric acid and propyl gallate) using cell- and membrane-based transport inhibition assays. Of the non-flavonoid phytochemicals tested, berberine, celastrol, ellagic acid, limonin, oleanolic acid, propyl gallate, sinapic acid and ursolic acid demonstrated significant inhibition of ABCG2-mediated transport. Chrysoeriol, laricitrin, myricetin 3',4',5'-trimethylether, pinocembrin, quercitrin, tamarixetin, tricetin and tricetin 3',4',5'-trimethylether were also identified as novel flavonoid ABCG2 inhibitors. The identified inhibitory activity of dietary phytochemicals on ABCG2 provides a framework for further investigation of ABCG2-modulated phytochemical bioavailability, MDR, and possible food-drug interactions.
{"Chemical": ["Chrysoeriol", "laricitrin", "quercitrin", "sinapic acid", "oleanolic acid", "tricetin 3\u0027,4\u0027,5\u0027-trimethylether", "flavonoid", "berberine", "flavonoids", "propyl gallate", "tricetin", "tamarixetin", "celastrol", "myricetin 3\u0027,4\u0027,5\u0027-trimethylether", "ellagic acid", "phenolic acids", "triterpenes", "ursolic acid", "hippuric acid", "limonin", "pinocembrin"]}